\( \usepackage{euler} % must be loaded before fontspec for the whole doc (below); this must be kept for pngmath, however \usepackage{hyperref} \usepackage{amsmath} \usepackage{amsbsy} %\usepackage{mathabx} \usepackage{underscore} \usepackage[all]{xy} % Metadata of the pdf output \hypersetup{pdftitle={Yade Documentation}} \hypersetup{pdfauthor={Smilauer, V., et al.}} \hypersetup{pdfkeywords={Discrete element method, granular materials, contact law, hydromechanical coupling}} % symbols \renewcommand{\mat}{\boldsymbol} \renewcommand{\vec}{\boldsymbol} \renewcommand{\tens}{\boldsymbol} %normalized and locfram here \def\normalized#1{\widehat{#1}} \def\locframe#1{\widetilde{#1}} % timestep \def\Dt{\Delta t} \def\Dtcr{\Dt_{\rm cr}} % algorithm complexity \def\bigO#1{{\mathcal{O}(#1)}} % variants for greek symbols \let\epsilon\varepsilon \let\theta\vartheta \let\phi\varphi % shorthands \let\sig\sigma \let\eps\epsilon % variables at different points of time \def\prev#1{#1^-} \def\pprev#1{#1^\ominus} \def\curr#1{#1^{\circ}} \def\nnext#1{#1^\oplus} \def\next#1{#1^+} % shorthands for geometry \def\currn{\curr{\vec{n}}} \def\currC{\curr{\vec{C}}} \def\uT{\vec{u}_T} \def\curruT{\curr{\vec{u}}_T} \def\prevuT{\prev{\vec{u}}_T} \def\currn{\curr{\vec{n}}} \def\prevn{\prev{\vec{n}}} % motion \def\pprevvel{\pprev{\dot{\vec{u}}}} \def\nnextvel{\nnext{\dot{\vec{u}}}} \def\curraccel{\curr{\ddot{\vec{u}}}} \def\prevpos{\prev{\vec{u}}} \def\currpos{\curr{\vec{u}}} \def\nextpos{\next{\vec{u}}} \def\curraaccel{\curr{\dot{\vec{\omega}}}} \def\pprevangvel{\pprev{\vec{\omega}}} \def\nnextangvel{\nnext{\vec{\omega}}} \def\loccurr#1{\curr{\locframe{#1}}} \def\numCPU{n_{\rm cpu}} \DeclareMathOperator{\Align}{Align} \DeclareMathOperator{\sign}{sgn} % sorting algorithms \def\isleq#1{\currelem{#1}\ar@/^/[ll]^{\leq}} \def\isnleq#1{\currelem{#1}\ar@/^/[ll]^{\not\leq}} \def\currelem#1{\fbox{$#1$}} \def\sortSep{||} \def\sortInv{\hbox{\phantom{||}}} \def\sortlines#1{\xymatrix@=3pt{#1}} \def\crossBound{||\mkern-18mu<} \)

# Yade wrapper class reference

## Bodies

### Body

class yade.wrapper.Body(inherits Serializable)

  A particle, basic element of simulation; interacts with other bodies.

  property aspherical

    Whether this body has different inertia along principal axes; NewtonIntegrator makes use of this flag to call rotation integration routine for aspherical bodies, which is more expensive.

  property bound

    Bound, approximating volume for the purposes of collision detection.

  property bounded

    Whether this body should have Body.bound created. Note that bodies without a bound do not participate in collision detection. (In c++, use `Body::isBounded`/`Body::setBounded`)

  property clumpId

    Id of clump this body makes part of; invalid number if not part of clump; see Body::isStandalone, Body::isClump, Body::isClumpMember properties.

    Not meant to be modified directly from Python, use O.bodies.appendClumped instead.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property dynamic

    Whether this body will be moved by forces. (In c++, use `Body::isDynamic`/`Body::setDynamic`)

  property flags

    Bits of various body-related flags. Do not access directly. In c++, use isDynamic/setDynamic, isBounded/setBounded, isAspherical/setAspherical. In python, use Body.dynamic, Body.bounded, Body.aspherical.

  property groupMask

    Bitmask for interaction detection purposes: it is required that two bodies have at least one bit in common in their groupMask for their interaction to be possible from the Collider point of view.

  property id

    Unique id of this body.

  intrs((Body)arg1) → list :

    Return list of all real interactions in which this body participates.

  property isClump

    True if this body is clump itself, false otherwise.

  property isClumpMember

    True if this body is clump member, false otherwise.

  property isFluidDomainBox

    Whether this body is a Fluid grid bounding box should have Body.bound created. FluidDomainBboxes` do not participate to collision detection with their own bodies, they may interact with external bodies and other subdomains through virtual interactions. (In c++, use `Body::getIsFluidDomainBbox`/`Body::setIsFluidDomainBbox`)

  property isStandalone

    True if this body is neither clump, nor clump member; false otherwise.

  property isSubdomain

    Whether this body is a subdomain should have Body.bound created. Subdomains` do not participate to collision detection with their own bodies, they may interact with external bodies and other subdomains through virtual interactions. (In c++, use `Body::getIsSubdomain`/`Body::setIsSubdomain`)

  property iterBorn

    Step number at which the body was added to simulation.

  property mask

    Shorthand for Body::groupMask

  property mat

    Shorthand for Body::material

  property material

    Material instance associated with this body.

  property shape

    Geometrical Shape.

  property state

    Physical state.

  property subdomain

    the subdomain this body belongs to.

  property timeBorn

    Time at which the body was added to simulation.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### Shape

Inheritance graph of Shape.

class yade.wrapper.Shape(inherits Serializable)

  Geometry of a body

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property highlight

    Whether this Shape will be highlighted when rendered.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Box(inherits Shape → Serializable)
  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property extents

    Half-size of the cuboid

  getVolume((Box)arg1) → float :

    Returns the shape volume.

  property highlight

    Whether this Shape will be highlighted when rendered.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.ChainedCylinder(inherits Cylinder → Sphere → Shape → Serializable)

  Geometry of a deformable chained cylinder, using geometry Cylinder.

  property chainedOrientation

    Deviation of node1 orientation from node-to-node vector

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  getVolume((Sphere)arg1) → float :

    Returns the shape volume.

  property highlight

    Whether this Shape will be highlighted when rendered.

  property initLength

    tensile-free length, used as reference for tensile strain

  property length

    Length [m]

  property radius

    Radius [m]

  property segment

    Length vector

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Clump(inherits Shape → Serializable)

  Rigid aggregate of bodies whose usage is detailed here

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property highlight

    Whether this Shape will be highlighted when rendered.

  property ids

    Ids of constituent particles (only informative; direct modifications will have no effect).

  property members

    Return clump members as {‘id1’:(relPos,relOri),…}

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Cylinder(inherits Sphere → Shape → Serializable)

  Geometry of a cylinder, as Minkowski sum of line and sphere.

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  getVolume((Sphere)arg1) → float :

    Returns the shape volume.

  property highlight

    Whether this Shape will be highlighted when rendered.

  property length

    Length [m]

  property radius

    Radius [m]

  property segment

    Length vector

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.DeformableCohesiveElement(inherits DeformableElement → Shape → Serializable)

  Tetrahedral Deformable Element Composed of Nodes

  addFace((DeformableElement)arg1, (yade._minieigenHP.Vector3)arg2) → None :

    Add a face into the element

  addNode((DeformableElement)arg1, (Body)arg2) → None :

    Add a node shared_pt<:yref:’Body’>& as into the element

  addPair((DeformableCohesiveElement)arg1, (Body)arg2, (Body)arg3) → None :

    Add a node shared_pt<:yref:’Body’>& as into the element

  property color

    Color for rendering (normalized RGB).

  delNode((DeformableElement)arg1, (Body)arg2) → None :

    Remove a node shared_pt<:yref:’Body’>& from the element

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property elementframe

    None( (yade.wrapper.DeformableElement)arg1) -> object

  property faces

    Faces of the element for drawing

  getNode((DeformableElement)arg1, (int)arg2) → Body :

    Get a node shared_pt<:yref:’Body’>& as into the element

  getVolume((DeformableElement)arg1) → float :

    Get volume of the element

  property highlight

    Whether this Shape will be highlighted when rendered.

  property localmap

    Ids and relative positions+orientations of members of the deformable element (should not be accessed directly)

  property nodepairs

    Ids and relative position+orientation difference of members of the cohesive deformable element in the inital condition (should not be accessed directly)

  removeLastFace((DeformableElement)arg1) → None :

    Remove a face from the element

  removePair((DeformableCohesiveElement)arg1, (Body)arg2, (Body)arg3) → None :

    Add a node shared_pt<:yref:’Body’>& as into the element

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.DeformableElement(inherits Shape → Serializable)

  Deformable aggregate of nodes

  addFace((DeformableElement)arg1, (yade._minieigenHP.Vector3)arg2) → None :

    Add a face into the element

  addNode((DeformableElement)arg1, (Body)arg2) → None :

    Add a node shared_pt<:yref:’Body’>& as into the element

  property color

    Color for rendering (normalized RGB).

  delNode((DeformableElement)arg1, (Body)arg2) → None :

    Remove a node shared_pt<:yref:’Body’>& from the element

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property elementframe

    None( (yade.wrapper.DeformableElement)arg1) -> object

  property faces

    Faces of the element for drawing

  getNode((DeformableElement)arg1, (int)arg2) → Body :

    Get a node shared_pt<:yref:’Body’>& as into the element

  getVolume((DeformableElement)arg1) → float :

    Get volume of the element

  property highlight

    Whether this Shape will be highlighted when rendered.

  property localmap

    Ids and relative positions+orientations of members of the deformable element (should not be accessed directly)

  removeLastFace((DeformableElement)arg1) → None :

    Remove a face from the element

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Facet(inherits Shape → Serializable)

  Facet (triangular particle) geometry.

  property area

    Facet’s area

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  getVolume((Facet)arg1) → float :

    Returns the shape volume (0 here).

  property highlight

    Whether this Shape will be highlighted when rendered.

  property normal

    Facet’s normal \(\vec n\) (in local coordinate system) oriented towards \(\vec{e_0} \times \vec {e_1}\) with \(\vec {e_0} = \vec{V_0V_1}\), \(\vec {e_1} = \vec{V_1V_2}\) and \(\vec {V_i}\) the vertices

  setVertices((Facet)arg1, (yade._minieigenHP.Vector3)v0, (yade._minieigenHP.Vector3)v1, (yade._minieigenHP.Vector3)v2) → None :

    Defines vertices

    Parameters:

      - v0 (Vector3) – first vertex

      - v1 (Vector3) – second vertex

      - v2 (Vector3) – third vertex

    Returns:

      nothing

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vertices

    Vertex positions in local coordinates.

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.FluidDomainBbox(inherits Shape → Serializable)

  The bounding box of a fluid grid from one OpenFOAM/YALES2 proc

  property bIds

    ids of bodies intersecting with this subdomain,

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property hasIntersection

    if this Yade subdomain has intersection with this OpenFOAM/YALES2 subdomain

  property highlight

    Whether this Shape will be highlighted when rendered.

  property maxBound

    max bounds of the fluid grid

  property minBound

    min bounds of the fluid grid

  property minMaxisSet

    flag to check if the min max bounds of this body are set.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.GridConnection(inherits Sphere → Shape → Serializable)

  GridConnection shape (see [Effeindzourou2016], [Bourrier2013]). Component of a grid designed to link two GridNodes. It is highly recommended to use gridpfacet.gridConnection to generate correct GridConnections.

  addPFacet((GridConnection)arg1, (Body)Body) → None :

    Add a PFacet to the GridConnection.

  property cellDist

    Distance of bodies in cell size units, if using periodic boundary conditions. Note that periodic boundary conditions for GridConnections have not yet been fully implemented.

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  getPFacets((GridConnection)arg1) → object :

    get list of linked PFacets.

  getVolume((Sphere)arg1) → float :

    Returns the shape volume.

  property highlight

    Whether this Shape will be highlighted when rendered.

  property node1

    First Body the GridConnection is connected to.

  property node2

    Second Body the GridConnection is connected to.

  property periodic

    true if two nodes from different periods are connected.

  property radius

    Radius [m]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.GridNode(inherits Sphere → Shape → Serializable)

  GridNode shape, component of a grid. To create a Grid, place the nodes first, they will define the spacial discretisation of it. It is highly recommended to use gridpfacet.gridNode to generate correct GridNodes. Note that the GridNodes should only be in an Interaction with other GridNodes. The Sphere-Grid contact is only handled by the GridConnections.

  addConnection((GridNode)arg1, (Body)Body) → None :

    Add a GridConnection to the GridNode.

  addPFacet((GridNode)arg1, (Body)Body) → None :

    Add a PFacet to the GridNode.

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  getConnections((GridNode)arg1) → object :

    get list of linked GridConnection’s.

  getPFacets((GridNode)arg1) → object :

    get list of linked PFacet’s.

  getVolume((Sphere)arg1) → float :

    Returns the shape volume.

  property highlight

    Whether this Shape will be highlighted when rendered.

  property radius

    Radius [m]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.LevelSet(inherits Shape → Serializable)

  A level set description of particle shape based on a discrete distance field (denoting \(\phi\) the underlying signed distance function) and surface nodes [Duriez2021a] [Duriez2021b]. See examples/levelSet for example scripts.

  assignSurfNodes((LevelSet)arg1, (object)nodes) → None :

    Assigns given nodes (as a list of Vector3r points conforming local frame) to surfNodes, erasing pre-existing ones if any.

  property axesAABE

    The half lengths of the principal axes of the axis-aligned bounding ellipsoid (AABE) of the level-set shape. Format (rx,ry,rz). Only works for VLS-DEM.

  binarize((LevelSet)arg1[, (bool)surface=False]) → object :

    Returns (for any user-defined purpose) a voxellised description of the shape volume. Selection (as being part of the particle) of voxels associated with a strictly zero value of distance depends on surface.

    Parameters:

      surface (bool) – whether to consider particle surface voxels (with a zero distance value) as being part of the volume (if True) or not (if False)

    Returns:

      a 3D grid of 0/1 integers whose [i][j][k] term is 1, resp. 0, when the voxel associated to lsGrid.gridPoint(i,j,k) (see volume for an exact definition of that association) is inside, resp. outside, the particle. Modulo surface considerations, the returned 0/1 values actually correspond to \((\phi-|\phi|)/(2 \phi)\)

  center((LevelSet)arg1) → yade._minieigenHP.Vector3 :

    The center of mass of the volume (considering obviously an uniform density for this volume), in local axes (for verification purposes, by comparison with the origin).

  property color

    Color for rendering (normalized RGB).

  computeMarchingCubes((LevelSet)arg1) → None :

    Compute or recompute the triangulation of the particle surface after using the Marching Cubes algorithm on distField.

  property corners

    The 8 corners of an axis-aligned bounding box, in local axes. It is computed once for all by Bo1_LevelSet_Aabb and used by the same Functor to get Body.bound.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property distField

    The signed (< 0 when inside) distance-to-surface function as a discrete scalar field on lsGrid, with distField[i][j][k] corresponding to lsGrid.gridPoint(i,j,k). From Python, slice this multi-dimensional list with care: while distField[i][:][:] corresponds to values on a x-cst plane, distField[:][:][k] is not at z-constant (use [[distField[i][j][k] for j in ..] for i in ..] instead)

  distance((LevelSet)arg1, (yade._minieigenHP.Vector3)pt[, (bool)unbound=False]) → float :

    Distance to surface at pt, with pt being expressed in the local frame. The ‘unbound’ flag (if True) allows the computation of distance values outside of the grid extents, which otherwise returns NaN together with an error.

  getSurface((LevelSet)arg1[, (float)epsilon=1.0]) → float :

    Compute particle surface by differentiation of Level Set volume around \(\phi = 0\), where best results have usually been obtained using smearCoeff = 1. Given argument epsilon (as a length quantity) serves to initialize the recursive limit search in the derivative expression (see [Duriez2025])

  getVolume((LevelSet)arg1) → float :

    Returns the shape volume as the negative domain of the level set function, in a voxellised fashion, where a negative value of the level set, distField[i][j][k] \(\leq\) 0, is considered to correspond to a material cubic voxel of side lsGrid.spacing and centered at lsGrid.gridPoint(i,j,k). Smearing considerations may apply as per smearCoeff.

  property hasAABE

    Flag to indicate whether an axis-aligned bounding ellipsoid (AABE) has been provided by the user. If true, you must specify axisAABE. Only works for VLS-DEM.

  property highlight

    Whether this Shape will be highlighted when rendered.

  inertia((LevelSet)arg1) → yade._minieigenHP.Vector3 :

    The diagonal coefficients (i.e., eigenvalues, in a consistent workflow) of the geometric inertia matrix (the one considering the infinitesimal volume as the integrand, instead of infinitesimal mass) of the particle volume, as a (xx,yy,zz) Vector3r.

  property lsGrid

    The regular grid carrying distField, in local axes.

  marchingCubesNbTriangles((LevelSet)arg1) → int :

    Returns the number of triangles forming the surface triangulation as per the Marching Cubes algorithm (executed on distField).

  marchingCubesNormals((LevelSet)arg1) → object :

    Returns the normals for a surface triangulation obtained after executing the Marching Cubes algorithm on distField.

  marchingCubesVertices((LevelSet)arg1) → object :

    Returns the vertices for a surface triangulation obtained after executing the Marching Cubes algorithm on distField.

  property n_neighborsNodes

    How many closest nodes we want to store for every one in neighborsNodes (i.e., the \(N\) therein). A negative value leaves the latter uncomputed i.e. empty

  property neighborsNodes

    Denoting n_neighborsNodes as \(N\), neighborsNodes[i] is a \(N+1\) elements iterable with i as the first item, then the indices of the \(N\) closest neighbor nodes for every surface node i, ordered by increasing distance wrt to i.

  normal((LevelSet)arg1, (yade._minieigenHP.Vector3)pt[, (bool)unbound=False]) → yade._minieigenHP.Vector3 :

    Unit normal vector to the surface, at some pt. Local frame applies to both output normal and input pt. Has an ‘unbound’ flag signaling whether to allow (if True) the computation of the normal outside of the grid extents.

  rayTrace((LevelSet)arg1, (yade._minieigenHP.Vector3)ray[, (float)nodesTol=50]) → object :

    Performs one ray tracing along ray (to be given in cartesian coordinates, see spher2cart() if a conversion is useful from spherical ones; norm should not matter) and returns the obtained surface points (without modifying surfNodes). Argument nodesTol has the same meaning as in rayTraceSurfNodes, see therein. Provided for debugging or shape analysis purposes.

  rayTraceSurfNodes((LevelSet)arg1[, (int)nSurfNodes=102[, (int)nodesPath=2[, (float)nodesTol=50]]]) → None :

    Defines all surface nodes (i.e., surfNodes) by ray tracing, erasing pre-existing ones if any, according to given arguments

    Parameters:

      - nSurfNodes (int) – how many rays are to be launched. Please use a perfect square + 2 if not twoD and if nodesPath = 1. Previously coined nNodes in [Duriez2021b]

      - nodesPath (int) – defines how the space of spherical coordinates \((\theta \in [0;\pi] ,\varphi\in [0;2 \pi])\) is discretized when ray tracing the boundary nodes: 1 gives a rectangular partition of that space, plus two nodes at \(\theta = 0 [\pi]\); 2 locates the nodes along a spiral path [Duriez2021a]

      - nodesTol (real) – tolerance coefficient for accepting (if \(|\phi| / L <\) nodesTol \(\times\) numeric precision with \(\phi\) the return value of distance and \(L\) a body-characteristic length taken as \(\sqrt[3]{V}\) with \(V\) the volume, or \(\sqrt{V/g_{grid}}\) with \(g_{grid}\) the grid spacing if twoD) surface nodes proposed by the ray tracing algorithm

  property smearCoeff

    Rules the smearing coefficient \(\varepsilon > 0\) of the Heaviside step function for a smooth integration of the particle’s volume close to its surface (the higher \(\varepsilon\) the smoother, i.e. the more diffuse the surface in terms of volume integration). Given in reciprocal multiples of \(R_{cell} = \sqrt{3}/2 g_{grid}\) the half diagonal of the cells of the lsGrid with \(g_{grid}\) the cell length: \(\varepsilon = R_{cell}\times 1/\) smearCoeff (smearing is deactivated if negative).

  property sphericity

    Shape sphericity computed from boundary nodes and assuming both largest inscribed sphere and smallest circumscribed sphere have the origin (of local axes) as center.

  property starLike

    Indicates whether surface nodes are ray-traced considering that a ray can intersect the surface no more than once.

  property surfNodes

    Surface discretization in terms of (a list of) nodes, for the master-slave refined contact treatment in Ig2_LevelSet_LevelSet_ScGeom, previously coined boundNodes in [Duriez2021b]. Expressed in local frame.

  property twoD

    True for z-invariant shapes. Serves to restrict the ray tracing of surfNodes in the (x,y) plane.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  volume((LevelSet)arg1) → float :

    A 2025/09-deprecated version of getVolume. Please use the latter instead.

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Lin4NodeTetra(inherits DeformableElement → Shape → Serializable)

  Tetrahedral Deformable Element Composed of Nodes

  addFace((DeformableElement)arg1, (yade._minieigenHP.Vector3)arg2) → None :

    Add a face into the element

  addNode((DeformableElement)arg1, (Body)arg2) → None :

    Add a node shared_pt<:yref:’Body’>& as into the element

  property color

    Color for rendering (normalized RGB).

  delNode((DeformableElement)arg1, (Body)arg2) → None :

    Remove a node shared_pt<:yref:’Body’>& from the element

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property elementframe

    None( (yade.wrapper.DeformableElement)arg1) -> object

  property faces

    Faces of the element for drawing

  getNode((DeformableElement)arg1, (int)arg2) → Body :

    Get a node shared_pt<:yref:’Body’>& as into the element

  getVolume((DeformableElement)arg1) → float :

    Get volume of the element

  property highlight

    Whether this Shape will be highlighted when rendered.

  property localmap

    Ids and relative positions+orientations of members of the deformable element (should not be accessed directly)

  removeLastFace((DeformableElement)arg1) → None :

    Remove a face from the element

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Lin4NodeTetra_Lin4NodeTetra_InteractionElement(inherits DeformableCohesiveElement → DeformableElement → Shape → Serializable)

  Tetrahedral Deformable Element Composed of Nodes

  addFace((DeformableElement)arg1, (yade._minieigenHP.Vector3)arg2) → None :

    Add a face into the element

  addNode((DeformableElement)arg1, (Body)arg2) → None :

    Add a node shared_pt<:yref:’Body’>& as into the element

  addPair((DeformableCohesiveElement)arg1, (Body)arg2, (Body)arg3) → None :

    Add a node shared_pt<:yref:’Body’>& as into the element

  property color

    Color for rendering (normalized RGB).

  delNode((DeformableElement)arg1, (Body)arg2) → None :

    Remove a node shared_pt<:yref:’Body’>& from the element

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property elementframe

    None( (yade.wrapper.DeformableElement)arg1) -> object

  property faces

    Faces of the element for drawing

  getNode((DeformableElement)arg1, (int)arg2) → Body :

    Get a node shared_pt<:yref:’Body’>& as into the element

  getVolume((DeformableElement)arg1) → float :

    Get volume of the element

  property highlight

    Whether this Shape will be highlighted when rendered.

  property localmap

    Ids and relative positions+orientations of members of the deformable element (should not be accessed directly)

  property nodepairs

    Ids and relative position+orientation difference of members of the cohesive deformable element in the inital condition (should not be accessed directly)

  removeLastFace((DeformableElement)arg1) → None :

    Remove a face from the element

  removePair((DeformableCohesiveElement)arg1, (Body)arg2, (Body)arg3) → None :

    Add a node shared_pt<:yref:’Body’>& as into the element

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Node(inherits Shape → Serializable)

  Geometry of node particle.

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property highlight

    Whether this Shape will be highlighted when rendered.

  property radius

    Radius [m]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.PFacet(inherits Shape → Serializable)

  PFacet (particle facet) geometry (see [Effeindzourou2016], [Effeindzourou2015a]). It is highly recommended to use the helper functions in gridpfacet (e.g., gridpfacet.pfacetCreator1-4) to generate correct PFacet elements.

  property area

    PFacet’s area

  property cellDist

    Distance of bodies in cell size units, if using periodic boundary conditions. Note that periodic boundary conditions for PFacets have not yet been fully implemented.

  property color

    Color for rendering (normalized RGB).

  property conn1

    First Body the Pfacet is connected to.

  property conn2

    Second Body the Pfacet is connected to.

  property conn3

    third Body the Pfacet is connected to.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property highlight

    Whether this Shape will be highlighted when rendered.

  property node1

    First Body the Pfacet is connected to.

  property node2

    Second Body the Pfacet is connected to.

  property node3

    third Body the Pfacet is connected to.

  property normal

    PFacet’s normal (in local coordinate system)

  property radius

    PFacet’s radius

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.PotentialParticle(inherits Shape → Serializable)

  EXPERIMENTAL. Geometry of PotentialParticle.

  property AabbMinMax

    Whether the exact Aabb should be calculated. If false, an approximate cubic Aabb is defined with edges of `2R`

  property R

    R in Potential Particles

  property a

    List of a coefficients of plane normals

  property b

    List of b coefficients of plane normals

  property boundaryNormal

    Normal direction of boundary if fixedNormal=True

  property c

    List of c coefficients of plane normals

  property color

    Color for rendering (normalized RGB).

  property d

    List of d coefficients of plane normals

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property fixedNormal

    Whether to fix the contact normal at a boundary, using boundaryNormal

  property highlight

    Whether this Shape will be highlighted when rendered.

  property id

    Particle id (for graphics in vtk output)

  property isBoundary

    Whether the particle is part of a boundary particle

  property k

    k in Potential Particles

  property maxAabb

    Max from box centre: Used for visualisation in vtk and qt

  property maxAabbRotated

    Max from box centre: Used for primary contact detection

  property minAabb

    Min from box centre: Used for visualisation in vtk and qt

  property minAabbRotated

    Min from box centre: Used for primary contact detection

  property r

    r in Potential Particles

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vertices

    Vertices

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Sphere(inherits Shape → Serializable)

  Geometry of spherical particle.

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  getVolume((Sphere)arg1) → float :

    Returns the shape volume.

  property highlight

    Whether this Shape will be highlighted when rendered.

  property radius

    Radius [m]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Subdomain(inherits Shape → Serializable)

  The bounding box of a mpi subdomain. Stores internals and provides optimized functions for communications between workers. This class may not be used directly. Instead, Subdomains are appended automatically to the scene bodies when using mpy.mpirun

  boundOnAxis((Subdomain)arg1, (Bound)bound, (yade._minieigenHP.Vector3)axis, (bool)min) → float :

    computes projected position of a bound in a certain direction

    boundOnAxis( (Subdomain)arg1, (Bound)bound, (yade._minieigenHP.Vector3)axis, (bool)min) -> float :

      computes projected position of a bound in a certain direction

  property boundsMax

    max corner of all bboxes of members; differs from effective domain bounds by the extra length (sweepLength)

  property boundsMin

    min corner of all bboxes of members; differs from effective domain bounds by the extra length (sweepLength)

  centerOfMass((Subdomain)arg1) → yade._minieigenHP.Vector3 :

    returns center of mass of assigned bodies

    centerOfMass( (Subdomain)arg1) -> yade._minieigenHP.Vector3 :

      returns center of mass of assigned bodies

  cleanIntersections((Subdomain)arg1, (int)otherDomain) → None :

    makes sure that the ids in the current subdomain belong to the current subdomain

  property color

    Color for rendering (normalized RGB).

  property comm

    Communicator to be used for MPI (converts mpi4py comm <-> c++ comm)

  completeSendBodies((Subdomain)arg1) → None :

    calls MPI_wait to complete the non blocking sends/recieves.

  countIntsWith((Subdomain)arg1, (int)body, (int)someSubDomain[, (Scene)someSubDomain=<Scene instance at 0x22eb8c10>]) → int :

    returns for a body the count of interactions (real or virtual) with bodies from a certain subdomain, interactions with subdomains excluded. Third parameter (scene pointer) can be left to default (equivalent to O._sceneObj).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property extraLength

    verlet dist for the subdomain, added to bodies verletDist

  filterIntersections((Subdomain)arg1) → float :

    clear intersections and mirror intersections of all non-interacting bodies.

  filteredInts((Subdomain)arg1, (int)someSubDomain, (bool)mirror) → object :

    return a copy of intersections or mirrorIntersections from which non-interacting bodies have been removed.

  getMirrorIntrs((Subdomain)arg1) → None :

    get mirrorIntersections from other subdomains

  getRankSize((Subdomain)arg1) → None :

    set subdomain ranks, used for communications -> merging, sending bodies etc.

  getStateBoundsValuesFromIds((Subdomain)arg1, (object)b_ids) → object :

    returns pos,vel,angVel,ori,bounds of listed bodies.

  getStateValues((Subdomain)arg1, (int)otherDomain) → object :

    returns pos,vel,angVel,ori of bodies interacting with a given otherDomain, based on Subdomain.intersections.

  getStateValuesFromIds((Subdomain)arg1, (object)b_ids) → object :

    returns pos,vel,angVel,ori of listed bodies.

  property highlight

    Whether this Shape will be highlighted when rendered.

  property ids

    Ids of owned particles.

  init((Subdomain)arg1) → None :

    Initialize subdomain variables as rank and buffer sizes, call this from each thread after scene distribution by master.

  property intersections

    lists of bodies from this subdomain intersecting other subdomains. WARNING: only assignement and concatenation allowed

  medianFilterCPP((Subdomain)arg1, (int)arg2, (yade._minieigenHP.Vector3)bodiesToRecv, (yade._minieigenHP.Vector3)otherSubdomain, (int)oterSubdomainCenterofMass, (bool)useAABB) → object :

    cpp version of median filter, used for body reallocation operations.

  mergeOp((Subdomain)arg1) → None :

    merge with setting interactions

  migrateBodiesSend((Subdomain)arg1, (object)bodiesToSend, (int)destination) → None :

    ids of body to be sent have their subdomain parameter reassigned, followed by sendBodies

  property mirrorIntersections

    lists of bodies from other subdomains intersecting this one. WARNING: only assignement and concatenation allowed

  mpiIrecvStates((Subdomain)arg1, (int)otherSubdomain) → None :

    mpi-Irecv states from another domain (non-blocking)

  mpiRecvStates((Subdomain)arg1, (int)otherSubdomain) → None :

    mpi-recv states from another domain (blocking)

  mpiSendStates((Subdomain)arg1, (int)otherSubdomain) → None :

    mpi-send states from current domain to another domain (blocking)

  mpiWaitReceived((Subdomain)arg1, (int)otherSubdomain) → None :

    mpi-Wait states from another domain (upon return the buffer is set)

  receiveBodies((Subdomain)arg1, (int)sender) → None :

    Receive the bodies from MPI sender rank to MPI receiver rank

  sendBodies((Subdomain)sender, (int)receiver, (object)idsToSend) → None :

    Copy the bodies from MPI sender rank to MPI receiver rank

  setIDstoSubdomain((Subdomain)arg1, (list)idList) → None :

    set list of ids to the subdomain.

  setMinMax((Subdomain)arg1) → None :

    returns bounding min-max based on members bounds. precondition: the members bounds have been dispatched already, else we re-use old values. Carefull if subdomain is not at the end of O.bodies.

  setStateBoundsValuesFromIds((Subdomain)arg1, (object)b_ids, (object)input) → None :

    set pos,vel,angVel,ori,bounds from listed body ids and data.

  setStateValuesFromBuffer((Subdomain)arg1, (int)subdomain) → None :

    set pos,vel,angVel,ori from state buffer.

  setStateValuesFromIds((Subdomain)arg1, (object)b_ids, (object)input) → None :

    set pos,vel,angVel,ori from listed body ids and data.

  splitBodiesToWorkers((Subdomain)arg1, (bool)eraseWorkerBodies) → None :

    of true bodies in workers are erased and reassigned.

  property subdomains

    subdomain ids of other bodies, WARNING: only assignement and concatenation allowed

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  updateLocalIds((Subdomain)arg1, (bool)eraseRemoteMastrer) → None :

    updates the ids in the subdomain id vector, if not eraseRemoteMastrer, body->subdomain in master are updated.

  updateNewMirrorIntrs((Subdomain)arg1, (int)otherdomain, (object)newMirrorList) → None :

    update the mirrorIntersections of a specific subdomain

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Tetra(inherits Shape → Serializable)

  Tetrahedron geometry.

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property highlight

    Whether this Shape will be highlighted when rendered.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property v

    Tetrahedron vertices (in local coordinate system).

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

class yade.wrapper.Wall(inherits Shape → Serializable)

  Object representing infinite plane aligned with the coordinate system (axis-aligned wall).

  property axis

    Axis of the normal; can be 0,1,2 for +x, +y, +z respectively (Body’s orientation is disregarded for walls)

  property color

    Color for rendering (normalized RGB).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Shape)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  getVolume((Wall)arg1) → float :

    Returns the shape volume (0 here).

  property highlight

    Whether this Shape will be highlighted when rendered.

  property sense

    Which side of the wall interacts: -1 for negative only, 0 for both, +1 for positive only

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Whether this Shape is rendered using color surfaces, or only wireframe (can still be overridden by global config of the renderer).

### State

Inheritance graph of State.

class yade.wrapper.State(inherits Serializable)

  State of a body (spatial configuration, internal variables).

  property angMom

    Current angular momentum

  property angVel

    Current angular velocity

  property blockedDOFs

    Degress of freedom where linear/angular velocity will be always constant (equal to zero, or to an user-defined value), regardless of applied force/torque. String that may contain ‘xyzXYZ’ (translations and rotations).

  property densityScaling

    Multiplicative coefficient to reflect an artificial change in mass density (as per GlobalStiffnessTimeStepper.targetDt) which NewtonIntegrator (depending on the corresponding option NewtonIntegrator.densityScaling) will reflect into linear and angular velocities (but not angular momentum that still corresponds to the unbiaised inertia tensor) as a multiplicative coefficient (auto-updated).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((State)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  displ((State)arg1) → yade._minieigenHP.Vector3 :

    Displacement from reference position (pos - refPos)

  property inertia

    Inertia of associated body, in local coordinate system.

  property isDamped

    Damping in NewtonIntegrator can be deactivated for individual particles by setting this variable to FALSE. E.g. damping is inappropriate for particles in free flight under gravity but it might still be applicable to other particles in the same simulation.

  property mass

    Mass of this body

  property ori

    Current orientation as the quaternion-form of the rotation that maps the model, i.e. global, coordinate system into an inertial, i.e. local, basis for the body.

  property pos

    Current position.

  property refOri

    Reference orientation

  property refPos

    Reference position

  rot((State)arg1) → yade._minieigenHP.Vector3 :

    Rotation from reference orientation (as rotation vector)

  property se3

    Position and orientation as one object.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vel

    Current linear velocity.

class yade.wrapper.ChainedState(inherits State → Serializable)

  State of a chained bodies, containing information on connectivity in order to track contacts jumping over contiguous elements. Chains are 1D lists from which id of chained bodies are retrieved via rank and chainNumber.

  addToChain((ChainedState)arg1, (int)bodyId) → None :

    Add body to current active chain

  property angMom

    Current angular momentum

  property angVel

    Current angular velocity

  property bId

    id of the body containing - for postLoad operations only.

  property blockedDOFs

    Degress of freedom where linear/angular velocity will be always constant (equal to zero, or to an user-defined value), regardless of applied force/torque. String that may contain ‘xyzXYZ’ (translations and rotations).

  property chainNumber

    chain id.

  currentChain = 0
  property densityScaling

    Multiplicative coefficient to reflect an artificial change in mass density (as per GlobalStiffnessTimeStepper.targetDt) which NewtonIntegrator (depending on the corresponding option NewtonIntegrator.densityScaling) will reflect into linear and angular velocities (but not angular momentum that still corresponds to the unbiaised inertia tensor) as a multiplicative coefficient (auto-updated).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((State)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  displ((State)arg1) → yade._minieigenHP.Vector3 :

    Displacement from reference position (pos - refPos)

  property inertia

    Inertia of associated body, in local coordinate system.

  property isDamped

    Damping in NewtonIntegrator can be deactivated for individual particles by setting this variable to FALSE. E.g. damping is inappropriate for particles in free flight under gravity but it might still be applicable to other particles in the same simulation.

  property mass

    Mass of this body

  property ori

    Current orientation as the quaternion-form of the rotation that maps the model, i.e. global, coordinate system into an inertial, i.e. local, basis for the body.

  property pos

    Current position.

  property rank

    rank in the chain.

  property refOri

    Reference orientation

  property refPos

    Reference position

  rot((State)arg1) → yade._minieigenHP.Vector3 :

    Rotation from reference orientation (as rotation vector)

  property se3

    Position and orientation as one object.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vel

    Current linear velocity.

class yade.wrapper.CpmState(inherits State → Serializable)

  State information about body use by cpm-model.

  None of that is used for computation (at least not now), only for post-processing.

  property angMom

    Current angular momentum

  property angVel

    Current angular velocity

  property blockedDOFs

    Degress of freedom where linear/angular velocity will be always constant (equal to zero, or to an user-defined value), regardless of applied force/torque. String that may contain ‘xyzXYZ’ (translations and rotations).

  property damageTensor

    Damage tensor computed with microplane theory averaging. state.damageTensor.trace() = state.normDmg

  property densityScaling

    Multiplicative coefficient to reflect an artificial change in mass density (as per GlobalStiffnessTimeStepper.targetDt) which NewtonIntegrator (depending on the corresponding option NewtonIntegrator.densityScaling) will reflect into linear and angular velocities (but not angular momentum that still corresponds to the unbiaised inertia tensor) as a multiplicative coefficient (auto-updated).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((State)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  displ((State)arg1) → yade._minieigenHP.Vector3 :

    Displacement from reference position (pos - refPos)

  property epsVolumetric

    Volumetric strain around this body (unused for now)

  property inertia

    Inertia of associated body, in local coordinate system.

  property isDamped

    Damping in NewtonIntegrator can be deactivated for individual particles by setting this variable to FALSE. E.g. damping is inappropriate for particles in free flight under gravity but it might still be applicable to other particles in the same simulation.

  property mass

    Mass of this body

  property normDmg

    Average damage including already deleted contacts (it is really not damage, but 1-relResidualStrength now)

  property numBrokenCohesive

    Number of (cohesive) contacts that damaged completely

  property numContacts

    Number of contacts with this body

  property ori

    Current orientation as the quaternion-form of the rotation that maps the model, i.e. global, coordinate system into an inertial, i.e. local, basis for the body.

  property pos

    Current position.

  property refOri

    Reference orientation

  property refPos

    Reference position

  rot((State)arg1) → yade._minieigenHP.Vector3 :

    Rotation from reference orientation (as rotation vector)

  property se3

    Position and orientation as one object.

  property stress

    Stress tensor of the spherical particle (under assumption that particle volume = pi*r*r*r*4/3.) for packing fraction 0.62

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vel

    Current linear velocity.

class yade.wrapper.JCFpmState(inherits ThermalState → State → Serializable)

  JCFpm state information about each body.

  property Cp

    Heat capacity of the body

  property Tcondition

    indicates if particle is assigned dirichlet (constant temp) condition

  property alpha

    coefficient of thermal expansion

  property angMom

    Current angular momentum

  property angVel

    Current angular velocity

  property blockedDOFs

    Degress of freedom where linear/angular velocity will be always constant (equal to zero, or to an user-defined value), regardless of applied force/torque. String that may contain ‘xyzXYZ’ (translations and rotations).

  property boundaryId

    identifies if a particle is associated with constant temperature thrermal boundary condition

  property damageIndex

    Ratio of broken bonds over initial bonds. [-]

  property delRadius

    radius change due to thermal expansion

  property densityScaling

    Multiplicative coefficient to reflect an artificial change in mass density (as per GlobalStiffnessTimeStepper.targetDt) which NewtonIntegrator (depending on the corresponding option NewtonIntegrator.densityScaling) will reflect into linear and angular velocities (but not angular momentum that still corresponds to the unbiaised inertia tensor) as a multiplicative coefficient (auto-updated).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((State)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  displ((State)arg1) → yade._minieigenHP.Vector3 :

    Displacement from reference position (pos - refPos)

  property inertia

    Inertia of associated body, in local coordinate system.

  property isCavity

    flag used for unbounding cavity bodies

  property isDamped

    Damping in NewtonIntegrator can be deactivated for individual particles by setting this variable to FALSE. E.g. damping is inappropriate for particles in free flight under gravity but it might still be applicable to other particles in the same simulation.

  property joint

    Indicates the number of joint surfaces to which the particle belongs (0-> no joint, 1->1 joint, etc..). [-]

  property jointNormal1

    Specifies the normal direction to the joint plane 1. Rk: the ideal here would be to create a vector of vector wich size is defined by the joint integer (as much joint normals as joints). However, it needs to make the pushback function works with python since joint detection is done through a python script. lines 272 to 312 of cpp file should therefore be adapted. [-]

  property jointNormal2

    Specifies the normal direction to the joint plane 2. [-]

  property jointNormal3

    Specifies the normal direction to the joint plane 3. [-]

  property k

    thermal conductivity of the body

  property mass

    Mass of this body

  property nbBrokenBonds

    Number of broken bonds. [-]

  property nbInitBonds

    Number of initial bonds. [-]

  property oldTemp

    change of temp (for thermal expansion)

  property onJoint

    Identifies if the particle is on a joint surface.

  property ori

    Current orientation as the quaternion-form of the rotation that maps the model, i.e. global, coordinate system into an inertial, i.e. local, basis for the body.

  property pos

    Current position.

  property refOri

    Reference orientation

  property refPos

    Reference position

  rot((State)arg1) → yade._minieigenHP.Vector3 :

    Rotation from reference orientation (as rotation vector)

  property se3

    Position and orientation as one object.

  property stabilityCoefficient

    sum of solid and fluid thermal resistivities for use in automatic timestep estimation

  property stepFlux

    flux during current step

  property temp

    temperature of the body

  property thermalMass

    mass of the body used for thermal calculations

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vel

    Current linear velocity.

class yade.wrapper.SegmentedState(inherits State → Serializable)

  State information about body coating map used by CohFrictMatSeg. It allows spheres or facets to store information about the coating thickness. The coating thickness for the facets is stored in two fields (positive and negative side of the facets). In the case of spheres, the surface of sphere is divided into segments of equal area (controlled by SegmentedStateUpdater::thetaResolution and SegmentedStateUpdater.phiResolution parameters).

  property allowMatExchange

    If true, material can be exchanged between bodies.This condition needs to be true for material exchange, but also body state needs to be initialized with SegmentedStateUpdater.

  property angMom

    Current angular momentum

  property angVel

    Current angular velocity

  property blockedDOFs

    Degress of freedom where linear/angular velocity will be always constant (equal to zero, or to an user-defined value), regardless of applied force/torque. String that may contain ‘xyzXYZ’ (translations and rotations).

  property coatingThickness

    Vector storing information about coating thickness in each segment. It is assumed that the linear unit of coating thickness is 1000 times smaller than the unit of radius (e.g., if the simulation basic unit is meter, then coating thickness is provided in milimeters). It is one-dimensional, hence for easier intepretation can be reshaped based on the information about thetaResolution and phiResolution.

  property coatingVolume

    Vector storing information about coating volume in each segment (unit is \(1000^3\) smaller than volume unit of the simulation, see SegmentedState.coatingThickness for explanation). It is one-dimensional, hence for easier intepretation can be reshaped based on the information about thetaResolution and phiResolution.

  property densityScaling

    Multiplicative coefficient to reflect an artificial change in mass density (as per GlobalStiffnessTimeStepper.targetDt) which NewtonIntegrator (depending on the corresponding option NewtonIntegrator.densityScaling) will reflect into linear and angular velocities (but not angular momentum that still corresponds to the unbiaised inertia tensor) as a multiplicative coefficient (auto-updated).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((State)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  displ((State)arg1) → yade._minieigenHP.Vector3 :

    Displacement from reference position (pos - refPos)

  property inertia

    Inertia of associated body, in local coordinate system.

  property isDamped

    Damping in NewtonIntegrator can be deactivated for individual particles by setting this variable to FALSE. E.g. damping is inappropriate for particles in free flight under gravity but it might still be applicable to other particles in the same simulation.

  property mass

    Mass of this body

  property needsInit

    Tells SegmentedStateUpdater whether thickness was initialized for given body.

  property ori

    Current orientation as the quaternion-form of the rotation that maps the model, i.e. global, coordinate system into an inertial, i.e. local, basis for the body.

  property pos

    Current position.

  property refOri

    Reference orientation

  property refPos

    Reference position

  rot((State)arg1) → yade._minieigenHP.Vector3 :

    Rotation from reference orientation (as rotation vector)

  property se3

    Position and orientation as one object.

  property segmentArea

    Area of one segment of the body (unit is \(1000^2\) smaller than surface unit of the simulation, see SegmentedState::coatingThickness for explanation).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vel

    Current linear velocity.

class yade.wrapper.ThermalState(inherits State → Serializable)

  State containing quantities for thermal physics.

  property Cp

    Heat capacity of the body

  property Tcondition

    indicates if particle is assigned dirichlet (constant temp) condition

  property alpha

    coefficient of thermal expansion

  property angMom

    Current angular momentum

  property angVel

    Current angular velocity

  property blockedDOFs

    Degress of freedom where linear/angular velocity will be always constant (equal to zero, or to an user-defined value), regardless of applied force/torque. String that may contain ‘xyzXYZ’ (translations and rotations).

  property boundaryId

    identifies if a particle is associated with constant temperature thrermal boundary condition

  property delRadius

    radius change due to thermal expansion

  property densityScaling

    Multiplicative coefficient to reflect an artificial change in mass density (as per GlobalStiffnessTimeStepper.targetDt) which NewtonIntegrator (depending on the corresponding option NewtonIntegrator.densityScaling) will reflect into linear and angular velocities (but not angular momentum that still corresponds to the unbiaised inertia tensor) as a multiplicative coefficient (auto-updated).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((State)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  displ((State)arg1) → yade._minieigenHP.Vector3 :

    Displacement from reference position (pos - refPos)

  property inertia

    Inertia of associated body, in local coordinate system.

  property isCavity

    flag used for unbounding cavity bodies

  property isDamped

    Damping in NewtonIntegrator can be deactivated for individual particles by setting this variable to FALSE. E.g. damping is inappropriate for particles in free flight under gravity but it might still be applicable to other particles in the same simulation.

  property k

    thermal conductivity of the body

  property mass

    Mass of this body

  property oldTemp

    change of temp (for thermal expansion)

  property ori

    Current orientation as the quaternion-form of the rotation that maps the model, i.e. global, coordinate system into an inertial, i.e. local, basis for the body.

  property pos

    Current position.

  property refOri

    Reference orientation

  property refPos

    Reference position

  rot((State)arg1) → yade._minieigenHP.Vector3 :

    Rotation from reference orientation (as rotation vector)

  property se3

    Position and orientation as one object.

  property stabilityCoefficient

    sum of solid and fluid thermal resistivities for use in automatic timestep estimation

  property stepFlux

    flux during current step

  property temp

    temperature of the body

  property thermalMass

    mass of the body used for thermal calculations

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vel

    Current linear velocity.

class yade.wrapper.WireState(inherits State → Serializable)

  Wire state information of each body.

  None of that is used for computation (at least not now), only for post-processing.

  property angMom

    Current angular momentum

  property angVel

    Current angular velocity

  property blockedDOFs

    Degress of freedom where linear/angular velocity will be always constant (equal to zero, or to an user-defined value), regardless of applied force/torque. String that may contain ‘xyzXYZ’ (translations and rotations).

  property densityScaling

    Multiplicative coefficient to reflect an artificial change in mass density (as per GlobalStiffnessTimeStepper.targetDt) which NewtonIntegrator (depending on the corresponding option NewtonIntegrator.densityScaling) will reflect into linear and angular velocities (but not angular momentum that still corresponds to the unbiaised inertia tensor) as a multiplicative coefficient (auto-updated).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((State)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  displ((State)arg1) → yade._minieigenHP.Vector3 :

    Displacement from reference position (pos - refPos)

  property inertia

    Inertia of associated body, in local coordinate system.

  property isDamped

    Damping in NewtonIntegrator can be deactivated for individual particles by setting this variable to FALSE. E.g. damping is inappropriate for particles in free flight under gravity but it might still be applicable to other particles in the same simulation.

  property mass

    Mass of this body

  property numBrokenLinks

    Number of broken links (e.g. number of wires connected to the body which are broken). [-]

  property ori

    Current orientation as the quaternion-form of the rotation that maps the model, i.e. global, coordinate system into an inertial, i.e. local, basis for the body.

  property pos

    Current position.

  property refOri

    Reference orientation

  property refPos

    Reference position

  rot((State)arg1) → yade._minieigenHP.Vector3 :

    Rotation from reference orientation (as rotation vector)

  property se3

    Position and orientation as one object.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vel

    Current linear velocity.

### Material

Inheritance graph of Material.

class yade.wrapper.Material(inherits Serializable)

  Material properties of a body.

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.BubbleMat(inherits Material → Serializable)

  material for bubble interactions, for use with other Bubble classes

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property surfaceTension

    The surface tension in the fluid surrounding the bubbles. The default value is that of water at 25 degrees Celcius.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.CohFrictMat(inherits FrictMat → ElastMat → Material → Serializable)

  Material description extending FrictMat with cohesive properties and rotational stiffnesses. For use e.g. with Law2_ScGeom6D_CohFrictPhys_CohesionMoment.

  property alphaKr

    Dimensionless rolling stiffness.

  property alphaKtw

    Dimensionless twist stiffness.

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property etaRoll

    Dimensionless rolling (aka ‘bending’) strength. If negative, rolling moment will be elastic.

  property etaTwist

    Dimensionless twisting strength. If negative, twist moment will be elastic.

  property fragile

    does cohesion disappear when contact strength is exceeded?

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property isCohesive

    Whether this body can form possibly cohesive interactions (if true and depending on other parameters such as Ip2_CohFrictMat_CohFrictMat_CohFrictPhys.setCohesionNow).

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  property momentRotationLaw

    Use bending/twisting moment at contact. The contact may have moments only if both bodies have this flag true. See Law2_ScGeom6D_CohFrictPhys_CohesionMoment.always_use_moment_law for details.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property normalCohesion

    Tensile strength, homogeneous to a pressure. If negative the normal force is purely elastic.

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property shearCohesion

    Shear strength, homogeneous to a pressure. If negative the shear force is purely elastic.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.CohFrictMatSeg(inherits CohFrictMat → FrictMat → ElastMat → Material → Serializable)

  Material extending CohFrictMat to use dual material properties with segmented bodies (transition between properties depends on the coating thickness). Should be used with Ip2_CohFrictMatSeg_CohFrictMatSeg_CohFrictPhys to benefit from dual material capabilites. The other functors can be the same as for CohFrictMat (e.g. with contact law Law2_ScGeom6D_CohFrictPhys_CohesionMoment). Besides primary set of material parameter of CohFrictMat, some are doubled and called secondary (e.g. secondaryYoung, secondaryNormalCohesion etc.). When this material is used with spheres or facets, a special state (SegmentedState) is assigned to them, allowing to store information about coating thickness.

  property alphaKr

    Dimensionless rolling stiffness.

  property alphaKtw

    Dimensionless twist stiffness.

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property etaRoll

    Dimensionless rolling (aka ‘bending’) strength. If negative, rolling moment will be elastic.

  property etaTwist

    Dimensionless twisting strength. If negative, twist moment will be elastic.

  property fragile

    does cohesion disappear when contact strength is exceeded?

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property isCohesive

    Whether this body can form possibly cohesive interactions (if true and depending on other parameters such as Ip2_CohFrictMat_CohFrictMat_CohFrictPhys.setCohesionNow).

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  property maxThickness

    Value of thickness parameter, above which only secondary material parameters are taken into account.

  property minThickness

    Value of thickness parameter, below which only primary material parameters are taken into account.

  property momentRotationLaw

    Use bending/twisting moment at contact. The contact may have moments only if both bodies have this flag true. See Law2_ScGeom6D_CohFrictPhys_CohesionMoment.always_use_moment_law for details.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property normalCohesion

    Tensile strength, homogeneous to a pressure. If negative the normal force is purely elastic.

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property secondaryFrictionAngle

    Friction angle (secondary).

  property secondaryNormalCohesion

    Tensile strength (secondary), homogeneous to a pressure. If negative the normal force is purely elastic.

  property secondaryPoisson

    Poisson’s ratio (secondary) or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property secondaryShearCohesion

    Shear strength (secondary), homogeneous to a pressure. If negative the shear force is purely elastic.

  property secondaryYoung

    elastic modulus (secondary) [Pa]. It has different meanings depending on the Ip functor.

  property shearCohesion

    Shear strength, homogeneous to a pressure. If negative the shear force is purely elastic.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.CohesiveDeformableElementMaterial(inherits Material → Serializable)

  Deformable Element Material.

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.CpmMat(inherits FrictMat → ElastMat → Material → Serializable)

  Concrete material, for use with other Cpm classes.

  Note

  Density is initialized to 4800 kgm⁻³automatically, which gives approximate 2800 kgm⁻³ on 0.5 density packing.

  Concrete Particle Model (CPM)

  CpmMat is particle material, Ip2_CpmMat_CpmMat_CpmPhys averages two particles’ materials, creating CpmPhys, which is then used in interaction resultion by Law2_ScGeom_CpmPhys_Cpm. CpmState is associated to CpmMat and keeps state defined on particles rather than interactions (such as number of completely damaged interactions).

  The model is contained in externally defined macro CPM_MATERIAL_MODEL, which features damage in tension, plasticity in shear and compression and rate-dependence. For commercial reasons, rate-dependence and compression-plasticity is not present in reduced version of the model, used when CPM_MATERIAL_MODEL is not defined. The full model will be described in detail in my (Václav Šmilauer) thesis along with calibration procedures (rigidity, poisson’s ratio, compressive/tensile strength ratio, fracture energy, behavior under confinement, rate-dependent behavior).

  Even the public model is useful enough to run simulation on concrete samples, such as uniaxial tension-compression test.

  property damLaw

    Law for damage evolution in uniaxial tension. 0 for linear stress-strain softening branch, 1 (default) for exponential damage evolution law

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property dmgRateExp

    Exponent for normal viscosity function. [-]

  property dmgTau

    Characteristic time for normal viscosity. [s]

  property epsCrackOnset

    Limit elastic strain [-]

  property equivStrainShearContrib

    Coefficient of shear contribution to equivalent strain

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property isoPrestress

    Isotropic prestress of the whole specimen. [Pa]

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  property neverDamage

    If true, no damage will occur (for testing only).

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property plRateExp

    Exponent for visco-plasticity function. [-]

  property plTau

    Characteristic time for visco-plasticity. [s]

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property relDuctility

    relative ductility of bonds in normal direction

  property sigmaT

    Initial cohesion [Pa]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.DeformableElementMaterial(inherits Material → Serializable)

  Deformable Element Material.

  property density

    Density of the material.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ElastMat(inherits Material → Serializable)

  Purely elastic material. The material parameters may have different meanings depending on the IPhysFunctor used : true Young and Poisson in Ip2_FrictMat_FrictMat_MindlinPhys, or contact stiffnesses in Ip2_FrictMat_FrictMat_FrictPhys.

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.FrictMat(inherits ElastMat → Material → Serializable)

  Elastic material with contact friction. See also ElastMat.

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.FrictMatCDM(inherits FrictMat → ElastMat → Material → Serializable)

  Material to be used for extended Hertz-Mindlin contact law. Normal direction: parameters for Conical Damage Model (Harkness et al. 2016, Suhr & Six 2017). Tangential direction: parameters for stress dependent interparticle friction coefficient (Suhr & Six 2016). Both models can be switched on/off separately.

  property alpha

    [rad] angle of conical asperities, alpha in (0, pi/2)

  property c1

    [-] parameter of pressure dependent friction model c1, choose 0 for constant interparticle friction coefficient

  property c2

    [-] parameter of pressure dependent friction model c2, choose 0 for constant interparticle friction coefficient

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property sigmaMax

    >0 [Pa] max compressive strength of material, choose 1e99 to switch off conical damage model

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.FrictViscoMat(inherits FrictMat → ElastMat → Material → Serializable)

  Material for use with the FrictViscoPM classes

  property betan

    Fraction of the viscous damping coefficient in normal direction equal to \(\frac{c_{n}}{C_{n,crit}}\).

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.InelastCohFrictMat(inherits FrictMat → ElastMat → Material → Serializable)
  property alphaKr

    Dimensionless coefficient used for the rolling stiffness.

  property alphaKtw

    Dimensionless coefficient used for the twist stiffness.

  property compressionModulus

    Compresion elasticity modulus

  property creepBending

    Bending creeping coefficient. Usual values between 0 and 1.

  property creepTension

    Tension/compression creeping coefficient. Usual values between 0 and 1.

  property creepTwist

    Twist creeping coefficient. Usual values between 0 and 1.

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property epsilonMaxCompression

    Maximal plastic strain compression

  property epsilonMaxTension

    Maximal plastic strain tension

  property etaMaxBending

    Maximal plastic bending strain

  property etaMaxTwist

    Maximal plastic twist strain

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property nuBending

    Bending elastic stress limit

  property nuTwist

    Twist elastic stress limit

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property shearCohesion

    Shear elastic stress limit

  property shearModulus

    shear elasticity modulus

  property sigmaCompression

    Compression elastic stress limit

  property sigmaTension

    Tension elastic stress limit

  property tensionModulus

    Tension elasticity modulus

  property unloadBending

    Bending plastic unload coefficient. Usual values between 0 and +infinity.

  property unloadTension

    Tension/compression plastic unload coefficient. Usual values between 0 and +infinity.

  property unloadTwist

    Twist plastic unload coefficient. Usual values between 0 and +infinity.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.JCFpmMat(inherits FrictMat → ElastMat → Material → Serializable)

  Possibly jointed, cohesive frictional material, for use with other JCFpm classes

  property cohesion

    Defines the maximum admissible tangential force in shear, for Fn=0, in the matrix (FsMax = cohesion * crossSection). [Pa]

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property jointCohesion

    Defines the maximum admissible tangential force in shear, for Fn=0, on the joint surface. [Pa]

  property jointDilationAngle

    Defines the dilatancy of the joint surface (only valid for smooth contact logic). [rad]

  property jointFrictionAngle

    Defines Coulomb friction on the joint surface. [rad]

  property jointNormalStiffness

    Defines the normal stiffness on the joint surface. [Pa/m]

  property jointShearStiffness

    Defines the shear stiffness on the joint surface. [Pa/m]

  property jointTensileStrength

    Defines the maximum admissible normal force in traction on the joint surface. [Pa]

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property residualFrictionAngle

    Defines the residual friction angle (when contacts are not cohesive). residualFrictionAngle=frictionAngle if not specified. [rad]

  property tensileStrength

    Defines the maximum admissible normal force in traction in the matrix (FnMax = tensileStrength * crossSection). [Pa]

  property type

    If particles of two different types interact, it will be with friction only (no cohesion).[-]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.LinCohesiveElasticMaterial(inherits CohesiveDeformableElementMaterial → Material → Serializable)

  Linear Isotropic Elastic material

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poissonratio

    Poisson ratio. Initially aluminium.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property youngmodulus

    Young’s modulus. Initially aluminium.

class yade.wrapper.LinCohesiveStiffPropDampElastMat(inherits LinCohesiveElasticMaterial → CohesiveDeformableElementMaterial → Material → Serializable)

  Elastic material with Rayleigh Damping.

  property alpha

    Mass propotional damping constant of Rayleigh Damping.

  property beta

    Stiffness propotional damping constant of Rayleigh Damping.

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poissonratio

    Poisson ratio. Initially aluminium.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property youngmodulus

    Young’s modulus. Initially aluminium.

class yade.wrapper.LinIsoElastMat(inherits DeformableElementMaterial → Material → Serializable)

  Linear Isotropic Elastic material

  property density

    Density of the material.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poissonratio

    Poisson ratio. Initially aluminium.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property youngmodulus

    Young’s modulus. Initially aluminium.

class yade.wrapper.LinIsoRayleighDampElastMat(inherits LinIsoElastMat → DeformableElementMaterial → Material → Serializable)

  Elastic material with Rayleigh Damping.

  property alpha

    Mass propotional damping constant of Rayleigh Damping.

  property beta

    Stiffness propotional damping constant of Rayleigh Damping.

  property density

    Density of the material.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poissonratio

    Poisson ratio. Initially aluminium.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property youngmodulus

    Young’s modulus. Initially aluminium.

class yade.wrapper.LudingMat(inherits Material → Serializable)

  Material for simple Luding`s model of contact [Luding2008] ,[Singh2013]_ .

  property G0

    Viscous damping

  property PhiF

    Dimensionless plasticity depth

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictionAngle

    Friction angle [rad]

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property k1

    Slope of loading plastic branch

  property kc

    Slope of irreversible, tensile adhesive branch

  property kp

    Slope of unloading and reloading limit elastic branch

  property ks

    Shear stiffness

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.MortarMat(inherits FrictMat → ElastMat → Material → Serializable)

  Material for mortar interface, used in Ip2_MortarMat_MortarMat_MortarPhys and Law2_ScGeom_MortarPhys_Lourenco. Default values according to

  property cohesion

    cohesion [Pa]

  property compressiveStrength

    compressiveStrength [Pa]

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property ellAspect

    aspect ratio of elliptical ‘cap’. Value >1 means the ellipse is longer along normal stress axis.

  property frictionAngle

    Friction angle

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  property neverDamage

    If true, interactions remain elastic regardless stresses

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poisson

    Shear to normal modulus ratio

  property tensileStrength

    tensileStrength [Pa]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    Normal elastic modulus [Pa]

class yade.wrapper.ViscElCapMat(inherits ViscElMat → FrictMat → ElastMat → Material → Serializable)

  Material for extended viscoelastic model of contact with capillary parameters.

  property Capillar

    True, if capillar forces need to be added.

  property CapillarType

    Different types of capillar interaction: Willett_numeric, Willett_analytic [Willett2000] , Weigert [Weigert1999] , Rabinovich [Rabinov2005] , Lambert (simplified, corrected Rabinovich model) [Lambert2008]

  property Vb

    Liquid bridge volume [m^3]

  property cn

    Normal viscous constant. Attention, this parameter cannot be set if tc, en or es is defined!

  property cs

    Shear viscous constant. Attention, this parameter cannot be set if tc, en or es is defined!

  property dcap

    Damping coefficient for the capillary phase [-]

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property en

    Restitution coefficient in normal direction

  property et

    Restitution coefficient in tangential direction

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property gamma

    Surface tension [N/m]

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property kn

    Normal elastic stiffness. Attention, this parameter cannot be set if tc, en or es is defined!

  property ks

    Shear elastic stiffness. Attention, this parameter cannot be set if tc, en or es is defined!

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  property lubrication

    option to apply lubrication forces when material is defined from young, poisson and en (restitution coefficient).

  property mR

    Rolling resistance, see [Zhou1999536].

  property mRtype

    Rolling resistance type, see [Zhou1999536]. mRtype=1 - equation (3) in [Zhou1999536]; mRtype=2 - equation (4) in [Zhou1999536].

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property roughnessScale

    if lubrication is activated, roughness scale considered for the particles to evaluate the effective restitution coefficient.

  property tc

    Contact time

  property theta

    Contact angle [°]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property viscoDyn

    if lubrication is activated, surrounding fluid dynamic viscosity considered to evaluate the effective restitution coefficient as a function of the local Stokes number of the collision.

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.ViscElMat(inherits FrictMat → ElastMat → Material → Serializable)

  Material for simple viscoelastic model of contact from analytical solution of a pair spheres interaction problem [Pournin2001] .

  property cn

    Normal viscous constant. Attention, this parameter cannot be set if tc, en or es is defined!

  property cs

    Shear viscous constant. Attention, this parameter cannot be set if tc, en or es is defined!

  property density

    Density of the material [kg/m³]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property en

    Restitution coefficient in normal direction

  property et

    Restitution coefficient in tangential direction

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property kn

    Normal elastic stiffness. Attention, this parameter cannot be set if tc, en or es is defined!

  property ks

    Shear elastic stiffness. Attention, this parameter cannot be set if tc, en or es is defined!

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  property lubrication

    option to apply lubrication forces when material is defined from young, poisson and en (restitution coefficient).

  property mR

    Rolling resistance, see [Zhou1999536].

  property mRtype

    Rolling resistance type, see [Zhou1999536]. mRtype=1 - equation (3) in [Zhou1999536]; mRtype=2 - equation (4) in [Zhou1999536].

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property roughnessScale

    if lubrication is activated, roughness scale considered for the particles to evaluate the effective restitution coefficient.

  property tc

    Contact time

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property viscoDyn

    if lubrication is activated, surrounding fluid dynamic viscosity considered to evaluate the effective restitution coefficient as a function of the local Stokes number of the collision.

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

class yade.wrapper.WireMat(inherits FrictMat → ElastMat → Material → Serializable)

  Material for use with the Wire classes. In conjunction with the corresponding functors it can be used to model steel wire meshes [Thoeni2014], geotextiles [Cheng2016] and more.

  property as

    Cross-section area of a single wire used to transform stress into force. [m²]

  property density

    Density of the material [kg/m³]

  property diameter

    Diameter of the single wire in [m] (the diameter is used to compute the cross-section area of the wire).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Material)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictionAngle

    Contact friction angle (in radians). Hint : use ‘radians(degreesValue)’ in python scripts.

  property id

    Numeric id of this material; is non-negative only if this Material is shared (i.e. in O.materials), -1 otherwise. This value is set automatically when the material is inserted to the simulation via O.materials.append. (This id was necessary since before boost::serialization was used, shared pointers were not tracked properly; it might disappear in the future)

  property isDoubleTwist

    Type of the mesh. If true two particles of the same material which body ids differ by one will be considered as double-twisted interaction.

  property label

    Textual identifier for this material; can be used for shared materials lookup in MaterialContainer.

  property lambdaEps

    Parameter between 0 and 1 to reduce strain at failure of a double-twisted wire (as used by [Bertrand2008]). [-]

  property lambdaF

    Parameter between 0 and 1 introduced by [Thoeni2013] which defines where the shifted force-displacement curve intersects with the new initial stiffness: \(F^*=\lambda_F F_{\text{elastic}}\). [-]

  property lambdak

    Parameter between 0 and 1 to compute the elastic stiffness of a double-twisted wire (as used by [Bertrand2008]): \(k^D=2(\lambda_k k_h + (1-\lambda_k)k^S)\). [-]

  property lambdau

    Parameter between 0 and 1 introduced by [Thoeni2013] which defines the maximum shift of the force-displacement curve in order to take an additional initial elongation (e.g. wire distortion/imperfections, slipping, system flexibility) into account: \(\Delta l^*=\lambda_u l_0 \text{rnd(seed)}\). [-]

  newAssocState((Material)arg1) → State :

    Return new State instance, which is associated with this Material. Some materials have special requirement on Body::state type and calling this function when the body is created will ensure that they match. (This is done automatically if you use utils.sphere, … functions from python).

  property poisson

    Poisson’s ratio or the ratio between shear and normal stiffness [-]. It has different meanings depending on the Ip functor.

  property seed

    Integer used to initialize the random number generator for the calculation of the distortion. If the integer is equal to 0 a internal seed number based on the time is computed. [-]

  property strainStressValues

    Piecewise linear definition of the stress-strain curve by set of points (strain[-]>0,stress[Pa]>0) for one single wire. Tension only is considered and the point (0,0) is not needed! NOTE: Vector needs to be initialized!

  property strainStressValuesDT

    Piecewise linear definition of the stress-strain curve by set of points (strain[-]>0,stress[Pa]>0) for the double twist. Tension only is considered and the point (0,0) is not needed! If this value is given the calculation will be based on two different stress-strain curves without considering the parameter introduced by [Bertrand2008] (see [Thoeni2013]).

  property type

    Three different types are considered:

    0 | Corresponds to Bertrand’s approach (see [Bertrand2008]): only one stress-strain curve is used
    1 | New approach: two separate stress-strain curves can be used (see [Thoeni2013])
    2 | New approach with stochastically distorted contact model: two separate stress-strain curves with changed initial stiffness and horizontal shift (shift is random if \(\text{seed}\geq0\), for more details see [Thoeni2013])

    By default the type is 0.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property young

    elastic modulus [Pa]. It has different meanings depending on the Ip functor.

### Bound

Inheritance graph of Bound.

class yade.wrapper.Bound(inherits Serializable)

  Object bounding part of space taken by associated body; might be larger, used to optimalize collision detection

  property color

    Color for rendering this object

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Bound)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property lastUpdateIter

    record iteration of last reference position update (auto-updated)

  property max

    Upper corner of box containing this bound (and the Body as well)

  property min

    Lower corner of box containing this bound (and the Body as well)

  property refPos

    Reference position, updated at current body position each time the bound dispatcher update bounds (auto-updated)

  property sweepLength

    The length used to increase the bounding boxe size, can be adjusted on the basis of previous displacement if BoundDispatcher::targetInterv>0. (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Aabb(inherits Bound → Serializable)

  Axis-aligned bounding box, for use with InsertionSortCollider. (This class is quasi-redundant since min,max are already contained in Bound itself. That might change at some point, though.)

  property color

    Color for rendering this object

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((Bound)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property lastUpdateIter

    record iteration of last reference position update (auto-updated)

  property max

    Upper corner of box containing this bound (and the Body as well)

  property min

    Lower corner of box containing this bound (and the Body as well)

  property refPos

    Reference position, updated at current body position each time the bound dispatcher update bounds (auto-updated)

  property sweepLength

    The length used to increase the bounding boxe size, can be adjusted on the basis of previous displacement if BoundDispatcher::targetInterv>0. (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

## Interactions

### Interaction

class yade.wrapper.Interaction(inherits Serializable)

  Interaction between pair of bodies.

  property cellDist

    Distance of bodies in cell size units, if using periodic boundary conditions; id2 is shifted by this number of cells from its State::pos coordinates for this interaction to exist. Assigned by the collider.

    Warning

    (internal) cellDist must survive Interaction::reset(), it is only initialized in ctor. Interaction that was cancelled by the constitutive law, was reset() and became only potential must have the period information if the geometric functor again makes it real. Good to know after few days of debugging that :-)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property geom

    Geometry part of the interaction.

  property id1

    Id of the first body in this interaction.

  property id2

    Id of the second body in this interaction.

  property isActive

    True if this interaction is active. Otherwise the forces from this interaction will not be taken into account. True by default.

  property isReal

    True if this interaction has both geom and phys; False otherwise.

  property iterBorn

    Step number at which the interaction was added to simulation.

  property iterMadeReal

    Step number at which the interaction was fully (in the sense of geom and phys) created. (Should be touched only by IPhysDispatcher and InteractionLoop, therefore they are made friends of Interaction

  property phys

    Physical (material) part of the interaction.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### IGeom

Inheritance graph of IGeom.

class yade.wrapper.IGeom(inherits Serializable)

  Geometrical configuration of interaction

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ChCylGeom6D(inherits ScGeom6D → ScGeom → GenericSpheresContact → IGeom → Serializable)

  Test

  property bending

    Bending at contact as a vector defining axis of rotation and angle (angle=norm).

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  incidentVel((ScGeom)arg1, (Interaction)i[, (bool)avoidGranularRatcheting=True]) → yade._minieigenHP.Vector3 :

    Return incident velocity of the interaction (see also Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting for explanation of the ratcheting argument).

  property initialOrientation1

    Orientation of body 1 one at initialisation time (auto-updated)

  property initialOrientation2

    Orientation of body 2 one at initialisation time (auto-updated)

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property penetrationDepth

    Penetration distance of spheres (positive if overlapping)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  relAngVel((ScGeom)arg1, (Interaction)i) → yade._minieigenHP.Vector3 :

    Return relative angular velocity of the interaction.

  property shearInc

    Shear displacement increment in the last step

  property twist

    Elastic twist angle (around normal axis) of the contact.

  property twistCreep

    Stored creep, substracted from total relative rotation for computation of elastic moment (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.CylScGeom(inherits ScGeom → GenericSpheresContact → IGeom → Serializable)

  Geometry of a cylinder-sphere contact.

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property end

    position of 2nd node (auto-updated)

  property id3

    id of next chained cylinder (auto-updated)

  incidentVel((ScGeom)arg1, (Interaction)i[, (bool)avoidGranularRatcheting=True]) → yade._minieigenHP.Vector3 :

    Return incident velocity of the interaction (see also Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting for explanation of the ratcheting argument).

  property isDuplicate

    this flag is turned true (1) automatically if the contact is shared between two chained cylinders. A duplicated interaction will be skipped once by the constitutive law, so that only one contact at a time is effective. If isDuplicate=2, it means one of the two duplicates has no longer geometric interaction, and should be erased by the constitutive laws.

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property onNode

    contact on node?

  property penetrationDepth

    Penetration distance of spheres (positive if overlapping)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  relAngVel((ScGeom)arg1, (Interaction)i) → yade._minieigenHP.Vector3 :

    Return relative angular velocity of the interaction.

  property relPos

    position of the contact on the cylinder (0: node-, 1:node+) (auto-updated)

  property shearInc

    Shear displacement increment in the last step

  property start

    position of 1st node (auto-updated)

  property trueInt

    Defines the body id of the cylinder where the contact is real, when CylScGeom::isDuplicate>0.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.CylScGeom6D(inherits ScGeom6D → ScGeom → GenericSpheresContact → IGeom → Serializable)

  Class representing geometry of two bodies in contact. The contact has 6 DOFs (normal, 2×shear, twist, 2xbending) and uses ScGeom incremental algorithm for updating shear.

  property bending

    Bending at contact as a vector defining axis of rotation and angle (angle=norm).

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property end

    position of 2nd node (auto-updated)

  property id3

    id of next chained cylinder (auto-updated)

  incidentVel((ScGeom)arg1, (Interaction)i[, (bool)avoidGranularRatcheting=True]) → yade._minieigenHP.Vector3 :

    Return incident velocity of the interaction (see also Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting for explanation of the ratcheting argument).

  property initialOrientation1

    Orientation of body 1 one at initialisation time (auto-updated)

  property initialOrientation2

    Orientation of body 2 one at initialisation time (auto-updated)

  property isDuplicate

    this flag is turned true (1) automatically if the contact is shared between two chained cylinders. A duplicated interaction will be skipped once by the constitutive law, so that only one contact at a time is effective. If isDuplicate=2, it means one of the two duplicates has no longer geometric interaction, and should be erased by the constitutive laws.

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property onNode

    contact on node?

  property penetrationDepth

    Penetration distance of spheres (positive if overlapping)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  relAngVel((ScGeom)arg1, (Interaction)i) → yade._minieigenHP.Vector3 :

    Return relative angular velocity of the interaction.

  property relPos

    position of the contact on the cylinder (0: node-, 1:node+) (auto-updated)

  property shearInc

    Shear displacement increment in the last step

  property start

    position of 1st node (auto-updated)

  property trueInt

    Defines the body id of the cylinder where the contact is real, when CylScGeom::isDuplicate>0.

  property twist

    Elastic twist angle (around normal axis) of the contact.

  property twistCreep

    Stored creep, substracted from total relative rotation for computation of elastic moment (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GenericSpheresContact(inherits IGeom → Serializable)

  Class uniting ScGeom and L3Geom, for the purposes of GlobalStiffnessTimeStepper. (It might be removed in the future). Do not use this class directly.

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GridCoGridCoGeom(inherits ScGeom → GenericSpheresContact → IGeom → Serializable)

  Geometry of a GridConnection-GridConnection contact.

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  incidentVel((ScGeom)arg1, (Interaction)i[, (bool)avoidGranularRatcheting=True]) → yade._minieigenHP.Vector3 :

    Return incident velocity of the interaction (see also Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting for explanation of the ratcheting argument).

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property penetrationDepth

    Penetration distance of spheres (positive if overlapping)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  relAngVel((ScGeom)arg1, (Interaction)i) → yade._minieigenHP.Vector3 :

    Return relative angular velocity of the interaction.

  property relPos1

    position of the contact on the first connection (0: node-, 1:node+) (auto-updated)

  property relPos2

    position of the contact on the first connection (0: node-, 1:node+) (auto-updated)

  property shearInc

    Shear displacement increment in the last step

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GridNodeGeom6D(inherits ScGeom6D → ScGeom → GenericSpheresContact → IGeom → Serializable)

  Geometry of a GridNode-GridNode contact. Inherits almost everything from ScGeom6D.

  property bending

    Bending at contact as a vector defining axis of rotation and angle (angle=norm).

  property connectionBody

    Reference to the GridNode Body who is linking the two GridNodes.

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  incidentVel((ScGeom)arg1, (Interaction)i[, (bool)avoidGranularRatcheting=True]) → yade._minieigenHP.Vector3 :

    Return incident velocity of the interaction (see also Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting for explanation of the ratcheting argument).

  property initialOrientation1

    Orientation of body 1 one at initialisation time (auto-updated)

  property initialOrientation2

    Orientation of body 2 one at initialisation time (auto-updated)

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property penetrationDepth

    Penetration distance of spheres (positive if overlapping)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  relAngVel((ScGeom)arg1, (Interaction)i) → yade._minieigenHP.Vector3 :

    Return relative angular velocity of the interaction.

  property shearInc

    Shear displacement increment in the last step

  property twist

    Elastic twist angle (around normal axis) of the contact.

  property twistCreep

    Stored creep, substracted from total relative rotation for computation of elastic moment (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.L3Geom(inherits GenericSpheresContact → IGeom → Serializable)

  Geometry of contact given in local coordinates with 3 degress of freedom: normal and two in shear plane. [experimental]

  property F

    Applied force in local coordinates [debugging only, will be removed]

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  property trsf

    Transformation (rotation) from global to local coordinates. (the translation part is in GenericSpheresContact.contactPoint)

  property u

    Displacement components, in local coordinates. (auto-updated)

  property u0

    Zero displacement value; u0 should be always subtracted from the geometrical displacement u computed by appropriate IGeomFunctor, resulting in u. This value can be changed for instance

    1. by IGeomFunctor, e.g. to take in account large shear displacement value unrepresentable by underlying geomeric algorithm based on quaternions)

    2. by LawFunctor, to account for normal equilibrium position different from zero geometric overlap (set once, just after the interaction is created)

    3. by LawFunctor to account for plastic slip.

    Note

    Never set an absolute value of u0, only increment, since both IGeomFunctor and LawFunctor use it. If you need to keep track of plastic deformation, store it in IPhys isntead (this might be changed: have u0 for LawFunctor exclusively, and a separate value stored (when that is needed) inside classes deriving from L3Geom.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.L6Geom(inherits L3Geom → GenericSpheresContact → IGeom → Serializable)

  Geometric of contact in local coordinates with 6 degrees of freedom. [experimental]

  property F

    Applied force in local coordinates [debugging only, will be removed]

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property phi

    Rotation components, in local coordinates. (auto-updated)

  property phi0

    Zero rotation, should be always subtracted from phi to get the value. See L3Geom.u0.

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  property trsf

    Transformation (rotation) from global to local coordinates. (the translation part is in GenericSpheresContact.contactPoint)

  property u

    Displacement components, in local coordinates. (auto-updated)

  property u0

    Zero displacement value; u0 should be always subtracted from the geometrical displacement u computed by appropriate IGeomFunctor, resulting in u. This value can be changed for instance

    1. by IGeomFunctor, e.g. to take in account large shear displacement value unrepresentable by underlying geomeric algorithm based on quaternions)

    2. by LawFunctor, to account for normal equilibrium position different from zero geometric overlap (set once, just after the interaction is created)

    3. by LawFunctor to account for plastic slip.

    Note

    Never set an absolute value of u0, only increment, since both IGeomFunctor and LawFunctor use it. If you need to keep track of plastic deformation, store it in IPhys isntead (this might be changed: have u0 for LawFunctor exclusively, and a separate value stored (when that is needed) inside classes deriving from L3Geom.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.LSnodeGeom(inherits ScGeom → GenericSpheresContact → IGeom → Serializable)

  Extends ScGeom for faster LevelSet-based simulations of convex bodies while storing previous closest node in surfNodeIdx, for an optimal contact detection.

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  incidentVel((ScGeom)arg1, (Interaction)i[, (bool)avoidGranularRatcheting=True]) → yade._minieigenHP.Vector3 :

    Return incident velocity of the interaction (see also Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting for explanation of the ratcheting argument).

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property penetrationDepth

    Penetration distance of spheres (positive if overlapping)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  relAngVel((ScGeom)arg1, (Interaction)i) → yade._minieigenHP.Vector3 :

    Return relative angular velocity of the interaction.

  property shearInc

    Shear displacement increment in the last step

  property surfNodeIdx

    Index (within surfNodes of id2 if Volume(id1) > Volume(id2); else id1) of the surface node that shows the smallest interparticle distance (overlap or not). A negative value that would be encountered during an actual simulation would mean an inconsistency in implementation.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property usedWorkflow

    Tells for debugging purpose whether this interaction has just (in last Ig2 call) been handled by looping over full nodes because geom was just created (0) or because surfNodeIdx was directly detected as negative (1); or by looping just the neighbor subset (2, desired case), which could itself deteriorate into an additional full loop (3).

class yade.wrapper.MultiScGeom(inherits IGeom → Serializable)

  A set of ScGeom for describing the kinematics of an interaction with multiple contact points between two LevelSet bodies, as a set of ScGeom items in contacts. To combine with MultiFrictPhys and associated classes.

  property contacts

    The actual list of ScGeom items corresponding to the different contact points.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property nodesIds

    List of surface nodes (on id1 if that body is smaller – or equal – in volume, or id2 otherwise) making contacts. Contact point for a node of index nodesIds[i] has kinematic properties stored in contacts[i]. Should be equal to MultiFrictPhys.nodesIds by design

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ScGeom(inherits GenericSpheresContact → IGeom → Serializable)

  Class representing geometry of a contact point between two bodies. It is more general than sphere-sphere contact even though it is primarily focused on spheres contact interactions (reason for the ‘Sc’ naming); it is also used for representing contacts of a Sphere with non-spherical bodies (Facet, Plane, Box, ChainedCylinder), or between two non-spherical bodies (ChainedCylinder). The contact has 3 DOFs (normal and 2×shear) and uses incremental algorithm for updating shear.

  We use symbols \(\vec{x}\), \(\vec{v}\), \(\vec{\omega}\) respectively for position, linear and angular velocities (all in global coordinates) and \(r\) for particles radii; subscripted with 1 or 2 to distinguish 2 spheres in contact. Then we define branch length and unit contact normal

  \[l=||\vec{x}_2-\vec{x}_1||, \vec{n}=\frac{\vec{x}_2-\vec{x}_1}{||\vec{x}_2-\vec{x}_1||}\]

  The relative velocity of the spheres is then

  \[\vec{v}_{12}=\frac{r_1+r_2}{l}(\vec{v}_2-\vec{v}_1) -(r_2 \vec{\omega}_2 + r_1\vec{\omega}_1)\times\vec{n}\]

  where the fraction multiplying translational velocities is to make the definition objective and avoid ratcheting effects (see Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting). The shear component is

  \[\vec{v}_{12}^s=\vec{v}_{12}-(\vec{n}\cdot\vec{v}_{12})\vec{n}.\]

  Tangential displacement increment over last step then reads

  \[\Delta\vec{x}_{12}^s=\Delta t \vec{v}_{12}^s.\]
  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  incidentVel((ScGeom)arg1, (Interaction)i[, (bool)avoidGranularRatcheting=True]) → yade._minieigenHP.Vector3 :

    Return incident velocity of the interaction (see also Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting for explanation of the ratcheting argument).

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property penetrationDepth

    Penetration distance of spheres (positive if overlapping)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  relAngVel((ScGeom)arg1, (Interaction)i) → yade._minieigenHP.Vector3 :

    Return relative angular velocity of the interaction.

  property shearInc

    Shear displacement increment in the last step

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ScGeom6D(inherits ScGeom → GenericSpheresContact → IGeom → Serializable)

  Class representing geometry of two bodies in contact. The contact has 6 DOFs (normal, 2×shear, twist, 2xbending) and uses ScGeom incremental algorithm for updating shear.

  property bending

    Bending at contact as a vector defining axis of rotation and angle (angle=norm).

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  incidentVel((ScGeom)arg1, (Interaction)i[, (bool)avoidGranularRatcheting=True]) → yade._minieigenHP.Vector3 :

    Return incident velocity of the interaction (see also Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting for explanation of the ratcheting argument).

  property initialOrientation1

    Orientation of body 1 one at initialisation time (auto-updated)

  property initialOrientation2

    Orientation of body 2 one at initialisation time (auto-updated)

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property penetrationDepth

    Penetration distance of spheres (positive if overlapping)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  relAngVel((ScGeom)arg1, (Interaction)i) → yade._minieigenHP.Vector3 :

    Return relative angular velocity of the interaction.

  property shearInc

    Shear displacement increment in the last step

  property twist

    Elastic twist angle (around normal axis) of the contact.

  property twistCreep

    Stored creep, substracted from total relative rotation for computation of elastic moment (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ScGridCoGeom(inherits ScGeom6D → ScGeom → GenericSpheresContact → IGeom → Serializable)

  Geometry of a GridConnection-Sphere contact.

  property bending

    Bending at contact as a vector defining axis of rotation and angle (angle=norm).

  property contactPoint

    some reference point for the interaction (usually in the middle). (auto-computed)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property id3

    id of the first GridNode. (auto-updated)

  property id4

    id of the second GridNode. (auto-updated)

  property id5

    id of the third GridNode. (auto-updated)

  incidentVel((ScGeom)arg1, (Interaction)i[, (bool)avoidGranularRatcheting=True]) → yade._minieigenHP.Vector3 :

    Return incident velocity of the interaction (see also Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting for explanation of the ratcheting argument).

  property initialOrientation1

    Orientation of body 1 one at initialisation time (auto-updated)

  property initialOrientation2

    Orientation of body 2 one at initialisation time (auto-updated)

  property isDuplicate

    this flag is turned true (1) automatically if the contact is shared between two Connections. A duplicated interaction will be skipped once by the constitutive law, so that only one contact at a time is effective. If isDuplicate=2, it means one of the two duplicates has no longer geometric interaction, and should be erased by the constitutive laws.

  property normal

    Unit vector oriented along the interaction, from particle #1, towards particle #2. (auto-updated)

  property penetrationDepth

    Penetration distance of spheres (positive if overlapping)

  property refR1

    Reference radius of particle #1. (auto-computed)

  property refR2

    Reference radius of particle #2. (auto-computed)

  relAngVel((ScGeom)arg1, (Interaction)i) → yade._minieigenHP.Vector3 :

    Return relative angular velocity of the interaction.

  property relPos

    position of the contact on the connection (0: node-, 1:node+) (auto-updated)

  property shearInc

    Shear displacement increment in the last step

  property trueInt

    Defines the body id of the GridConnection where the contact is real, when ScGridCoGeom::isDuplicate>0.

  property twist

    Elastic twist angle (around normal axis) of the contact.

  property twistCreep

    Stored creep, substracted from total relative rotation for computation of elastic moment (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property weight

    barycentric coordinates of the projection point (auto-updated)

class yade.wrapper.TTetraGeom(inherits IGeom → Serializable)

  Geometry of interaction between 2 tetrahedra, including volumetric characteristics

  property contactPoint

    Contact point (global coords)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property equivalentCrossSection

    Cross-section of the overlap (perpendicular to the axis of least inertia

  property equivalentPenetrationDepth

    ??

  property maxPenetrationDepthA

    ??

  property maxPenetrationDepthB

    ??

  property normal

    Normal of the interaction, directed in the sense of least inertia of the overlap volume

  property penetrationVolume

    Volume of overlap [m³]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.TTetraSimpleGeom(inherits IGeom → Serializable)

  EXPERIMENTAL. Geometry of interaction between 2 tetrahedra

  property contactPoint

    Contact point (global coords)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property flag

    TODO

  property normal

    Normal of the interaction TODO

  property penetrationVolume

    Volume of overlap [m³]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.VolumeGeom(inherits IGeom → Serializable)

  Geometry of the interaction between two LevelSet bodies when using volume-based interactions. Will soon become the general class for volume interaction, such that it works for polyhedra as well.

  property averagePenetrationDepth

    penetrationVolume / contactArea.

  property contactArea

    Contact area perpendicular to the normal.

  property contactPoint

    Contact point (global coordinates), centroid of the penetration volume.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IGeom)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property normal

    Normal direction of the interaction.

  property orthonormal_axis

  property penetrationVolume

    Volume of the overlap or penetrating region.

  property shearInc

    Shear displacement increment in the last step.

  property twist_axis

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### IPhys

Inheritance graph of IPhys.

class yade.wrapper.IPhys(inherits Serializable)

  Physical (material) properties of interaction.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.BubblePhys(inherits IPhys → Serializable)

  Physics of bubble-bubble interactions, for use with BubbleMat

  property Dmax

    Maximum penetrationDepth of the bubbles before the force displacement curve changes to an artificial exponential curve. Setting this value will have no effect. See Law2_ScGeom_BubblePhys_Bubble::pctMaxForce for more information

  static computeForce((float)arg1, (float)arg2, (float)arg3, (int)arg4, (float)arg5, (float)arg6, (float)arg7, (BubblePhys)arg8) → float :

    Computes the normal force acting between the two interacting bubbles using the Newton-Rhapson method

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property fN

    Contact normal force

  property newtonIter

    Maximum number of force iterations allowed

  property newtonTol

    Convergence criteria for force iterations

  property normalForce

    Normal force

  property rAvg

    Average radius of the two interacting bubbles

  property surfaceTension

    Surface tension of the surrounding liquid

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.CapillaryPhys(inherits FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  Physics (of interaction) for Law2_ScGeom_CapillaryPhys_Capillarity.

  property Delta1

    Defines the surface area wetted by the meniscus on the smallest grains of radius R1 (R1<R2)

  property Delta2

    Defines the surface area wetted by the meniscus on the biggest grains of radius R2 (R1<R2)

  property capillaryPressure

    Value of the capillary pressure Uc. Defined as Ugas-Uliquid, obtained from corresponding Law2 parameter

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property fCap

    Capillary force produced by the presence of the meniscus. This is the force acting on particle #2

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property fusionNumber

    Indicates the number of meniscii that overlap with this one

  property isBroken

    Might be set to true by the user to make liquid bridge inactive (capillary force is zero)

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property meniscus

    True when a meniscus with a non-zero liquid volume (vMeniscus) has been computed for this interaction

  property nn11

    \(\iint_A n_1 n_1 \, dS = \iint_A n_2 n_2 \, dS\), \(A\) being the liquid-gas surface of the meniscus, \(\vec n\) the associated normal, and \((1,2,3)\) a local basis with \(3\) the meniscus orientation (ScGeom.normal). NB: \(A\) = 2 nn11 + nn33.

  property nn33

    \(\iint_A n_3 n_3 \, dS\), \(A\) being the liquid-gas surface of the meniscus, \(\vec n\) the associated normal, and \((1,2,3)\) a local basis with \(3\) the meniscus orientation (ScGeom.normal). NB: \(A\) = 2 nn11 + nn33.

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vMeniscus

    Volume of the meniscus

class yade.wrapper.CohFrictPhys(inherits RotStiffFrictPhys → FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  An interaction physics that extends RotStiffFrictPhys adding a breakable cohesive nature. Used e.g. by Law2_ScGeom6D_CohFrictPhys_CohesionMoment.

  property cohesionBroken

    is cohesion active? Set to false at the creation of a cohesive contact, and set to true when a fragile contact is broken

  property cohesionDisablesFriction

    is shear strength the sum of friction and adhesion or only adhesion?

  property creep_viscosity

    creep viscosity [Pa.s/m].

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property fragile

    do cohesion disappear when contact strength is exceeded?

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property initCohesion

    Initialize the cohesive behaviour with current state as equilibrium state (same as Ip2_CohFrictMat_CohFrictMat_CohFrictPhys::setCohesionNow but acting on only one interaction)

  property kn

    Normal stiffness

  property kr

    rotational stiffness [N.m/rad]

  property ks

    Shear stiffness

  property ktw

    twist stiffness [N.m/rad]

  property maxRollPl

    Coefficient of rolling friction (negative means elastic).

  property maxTwistPl

    Coefficient of twisting friction (negative means elastic).

  property momentRotationLaw

    set from CohFrictMat::momentRotationLaw in order to possibly use bending/twisting moment at contacts (if true). See Law2_ScGeom6D_CohFrictPhys_CohesionMoment::always_use_moment_law for details.

  property moment_bending

    Bending moment

  property moment_twist

    Twist moment

  property normalAdhesion

    tensile strength

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property rollingAdhesion

    maximum bending moment when normal force is null (a frictional term might be added depending on CohFrictPhys::cohesionDisablesFriction and CohFrictPhys::maxRollPl)

  property shearAdhesion

    cohesive part of the shear strength (a frictional term might be added depending on CohFrictPhys::cohesionDisablesFriction)

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  property twistingAdhesion

    maximum twisting moment when normal force is null (a frictional term might be added depending on CohFrictPhys::cohesionDisablesFriction and CohFrictPhys::maxTwistPl)

  property unp

    plastic normal displacement, only used for tensile behaviour and if CohFrictPhys::fragile =false.

  property unpMax

    maximum value of plastic normal displacement (counted positively), after that the interaction breaks even if CohFrictPhys::fragile =false. A negative value (i.e. -1) means no maximum.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.CpmPhys(inherits NormShearPhys → NormPhys → IPhys → Serializable)

  Representation of a single interaction of the Cpm type: storage for relevant parameters.

  Evolution of the contact is governed by Law2_ScGeom_CpmPhys_Cpm, that includes damage effects and chages of parameters inside CpmPhys. See cpm-model for details.

  property E

    normal modulus (stiffness / crossSection) [Pa]

  property Fn

    Magnitude of normal force (auto-updated)

  property Fs

    Magnitude of shear force (auto-updated)

  property G

    shear modulus [Pa]

  property crossSection

    equivalent cross-section associated with this contact [m²]

  cummBetaCount = 0
  cummBetaIter = 0
  property damLaw

    Law for softening part of uniaxial tension. 0 for linear, 1 for exponential (default)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property dmgOverstress

    damage viscous overstress (at previous step or at current step)

  property dmgRateExp

    exponent in the rate-dependent damage evolution

  property dmgStrain

    damage strain (at previous or current step)

  property dmgTau

    characteristic time for damage (if non-positive, the law without rate-dependence is used)

  property epsCrackOnset

    strain at which the material starts to behave non-linearly

  property epsFracture

    strain at which the bond is fully broken [-]

  property epsN

    Current normal strain (auto-updated)

  property epsNPl

    normal plastic strain (initially zero) (auto-updated)

  property epsT

    Current shear strain (auto-updated)

  property epsTPl

    shear plastic strain (initially zero) (auto-updated)

  property equivStrainShearContrib

    Coefficient of shear contribution to equivalent strain

  static funcG((float)kappaD, (float)epsCrackOnset, (float)epsFracture[, (bool)neverDamage=False[, (int)damLaw=1]]) → float :

    Damage evolution law, evaluating the \(\omega\) parameter. \(\kappa_D\) is historically maximum strain, epsCrackOnset (\(\varepsilon_0\)) = CpmPhys.epsCrackOnset, epsFracture = CpmPhys.epsFracture; if neverDamage is `True`, the value returned will always be 0 (no damage). TODO

  static funcGInv((float)omega, (float)epsCrackOnset, (float)epsFracture[, (bool)neverDamage=False[, (int)damLaw=1]]) → float :

    Inversion of damage evolution law, evaluating the \(\kappa_D\) parameter. \(\omega\) is damage, for other parameters see funcG function

  property isCohesive

    if not cohesive, interaction is deleted when distance is greater than zero.

  property isoPrestress

    “prestress” of this link (used to simulate isotropic stress)

  property kappaD

    Up to now maximum normal strain (semi-norm), non-decreasing in time (auto-updated)

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property neverDamage

    the damage evolution function will always return virgin state

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property omega

    Damage internal variable (auto-updated)

  property plRateExp

    exponent in the rate-dependent viscoplasticity

  property plTau

    characteristic time for viscoplasticity (if non-positive, no rate-dependence for shear)

  property refLength

    initial length of interaction [m]

  property refPD

    initial penetration depth of interaction [m] (used with ScGeom)

  property relDuctility

    Relative ductility of bonds in normal direction

  property relResidualStrength

    Relative residual strength (auto-updated)

  setDamage((CpmPhys)arg1, (float)arg2) → None :

    TODO

  setRelResidualStrength((CpmPhys)arg1, (float)arg2) → None :

    TODO

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property sigmaN

    Current normal stress (auto-updated)

  property sigmaT

    Current shear stress (auto-updated)

  property tanFrictionAngle

    tangens of internal friction angle [-]

  property undamagedCohesion

    virgin material cohesion [Pa]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.FrictPhys(inherits NormShearPhys → NormPhys → IPhys → Serializable)

  The simple linear elastic-plastic interaction with friction angle, like in the traditional [CundallStrack1979]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.FrictViscoPhys(inherits FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  Representation of a single interaction of the FrictViscoPM type, storage for relevant parameters

  property cn

    Normal viscous constant defined as \(\c_{n}=c_{n,crit}\beta_n\).

  property cn_crit

    Normal viscous constant for ctitical damping defined as \(\c_{n}=C_{n,crit}\beta_n\).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property normalViscous

    Normal viscous component

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.InelastCohFrictPhys(inherits RotStiffFrictPhys → FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)
  property cohesionBroken

    is cohesion active? will be set false when a fragile contact is broken

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property isBroken

    true if compression plastic fracture achieved

  property kDam

    Damage coefficient on bending, computed from maximum bending moment reached and pure creep behaviour. Its values will vary between InelastCohFrictPhys::kr and InelastCohFrictPhys::kRCrp .

  property kRCrp

    Bending creep stiffness

  property kRUnld

    Bending plastic unload stiffness

  property kTCrp

    Tension/compression creep stiffness

  property kTUnld

    Tension/compression plastic unload stiffness

  property kTwCrp

    Twist creep stiffness

  property kTwUnld

    Twist plastic unload stiffness

  property kn

    Normal stiffness

  property knC

    compression stiffness

  property knT

    tension stiffness

  property kr

    rotational stiffness [N.m/rad]

  property ks

    shear stiffness

  property ktw

    twist stiffness [N.m/rad]

  property maxBendMom

    Plastic failure bending moment.

  property maxContract

    Plastic failure contraction (shrinkage).

  property maxCrpRchdB

    maximal bending moment reached on plastic deformation.

  property maxCrpRchdC

    maximal compression reached on plastic deformation. maxCrpRchdC[0] stores un and maxCrpRchdC[1] stores Fn.

  property maxCrpRchdT

    maximal extension reached on plastic deformation. maxCrpRchdT[0] stores un and maxCrpRchdT[1] stores Fn.

  property maxCrpRchdTw

    maximal twist reached on plastic deformation. maxCrpRchdTw[0] stores twist angle and maxCrpRchdTw[1] stores twist moment.

  property maxElB

    Maximum bending elastic moment.

  property maxElC

    Maximum compression elastic force.

  property maxElT

    Maximum tension elastic force.

  property maxElTw

    Maximum twist elastic moment.

  property maxExten

    Plastic failure extension (stretching).

  property maxTwist

    Plastic failure twist angle

  property moment_bending

    Bending moment

  property moment_twist

    Twist moment

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property onPlastB

    true if plasticity achieved on bending

  property onPlastC

    true if plasticity achieved on compression

  property onPlastT

    true if plasticity achieved on traction

  property onPlastTw

    true if plasticity achieved on twisting

  property pureCreep

    Pure creep curve, used for comparison in calculation.

  property shearAdhesion

    Maximum elastic shear force (cohesion).

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  property twp

    plastic twist penetration depth describing the equilibrium state.

  property unp

    plastic normal penetration depth describing the equilibrium state.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.JCFpmPhys(inherits NormShearPhys → NormPhys → IPhys → Serializable)

  Representation of a single interaction of the JCFpm type, storage for relevant parameters

  property FnMax

    positiv value computed from tensile strength (or joint variant) to define the maximum admissible normal force in traction: Fn >= -FnMax. [N]

  property FsMax

    computed from cohesion (or jointCohesion) to define the maximum admissible tangential force in shear, for Fn=0. [N]

  property checkedForCluster

    Have we checked if this int belongs in cluster?

  property clusterInts

    vector of pointers to the broken interactions nearby constituting a cluster

  property clusteredEvent

    is this interaction part of a cluster?

  property computedCentroid

    Flag for moment calculation

  property crackJointAperture

    Relative displacement between 2 spheres (in case of a crack it is equivalent of the crack aperture)

  property crossSection

    crossSection=pi*Rmin^2. [m2]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property dilation

    defines the normal displacement in the joint after sliding treshold. [m]

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property elapsedIter

    number of elapsed iterations for moment calculation

  property eventBeginTime

    The time at which event initiated

  property eventNumber

    cluster event number

  property firstMomentCalc

    Flag for moment calculation (auto-updated)

  property initD

    equilibrium distance for interacting particles. Computed as the interparticular distance at first contact detection.

  property interactionsAdded

    have we added the ints associated with this event?

  property isBroken

    flag for broken interactions

  property isCohesive

    If false, particles interact in a frictional way. If true, particles are bonded regarding the given cohesion and tensile strength (or their jointed variants).

  property isOnJoint

    defined as true when both interacting particles are on joint and are in opposite sides of the joint surface. In this case, mechanical parameters of the interaction are derived from the ‘’joint…’’ material properties of the particles. Furthermore, the normal of the interaction may be re-oriented (see Law2_ScGeom_JCFpmPhys_JointedCohesiveFrictionalPM.smoothJoint).

  property isOnSlot

    defined as true when interaction is located in the perforation slot (surface).

  property jointCumulativeSliding

    sliding distance for particles interacting on a joint. Used, when is true, to take into account dilatancy due to shearing. [-]

  property jointNormal

    normal direction to the joint, deduced from e.g. .

  property kineticEnergy

    kinetic energy of the two spheres participating in the interaction (easiest to store this value with interaction instead of spheres since we are using this information for moment magnitude estimations and associated interaction searches)

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property momentBroken

    Flag for moment calculation

  property momentCalculated

    Flag for moment calculation to avoid repeating twice the operations (auto-updated)

  property momentCentroid

    centroid of the AE event (avg location of clustered breaks)

  property momentEnergy

    reference strain (or kinetic) energy of surrounding interactions (particles)

  property momentEnergyChange

    storage of the maximum strain (or kinetic) energy change for surrounding interactions (particles)

  property momentMagnitude

    Moment magnitude of a failed interaction

  property more

    specifies if the interaction is crossed by more than 3 joints. If true, interaction is deleted (temporary solution).

  property nearbyFound

    Count used to debug moment calc

  property nearbyInts

    vector of pointers to the nearby ints used for moment calc

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property originalClusterEvent

    the original AE event for a cluster

  property originalEvent

    pointer to the original interaction of a cluster

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property strainEnergy

    strain energy of interaction

  property tanDilationAngle

    tangent of the angle defining the dilatancy of the joint surface (auto. computed from JCFpmMat.jointDilationAngle). [-]

  property tanFrictionAngle

    tangent of Coulomb friction angle for this interaction (auto. computed). [-]

  property temporalWindow

    temporal window for the clustering algorithm

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.KnKsPhys(inherits FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  EXPERIMENTAL. IPhys for PotentialParticle.

  property brittleLength

    Shear length where strength degrades, not fully in use

  property cohesion

    Cohesion

  property cohesionBroken

    Whether cohesion is already broken. Considered true for particles with isBoundary=True

  property contactArea

    Contact area (auto-updated)

  property cumulative_us

    Cumulative shear translation (not fully in use)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property effective_phi

    Friction angle in clay after displacement

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property frictionAngle

    Friction angle

  property initialShearDir

    Initial shear direction

  property intactRock

    Whether to consider cohesive force in the Mohr-Coulomb criterion, if allowBreakage=False and cohesionBroken=False.

  property isSliding

    Check if the contact is sliding (useful to calculate the ratio of sliding contacts)

  property jointLength

    Approximated contact length

  property jointType

    jointType

  property kn

    Normal stiffness

  property knVol

    Volumetric normal stiffness = Knormal

  property kn_i

    Currently, we assume kn_i and Knormal are adopting the same value in Ip2 initialisation

  property ks

    Shear stiffness

  property ksVol

    Volumetric shear stiffness = Kshear

  property ks_i

    Currently, we assume ks_i and Kshear are adopting the same value in Ip2 initialisation

  property maxClosure

    not fully in use, vmi

  property mobilizedShear

    Percentage of mobilized shear force as the ratio of the current shear force to the current frictional limit. Represents a quantified measure of the isSliding parameter

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property normalViscous

    Viscous normal force

  property phi_b

    Basic friction angle (degrees)

  property phi_r

    Residual friction angle (degrees)

  property prevNormal

    Previous normal

  property prevSigma

    Previous normal stress

  property ptOnP1

    Point on particle 1

  property ptOnP2

    Point on particle 2

  property shearDir

    Shear direction

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearIncrementForCD

    toSeeWhether it is necessary to update contactArea

  property shearViscous

    Viscous shear force (assumed zero at the moment)

  property tangensOfFrictionAngle

    tan of angle of friction

  property tension

    Tension

  property tensionBroken

    Whether tension is already broken. Considered true for particles with isBoundary=True

  property u_cumulative

    Cumulative translation

  property u_elastic

    Elastic shear displacement, not fully in use

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property useFaceProperties

    Whether to get face properties from the intersecting particles

  property viscousDamping

    Viscous damping ratio, taken equal to Ip2_FrictMat_FrictMat_KnKsPhys.viscousDamping

  property warmstart

    Warmstart for SOCP, not fully in use

class yade.wrapper.LubricationPhys(inherits ViscElPhys → FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  IPhys class for Lubrication w/o FlowEngine. Used by Law2_ScGeom_ImplicitLubricationPhys.

  property Fn

    Linear-elastic part of the normal force of the contact

  property Fv

    Viscous part of the normal force of the contact

  property a

    Mean radius [m]

  property cn

    Normal viscous constant

  property contact

    The spheres are in contact

  property cs

    Shear viscous constant

  property delta

    \(\log(u)\) - used for scheme with \(\delta=\log(u)\) variable change

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property eps

    Roughness: fraction of radius used as roughness [-]

  property eta

    Fluid viscosity [Pa.s]

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property keps

    stiffness coefficient of the asperities [N/m]. Only used with resolution method=0, with resolution>0 it is always equal to kn.

  property kn

    Normal stiffness

  property kno

    Coefficient for normal stiffness (Hertzian-like contact) [N/m^(3/2)]

  property ks

    Shear stiffness

  property mR

    Rolling resistance, see [Zhou1999536].

  property mRtype

    Rolling resistance type, see [Zhou1999536]. mRtype=1 - equation (3) in [Zhou1999536]; mRtype=2 - equation (4) in [Zhou1999536]

  property mum

    Friction coefficient [-]

  property normalContactForce

    Normal contact force [N]

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property normalLubricationForce

    Normal lubrication force [N]

  property normalPotentialForce

    Normal force from potential other than contact [N]

  property nun

    Coefficient for normal lubrication [N.s]

  property prevDotU

    du/dt from previous integration - used for trapezoidal scheme (see Law2_ScGeom_ImplicitLubricationPhys::resolution for choosing resolution scheme)

  property prev_un

    Nondeformed distance (un) at t-dt [m]

  property shearContactForce

    Frictional contact force [N]

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearLubricationForce

    Shear lubrication force [N]

  property slip

    The contact is slipping

  property tangensOfFrictionAngle

    tan of angle of friction

  property u

    Interfacial distance (u) at t-dt [m]

  property ue

    Surface deflection (ue) at t-dt [m]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.LudingPhys(inherits FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  IPhys created from LudingMat, for use with Law2_ScGeom_LudingPhys_Basic.

  property DeltMax

    Maximum overlap between particles for a collision

  property DeltMin

    MinimalDelta value of delta

  property DeltNull

    Force free overlap, plastic contact deformation

  property DeltPMax

    Maximum overlap between particles for the limit case

  property DeltPNull

    Max force free overlap, plastic contact deformation

  property DeltPrev

    Previous value of delta

  property G0

    Viscous damping

  property PhiF

    Dimensionless plasticity depth

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property k1

    Slope of loading plastic branch

  property k2

    Slope of unloading and reloading elastic branch

  property kc

    Slope of irreversible, tensile adhesive branch

  property kn

    Normal stiffness

  property kp

    Slope of unloading and reloading limit elastic branch

  property ks

    Shear stiffness

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.MindlinCapillaryPhys(inherits MindlinPhys → RotStiffFrictPhys → FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  Adds capillary physics to Mindlin’s interaction physics.

  property Delta1

    Defines the surface area wetted by the meniscus on the smallest grains of radius R1 (R1<R2)

  property Delta2

    Defines the surface area wetted by the meniscus on the biggest grains of radius R2 (R1<R2)

  property Fs

    Shear force in local axes (computed incrementally)

  property adhesionForce

    Force of adhesion as predicted by DMT

  property beta

    Auxiliary parameter used in the viscous damping model of [Mueller2011]

  property betan

    Normal Damping Ratio. Fraction of the viscous damping coefficient (normal direction) equal to \(\frac{c_{n}}{C_{n,crit}}\).

  property betas

    Shear Damping Ratio. Fraction of the viscous damping coefficient (shear direction) equal to \(\frac{c_{s}}{C_{s,crit}}\).

  property capillaryPressure

    Value of the capillary pressure Uc. Defined as Ugas-Uliquid, obtained from corresponding Law2 parameter

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property fCap

    Capillary Force produces by the presence of the meniscus. This is the force acting on particle #2

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property fusionNumber

    Indicates the number of meniscii that overlap with this one

  property isAdhesive

    bool to identify if the contact is adhesive, that is to say if the contact force is attractive

  property isBroken

    Might be set to true by the user to make liquid bridge inactive (capillary force is zero)

  property isSliding

    check if the contact is sliding (useful to calculate the ratio of sliding contacts)

  property kn

    Normal stiffness

  property kno

    Constant value in the formulation of the normal stiffness

  property kr

    rotational stiffness [N.m/rad]

  property ks

    Shear stiffness

  property kso

    Constant value in the formulation of the tangential stiffness

  property ktw

    twist stiffness [N.m/rad]

  property maxBendPl

    Coefficient to determine the maximum plastic moment to apply at the contact

  property meniscus

    True when a meniscus with a non-zero liquid volume (vMeniscus) has been computed for this interaction

  property momentBend

    Artificial bending moment to provide rolling resistance in order to account for some degree of interlocking between particles

  property momentTwist

    Artificial twisting moment (no plastic condition can be applied at the moment)

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property normalViscous

    Normal viscous component

  property prevU

    Previous local displacement; only used with Law2_L3Geom_FrictPhys_HertzMindlin.

  property radius

    Contact radius (only computed with Law2_ScGeom_MindlinPhys_Mindlin::calcEnergy)

  property shearElastic

    Total elastic shear force

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearViscous

    Shear viscous component

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property usElastic

    Total elastic shear displacement (only elastic part)

  property usTotal

    Total elastic shear displacement (elastic+plastic part)

  property vMeniscus

    Volume of the meniscus

class yade.wrapper.MindlinPhys(inherits RotStiffFrictPhys → FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  Representation of an interaction of the Hertz-Mindlin type.

  property Fs

    Shear force in local axes (computed incrementally)

  property adhesionForce

    Force of adhesion as predicted by DMT

  property beta

    Auxiliary parameter used in the viscous damping model of [Mueller2011]

  property betan

    Normal Damping Ratio. Fraction of the viscous damping coefficient (normal direction) equal to \(\frac{c_{n}}{C_{n,crit}}\).

  property betas

    Shear Damping Ratio. Fraction of the viscous damping coefficient (shear direction) equal to \(\frac{c_{s}}{C_{s,crit}}\).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property isAdhesive

    bool to identify if the contact is adhesive, that is to say if the contact force is attractive

  property isSliding

    check if the contact is sliding (useful to calculate the ratio of sliding contacts)

  property kn

    Normal stiffness

  property kno

    Constant value in the formulation of the normal stiffness

  property kr

    rotational stiffness [N.m/rad]

  property ks

    Shear stiffness

  property kso

    Constant value in the formulation of the tangential stiffness

  property ktw

    twist stiffness [N.m/rad]

  property maxBendPl

    Coefficient to determine the maximum plastic moment to apply at the contact

  property momentBend

    Artificial bending moment to provide rolling resistance in order to account for some degree of interlocking between particles

  property momentTwist

    Artificial twisting moment (no plastic condition can be applied at the moment)

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property normalViscous

    Normal viscous component

  property prevU

    Previous local displacement; only used with Law2_L3Geom_FrictPhys_HertzMindlin.

  property radius

    Contact radius (only computed with Law2_ScGeom_MindlinPhys_Mindlin::calcEnergy)

  property shearElastic

    Total elastic shear force

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearViscous

    Shear viscous component

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property usElastic

    Total elastic shear displacement (only elastic part)

  property usTotal

    Total elastic shear displacement (elastic+plastic part)

class yade.wrapper.MindlinPhysCDM(inherits MindlinPhys → RotStiffFrictPhys → FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  Representation of an interaction of an extended Hertz-Mindlin type. Normal direction: parameters for Conical Damage Model (Harkness et al. 2016, Suhr & Six 2017). Tangential direction: parameters for stress dependent interparticle friction coefficient (Suhr & Six 2016). Both models can be switched on/off separately, see FrictMatCDM.

  property E

    [Pa] equiv. Young’s modulus

  property Fs

    Shear force in local axes (computed incrementally)

  property G

    [Pa] equiv. shear modulus

  property R

    [m] contact radius in conical damage model

  property adhesionForce

    Force of adhesion as predicted by DMT

  property alphaFac

    factor considering angle of conical asperities

  property beta

    Auxiliary parameter used in the viscous damping model of [Mueller2011]

  property betan

    Normal Damping Ratio. Fraction of the viscous damping coefficient (normal direction) equal to \(\frac{c_{n}}{C_{n,crit}}\).

  property betas

    Shear Damping Ratio. Fraction of the viscous damping coefficient (shear direction) equal to \(\frac{c_{s}}{C_{s,crit}}\).

  property c1

    [-] parameter of pressure dependent friction model c1

  property c2

    [-] parameter of pressure dependent friction model c2

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property isAdhesive

    bool to identify if the contact is adhesive, that is to say if the contact force is attractive

  property isSliding

    check if the contact is sliding (useful to calculate the ratio of sliding contacts)

  property isYielding

    bool: is contact currently yielding?

  property kn

    Normal stiffness

  property kno

    Constant value in the formulation of the normal stiffness

  property kr

    rotational stiffness [N.m/rad]

  property ks

    Shear stiffness

  property kso

    Constant value in the formulation of the tangential stiffness

  property ktw

    twist stiffness [N.m/rad]

  property maxBendPl

    Coefficient to determine the maximum plastic moment to apply at the contact

  property momentBend

    Artificial bending moment to provide rolling resistance in order to account for some degree of interlocking between particles

  property momentTwist

    Artificial twisting moment (no plastic condition can be applied at the moment)

  property mu0

    [-] parameter of pressure dependent friction model mu0

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property normalViscous

    Normal viscous component

  property prevU

    Previous local displacement; only used with Law2_L3Geom_FrictPhys_HertzMindlin.

  property radius

    Contact radius (only computed with Law2_ScGeom_MindlinPhys_Mindlin::calcEnergy)

  property shearElastic

    Total elastic shear force

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearViscous

    Shear viscous component

  property sigmaMax

    [Pa] max compressive strength of material

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property usElastic

    Total elastic shear displacement (only elastic part)

  property usTotal

    Total elastic shear displacement (elastic+plastic part)

class yade.wrapper.MortarPhys(inherits FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  IPhys class containing parameters of MortarMat. Used by Law2_ScGeom_MortarPhys_Lourenco.

  property cohesion

    cohesion [Pa]

  property compressiveStrength

    compressiveStrength [Pa]

  property crossSection

    Crosssection of interaction

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property ellAspect

    aspect ratio of elliptical ‘cap’. Value >1 means the ellipse is longer along normal stress axis.

  failureCondition((MortarPhys)arg1, (float)arg2, (float)arg3) → bool :

    Failure condition from normal stress and norm of shear stress (false=elastic, true=damaged)

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property neverDamage

    If true, interactions remain elastic regardless stresses

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property sigmaN

    Current normal stress (auto-updated)

  property sigmaT

    Current shear stress (auto-updated)

  property tangensOfFrictionAngle

    tan of angle of friction

  property tensileStrength

    tensileStrength [Pa]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.MultiFrictPhys(inherits MultiPhys → IPhys → Serializable)

  Describes the physical part of an interaction with multiple frictional contact points, e.g., between two LevelSet bodies, through a set of FrictPhys instances in contacts. To combine with MultiScGeom and associated classes.

  property contacts

    The actual list of IPhys (for the mother class, actually obtained types can be different for derived classes such as MultiFrictPhys which will include FrictPhys instances) items corresponding to the different contact points.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property nodesIds

    The physics counterpart of MultiScGeom.nodesIds (both should be equal by design).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.MultiPhys(inherits IPhys → Serializable)

  Describes the physical part of an interaction with multiple contact points, e.g., between two LevelSet bodies, as a set of IPhys items. This class is actually not intended to be used directly but to serve as a common ancestor for children classes such as MultiFrictPhys.

  property contacts

    The actual list of IPhys (for the mother class, actually obtained types can be different for derived classes such as MultiFrictPhys which will include FrictPhys instances) items corresponding to the different contact points.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property nodesIds

    The physics counterpart of MultiScGeom.nodesIds (both should be equal by design).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.MultiViscElPhys(inherits MultiPhys → IPhys → Serializable)

  Describes the physical part of an interaction with multiple viscoelastic frictional contact points, e.g., between two LevelSet bodies, through a set of ViscElPhys instances in contacts. To combine with MultiScGeom and associated classes.

  property contacts

    The actual list of IPhys (for the mother class, actually obtained types can be different for derived classes such as MultiFrictPhys which will include FrictPhys instances) items corresponding to the different contact points.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property nodesIds

    The physics counterpart of MultiScGeom.nodesIds (both should be equal by design).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.NormPhys(inherits IPhys → Serializable)

  Abstract class for interactions that have normal stiffness.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property kn

    Normal stiffness

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.NormShearPhys(inherits NormPhys → IPhys → Serializable)

  Abstract class for interactions that have shear stiffnesses, in addition to normal stiffness. This class is used in the PFC3d-style stiffness timestepper.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.RotStiffFrictPhys(inherits FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  Version of FrictPhys with a rotational stiffness

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property kn

    Normal stiffness

  property kr

    rotational stiffness [N.m/rad]

  property ks

    Shear stiffness

  property ktw

    twist stiffness [N.m/rad]

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ViscElCapPhys(inherits ViscElPhys → FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  IPhys created from ViscElCapMat, for use with Law2_ScGeom_ViscElCapPhys_Basic.

  property Capillar

    True, if capillar forces need to be added.

  property CapillarType

    Different types of capillar interaction: Willett_numeric, Willett_analytic, Weigert, Rabinovich, Lambert, Soulie

  property Fn

    Linear-elastic part of the normal force of the contact

  property Fv

    Viscous part of the normal force of the contact

  property Vb

    Liquid bridge volume [m^3]

  property cn

    Normal viscous constant

  property cs

    Shear viscous constant

  property dcap

    Damping coefficient for the capillary phase [-]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property gamma

    Surface tension [N/m]

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property liqBridgeActive

    Whether liquid bridge is active at the moment

  property liqBridgeCreated

    Whether liquid bridge was created, only after a normal contact of spheres

  property mR

    Rolling resistance, see [Zhou1999536].

  property mRtype

    Rolling resistance type, see [Zhou1999536]. mRtype=1 - equation (3) in [Zhou1999536]; mRtype=2 - equation (4) in [Zhou1999536]

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property sCrit

    Critical bridge length [m]

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  property theta

    Contact angle [rad]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ViscElPhys(inherits FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  IPhys created from ViscElMat, for use with Law2_ScGeom_ViscElPhys_Basic.

  property Fn

    Linear-elastic part of the normal force of the contact

  property Fv

    Viscous part of the normal force of the contact

  property cn

    Normal viscous constant

  property cs

    Shear viscous constant

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property mR

    Rolling resistance, see [Zhou1999536].

  property mRtype

    Rolling resistance type, see [Zhou1999536]. mRtype=1 - equation (3) in [Zhou1999536]; mRtype=2 - equation (4) in [Zhou1999536]

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ViscoFrictPhys(inherits FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  Temporary version of FrictPhys for compatibility reasons

  property creepedShear

    Creeped force (parallel)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.WirePhys(inherits FrictPhys → NormShearPhys → NormPhys → IPhys → Serializable)

  Representation of a single interaction of the WirePM type, storage for relevant parameters

  property dL

    Additional wire length for considering the distortion for WireMat type=2 (see [Thoeni2013]).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispHierarchy((IPhys)arg1[, (bool)names=True]) → list :

    Return list of dispatch classes (from down upwards), starting with the class instance itself, top-level indexable at last. If names is true (default), return class names rather than numerical indices.

  property dispIndex

    Return class index of this instance.

  property displForceValues

    Defines the values for force-displacement curve.

  property frictDissip

    frictional energy dissipation in the contact (this value is updated by contact laws applicable to FrictPhys - currently only Law2_ScGeom_FrictPhys_CundallStrack) (auto-updated)

  property initD

    Equilibrium distance for particles. Computed as the initial inter-particular distance when particle are linked.

  property isDoubleTwist

    If true the properties of the interaction will be defined as a double-twisted wire.

  property isLinked

    If true particles are linked and will interact. Interactions are linked automatically by the definition of the corresponding interaction radius. The value is false if the wire breaks (no more interaction).

  property isShifted

    If true WireMat type=2 and the force-displacement curve will be shifted.

  property kn

    Normal stiffness

  property ks

    Shear stiffness

  property limitFactor

    This value indicates on how far from failing the wire is, e.g. actual normal displacement divided by admissible normal displacement.

  property normalForce

    Normal force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property plastD

    Plastic part of the inter-particular distance of the previous step.

    Note

    Only elastic displacements are reversible (the elastic stiffness is used for unloading) and compressive forces are inadmissible. The compressive stiffness is assumed to be equal to zero.

  property shearForce

    Shear force after previous step (in global coordinates), as sustained by particle #2 (from particle #1).

  property stiffnessValues

    Defines the values for the various stiffnesses (the elastic stiffness is stored as kn).

  property tangensOfFrictionAngle

    tan of angle of friction

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

## Global engines

### GlobalEngine

Inheritance graph of GlobalEngine, gray dashed classes are discussed in their own sections: BoundaryController, PeriodicEngine, FieldApplier, Collider.

class yade.wrapper.GlobalEngine(inherits Engine → Serializable)

  Engine that will generally affect the whole simulation (contrary to PartialEngine).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.BoxFactory(inherits SpheresFactory → GlobalEngine → Engine → Serializable)

  Box geometry of the SpheresFactory region, given by extents and center

  property PSDcalculateMass

    PSD-Input is in mass (true), otherwise the number of particles will be considered.

  property PSDcum

    PSD-dispersion, cumulative procent meanings [-]

  property PSDsizes

    PSD-dispersion, sizes of cells, Diameter [m]

  property blockedDOFs

    Blocked degress of freedom

  property center

    Center of the region

  property color

    Use the color for newly created particles, if specified

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property exactDiam

    If true, the particles only with the defined in PSDsizes diameters will be created. Otherwise the diameter will be randomly chosen in the range [PSDsizes[i-1]:PSDsizes[i]], in this case the length of PSDsizes should be more on 1, than the length of PSDcum.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property extents

    Extents of the region

  property goalMass

    Total mass that should be attained at the end of the current step. (auto-updated)

  property ids

    ids of created bodies

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mask

    groupMask to apply for newly created spheres

  property massFlowRate

    Mass flow rate [kg/s]

  property materialId

    Shared material id to use for newly created spheres (can be negative to count from the end)

  property maxAttempt

    Maximum number of attempts to position a new sphere randomly.

  property maxMass

    Maximal mass at which to stop generating new particles regardless of massFlowRate. if maxMass=-1 - this parameter is ignored.

  property maxParticles

    The number of particles at which to stop generating new ones regardless of massFlowRate. if maxParticles=-1 - this parameter is ignored .

  property normal

    Orientation of the region’s geometry, direction of particle’s velocites if normalVel is not set.

  property normalVel

    Direction of particle’s velocites.

  property numParticles

    Cummulative number of particles produces so far (auto-updated)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property rMax

    Maximum radius of generated spheres (uniform distribution)

  property rMin

    Minimum radius of generated spheres (uniform distribution)

  property silent

    If true no complain about excessing maxAttempt but disable the factory (by set massFlowRate=0).

  property stopIfFailed

    If true, the SpheresFactory stops (sets massFlowRate=0), when maximal number of attempts to insert particle exceed.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property totalMass

    Mass of spheres that was produced so far. (auto-updated)

  property totalVolume

    Volume of spheres that was produced so far. (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vAngle

    Maximum angle by which the initial sphere velocity deviates from the normal.

  property vMax

    Maximum velocity norm of generated spheres (uniform distribution)

  property vMin

    Minimum velocity norm of generated spheres (uniform distribution)

class yade.wrapper.CircularFactory(inherits SpheresFactory → GlobalEngine → Engine → Serializable)

  Circular geometry of the SpheresFactory region. It can be disk (given by radius and center), or cylinder (given by radius, length and center).

  property PSDcalculateMass

    PSD-Input is in mass (true), otherwise the number of particles will be considered.

  property PSDcum

    PSD-dispersion, cumulative procent meanings [-]

  property PSDsizes

    PSD-dispersion, sizes of cells, Diameter [m]

  property blockedDOFs

    Blocked degress of freedom

  property center

    Center of the region

  property color

    Use the color for newly created particles, if specified

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property exactDiam

    If true, the particles only with the defined in PSDsizes diameters will be created. Otherwise the diameter will be randomly chosen in the range [PSDsizes[i-1]:PSDsizes[i]], in this case the length of PSDsizes should be more on 1, than the length of PSDcum.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property goalMass

    Total mass that should be attained at the end of the current step. (auto-updated)

  property ids

    ids of created bodies

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property length

    Length of the cylindrical region (0 by default)

  property mask

    groupMask to apply for newly created spheres

  property massFlowRate

    Mass flow rate [kg/s]

  property materialId

    Shared material id to use for newly created spheres (can be negative to count from the end)

  property maxAttempt

    Maximum number of attempts to position a new sphere randomly.

  property maxMass

    Maximal mass at which to stop generating new particles regardless of massFlowRate. if maxMass=-1 - this parameter is ignored.

  property maxParticles

    The number of particles at which to stop generating new ones regardless of massFlowRate. if maxParticles=-1 - this parameter is ignored .

  property normal

    Orientation of the region’s geometry, direction of particle’s velocites if normalVel is not set.

  property normalVel

    Direction of particle’s velocites.

  property numParticles

    Cummulative number of particles produces so far (auto-updated)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property rMax

    Maximum radius of generated spheres (uniform distribution)

  property rMin

    Minimum radius of generated spheres (uniform distribution)

  property radius

    Radius of the region

  property silent

    If true no complain about excessing maxAttempt but disable the factory (by set massFlowRate=0).

  property stopIfFailed

    If true, the SpheresFactory stops (sets massFlowRate=0), when maximal number of attempts to insert particle exceed.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property totalMass

    Mass of spheres that was produced so far. (auto-updated)

  property totalVolume

    Volume of spheres that was produced so far. (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vAngle

    Maximum angle by which the initial sphere velocity deviates from the normal.

  property vMax

    Maximum velocity norm of generated spheres (uniform distribution)

  property vMin

    Minimum velocity norm of generated spheres (uniform distribution)

class yade.wrapper.CohesiveFrictionalContactLaw(inherits GlobalEngine → Engine → Serializable)

  [DEPRECATED] Loop over interactions applying Law2_ScGeom6D_CohFrictPhys_CohesionMoment on all interactions.

  Note

  Use InteractionLoop and Law2_ScGeom6D_CohFrictPhys_CohesionMoment instead of this class for performance reasons.

  property always_use_moment_law

    If false, compute moments only for cohesive contacts, broken contacts will have only normal and shear forces. If true, compute bending/twisting moments at all contacts and use the frictional coefficients CohFrictMat::etaRoll and CohFrictMat::etaTwist to define the strength of the broken contacts.

  property creep_viscosity

    creep viscosity [Pa.s/m]. probably should be moved to Ip2_CohFrictMat_CohFrictMat_CohFrictPhys…

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property shear_creep

    activate creep on the shear force, using CohesiveFrictionalContactLaw::creep_viscosity.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property twist_creep

    activate creep on the twisting moment, using CohesiveFrictionalContactLaw::creep_viscosity.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ElasticContactLaw(inherits GlobalEngine → Engine → Serializable)

  [DEPRECATED] Loop over interactions applying Law2_ScGeom_FrictPhys_CundallStrack on all interactions.

  Note

  Use InteractionLoop and Law2_ScGeom_FrictPhys_CundallStrack instead of this class for performance reasons.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.FEInternalForceEngine(inherits GlobalEngine → Engine → Serializable)

  Unified dispatcher for handling Finite Element internal force loop at every step, for parallel performance reasons.

  Special constructor

  Constructs from 3 lists of Ig2, Ip2, Law functors respectively; they will be passed to interal dispatchers, which you might retrieve.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property internalforcedispatcher

    InternalForceDispatcher object that is used for dispatching of element types.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.FacetTopologyAnalyzer(inherits GlobalEngine → Engine → Serializable)

  Initializer for filling adjacency geometry data for facets.

  Common vertices and common edges are identified and mutual angle between facet faces is written to Facet instances. If facets don’t move with respect to each other, this must be done only at the beginng.

  property commonEdgesFound

    how many common edges were identified during last run. (auto-updated)

  property commonVerticesFound

    how many common vertices were identified during last run. (auto-updated)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property projectionAxis

    Axis along which to do the initial vertex sort

  property relTolerance

    maximum distance of ‘identical’ vertices, relative to minimum facet size

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.FoamCoupling(inherits GlobalEngine → Engine → Serializable)
  An engine for coupling Yade with the finite volume fluid solver OpenFOAM in parallel.

    Requirements : Yade compiled with MPI libs, OpenFOAM-6 (openfoam is not required for compilation).Yade is executed under MPI environment with OpenFOAM simultaneously, and using MPI communication routines data is exchanged between the solvers.

    1. Yade broadcasts the particle data -> position, velocity, ang-velocity, radius to all the foam processes as in castParticle

  2. In each foam process, particle is searched.Yade keeps a vector(cpp) of the rank of the openfoam process containing that particular particle (FoamCoupling::procList), using updateProcList

  3. In simple lagrangian point force coupling Yade recieves the particle hydrodynamic force and torque from the openfoam process, the sender is identified from the vector FoamCoupling::procList. In the case of Gaussian interpolation, contribution from every process is summed using function sumHydroForce . 4. The interval (substepping) is set automatically (FoamCoupling::dataExchangeInterval) based on dtfoam/dtYade, calculated in function exchangeDeltaT

  SetOpenFoamSolver((FoamCoupling)arg1, (str)OpenFOAMSolverName, (int)numOpenFOAMProcesses) → None :

    Starts the Yade coupled OpenFOAM solver with the requested number of processes

  StartFoamSolver((FoamCoupling)arg1) → None :

    Starts the OpenFOAM solver

  property comm

    Communicator to be used for MPI (converts mpi4py comm <-> c++ comm)

  property dataExchangeInterval

    Number of iterations/substepping : for stability and to be in sync with fluid solver calculated in exchangeDeltaT

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  eraseId((FoamCoupling)arg1, (int)idToErase) → bool :

    remove a body from hydrodynamic force coupling

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property fluidDensity

    fluidDensity

  property fluidDomains

    list of fluid domain bounding fictitious fluid bodies that has the fluid mesh bounds

  property foamDeltaT

    timestep in openfoam solver from exchangeDeltaT

  property foamPath

    path to OpenFoam

  property foamVersion

    version of OpenFoam environment

  getFluidDomainBbox((FoamCoupling)arg1) → None :

    get the fluid domain bounding boxes, called once during simulation initialization.

  getIdList((FoamCoupling)arg1) → object :

    get the ids of bodies in coupling

  getNumBodies((FoamCoupling)arg1) → int :

    get the number of bodies in the coupling

  insertBodyId((FoamCoupling)arg1, (int)newId) → None :

    insert a new body id for hydrodynamic force coupling

  property isGaussianInterp

    switch for Gaussian interpolation of field varibles in openfoam. Uses sumHydroForce to obtain hydrodynamic force

  killMPI((FoamCoupling)arg1) → None :

    Destroy MPI, to be called at the end of the simulation, from killMPI

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property numParticles

    number of particles in coupling.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property particleDensity

    particle Density

  setIdList((FoamCoupling)arg1, (object)bodyIdlist) → None :

    list of body ids in hydroForce coupling. (links to :yref: FoamCoupling::bodyList vector, used to build particle data FoamCoupling::particleData. FoamCoupling::particleData contains the particle pos, vel, angvel, radius and this is sent to foam. )

  setNumParticles((FoamCoupling)arg1, (int)numparticles) → None :

    number of particles in coupling

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ForceResetter(inherits GlobalEngine → Engine → Serializable)

  Reset all forces stored in Scene::forces (`O.forces` in python). Typically, this is the first engine to be run at every step. In addition, reset those energies that should be reset, if energy tracing is enabled.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GlobalStiffnessTimeStepper(inherits TimeStepper → GlobalEngine → Engine → Serializable)

  An engine assigning the time-step as a fraction of the minimum eigen-period in the problem. The derivation is detailed in the chapter on DEM formulation. The viscEl option enables to evaluate the timestep in a similar way for the visco-elastic contact law Law2_ScGeom_ViscElPhys_Basic, more detail in GlobalStiffnessTimestepper::viscEl.

  property active

    is the engine active?

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  property defaultDt

    used as the initial value of the timestep (especially useful in the first steps when no contact exist). If negative, it will be defined by utils.PWaveTimeStep * GlobalStiffnessTimeStepper::timestepSafetyCoefficient

  property densityScaling

    (auto-updated) don’t modify this value if you don’t plan to modify the scaling factor manually for some bodies. In most cases, it is enough to set NewtonIntegrator::densityScaling and let this one be adjusted automatically.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxDt

    if positive, used as max value of the timestep whatever the computed value

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property parallelMode

    if parallelMode, dt is set to min of all subdomain dt.

  property previousDt

    last computed dt (auto-updated)

  property targetDt

    if NewtonIntegrator::densityScaling is active, this value will be used as the simulation timestep and a mass density scaling will use this value of dt as the target value. The value of targetDt is arbitrary and should have no effect in the result in general. However if some bodies have imposed velocities, for instance, they will move more or less per each step depending on this value.

  property timeStepUpdateInterval

    dt update interval

  property timestepSafetyCoefficient

    safety factor between the minimum eigen-period and the final assigned dt (less than 1)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property viscEl

    To use with ViscElPhys. if True, evaluate separetly the minimum eigen-period in the problem considering only the elastic contribution on one hand (spring only), and only the viscous contribution on the other hand (dashpot only). Take then the minimum of the two and use the safety coefficient GlobalStiffnessTimestepper::timestepSafetyCoefficient to take into account the possible coupling between the two contribution.

class yade.wrapper.HydrodynamicsLawLBM(inherits GlobalEngine → Engine → Serializable)

  Engine to simulate fluid flow (with the lattice Boltzmann method) with a coupling with the discrete element method. If you use this Engine, please cite and refer to F. Lominé et al. International Journal For Numerical and Analytical Method in Geomechanics, 2012, doi: 10.1002/nag.1109

  property ConvergenceThreshold

  property CstBodyForce

    A constant body force (=that does not vary in time or space, otherwise the implementation introduces errors)

  property DemIterLbmIterRatio

    Ratio between DEM and LBM iterations for subcycling

  property EndTime

    the time to stop the simulation

  property EngineIsActivated

    To activate (or not) the engine

  property IterMax

    This variable can be used to do several LBM iterations during one DEM iteration.

  property IterPrint

    Print info on screen every IterPrint iterations

  property IterSave

    Data are saved every IterSave LBM iteration (or see TimeSave)

  property IterSubCyclingStart

    Iteration number when the subcycling process starts

  property LBMSavedData

    a list of data that will be saved. Can use velocity,velXY,forces,rho,bodies,nodeBD,newNode,observedptc,observednode,contacts,spheres,bz2

  property Nu

    Fluid kinematic viscosity

  property Nx

    The number of grid division in x direction

  property ObservedNode

    The identifier of the node that will be observed (-1 means none)

  property ObservedPtc

    The identifier of the particle that will be observed (-1 means the first one)

  property RadFactor

    The radius of DEM particules seen by the LBM is the real radius of particules*RadFactor

  property Rho

    Fluid density

  property SaveGridRatio

    Grid data are saved every SaveGridRatio * IterSave LBM iteration (with SaveMode=1)

  property SaveMode

    Save Mode (1-> default, 2-> in time (not yet implemented)

  property TimeSave

    Data are saved at constant time interval (or see IterSave)

  property VbCutOff

    the minimum boundary velocity that is taken into account

  property VelocityThreshold

    Velocity threshold when removingCriterion=2

  property WallXm_id

    Identifier of the X- wall

  property WallXp_id

    Identifier of the X+ wall

  property WallYm_id

    Identifier of the Y- wall

  property WallYp_id

    Identifier of the Y+ wall

  property WallZm_id

    Identifier of the Z- wall

  property WallZp_id

    Identifier of the Z+ wall

  property XmBCType

    Boundary condition for the wall in Xm (-1: unused, 1: pressure condition, 2: velocity condition).

  property XmBcRho

    (!!! not fully implemented !!) The density imposed at the boundary

  property XmBcVel

    (!!! not fully implemented !!) The velocity imposed at the boundary

  property XmYmZmBCType

    Boundary condition for the corner node XmYmZm (not used with d2q9, -1: unused, 1: pressure condition, 2: velocity condition).

  property XmYmZpBCType

    Boundary condition for the corner node XmYmZp (-1: unused, 1: pressure condition, 2: velocity condition).

  property XmYpZmBCType

    Boundary condition for the corner node XmYpZm (not used with d2q9, -1: unused, 1: pressure condition, 2: velocity condition).

  property XmYpZpBCType

    Boundary condition for the corner node XmYpZp (-1: unused, 1: pressure condition, 2: velocity condition).

  property XpBCType

    Boundary condition for the wall in Xp (-1: unused, 1: pressure condition, 2: velocity condition).

  property XpBcRho

    (!!! not fully implemented !!) The density imposed at the boundary

  property XpBcVel

    (!!! not fully implemented !!) The velocity imposed at the boundary

  property XpYmZmBCType

    Boundary condition for the corner node XpYmZm (not used with d2q9, -1: unused, 1: pressure condition, 2: velocity condition).

  property XpYmZpBCType

    Boundary condition for the corner node XpYmZp (-1: unused, 1: pressure condition, 2: velocity condition).

  property XpYpZmBCType

    Boundary condition for the corner node XpYpZm (not used with d2q9, -1: unused, 1: pressure condition, 2: velocity condition).

  property XpYpZpBCType

    Boundary condition for the corner node XpYpZp (-1: unused, 1: pressure condition, 2: velocity condition).

  property YmBCType

    Boundary condition for the wall in Ym (-1: unused, 1: pressure condition, 2: velocity condition).

  property YmBcRho

    (!!! not fully implemented !!) The density imposed at the boundary

  property YmBcVel

    (!!! not fully implemented !!) The velocity imposed at the boundary

  property YpBCType

    Boundary condition for the wall in Yp (-1: unused, 1: pressure condition, 2: velocity condition).

  property YpBcRho

    (!!! not fully implemented !!) The density imposed at the boundary

  property YpBcVel

    (!!! not fully implemented !!) The velocity imposed at the boundary

  property ZmBCType

    Boundary condition for the wall in Zm (-1: unused, 1: pressure condition, 2: velocity condition).

  property ZmBcRho

    (!!! not fully implemented !!) The density imposed at the boundary

  property ZmBcVel

    (!!! not fully implemented !!) The velocity imposed at the boundary

  property ZpBCType

    Boundary condition for the wall in Zp (-1: unused, 1: pressure condition, 2: velocity condition).

  property ZpBcVel

    (!!! not fully implemented !!) The velocity imposed at the boundary

  property applyForcesAndTorques

    Switch to apply forces and torques

  property bc

    Boundary condition

  property dP

    Pressure difference between input and output

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  property defaultLbmInitMode

    Switch between the two initialisation methods

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property model

    The LB model. Until now only d2q9 is implemented

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property periodicity

    periodicity

  property removingCriterion

    Criterion to remove a sphere (1->based on particle position, 2->based on particle velocity

  property tau

    Relaxation time

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property useWallXm

    Set true if you want that the LBM see the wall in Xm

  property useWallXp

    Set true if you want that the LBM see the wall in Xp

  property useWallYm

    Set true if you want that the LBM see the wall in Ym

  property useWallYp

    Set true if you want that the LBM see the wall in Yp

  property useWallZm

    Set true if you want that the LBM see the wall in Zm

  property useWallZp

    Set true if you want that the LBM see the wall in Zp

  property zpBcRho

    (!!! not fully implemented !!) The density imposed at the boundary

class yade.wrapper.Integrator(inherits TimeStepper → GlobalEngine → Engine → Serializable)

  Integration Engine Interface.

  property active

    is the engine active?

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property integrationsteps

    all integrationsteps count as all succesfull substeps

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxVelocitySq

    store square of max. velocity, for informative purposes; computed again at every step. (auto-updated)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property slaves

    List of lists of Engines to calculate the force acting on the particles; to obtain the derivatives of the states, engines inside will be run sequentially.

  property timeStepUpdateInterval

    dt update interval

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.InteractionLoop(inherits GlobalEngine → Engine → Serializable)

  Unified dispatcher for handling interaction loop at every step, for parallel performance reasons.

  Special constructor

  Constructs from 3 lists of Ig2, Ip2, Law2 functors respectively; they will be passed to internal dispatchers, which you might retrieve as geomDispatcher, physDispatcher, lawDispatcher respectively.

  property callbacks

    Callbacks which will be called for every Interaction, if activated.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property geomDispatcher

    IGeomDispatcher object that is used for dispatch.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property lawDispatcher

    LawDispatcher object used for dispatch.

  property loopOnSortedInteractions

    If true, the main interaction loop will occur on a sorted list of interactions. This is SLOW but useful to workaround floating point force addition non reproducibility when debugging parallel implementations of yade.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property physDispatcher

    IPhysDispatcher object used for dispatch.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property warnRoleIg2

    Whether warnings are output (if true) in case the IGeomFunctor would directly request for interaction removal (by returning false in its ::go function) on existing interactions. It is advised to use false only in the specific case of using Ig2_LevelSet_LevelSet_LSnodeGeom, and true otherwise.

class yade.wrapper.Law2_ScGeom_CapillaryPhys_Capillarity(inherits GlobalEngine → Engine → Serializable)

  This engine allows one to take into account capillary forces/effects between spheres coming from the presence of distinct interparticular liquid bridges (menisci) at existing interactions (between particle pairs, in the so-called pendular regime). In order to allow capillary forces between distant spheres, it is necessary to enlarge the bounding boxes using Bo1_Sphere_Aabb::aabbEnlargeFactor and make the Ig2 define define distant interactions via interactionDetectionFactor. See also createDistantMeniscii. It is also necessary to disable interactions removal by the constitutive law (Law2). The only combinations of laws supported are currently capillary law + Law2_ScGeom_FrictPhys_CundallStrack and capillary law + Law2_ScGeom_MindlinPhys_Mindlin (and the other variants of Hertz-Mindlin)

  The control parameter for simulating liquid bridges is the capillary pressure (or suction) Uc = Ugas - Uliquid. Liquid bridges properties (volume V, extent over interacting grains delta1 and delta2) are computed as a result of the defined capillary pressure and of the interacting geometry (spheres radii and interparticular distance). For this purpose, ascii files M(r=i) with i=R1/R2 (and a possible suffix) are required, containing a set of results from the resolution of the Laplace-Young equation for different configurations of the interacting geometry, and can be downloaded from yade-data/capillaryFiles (direct download here) for the case of a null wetting angle. They could also be regenerated, possibly for other conditions, by any user as per point II. in examples/capillaryLaplaceYoung/README.md.

  See examples/capillaryLaplaceYoung/ folder for example scripts.

  References: in english [Scholtes2009b] [Duriez2017b]; more detailed, but in french [Scholtes2009d].

  property binaryFusion

    If true, capillary forces are set to zero as soon as, at least, 1 overlap (menisci fusion) is detected. Otherwise fCap = fCap / (fusionNumber + 1 ) (experimental)

  property capillaryPressure

    Value of the capillary pressure Uc defined as Uc=Ugas-Uliquid

  property createDistantMeniscii

    Generate meniscii between distant spheres ? Else only maintain the existing ones. For modeling a wetting path this flag should always be false. For a drying path it should be true for one step (initialization) then false, as in the logic of [Scholtes2009c]. The engine turns it off automatically after one execution.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property fusionDetection

    If true potential menisci overlaps are checked, computing fusionNumber for each capillary interaction, and reducing fCap according to binaryFusion

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property suffCapFiles

    Capillary files suffix: M(r=X)suffCapFiles

  property surfaceTension

    Value of considered surface tension

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.NewtonIntegrator(inherits GlobalEngine → Engine → Serializable)

  Engine integrating newtonian motion equations, see Motion integration for some theoretical background.

  property dampGravity

    By default, numerical damping applies to ALL forces, even gravity. If this option is set to false, then the gravity forces calculated based on NewtonIntegrator.gravity are excluded from the damping calculation. This option has no effect on gravity forces added by GravityEngine.

  property damping

    damping coefficient for Cundall’s non viscous damping (see Numerical damping and [Chareyre2005])

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  property densityScaling

    if True, then density scaling [Pfc3dManual30] will be applied in order to have a critical timestep equal to GlobalStiffnessTimeStepper::targetDt for all bodies. This option makes the simulation unrealistic from a dynamic point of view, but may speedup quasistatic simulations. In rare situations, it could be useful to not set the scalling factor automatically for each body (which the time-stepper does). In such case revert GlobalStiffnessTimeStepper.densityScaling to False.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property exactAsphericalRot

    Enable more exact body rotation integrator for aspherical bodies only, using formulations from [delValle2023], [Omelyan1998], or [Fincham1992] depending on rotAlgorithm

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property gravity

    Gravitational acceleration (effectively replaces GravityEngine).

  property kinSplit

    Whether to separately track translational and rotational kinetic energy.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mask

    If mask defined and the bitwise AND between mask and body`s groupMask gives 0, the body will not move/rotate. Velocities and accelerations will be calculated not paying attention to this parameter.

  property maxVelocitySq

    stores max. displacement, based on which we trigger collision detection. (auto-updated)

  property niterOmelyan1998

    The number of iterations used to solve the nonlinear system of [Omelyan1998] formulation in case the latter is chosen as a rotational integration algorithm. Provided a small enough timestep, three iterations are enough to make the system converge.

  property normalizeEvery

    Normalize the quaternion every normalizeEvery step. Only used in the aspherical formulations from [delValle2023], [Omelyan1998].

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property prevVelGrad

    Store previous velocity gradient (Cell::velGrad) to track average acceleration in periodic simulations. (auto-updated)

  property rotAlgorithm

    Which rotation algorithm to use. Options are: ‘delValle2023’, ‘Omelyan1998’, ‘Fincham1992’. The choice also impacts the expected ways for defining initial angular velocities, if any, see Initial (angular) velocity.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property warnNoForceReset

    Warn when forces were not resetted in this step by ForceResetter; this mostly points to ForceResetter being forgotten incidentally and should be disabled only with a good reason.

class yade.wrapper.RungeKuttaCashKarp54Integrator(inherits Integrator → TimeStepper → GlobalEngine → Engine → Serializable)

  RungeKuttaCashKarp54Integrator engine.

  __init__((object)arg1) → None

    object __init__(tuple args, dict kwds)

    __init__( (object)arg1, (list)arg2) -> object :

      Construct from (possibly nested) list of slaves.

  property a_dxdt

  property a_x

  property abs_err

    Relative integration tolerance

  property active

    is the engine active?

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property integrationsteps

    all integrationsteps count as all succesfull substeps

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxVelocitySq

    store square of max. velocity, for informative purposes; computed again at every step. (auto-updated)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property rel_err

    Absolute integration tolerance

  property slaves

    List of lists of Engines to calculate the force acting on the particles; to obtain the derivatives of the states, engines inside will be run sequentially.

  property stepsize

    It is not important for an adaptive integration but important for the observer for setting the found states after integration

  property timeStepUpdateInterval

    dt update interval

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.SpheresFactory(inherits GlobalEngine → Engine → Serializable)

  Engine for spitting spheres based on mass flow rate, particle size distribution etc. Initial velocity of particles is given by vMin, vMax, the massFlowRate determines how many particles to generate at each step. When goalMass is attained or positive maxParticles is reached, the engine does not produce particles anymore. Geometry of the region should be defined in a derived engine by overridden SpheresFactory::pickRandomPosition().

  A sample script for this engine is in scripts/spheresFactory.py.

  property PSDcalculateMass

    PSD-Input is in mass (true), otherwise the number of particles will be considered.

  property PSDcum

    PSD-dispersion, cumulative procent meanings [-]

  property PSDsizes

    PSD-dispersion, sizes of cells, Diameter [m]

  property blockedDOFs

    Blocked degress of freedom

  property color

    Use the color for newly created particles, if specified

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property exactDiam

    If true, the particles only with the defined in PSDsizes diameters will be created. Otherwise the diameter will be randomly chosen in the range [PSDsizes[i-1]:PSDsizes[i]], in this case the length of PSDsizes should be more on 1, than the length of PSDcum.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property goalMass

    Total mass that should be attained at the end of the current step. (auto-updated)

  property ids

    ids of created bodies

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mask

    groupMask to apply for newly created spheres

  property massFlowRate

    Mass flow rate [kg/s]

  property materialId

    Shared material id to use for newly created spheres (can be negative to count from the end)

  property maxAttempt

    Maximum number of attempts to position a new sphere randomly.

  property maxMass

    Maximal mass at which to stop generating new particles regardless of massFlowRate. if maxMass=-1 - this parameter is ignored.

  property maxParticles

    The number of particles at which to stop generating new ones regardless of massFlowRate. if maxParticles=-1 - this parameter is ignored .

  property normal

    Orientation of the region’s geometry, direction of particle’s velocites if normalVel is not set.

  property normalVel

    Direction of particle’s velocites.

  property numParticles

    Cummulative number of particles produces so far (auto-updated)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property rMax

    Maximum radius of generated spheres (uniform distribution)

  property rMin

    Minimum radius of generated spheres (uniform distribution)

  property silent

    If true no complain about excessing maxAttempt but disable the factory (by set massFlowRate=0).

  property stopIfFailed

    If true, the SpheresFactory stops (sets massFlowRate=0), when maximal number of attempts to insert particle exceed.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property totalMass

    Mass of spheres that was produced so far. (auto-updated)

  property totalVolume

    Volume of spheres that was produced so far. (auto-updated)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vAngle

    Maximum angle by which the initial sphere velocity deviates from the normal.

  property vMax

    Maximum velocity norm of generated spheres (uniform distribution)

  property vMin

    Minimum velocity norm of generated spheres (uniform distribution)

class yade.wrapper.TetraVolumetricLaw(inherits GlobalEngine → Engine → Serializable)

  Calculate physical response of 2 tetrahedra in interaction, based on penetration configuration given by TTetraGeom.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.TimeStepper(inherits GlobalEngine → Engine → Serializable)

  Engine defining time-step (fundamental class)

  property active

    is the engine active?

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timeStepUpdateInterval

    dt update interval

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### PeriodicEngine

Inheritance graph of PeriodicEngine.

class yade.wrapper.PeriodicEngine(inherits GlobalEngine → Engine → Serializable)

  Run Engine::action with given fixed periodicity real time (=wall clock time, computation time), virtual time (simulation time), iteration number), by setting any of those criteria (virtPeriod, realPeriod, iterPeriod) to a positive value. They are all negative (inactive) by default.

  The number of times this engine is activated can be limited by setting nDo>0. If the number of activations will have been already reached, no action will be called even if an active period has elapsed.

  If initRun is set (false by default), the engine will run when called for the first time; otherwise it will only start counting period (realLast, etc, interval variables) from that point, but without actually running, and will run only once a period has elapsed since the initial run.

  This class should not be used directly; rather, derive your own engine which you want to be run periodically.

  Derived engines should override Engine::action(), which will be called periodically. If the derived Engine overrides also Engine::isActivated, it should also take in account return value from PeriodicEngine::isActivated, since otherwise the periodicity will not be functional.

  Example with PyRunner, which derives from PeriodicEngine; likely to be encountered in python scripts:

      PyRunner(realPeriod=5,iterPeriod=10000,command='print O.iter')

  will print iteration number every 10000 iterations or every 5 seconds of wall clock time, whichever comes first since it was last run.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.CapillaryStressRecorder(inherits Recorder → PeriodicEngine → GlobalEngine → Engine → Serializable)

  Records information from capillary meniscii on samples submitted to triaxial compressions. Classical sign convention (tension positiv) is used for capillary stresses. -> New formalism needs to be tested!!!

  property addIterNum

    Adds an iteration number to the file name, when the file was created. Useful for creating new files at each call (false by default)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property file

    Name of file to save to; must not be empty.

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property truncate

    Whether to delete current file contents, if any, when opening (false by default)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.CpmStateUpdater(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Update CpmState of bodies based on state variables in CpmPhys of interactions with this bod. In particular, bodies’ colors and CpmState::normDmg depending on average damage of their interactions and number of interactions that were already fully broken and have disappeared is updated. This engine contains its own loop (2 loops, more precisely) over all bodies and should be run periodically to update colors during the simulation, if desired.

  property avgRelResidual

    Average residual strength at last run.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxOmega

    Globally maximum damage parameter at last run.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.DomainLimiter(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Delete particles that are out of axis-aligned box given by lo and hi.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property hi

    Upper corner of the domain.

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property lo

    Lower corner of the domain.

  property mDeleted

    Mass of deleted particles.

  property mask

    If mask is defined, only particles with corresponding groupMask will be deleted.

  property nDeleted

    Cummulative number of particles deleted.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vDeleted

    Volume of deleted spheres (clumps not counted, in that case check mDeleted)

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.ForceRecorder(inherits Recorder → PeriodicEngine → GlobalEngine → Engine → Serializable)

  Engine saves the resultant force affecting to bodies, listed in ids. For instance, can be useful for defining the forces, which affects to _buldozer_ during its work.

  property addIterNum

    Adds an iteration number to the file name, when the file was created. Useful for creating new files at each call (false by default)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property file

    Name of file to save to; must not be empty.

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property ids

    List of bodies whose state will be measured

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property totalForce

    Resultant force, returning by the function.

  property truncate

    Whether to delete current file contents, if any, when opening (false by default)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.LubricationPDFEngine(inherits PDFEngine → PeriodicEngine → GlobalEngine → Engine → Serializable)

  Implementation of PDFEngine for Lubrication law

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property filename

    Filename

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property numDiscretizeAnglePhi

    Number of sector for phi-angle

  property numDiscretizeAngleTheta

    Number of sector for theta-angle

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

  property warnedOnce

    For one-time warning. May trigger usefull warnings

class yade.wrapper.MeasureCapStress(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Post-processing engine giving the capillary stress tensor (the fluids mixture contribution to the total stress in unsaturated, i.e. triphasic, conditions) according to the \(\mu\)UNSAT expression detailled in [Duriez2017c]. Although this expression differs in nature from the one of utils.getCapillaryStress (consideration of distributed integrals herein, vs resultant capillary force therein), both are equivalent [Duriez2016b], [Duriez2017], [Duriez2017c]. The REV volume \(V\) entering the expression is automatically measured, from the Cell for periodic conditions, or from utils.aabbExtrema function otherwise.

  property capillaryPressure

    Capillary pressure \(u_c\), to be defined equal to Law2_ScGeom_CapillaryPhys_Capillarity.capillaryPressure.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  property debug

    To output some debugging messages.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property muGamma

    Tensorial contribution to sigmaCap from the contact lines \(\Gamma\): \(\boldsymbol{\mu_{\Gamma}} = \int_{\Gamma} \vec \nu_{nw} \otimes \vec x \, dl\) with \(\vec \nu_{nw}\) the fluid-fluid interface conormal [Duriez2017c], and \(\vec x\) the position. (auto-updated)

  property muSnw

    Tensorial contribution to sigmaCap from the wetting/non-wetting (e.g. liquid/gas) interface \(S{nw}\): \(\boldsymbol{\mu_{Snw}} = \int_{Snw} (\boldsymbol \delta - \vec n \otimes \vec n) dS\) with \(\vec n\) the outward normal and \(\boldsymbol{\delta}\) the identity tensor. (auto-updated)

  property muSsw

    Tensorial contribution to sigmaCap from the wetted solid surfaces \(Ssw\): \(\boldsymbol{\mu_{Ssw}} = \int_{Ssw} \vec n \otimes \vec x dS\) with \(\vec n\) the outward normal and \(\vec x\) the position. (auto-updated)

  property muVw

    Tensorial contribution (spherical i.e. isotropic) to sigmaCap from the wetting fluid volume: \(\boldsymbol{\mu_{Vw}} = V_w \, \boldsymbol{\delta}\) with \(V_w =\) vW and \(\boldsymbol{\delta}\) the identity tensor. (auto-updated)

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property sigmaCap

    The capillary stress tensor \(\boldsymbol{\sigma^{cap}}\) itself, expressed as \(\boldsymbol{\sigma^{cap}} = 1/V \, [ u_c (\boldsymbol{\mu_{Vw}} + \boldsymbol{\mu_{Ssw}}) + \gamma_{nw} (\boldsymbol{\mu_{Snw}} + \boldsymbol{\mu_{\Gamma}}) ]\) where the four microstructure tensors \(\boldsymbol{\mu_{Vw}}, \boldsymbol{\mu_{Ssw}}, \boldsymbol{\mu_{Snw}}, \boldsymbol{\mu_{\Gamma}}\) correspond to muVw, muSsw, muSnw and muGamma attributes. (auto-updated)

  property surfaceTension

    Fluid-fluid surface tension \(\gamma_{nw}\), to be defined equal to Law2_ScGeom_CapillaryPhys_Capillarity.surfaceTension.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vW

    Wetting fluid volume, summing menisci volumes (faster here than through python loops). (auto-updated)

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

  property wettAngle

    Wetting, i.e. contact, angle value (radians). To be defined consistently with the value upon which the capillary files (used by Law2_ScGeom_CapillaryPhys_Capillarity) rely.

class yade.wrapper.PDFEngine(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Base class for spectrums calculations. Compute Probability Density Functions of normalStress, shearStress, distance, velocity and interactions in spherical coordinates and write result to a file. Column name format is: Data(theta, phi). Convention used: x: phi = 0, y: theta = 0, z: phi = pi/2

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property filename

    Filename

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property numDiscretizeAnglePhi

    Number of sector for phi-angle

  property numDiscretizeAngleTheta

    Number of sector for theta-angle

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

  property warnedOnce

    For one-time warning. May trigger usefull warnings

class yade.wrapper.PotentialParticleVTKRecorder(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Engine recording potential blocks as surfaces into files with given periodicity.

  property REC_COLORS

    Whether to record colors

  property REC_ID

    Whether to record id

  property REC_INTERACTION

    Whether to record contact point and forces

  property REC_VELOCITY

    Whether to record velocity

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property fileName

    File prefix to save to

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxDimension

    Maximum allowed distance between consecutive grid lines

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property sampleX

    Number of divisions in the X direction for triangulation

  property sampleY

    Number of divisions in the Y direction for triangulation

  property sampleZ

    Number of divisions in the Z direction for triangulation

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property twoDimension

    Whether to render the particles as 2-D

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.PyRunner(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Execute a python command periodically, with defined (and adjustable) periodicity. See PeriodicEngine documentation for details.

  property command

    Command to be run by python interpreter. Not run if empty.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property ignoreErrors

    Debug only: set this value to true to tell PyRunner to ignore any errors encountered during command execution.

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updateGlobals

    Whether to workaround ipython not recognizing local variables by calling `globals().update(locals())`. If `true` then PyRunner is able to call functions declared later locally in a running live yade session. The `PyRunner` call is a bit slower because it updates `globals()` with recently declared python functions.

    Warning

    > When `updateGlobals==False` and a function was declared inside a live yade session (ipython) then an error `NameError: name 'command' is not defined` will occur unless python `globals()` are updated with command

    >     globals().update(locals())

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.Recorder(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Engine periodically storing some data to (one) external file. In addition PeriodicEngine, it handles opening the file as needed. See PeriodicEngine for controlling periodicity.

  property addIterNum

    Adds an iteration number to the file name, when the file was created. Useful for creating new files at each call (false by default)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property file

    Name of file to save to; must not be empty.

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property truncate

    Whether to delete current file contents, if any, when opening (false by default)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.ResetRandomPosition(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Creates spheres during simulation, placing them at random positions. Every time called, one new sphere will be created and inserted in the simulation.

  property angularVelocity

    Mean angularVelocity of spheres.

  property angularVelocityRange

    Half size of a angularVelocity distribution interval. New sphere will have random angularVelocity within the range angularVelocity±angularVelocityRange.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property factoryFacets

    The geometry of the section where spheres will be placed; they will be placed on facets or in volume between them depending on volumeSection flag.

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxAttempts

    Max attempts to place sphere. If placing the sphere in certain random position would cause an overlap with any other physical body in the model, SpheresFactory will try to find another position.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property normal

    ??

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property point

    ??

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property subscribedBodies

    Affected bodies.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property velocity

    Mean velocity of spheres.

  property velocityRange

    Half size of a velocities distribution interval. New sphere will have random velocity within the range velocity±velocityRange.

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

  property volumeSection

    Create new spheres inside factory volume rather than on its surface.

class yade.wrapper.SegmentedMatSprinkler(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  A periodic engine distributing coating material of particles having CohFrictMatSeg. Determines the particles to cover by ray tracing algorithm.

  property alpha

    Angle (degrees) defining width of the stream in the first direction.

  property alphaResolution

    How many searching lines scan one cross-section in first direction

  property beta

    Angle (degrees) defining width of the stream in the second direction.

  property betaResolution

    How many searching lines scan one cross-section in first direction

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property feedRate

    Volume of the material distributed per second (unit is \(1000^3\) smaller than volume unit of the simulation, see SegmentedState.coatingThickness for explanation).

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property lostVolume

    Released volume that did not reach any target.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property pos

    Origin of the sprinkling source.

  property prevTime

    Virtual time of the last run. Compared to the PeriodicEngine::virtLast, it is updated after the action of the engine.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property refDir

    Reference direction of SegmentedMatSprinkler (center of the stream). It should not be directly modified. When the direction of sprinkler is rotated in setVersors function, this direction is taken as reference.

  property releasedVolume

    Volume released by the sprinkler since the begining of its work.

  setVersors((SegmentedMatSprinkler)arg1, (yade._minieigenHP.Quaternion)arg2) → None :

    Sets versors of lines searching for the surfaces of closest spheres. Should always be used after changing any parameters of SegmentedMatSprinkler other than feedRate.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property versors

    Versors of the searching lines.

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.SegmentedStateUpdater(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  This class provides methods for setting the coating thickness of bodies and performing the coating material transfer (both interparticle and intraparticle).

  property activateWettability

    If true, particles are wettable (coating material is distributed over particles with time). It works only for spherical particles. For clumps of spheres it is recommended to set false.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  initialize((SegmentedStateUpdater)arg1, (int)arg2, (float)arg3) → None :

    Initializes SegmentedState::coatingThickness, so it has a proper length and next, sets the same thickness to all the segments. Not initialized bodies cannot exchange the coating material.

  property interParticleExchangeCoeff

    Rate of coating material exchange rate coefficient between two contacting particles.

  property intraParticleExchangeCoeff

    Rate of coating material exchange rate coefficient between two segments of the same particle.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property phiResolution

    In how many regions a coating map of sphere should be divided horizontally (phi is azimuthal angle ranging from 0 to 360 degrees).

  property prevTime

    Virtual time of the last run. Compared to the PeriodicEngine::virtLast, it is updated after the action of the engine.

  property reInitCohesion

    This parameter is introduced to reinitialize the cohesion after two bodies exchange the coating material. That means it sets CohFrictPhys::initCohesion true for the interaction. It is later determined by Ip2, whether the interaction should be cohesive (based on the material properties). Default value is 1 which means that reinitialization works only for interactions that are not yet cohesive (CohFrictPhys::cohesionBroken is true). Set 2, in order to reinitialize cohesion on every run of SegmentedStateUpdater.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  setThicknessToFacetSide((SegmentedStateUpdater)arg1, (int)arg2, (int)arg3, (float)arg4) → None :

    Set thickness to facet side (0 to negative side, 1 to positive side, according to facet normal).

  setThicknessToSphereSeg((SegmentedStateUpdater)arg1, (int)arg2, (int)arg3, (int)arg4, (float)arg5) → None :

    Set thickness to the segment of sphere at position given by phi and theta.

  setThicknessToSpheres((SegmentedStateUpdater)arg1, (object)arg2, (int)arg3, (int)arg4, (int)arg5, (int)arg6, (float)arg7) → None :

    For each sphere from provided list (of Ids) set thickness at some range of segments specified by minimum and maximum theta and phi.

  property thetaResolution

    In how many regions a coating map of sphere should be divided vertically (theta is polar angle ranging from 0 to 180 degrees).

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.SnapshotEngine(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Periodically save snapshots of GLView(s) as .png files. Files are named fileBase + counter + ‘.png’ (counter is left-padded by 0s, i.e. snap00004.png).

  property counter

    Number that will be appended to fileBase when the next snapshot is saved (incremented at every save). (auto-updated)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  property deadTimeout

    Timeout for 3d operations (opening new view, saving snapshot); after timing out, throw exception (or only report error if ignoreErrors) and make myself dead. [s]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property fileBase

    Basename for snapshots

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property format

    Format of snapshots (one of JPEG, PNG, EPS, PS, PPM, BMP) QGLViewer documentation. File extension will be lowercased format. Validity of format is not checked.

  property ignoreErrors

    Only report errors instead of throwing exceptions, in case of timeouts.

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property msecSleep

    number of msec to sleep after snapshot (to prevent 3d hw problems) [ms]

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property plot

    Name of field in plot.imgData to which taken snapshots will be appended automatically.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property snapshots

    Files that have been created so far

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.TorqueRecorder(inherits Recorder → PeriodicEngine → GlobalEngine → Engine → Serializable)

  Engine saves the total torque according to the given axis and ZeroPoint, the force is taken from bodies, listed in ids For instance, can be useful for defining the torque, which affects on ball mill during its work.

  property addIterNum

    Adds an iteration number to the file name, when the file was created. Useful for creating new files at each call (false by default)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property file

    Name of file to save to; must not be empty.

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property ids

    List of bodies whose state will be measured

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property rotationAxis

    Rotation axis

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property totalTorque

    Resultant torque, returning by the function.

  property truncate

    Whether to delete current file contents, if any, when opening (false by default)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

  property zeroPoint

    Point of rotation center

class yade.wrapper.TriaxialStateRecorder(inherits Recorder → PeriodicEngine → GlobalEngine → Engine → Serializable)

  Engine recording triaxial variables (see the variables list in the first line of the output file). This recorder needs TriaxialCompressionEngine or ThreeDTriaxialEngine present in the simulation).

  property addIterNum

    Adds an iteration number to the file name, when the file was created. Useful for creating new files at each call (false by default)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property file

    Name of file to save to; must not be empty.

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property porosity

    porosity of the packing [-]

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property truncate

    Whether to delete current file contents, if any, when opening (false by default)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

class yade.wrapper.VTKRecorder(inherits PeriodicEngine → GlobalEngine → Engine → Serializable)

  Engine recording snapshots of simulation into series of *.vtu files, readable by VTK-based postprocessing programs such as Paraview. Both bodies (depending on their shapes) and interactions can be recorded, with various vector/scalar quantities that are defined on them.

  PeriodicEngine.initRun is initialized to `True` automatically.

  property Key

    Necessary if recorders contains ‘cracks’ or ‘moments’. A string specifying the name of file ‘cracks___.txt’ that is considered in this case (see corresponding attribute).

  property ascii

    Store data as readable text in the XML file (sets vtkXMLWriter data mode to `vtkXMLWriter::Ascii`, while the default is `Appended`)

  property compress

    Compress output XML files [experimental].

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property fileName

    Base file name; it will be appended with {lsBody*,spheres,intrs,facets}.243100.vtu (unless multiblock or multiblockLS is `True`) depending on active recorders and step number (243100 in this case). It can contain slashes, but the directory must exist already.

  property firstIterRun

    Sets the step number, at each an engine should be executed for the first time (disabled by default).

  property initRun

    Run the first time we are called as well.

  property iterLast

    Tracks step number of last run (auto-updated).

  property iterPeriod

    Periodicity criterion using step number (deactivated if <= 0)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mask

    If mask defined, only bodies with corresponding groupMask will be exported. If 0, all bodies will be exported.

  property multiblock

    Use multi-block (`.vtm`) files to store data, rather than separate `.vtu` files.

  property multiblockLS

    For executing, when True and with lsBodies in recorders, a serial export of the LevelSet bodies into one unique multi-block (`.vtm`) file, rather than a OpenMP export of separate `.vts` files, when False. Compatibility with multiblock has not been implemented yet

  property nDo

    Limit number of executions by this number (deactivated if negative)

  property nDone

    Track number of executions (cummulative) (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property parallelMode

    For MPI parallel runs, each proc writes their own vtu/vtp files. Master proc writes a pvtu/pvtp file containing metadata about worker vtu files. load the pvtu/pvtp in paraview for visualization.

  property realLast

    Tracks real time of last run (auto-updated).

  property realPeriod

    Periodicity criterion using real (wall clock, computation, human) time in seconds (deactivated if <=0)

  property recorders

    List of active recorders (as strings). `all` (the default value) enables all base (``lsBodies’’ excepted) and generic recorders.

    Base recorders

    > Base recorders save the geometry (unstructured or structured grids) on which other data is defined. They are implicitly activated by many of the other recorders. Each of them creates a new file (or a block, if multiblock is set).

    > `spheres`

    >   Saves positions and radii (`radii`) of spherical particles.

    > `facets`

    >   Save facets positions (vertices).

    > `boxes`

    >   Save boxes positions (edges).

    > `lsBodies`

    >   Exports LevelSet shaped bodies in global frame, after mapping to current positions and orientations their grid with distance fields. A Python function (to use within Paraview) is provided at examples/levelSet/pvVisu.py for helping bodies’ surfaces rendering in Paraview.

    > `intr`

    >   Store interactions as lines between nodes at respective particles positions. Additionally stores on interactions (the geom) the signed magnitude of normal force (`forceN`) and the component-wise absolute value of shear force (`absForceT`).

    Generic recorders

    > Generic recorders do not depend on specific model being used and save commonly useful data.

    > `id`

    >   Saves id’s (field `id`) of spheres; active only if `spheres` is active.

    > `mass`

    >   Saves masses (field `mass`) of spheres; active only if `spheres` is active.

    > `clumpId`

    >   Saves id’s of clumps to which each sphere belongs (field `clumpId`); active only if `spheres` is active.

    > `colors`

    >   Saves colors of spheres and of facets (field `color`); only active if `spheres` or `facets` are activated.

    > `mask`

    >   Saves groupMasks of spheres and of facets (field `mask`); only active if `spheres` or `facets` are activated.

    > `materialId`

    >   Saves materialID of spheres and of facets; only active if `spheres` or `facets` are activated.

    > `coordNumber`

    >   Saves coordination number (number of neighbours) of spheres and of facets; only active if `spheres` or `facets` are activated.

    > `velocity`

    >   Saves linear and angular velocities of spherical particles as Vector3 and length(fields `linVelVec`, `linVelLen` and `angVelVec`, `angVelLen` respectively``); only effective with `spheres`.

    > `force`

    >   Saves force and torque of spheres, facets and boxes as Vector3 and length (norm); only active if `spheres`, `facets` or `boxes` are activated.

    > `pericell`

    >   Saves the shape of the cell (simulation has to be periodic).

    > `bstresses`

    >   For spheres (if activated) and while considering the per-particle stress tensors as given by bodyStressTensors, saves the per-particle principal stresses, sigI (most tensile) \(\geq\) sigII \(\geq\) sigIII (most compressive), and the associated principal directions dirI, dirII, dirIII.

    Specific recorders

    > > The following should only be activated in when appropriate engines/contact laws are in use, otherwise crashes can occur due to violation of type presuppositions.

    > > `cpm`

    > >   Saves data pertaining to the concrete model: `cpmDamage` (normalized residual strength averaged on particle), `cpmStress` (stress on particle); `intr` is activated automatically by `cpm`

    > > `wpm`

    > >   Saves data pertaining to the wire particle model: `wpmForceNFactor` shows the loading factor for the wire, e.g. normal force divided by threshold normal force.

    > > `jcfpm`

    > >   Saves data pertaining to the rock (smooth)-jointed model: `damage` is defined by JCFpmState.tensBreak + JCFpmState.shearBreak; `intr` is activated automatically by `jcfpm`, and on joint or cohesive interactions can be vizualized.

    > > `cracks`

    > >   Saves other data pertaining to the rock model: `cracks` shows locations where cohesive bonds failed during the simulation, with their types (0/1 for tensile/shear breakages), their sizes (0.5*(R1+R2)), and their normal directions. The corresponding attribute has to be activated, and Key attributes have to be consistent.

    > > `moments`

    > >   Saves data pertaining to the required corresponding attribute:yref:acoustic emissions model<Law2_ScGeom_JCFpmPhys_JointedCohesiveFrictionalPM.recordMoments>: `moments` shows locations of acoustic emissions, the number of broken bonds comprising the acoustic emission, the magnitude.

    > > `thermal`

    > >   Saves temperature of bodies computed using Yade’s ThermalEngine.

    > > `liquid`

    > >   Saves the liquid volume associated with capillary models.

    > > `cohfrict`

    > >   Saves interaction information associated with the cohesive frictional model, including isBroken, unp, and breakType.

    > > `SPH`

    > >   Saves sphere information associated with Yade’s SPH module.

    > > `deform`

    > >   Saves interaction information associated with Yade’s deformation module.

    > > `lubrication`

    > >   Saves lubrications stress from LubricationPhys. `spheres` must be active.

    > > `partialsat`

    > >   Saves suction and radii changes of spheres associated with PartialSatClayEngine. `spheres` must be active.

    > > `hertz`

    > >   Saves bond data from hertzmindlin such as displacement or ‘broken’ where broken follows a displacement criteria set by user in Law2_ScGeom_MindlinPhys_Mindlin.

  property skipFacetIntr

    Skip interactions that are not of sphere-sphere type (e.g. sphere-facet, sphere-box…), when saving interactions

  property skipNondynamic

    Skip non-dynamic spheres (but not facets).

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property virtLast

    Tracks virtual time of last run (auto-updated).

  property virtPeriod

    Periodicity criterion using virtual (simulation) time (deactivated if <= 0)

### BoundaryController

Inheritance graph of BoundaryController.

class yade.wrapper.BoundaryController(inherits GlobalEngine → Engine → Serializable)

  Base for engines controlling boundary conditions of simulations. Not to be used directly.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Disp2DPropLoadEngine(inherits BoundaryController → GlobalEngine → Engine → Serializable)

  Disturbs a simple shear sample in a given displacement direction

  This engine allows one to apply, on a simple shear sample, a loading controlled by du/dgamma = cste, which is equivalent to du + cste’ * dgamma = 0 (proportionnal path loadings). To do so, the upper plate of the simple shear box is moved in a given direction (corresponding to a given du/dgamma), whereas lateral plates are moved so that the box remains closed. This engine can easily be used to perform directionnal probes, with a python script launching successivly the same .xml which contains this engine, after having modified the direction of loading (see theta attribute). That’s why this Engine contains a saveData procedure which can save data on the state of the sample at the end of the loading (in case of successive loadings - for successive directions - through a python script, each line would correspond to one direction of loading).

  property Key

    string to add at the names of the saved files, and of the output file filled by saveData

  property LOG

    boolean controling the output of messages on the screen

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property id_boxback

    the id of the wall at the back of the sample

  property id_boxbas

    the id of the lower wall

  property id_boxfront

    the id of the wall in front of the sample

  property id_boxleft

    the id of the left wall

  property id_boxright

    the id of the right wall

  property id_topbox

    the id of the upper wall

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nbre_iter

    the number of iterations of loading to perform

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property theta

    the angle, in a (gamma,h=-u) plane from the gamma - axis to the perturbation vector (trigo wise) [degrees]

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property v

    the speed at which the perturbation is imposed. In case of samples which are more sensitive to normal loadings than tangential ones, one possibility is to take v = V_shear - | (V_shear-V_comp)*sin(theta) | => v=V_shear in shear; V_comp in compression [m/s]

class yade.wrapper.KinemCNDEngine(inherits KinemSimpleShearBox → BoundaryController → GlobalEngine → Engine → Serializable)

  To apply a Constant Normal Displacement (CND) shear for a parallelogram box

  This engine, designed for simulations implying a simple shear box (SimpleShear Preprocessor or scripts/simpleShear.py), allows one to perform a constant normal displacement shear, by translating horizontally the upper plate, while the lateral ones rotate so that they always keep contact with the lower and upper walls.

  property Key

    string to add at the names of the saved files

  property LOG

    boolean controling the output of messages on the screen

  property alpha

    the angle from the lower box to the left box (trigo wise). Measured by this Engine. Has to be saved, but not to be changed by the user.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property f0

    the (vertical) force acting on the upper plate on the very first time step (determined by the Engine). Controls of the loadings in case of KinemCNSEngine or KinemCNLEngine will be done according to this initial value [\(N\)]. Has to be saved, but not to be changed by the user.

  property firstRun

    boolean set to false as soon as the engine has done its job one time : useful to know if initial height of, and normal force sustained by, the upper box are known or not (and thus if they have to be initialized). Has to be saved, but not to be changed by the user.

  property gamma

    the current value of the tangential displacement

  property gamma_save

    vector with the values of gamma at which a save of the simulation is performed [m]

  property gammalim

    the value of the tangential displacement at wich the displacement is stopped [m]

  property id_boxback

    the id of the wall at the back of the sample

  property id_boxbas

    the id of the lower wall

  property id_boxfront

    the id of the wall in front of the sample

  property id_boxleft

    the id of the left wall

  property id_boxright

    the id of the right wall

  property id_topbox

    the id of the upper wall

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property max_vel

    to limit the speed of the vertical displacements done to control \(\sigma\) (CNL or CNS cases) [\(m/s\)]

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property shearSpeed

    the speed at which the shear is performed : speed of the upper plate [m/s]

  property temoin_save

    vector (same length as ‘gamma_save’ for ex), with 0 or 1 depending whether the save for the corresponding value of gamma has been done (1) or not (0). Has to be saved, but not to be changed by the user.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wallDamping

    the vertical displacements done to to control \(\sigma\) (CNL or CNS cases) are in fact damped, through this wallDamping

  property y0

    the height of the upper plate at the very first time step : the engine finds its value [\(m\)]. Has to be saved, but not to be changed by the user.

class yade.wrapper.KinemCNLEngine(inherits KinemSimpleShearBox → BoundaryController → GlobalEngine → Engine → Serializable)

  To apply a constant normal stress shear (i.e. Constant Normal Load : CNL) for a parallelogram box (simple shear box : SimpleShear Preprocessor or scripts/simpleShear.py)

  This engine allows one to translate horizontally the upper plate while the lateral ones rotate so that they always keep contact with the lower and upper walls.

  In fact the upper plate can move not only horizontally but also vertically, so that the normal stress acting on it remains constant (this constant value is not chosen by the user but is the one that exists at the beginning of the simulation)

  The right vertical displacements which will be allowed are computed from the rigidity Kn of the sample over the wall (so to cancel a deltaSigma, a normal dplt deltaSigma*S/(Kn) is set)

  The movement is moreover controlled by the user via a shearSpeed which will be the speed of the upper wall, and by a maximum value of horizontal displacement gammalim, after which the shear stops.

  Note

  Not only the positions of walls are updated but also their speeds, which is all but useless considering the fact that in the contact laws these velocities of bodies are used to compute values of tangential relative displacements.

  Warning

  Because of this last point, if you want to use later saves of simulations executed with this Engine, but without that stopMovement was executed, your boxes will keep their speeds => you will have to cancel them ‘by hand’ in the .xml.

  property Key

    string to add at the names of the saved files

  property LOG

    boolean controling the output of messages on the screen

  property alpha

    the angle from the lower box to the left box (trigo wise). Measured by this Engine. Has to be saved, but not to be changed by the user.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property f0

    the (vertical) force acting on the upper plate on the very first time step (determined by the Engine). Controls of the loadings in case of KinemCNSEngine or KinemCNLEngine will be done according to this initial value [\(N\)]. Has to be saved, but not to be changed by the user.

  property firstRun

    boolean set to false as soon as the engine has done its job one time : useful to know if initial height of, and normal force sustained by, the upper box are known or not (and thus if they have to be initialized). Has to be saved, but not to be changed by the user.

  property gamma

    current value of tangential displacement [m]

  property gamma_save

    vector with the values of gamma at which a save of the simulation is performed [m]

  property gammalim

    the value of tangential displacement (of upper plate) at wich the shearing is stopped [m]

  property id_boxback

    the id of the wall at the back of the sample

  property id_boxbas

    the id of the lower wall

  property id_boxfront

    the id of the wall in front of the sample

  property id_boxleft

    the id of the left wall

  property id_boxright

    the id of the right wall

  property id_topbox

    the id of the upper wall

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property max_vel

    to limit the speed of the vertical displacements done to control \(\sigma\) (CNL or CNS cases) [\(m/s\)]

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property shearSpeed

    the speed at wich the shearing is performed : speed of the upper plate [m/s]

  property temoin_save

    vector (same length as ‘gamma_save’ for ex), with 0 or 1 depending whether the save for the corresponding value of gamma has been done (1) or not (0). Has to be saved, but not to be changed by the user.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wallDamping

    the vertical displacements done to to control \(\sigma\) (CNL or CNS cases) are in fact damped, through this wallDamping

  property y0

    the height of the upper plate at the very first time step : the engine finds its value [\(m\)]. Has to be saved, but not to be changed by the user.

class yade.wrapper.KinemCNSEngine(inherits KinemSimpleShearBox → BoundaryController → GlobalEngine → Engine → Serializable)

  To apply a Constant Normal Stifness (CNS) shear for a parallelogram box (simple shear)

  This engine, useable in simulations implying one deformable parallelepipedic box, allows one to translate horizontally the upper plate while the lateral ones rotate so that they always keep contact with the lower and upper walls. The upper plate can move not only horizontally but also vertically, so that the normal rigidity defined by DeltaF(upper plate)/DeltaU(upper plate) = constant (= KnC defined by the user).

  The movement is moreover controlled by the user via a shearSpeed which is the horizontal speed of the upper wall, and by a maximum value of horizontal displacement gammalim (of the upper plate), after which the shear stops.

  Note

  not only the positions of walls are updated but also their speeds, which is all but useless considering the fact that in the contact laws these velocities of bodies are used to compute values of tangential relative displacements.

  Warning

  But, because of this last point, if you want to use later saves of simulations executed with this Engine, but without that stopMovement was executed, your boxes will keep their speeds => you will have to cancel them by hand in the .xml

  property Key

    string to add at the names of the saved files

  property KnC

    the normal rigidity chosen by the user [MPa/mm] - the conversion in Pa/m will be made

  property LOG

    boolean controling the output of messages on the screen

  property alpha

    the angle from the lower box to the left box (trigo wise). Measured by this Engine. Has to be saved, but not to be changed by the user.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property f0

    the (vertical) force acting on the upper plate on the very first time step (determined by the Engine). Controls of the loadings in case of KinemCNSEngine or KinemCNLEngine will be done according to this initial value [\(N\)]. Has to be saved, but not to be changed by the user.

  property firstRun

    boolean set to false as soon as the engine has done its job one time : useful to know if initial height of, and normal force sustained by, the upper box are known or not (and thus if they have to be initialized). Has to be saved, but not to be changed by the user.

  property gamma

    current value of tangential displacement [m]

  property gammalim

    the value of tangential displacement (of upper plate) at wich the shearing is stopped [m]

  property id_boxback

    the id of the wall at the back of the sample

  property id_boxbas

    the id of the lower wall

  property id_boxfront

    the id of the wall in front of the sample

  property id_boxleft

    the id of the left wall

  property id_boxright

    the id of the right wall

  property id_topbox

    the id of the upper wall

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property max_vel

    to limit the speed of the vertical displacements done to control \(\sigma\) (CNL or CNS cases) [\(m/s\)]

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property shearSpeed

    the speed at wich the shearing is performed : speed of the upper plate [m/s]

  property temoin_save

    vector (same length as ‘gamma_save’ for ex), with 0 or 1 depending whether the save for the corresponding value of gamma has been done (1) or not (0). Has to be saved, but not to be changed by the user.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wallDamping

    the vertical displacements done to to control \(\sigma\) (CNL or CNS cases) are in fact damped, through this wallDamping

  property y0

    the height of the upper plate at the very first time step : the engine finds its value [\(m\)]. Has to be saved, but not to be changed by the user.

class yade.wrapper.KinemCTDEngine(inherits KinemSimpleShearBox → BoundaryController → GlobalEngine → Engine → Serializable)

  To compress a simple shear sample by moving the upper box in a vertical way only, so that the tangential displacement (defined by the horizontal gap between the upper and lower boxes) remains constant (thus, the CTD = Constant Tangential Displacement). The lateral boxes move also to keep always contact. All that until this box is submitted to a given stress (targetSigma). Moreover saves are executed at each value of stresses stored in the vector sigma_save, and at targetSigma

  property Key

    string to add at the names of the saved files

  property LOG

    boolean controling the output of messages on the screen

  property alpha

    the angle from the lower box to the left box (trigo wise). Measured by this Engine. Has to be saved, but not to be changed by the user.

  property compSpeed

    (vertical) speed of the upper box : >0 for real compression, <0 for unloading [\(m/s\)]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property f0

    the (vertical) force acting on the upper plate on the very first time step (determined by the Engine). Controls of the loadings in case of KinemCNSEngine or KinemCNLEngine will be done according to this initial value [\(N\)]. Has to be saved, but not to be changed by the user.

  property firstRun

    boolean set to false as soon as the engine has done its job one time : useful to know if initial height of, and normal force sustained by, the upper box are known or not (and thus if they have to be initialized). Has to be saved, but not to be changed by the user.

  property id_boxback

    the id of the wall at the back of the sample

  property id_boxbas

    the id of the lower wall

  property id_boxfront

    the id of the wall in front of the sample

  property id_boxleft

    the id of the left wall

  property id_boxright

    the id of the right wall

  property id_topbox

    the id of the upper wall

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property max_vel

    to limit the speed of the vertical displacements done to control \(\sigma\) (CNL or CNS cases) [\(m/s\)]

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property sigma_save

    vector with the values of sigma at which a save of the simulation should be performed [\(kPa\)]

  property targetSigma

    the value of sigma at which the compression should stop [\(kPa\)]

  property temoin_save

    vector (same length as ‘gamma_save’ for ex), with 0 or 1 depending whether the save for the corresponding value of gamma has been done (1) or not (0). Has to be saved, but not to be changed by the user.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wallDamping

    the vertical displacements done to to control \(\sigma\) (CNL or CNS cases) are in fact damped, through this wallDamping

  property y0

    the height of the upper plate at the very first time step : the engine finds its value [\(m\)]. Has to be saved, but not to be changed by the user.

class yade.wrapper.KinemSimpleShearBox(inherits BoundaryController → GlobalEngine → Engine → Serializable)

  This class is supposed to be a mother class for all Engines performing loadings on the simple shear box of SimpleShear. It is not intended to be used by itself, but its declaration and implentation will thus contain all what is useful for all these Engines. The script simpleShear.py illustrates the use of the various corresponding Engines.

  property Key

    string to add at the names of the saved files

  property LOG

    boolean controling the output of messages on the screen

  property alpha

    the angle from the lower box to the left box (trigo wise). Measured by this Engine. Has to be saved, but not to be changed by the user.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property f0

    the (vertical) force acting on the upper plate on the very first time step (determined by the Engine). Controls of the loadings in case of KinemCNSEngine or KinemCNLEngine will be done according to this initial value [\(N\)]. Has to be saved, but not to be changed by the user.

  property firstRun

    boolean set to false as soon as the engine has done its job one time : useful to know if initial height of, and normal force sustained by, the upper box are known or not (and thus if they have to be initialized). Has to be saved, but not to be changed by the user.

  property id_boxback

    the id of the wall at the back of the sample

  property id_boxbas

    the id of the lower wall

  property id_boxfront

    the id of the wall in front of the sample

  property id_boxleft

    the id of the left wall

  property id_boxright

    the id of the right wall

  property id_topbox

    the id of the upper wall

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property max_vel

    to limit the speed of the vertical displacements done to control \(\sigma\) (CNL or CNS cases) [\(m/s\)]

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property temoin_save

    vector (same length as ‘gamma_save’ for ex), with 0 or 1 depending whether the save for the corresponding value of gamma has been done (1) or not (0). Has to be saved, but not to be changed by the user.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wallDamping

    the vertical displacements done to to control \(\sigma\) (CNL or CNS cases) are in fact damped, through this wallDamping

  property y0

    the height of the upper plate at the very first time step : the engine finds its value [\(m\)]. Has to be saved, but not to be changed by the user.

class yade.wrapper.Peri3dController(inherits BoundaryController → GlobalEngine → Engine → Serializable)

  Class for controlling independently all 6 components of “engineering” stress and strain of periodic Cell. goal are the goal values, while stressMask determines which components prescribe stress and which prescribe strain.

  If the strain is prescribed, appropriate strain rate is directly applied. If the stress is prescribed, the strain predictor is used: from stress values in two previous steps the value of strain rate is prescribed so as the value of stress in the next step is as close as possible to the ideal one. Current algorithm is extremly simple and probably will be changed in future, but is roboust enough and mostly works fine.

  Stress error (difference between actual and ideal stress) is evaluated in current and previous steps (\(\mathrm{d}\sigma_i,\mathrm{d}\sigma_{i-1}\)). Linear extrapolation is used to estimate error in the next step

  \[\mathrm{d}\sigma_{i+1}=2\mathrm{d}\sigma_i - \mathrm{d}\sigma_{i-1}\]

  According to this error, the strain rate is modified by mod parameter

  \[\begin{split}\mathrm{d}\sigma_{i+1}\left\{\begin{array}{c} >0 \rightarrow \dot{\varepsilon}_{i+1} = \dot{\varepsilon}_i - \max(\mathrm{abs}(\dot{\boldsymbol{\varepsilon}}_i))\cdot\mathrm{mod} \\ <0 \rightarrow \dot{\varepsilon}_{i+1} = \dot{\varepsilon}_i + \max(\mathrm{abs}(\dot{\boldsymbol{\varepsilon}}_i))\cdot\mathrm{mod} \end{array}\right.\end{split}\]

  According to this fact, the prescribed stress will (almost) never have exact prescribed value, but the difference would be very small (and decreasing for increasing nSteps. This approach works good if one of the dominant strain rates is prescribed. If all stresses are prescribed or if all goal strains is prescribed as zero, a good estimation is needed for the first step, therefore the compliance matrix is estimated (from user defined estimations of macroscopic material parameters youngEstimation and poissonEstimation) and respective strain rates is computed form prescribed stress rates and compliance matrix (the estimation of compliance matrix could be computed autamatically avoiding user inputs of this kind).

  The simulation on rotated periodic cell is also supported. Firstly, the polar decomposition is performed on cell’s transformation matrix trsf \(\mathcal{T}=\mat{U}\mat{P}\), where \(\mat{U}\) is orthogonal (unitary) matrix representing rotation and \(\mat{P}\) is a positive semi-definite Hermitian matrix representing strain. A logarithm of \(\mat{P}\) should be used to obtain realistic values at higher strain values (not implemented yet). A prescribed strain increment in global coordinates \(\mathrm{d}t\cdot\dot{\boldsymbol{\varepsilon}}\) is properly rotated to cell’s local coordinates and added to \(\mat{P}\)

  \[\mat{P}_{i+1}=\mat{P}+\mat{U}^{\mathsf{T}}\mathrm{d}t\cdot\dot{\boldsymbol{\varepsilon}}\mat{U}\]

  The new value of trsf is computed at \(\mat{T}_{i+1}=\mat{UP}_{i+1}\). From current and next trsf the cell’s velocity gradient velGrad is computed (according to its definition) as

  \[\mat{V} = (\mat{T}_{i+1}\mat{T}^{-1}-\mat{I})/\mathrm{d}t\]

  Current implementation allow user to define independent loading “path” for each prescribed component. i.e. define the prescribed value as a function of time (or progress or steps). See Paths.

  Examples examples/test/peri3dController_example1.py and examples/test/peri3dController_triaxialCompression.py explain usage and inputs of Peri3dController, examples/test/peri3dController_shear.py is an example of using shear components and also simulation on rotated cell.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property doneHook

    Python command (as string) to run when nSteps is achieved. If empty, the engine will be set dead.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property goal

    Goal state; only the upper triangular matrix is considered; each component is either prescribed stress or strain, depending on stressMask.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property lenPe

    Peri3dController internal variable

  property lenPs

    Peri3dController internal variable

  property maxStrain

    Maximal asolute value of strain allowed in the simulation. If reached, the simulation is considered as finished

  property maxStrainRate

    Maximal absolute value of strain rate (both normal and shear components of strain)

  property mod

    Predictor modificator, by trail-and-error analysis the value 0.1 was found as the best.

  property nSteps

    Number of steps of the simulation.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property pathSizes

    Peri3dController internal variable

  property pathsCounter

    Peri3dController internal variable

  property pe

    Peri3dController internal variable

  property poissonEstimation

    Estimation of macroscopic Poisson’s ratio, used used for the first simulation step

  property progress

    Actual progress of the simulation with Controller.

  property ps

    Peri3dController internal variable

  property strain

    Current strain (deformation) vector (\(\varepsilon_x\),\(\varepsilon_y\),\(\varepsilon_z\),\(\gamma_{yz}\),\(\gamma_{zx}\),\(\gamma_{xy}\)) (auto-updated).

  property strainGoal

    Peri3dController internal variable

  property strainRate

    Current strain rate vector.

  property stress

    Current stress vector (\(\sigma_x\),\(\sigma_y\),\(\sigma_z\),\(\tau_{yz}\),\(\tau_{zx}\),\(\tau_{xy}\))|yupdate|.

  property stressGoal

    Peri3dController internal variable

  property stressIdeal

    Ideal stress vector at current time step.

  property stressMask

    mask determining whether components of goal are strain (0) or stress (1). The order is 00,11,22,12,02,01 from the least significant bit. (e.g. 0b000011 is stress 00 and stress 11).

  property stressRate

    Current stress rate vector (that is prescribed, the actual one slightly differ).

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property xxPath

    “Time function” (piecewise linear) for xx direction. Sequence of couples of numbers. First number is time, second number desired value of respective quantity (stress or strain). The last couple is considered as final state (equal to (nSteps, goal)), other values are relative to this state.

    Example: nSteps=1000, goal[0]=300, xxPath=((2,3),(4,1),(5,2))

    at step 400 (=5*1000/2) the value is 450 (=3*300/2),

    at step 800 (=4*1000/5) the value is 150 (=1*300/2),

    at step 1000 (=5*1000/5=nSteps) the value is 300 (=2*300/2=goal[0]).

    See example scripts/test/peri3dController_example1 for illusration.

  property xyPath

    Time function for xy direction, see xxPath

  property youngEstimation

    Estimation of macroscopic Young’s modulus, used for the first simulation step

  property yyPath

    Time function for yy direction, see xxPath

  property yzPath

    Time function for yz direction, see xxPath

  property zxPath

    Time function for zx direction, see xxPath

  property zzPath

    Time function for zz direction, see xxPath

class yade.wrapper.PeriIsoCompressor(inherits BoundaryController → GlobalEngine → Engine → Serializable)

  Compress/decompress cloud of spheres by controlling periodic cell size until it reaches prescribed average stress, then moving to next stress value in given stress series.

  property charLen

    Characteristic length, should be something like mean particle diameter (default -1=invalid value))

  property currUnbalanced

    Current value of unbalanced force

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property doneHook

    Python command to be run when reaching the last specified stress

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property globalUpdateInt

    how often to recompute average stress, stiffness and unbalanced force

  property keepProportions

    Exactly keep proportions of the cell (stress is controlled based on average, not its components

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxSpan

    Maximum body span in terms of bbox, to prevent periodic cell getting too small. (auto-computed)

  property maxUnbalanced

    if actual unbalanced force is smaller than this number, the packing is considered stable,

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property sigma

    Current stress value

  property state

    Where are we at in the stress series

  property stresses

    Stresses that should be reached, one after another

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.PeriTriaxController(inherits BoundaryController → GlobalEngine → Engine → Serializable)

  Engine for independently controlling stress or strain in periodic simulations.

  > PeriTriaxController.goal contains absolute values for the controlled quantity, and PeriTriaxController.stressMask determines meaning of those values (0 for strain, 1 for stress): e.g. `( 1<<0 | 1<<2 ) = 1 | 4 = 5` means that `goal[0]` and `goal[2]` are stress values, and `goal[1]` is strain.

  See scripts/test/periodic-triax.py for a simple example.

  property absStressTol

    Absolute stress tolerance with respect to `goal`.

  property currUnbalanced

    current unbalanced force (updated every globUpdate) (auto-updated)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property doneHook

    python command to be run when the desired state is reached

  property dynCell

    Imposed stress can be controlled using the packing stiffness (dynCell = False) or by applying the laws of dynamic (dynCell=true). Don’t forget to assign a mass to the cell.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property externalWork

    Work input from boundary controller.

  property globUpdate

    How often to recompute average stress, stiffness and unbalaced force.

  property goal

    Desired stress or strain values (depending on stressMask), strains defined as `strain(i)=log(Fii)` with `Fii` the cell transformation matrix.

    Warning

    Strains are relative to the O.cell.refSize (reference cell size), not the current one (e.g. at the moment when the new strain value is set).

  property growDamping

    Damping of cell resizing (0=perfect control, 1=no control at all); see also `wallDamping` in TriaxialStressController.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mass

    Mass of the cell (user set); if not set and dynCell is used, it will be computed as the sum of all particle masses.

  property maxBodySpan

    maximum body dimension (auto-computed)

  property maxStrainRate

    Maximum strain rate of the periodic cell.

  property maxUnbalanced

    maximum unbalanced force.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property prevGrow

    previous cell grow

  property relStressTol

    Relative stress tolerance with respect to `goal`.

  property stiff

    average stiffness (only every globUpdate steps recomputed from interactions) (auto-updated)

  property strain

    Cell true strain (auto-updated)

  property strainRate

    cell strain rate (auto-updated)

  property stress

    diagonal terms of the stress tensor

  property stressMask

    mask determining strain/stress (0/1) meaning for goal components

  property stressTensor

    average stresses, updated at every step (only every globUpdate steps recomputed from interactions if !dynCell)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ThreeDTriaxialEngine(inherits TriaxialStressController → BoundaryController → GlobalEngine → Engine → Serializable)

  The engine perform a triaxial compression with a control in direction ‘i’ in stress (if stressControl_i) else in strain.

  For a stress control the imposed stress is specified by ‘sigma_i’ with a ‘max_veli’ depending on ‘strainRatei’. To obtain the same strain rate in stress control than in strain control you need to set ‘wallDamping = 0.8’. For a strain control the imposed strain is specified by ‘strainRatei’. With this engine you can also perform internal compaction by growing the size of particles by using `TriaxialStressController::controlInternalStress`. For that, just switch on ‘internalCompaction=1’ and fix sigma_iso=value of mean pressure that you want at the end of the internal compaction.

  Warning

  This engine is deprecated, please switch to TriaxialStressController if you expect long term support.

  property Key

    A string appended at the end of all files, use it to name simulations.

  property UnbalancedForce

    mean resultant forces divided by mean contact force

  property boxVolume

    Total packing volume.

  property computeStressStrainInterval

  property currentStrainRate1

    current strain rate in direction 1 - converging to ThreeDTriaxialEngine::strainRate1 (./s)

  property currentStrainRate2

    current strain rate in direction 2 - converging to ThreeDTriaxialEngine::strainRate2 (./s)

  property currentStrainRate3

    current strain rate in direction 3 - converging to ThreeDTriaxialEngine::strainRate3 (./s)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  property depth

    size of the box (2-axis) (auto-updated)

  property depth0

    Reference size for strain definition. See TriaxialStressController::depth

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property externalWork

    Mechanical work associated to the boundary conditions, i.e. \(\int_{\partial \Omega} \mat{T} \cdot \mat{u} ds\) with \(\mat{T}\) the surface traction and \(\mat{u}\) the displacement at the boundary. (auto-updated)

  property finalMaxMultiplier

    max multiplier of diameters during internal compaction (secondary precise adjustment - TriaxialStressController::maxMultiplier is used in the initial stage)

  property frictionAngleDegree

    Value of friction used in the simulation if (updateFrictionAngle)

  property goal1

    prescribed stress/strain rate on axis 0, as defined by TriaxialStressController::stressMask

  property goal2

    prescribed stress/strain rate on axis 1, as defined by TriaxialStressController::stressMask

  property goal3

    prescribed stress/strain rate on axis 2, as defined by TriaxialStressController::stressMask

  property height

    size of the box (1-axis) (auto-updated)

  property height0

    Reference size for strain definition. See TriaxialStressController::height

  property internalCompaction

    Switch between ‘external’ (walls) and ‘internal’ (growth of particles) compaction.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxMultiplier

    max multiplier of diameters during internal compaction (initial fast increase - TriaxialStressController::finalMaxMultiplier is used in a second stage)

  property max_vel

    Order of magnitude of maximum allowed walls velocity during stress control [m/s]. The corresponding value superseeds the one assigned by the stress controller if the later is higher. max_vel can be set to infinity in many cases, but sometimes helps stabilizing packings. Based on this value, different maxima are computed for each axis based on the dimensions of the sample, so that if each boundary moves at its maximum velocity, the strain rate will be isotropic (see e.g. TriaxialStressController::max_vel1).

  property max_vel1

    Order of magnitude of maximum velocity during stress control for boundaries normal to axis 0, see TriaxialStressController::max_vel (auto-computed)

  property max_vel2

    Order of magnitude of maximum velocity during stress control for boundaries normal to axis 1, see TriaxialStressController::max_vel (auto-computed)

  property max_vel3

    Order of magnitude of maximum velocity during stress control for boundaries normal to axis 2, see TriaxialStressController::max_vel (auto-computed)

  property meanStress

    Mean stress in the packing. (auto-updated)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property particlesVolume

    Total volume of particles (clumps and dynamic spheres). (auto-computed)

  property porosity

    Porosity of the packing, computed from particlesVolume and boxVolume. (auto-updated)

  property previousMultiplier

    (auto-updated)

  property previousStress

    (auto-updated)

  property radiusControlInterval

  setContactProperties((ThreeDTriaxialEngine)arg1, (float)arg2) → None :

    Assign a new friction angle (degrees) to dynamic bodies and relative interactions

  property spheresVolume

    Shorthand for TriaxialStressController::particlesVolume

  property stiffnessUpdateInterval

    iteration period for measuring the resultant packing-boundaries stiffnesses, for stress servo-control

  property strain

    Current strain in a vector (exx,eyy,ezz). The values reflect true (logarithmic) strain.

  property strainDamping

    factor used for smoothing changes in effective strain rate. If target rate is TR, then (1-damping)*(TR-currentRate) will be added at each iteration. With damping=0, rate=target all the time. With damping=1, it doesn’t change.

  strainRate((TriaxialStressController)arg1) → yade._minieigenHP.Vector3 :

    Current strain rate in a vector d/dt(exx,eyy,ezz).

  property strainRate1

    target strain rate in direction 1 (./s, >0 for compression)

  property strainRate2

    target strain rate in direction 2 (./s, >0 for compression)

  property strainRate3

    target strain rate in direction 3 (./s, >0 for compression)

  stress((TriaxialStressController)arg1, (int)id) → yade._minieigenHP.Vector3 :

    Returns the average stress on boundary ‘id’. Here, ‘id’ refers to the internal numbering of boundaries, between 0 and 5.

  property stressControl_1

    Switch to choose a stress or a strain control in directions 1

  property stressControl_2

    Switch to choose a stress or a strain control in directions 2

  property stressControl_3

    Switch to choose a stress or a strain control in directions 3

  property stressDamping

    wall damping coefficient for the stress control - wallDamping=0 implies a (theoretical) perfect control, wallDamping=1 means no movement

  property stressMask

    Bitmask determining wether the imposed goal values are stresses (0 for none, 7 for all, 1 for direction 1, 5 for directions 1 and 3, etc.) or strain rates

  property thickness

    thickness of boxes (needed by some functions)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updateFrictionAngle

    Switch to activate the update of the intergranular frictionto the value ThreeDTriaxialEngine::frictionAngleDegree.

  property updatePorosity

    If true, solid volume will be updated once (will automatically reset to false after one calculation step) e.g. for porosity calculation purpose. Can be used when volume of particles changes during the simulation (e.g. when particles are erased or when clumps are created).

  property volumetricStrain

    Volumetric strain (see TriaxialStressController::strain). (auto-updated)

  property wall_back_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_back_id

    id of boundary ; coordinate 2- (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_bottom_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_bottom_id

    id of boundary ; coordinate 1- (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_front_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_front_id

    id of boundary ; coordinate 2+ (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_left_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_left_id

    id of boundary ; coordinate 0- (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_right_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_right_id

    id of boundary ; coordinate 0+ (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_top_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_top_id

    id of boundary ; coordinate 1+ (default value is ok if aabbWalls are appended BEFORE spheres.)

  property width

    size of the box (0-axis) (auto-updated)

  property width0

    Reference size for strain definition. See TriaxialStressController::width

class yade.wrapper.TriaxialCompressionEngine(inherits TriaxialStressController → BoundaryController → GlobalEngine → Engine → Serializable)

  The engine is a state machine with the following states; transitions my be automatic, see below.

  1. STATE_ISO_COMPACTION: isotropic compaction (compression) until the prescribed mean pressue sigmaIsoCompaction is reached and the packing is stable. The compaction happens either by straining the walls (!internalCompaction) or by growing size of grains (internalCompaction).

  2. STATE_ISO_UNLOADING: isotropic unloading from the previously reached state, until the mean pressure sigmaLateralConfinement is reached (and stabilizes).

     > Note

     > this state will be skipped if sigmaLateralConfinement == sigmaIsoCompaction.

  3. STATE_TRIAX_LOADING: confined uniaxial compression: constant sigmaLateralConfinement is kept at lateral walls (left, right, front, back), while top and bottom walls load the packing in their axis (by straining), until the value of epsilonMax (deformation along the loading axis) is reached. At this point, the simulation is stopped.

  4. STATE_FIXED_POROSITY_COMPACTION: isotropic compaction (compression) until a chosen porosity value (parameter:fixedPorosity). The six walls move with a chosen translation speed (parameter StrainRate).

  5. STATE_TRIAX_LIMBO: currently unused, since simulation is hard-stopped in the previous state.

  Transition from COMPACTION to UNLOADING is done automatically if autoUnload==true;

  > Transition from (UNLOADING to LOADING) or from (COMPACTION to LOADING: if UNLOADING is skipped) is done automatically if autoCompressionActivation=true; Both autoUnload and autoCompressionActivation are true by default.

  Note

  Most of the algorithms used have been developed initialy for simulations reported in [Chareyre2002a] and [Chareyre2005]. They have been ported to Yade in a second step and used in e.g. [Kozicki2008],[Scholtes2009b]_,[Jerier2010b].

  Warning

  This engine is deprecated, please switch to TriaxialStressController if you expect long term support.

  property Key

    A string appended at the end of all files, use it to name simulations.

  property StabilityCriterion

    tolerance in terms of TriaxialCompressionEngine::UnbalancedForce to consider the packing is stable

  property UnbalancedForce

    mean resultant forces divided by mean contact force

  property autoCompressionActivation

    Auto-switch from isotropic compaction (or unloading state if sigmaLateralConfinement<sigmaIsoCompaction) to deviatoric loading

  property autoStopSimulation

    Stop the simulation when the sample reach STATE_LIMBO, or keep running

  property autoUnload

    Auto-switch from isotropic compaction to unloading

  property boxVolume

    Total packing volume.

  property computeStressStrainInterval

  property currentState

    There are 5 possible states in which TriaxialCompressionEngine can be. See above wrapper.TriaxialCompressionEngine

  property currentStrainRate

    current strain rate - converging to TriaxialCompressionEngine::strainRate (./s)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  property depth

    size of the box (2-axis) (auto-updated)

  property depth0

    Reference size for strain definition. See TriaxialStressController::depth

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property epsilonMax

    Value of axial deformation for which the loading must stop

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property externalWork

    Mechanical work associated to the boundary conditions, i.e. \(\int_{\partial \Omega} \mat{T} \cdot \mat{u} ds\) with \(\mat{T}\) the surface traction and \(\mat{u}\) the displacement at the boundary. (auto-updated)

  property finalMaxMultiplier

    max multiplier of diameters during internal compaction (secondary precise adjustment - TriaxialStressController::maxMultiplier is used in the initial stage)

  property fixedPoroCompaction

    A special type of compaction with imposed final porosity TriaxialCompressionEngine::fixedPorosity (WARNING : can give unrealistic results!)

  property fixedPorosity

    Value of porosity chosen by the user

  property frictionAngleDegree

    Value of friction assigned just before the deviatoric loading

  property goal1

    prescribed stress/strain rate on axis 0, as defined by TriaxialStressController::stressMask

  property goal2

    prescribed stress/strain rate on axis 1, as defined by TriaxialStressController::stressMask

  property goal3

    prescribed stress/strain rate on axis 2, as defined by TriaxialStressController::stressMask

  property height

    size of the box (1-axis) (auto-updated)

  property height0

    Reference size for strain definition. See TriaxialStressController::height

  property internalCompaction

    Switch between ‘external’ (walls) and ‘internal’ (growth of particles) compaction.

  property isAxisymetric

    if true, sigma_iso is assigned to sigma1, 2 and 3 (applies at each iteration and overrides user-set values of s1,2,3)

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxMultiplier

    max multiplier of diameters during internal compaction (initial fast increase - TriaxialStressController::finalMaxMultiplier is used in a second stage)

  property maxStress

    Max absolute value of axial stress during the simulation (for post-processing)

  property max_vel

    Order of magnitude of maximum allowed walls velocity during stress control [m/s]. The corresponding value superseeds the one assigned by the stress controller if the later is higher. max_vel can be set to infinity in many cases, but sometimes helps stabilizing packings. Based on this value, different maxima are computed for each axis based on the dimensions of the sample, so that if each boundary moves at its maximum velocity, the strain rate will be isotropic (see e.g. TriaxialStressController::max_vel1).

  property max_vel1

    Order of magnitude of maximum velocity during stress control for boundaries normal to axis 0, see TriaxialStressController::max_vel (auto-computed)

  property max_vel2

    Order of magnitude of maximum velocity during stress control for boundaries normal to axis 1, see TriaxialStressController::max_vel (auto-computed)

  property max_vel3

    Order of magnitude of maximum velocity during stress control for boundaries normal to axis 2, see TriaxialStressController::max_vel (auto-computed)

  property meanStress

    Mean stress in the packing. (auto-updated)

  property noFiles

    If true, no files will be generated (*.xml, *.spheres,…)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property particlesVolume

    Total volume of particles (clumps and dynamic spheres). (auto-computed)

  property porosity

    Porosity of the packing, computed from particlesVolume and boxVolume. (auto-updated)

  property previousMultiplier

    (auto-updated)

  property previousSigmaIso

    Previous value of inherited sigma_iso (used to detect manual changes of the confining pressure)

  property previousState

    Previous state (used to detect manual changes of the state in .xml)

  property previousStress

    (auto-updated)

  property radiusControlInterval

  setContactProperties((TriaxialCompressionEngine)arg1, (float)arg2) → None :

    Assign a new friction angle (degrees) to dynamic bodies and relative interactions

  property sigmaIsoCompaction

    Prescribed isotropic pressure during the compaction phase (< 0 for real - compressive - compaction)

  property sigmaLateralConfinement

    Prescribed confining pressure in the deviatoric loading (< 0 for classical compressive cases); might be different from TriaxialCompressionEngine::sigmaIsoCompaction

  property sigma_iso

    prescribed confining stress (see :yref:TriaxialCompressionEngine::isAxisymetric`)

  property spheresVolume

    Shorthand for TriaxialStressController::particlesVolume

  property stiffnessUpdateInterval

    iteration period for measuring the resultant packing-boundaries stiffnesses, for stress servo-control

  property strain

    Current strain in a vector (exx,eyy,ezz). The values reflect true (logarithmic) strain.

  property strainDamping

    coefficient used for smoother transitions in the strain rate. The rate reaches the target value like \(d^n\) reaches 0, where \(d\) is the damping coefficient and \(n\) is the number of steps

  property strainRate

    target strain rate (./s, >0 for compression)

  stress((TriaxialStressController)arg1, (int)id) → yade._minieigenHP.Vector3 :

    Returns the average stress on boundary ‘id’. Here, ‘id’ refers to the internal numbering of boundaries, between 0 and 5.

  property stressDamping

    wall damping coefficient for the stress control - wallDamping=0 implies a (theoretical) perfect control, wallDamping=1 means no movement

  property stressMask

    Bitmask determining wether the imposed goal values are stresses (0 for none, 7 for all, 1 for direction 1, 5 for directions 1 and 3, etc.) or strain rates

  property testEquilibriumInterval

    interval of checks for transition between phases, higher than 1 saves computation time.

  property thickness

    thickness of boxes (needed by some functions)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property translationAxis

    compression axis

  property uniaxialEpsilonCurr

    Current value of axial deformation during confined loading (is reference to strain[1])

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updatePorosity

    If true, solid volume will be updated once (will automatically reset to false after one calculation step) e.g. for porosity calculation purpose. Can be used when volume of particles changes during the simulation (e.g. when particles are erased or when clumps are created).

  property volumetricStrain

    Volumetric strain (see TriaxialStressController::strain). (auto-updated)

  property wall_back_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_back_id

    id of boundary ; coordinate 2- (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_bottom_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_bottom_id

    id of boundary ; coordinate 1- (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_front_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_front_id

    id of boundary ; coordinate 2+ (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_left_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_left_id

    id of boundary ; coordinate 0- (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_right_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_right_id

    id of boundary ; coordinate 0+ (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_top_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_top_id

    id of boundary ; coordinate 1+ (default value is ok if aabbWalls are appended BEFORE spheres.)

  property warn

    counter used for sending a deprecation warning once

  property width

    size of the box (0-axis) (auto-updated)

  property width0

    Reference size for strain definition. See TriaxialStressController::width

class yade.wrapper.TriaxialStressController(inherits BoundaryController → GlobalEngine → Engine → Serializable)

  An engine maintaining constant stresses or constant strain rates on some boundaries of a parallepipedic packing. The stress/strain control is defined for each axis using TriaxialStressController::stressMask (a bitMask) and target values are defined by goal1,goal2, and goal3. The sign conventions of continuum mechanics are used for strains and stresses (positive traction).

  Note

  The algorithms used have been developed initialy for simulations reported in [Chareyre2002a] and [Chareyre2005]. They have been ported to Yade in a second step and used in e.g. [Kozicki2008],[Scholtes2009b]_,[Jerier2010b].

  property boxVolume

    Total packing volume.

  property computeStressStrainInterval

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  property depth

    size of the box (2-axis) (auto-updated)

  property depth0

    Reference size for strain definition. See TriaxialStressController::depth

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property externalWork

    Mechanical work associated to the boundary conditions, i.e. \(\int_{\partial \Omega} \mat{T} \cdot \mat{u} ds\) with \(\mat{T}\) the surface traction and \(\mat{u}\) the displacement at the boundary. (auto-updated)

  property finalMaxMultiplier

    max multiplier of diameters during internal compaction (secondary precise adjustment - TriaxialStressController::maxMultiplier is used in the initial stage)

  property goal1

    prescribed stress/strain rate on axis 0, as defined by TriaxialStressController::stressMask

  property goal2

    prescribed stress/strain rate on axis 1, as defined by TriaxialStressController::stressMask

  property goal3

    prescribed stress/strain rate on axis 2, as defined by TriaxialStressController::stressMask

  property height

    size of the box (1-axis) (auto-updated)

  property height0

    Reference size for strain definition. See TriaxialStressController::height

  property internalCompaction

    Switch between ‘external’ (walls) and ‘internal’ (growth of particles) compaction.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxMultiplier

    max multiplier of diameters during internal compaction (initial fast increase - TriaxialStressController::finalMaxMultiplier is used in a second stage)

  property max_vel

    Order of magnitude of maximum allowed walls velocity during stress control [m/s]. The corresponding value superseeds the one assigned by the stress controller if the later is higher. max_vel can be set to infinity in many cases, but sometimes helps stabilizing packings. Based on this value, different maxima are computed for each axis based on the dimensions of the sample, so that if each boundary moves at its maximum velocity, the strain rate will be isotropic (see e.g. TriaxialStressController::max_vel1).

  property max_vel1

    Order of magnitude of maximum velocity during stress control for boundaries normal to axis 0, see TriaxialStressController::max_vel (auto-computed)

  property max_vel2

    Order of magnitude of maximum velocity during stress control for boundaries normal to axis 1, see TriaxialStressController::max_vel (auto-computed)

  property max_vel3

    Order of magnitude of maximum velocity during stress control for boundaries normal to axis 2, see TriaxialStressController::max_vel (auto-computed)

  property meanStress

    Mean stress in the packing. (auto-updated)

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property particlesVolume

    Total volume of particles (clumps and dynamic spheres). (auto-computed)

  property porosity

    Porosity of the packing, computed from particlesVolume and boxVolume. (auto-updated)

  property previousMultiplier

    (auto-updated)

  property previousStress

    (auto-updated)

  property radiusControlInterval

  property spheresVolume

    Shorthand for TriaxialStressController::particlesVolume

  property stiffnessUpdateInterval

    iteration period for measuring the resultant packing-boundaries stiffnesses, for stress servo-control

  property strain

    Current strain in a vector (exx,eyy,ezz). The values reflect true (logarithmic) strain.

  property strainDamping

    coefficient used for smoother transitions in the strain rate. The rate reaches the target value like \(d^n\) reaches 0, where \(d\) is the damping coefficient and \(n\) is the number of steps

  strainRate((TriaxialStressController)arg1) → yade._minieigenHP.Vector3 :

    Current strain rate in a vector d/dt(exx,eyy,ezz).

  stress((TriaxialStressController)arg1, (int)id) → yade._minieigenHP.Vector3 :

    Returns the average stress on boundary ‘id’. Here, ‘id’ refers to the internal numbering of boundaries, between 0 and 5.

  property stressDamping

    wall damping coefficient for the stress control - wallDamping=0 implies a (theoretical) perfect control, wallDamping=1 means no movement

  property stressMask

    Bitmask determining wether the imposed goal values are stresses (0 for none, 7 for all, 1 for direction 1, 5 for directions 1 and 3, etc.) or strain rates

  property thickness

    thickness of boxes (needed by some functions)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updatePorosity

    If true, solid volume will be updated once (will automatically reset to false after one calculation step) e.g. for porosity calculation purpose. Can be used when volume of particles changes during the simulation (e.g. when particles are erased or when clumps are created).

  property volumetricStrain

    Volumetric strain (see TriaxialStressController::strain). (auto-updated)

  property wall_back_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_back_id

    id of boundary ; coordinate 2- (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_bottom_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_bottom_id

    id of boundary ; coordinate 1- (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_front_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_front_id

    id of boundary ; coordinate 2+ (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_left_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_left_id

    id of boundary ; coordinate 0- (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_right_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_right_id

    id of boundary ; coordinate 0+ (default value is ok if aabbWalls are appended BEFORE spheres.)

  property wall_top_activated

    if true, this wall moves according to the target value (stress or strain rate).

  property wall_top_id

    id of boundary ; coordinate 1+ (default value is ok if aabbWalls are appended BEFORE spheres.)

  property width

    size of the box (0-axis) (auto-updated)

  property width0

    Reference size for strain definition. See TriaxialStressController::width

class yade.wrapper.UniaxialStrainer(inherits BoundaryController → GlobalEngine → Engine → Serializable)

  Axial displacing two groups of bodies in the opposite direction with given strain rate.

  property absSpeed

    alternatively, absolute speed of boundary motion can be specified; this is effective only at the beginning and if strainRate is not set; changing absSpeed directly during simulation wil have no effect. [ms⁻¹]

  property active

    Whether this engine is activated

  property asymmetry

    If 0, straining is symmetric for negIds and posIds; for 1 (or -1), only posIds are strained and negIds don’t move (or vice versa)

  property avgStress

    Current average stress (auto-updated) [Pa]

  property axis

    The axis which is strained (0,1,2 for x,y,z)

  property blockDisplacements

    Whether displacement of boundary bodies perpendicular to the strained axis are blocked or are free

  property blockRotations

    Whether rotations of boundary bodies are blocked.

  property crossSectionArea

    crossSection perpendicular to he strained axis; must be given explicitly [m²]

  property currentStrainRate

    Current strain rate (update automatically). (auto-updated)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property idleIterations

    Number of iterations that will pass without straining activity after stopStrain has been reached

  property initAccelTime

    Time for strain reaching the requested value (linear interpolation). If negative, the time is dt*(-initAccelTime), where dt is the timestep at the first iteration. [s]

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property limitStrain

    Invert the sense of straining (sharply, without transition) one this value of strain is reached. Not effective if 0.

  property negIds

    Bodies on which strain will be applied (on the negative end along the axis)

  property notYetReversed

    Flag whether the sense of straining has already been reversed (only used internally).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property originalLength

    Distance of reference bodies in the direction of axis before straining started (computed automatically) [m]

  property posIds

    Bodies on which strain will be applied (on the positive end along the axis)

  property setSpeeds

    should we set speeds at the beginning directly, instead of increasing strain rate progressively?

  property stopStrain

    Strain at which we will pause simulation; inactive (nan) by default; must be reached from below (in absolute value)

  property strain

    Current strain value, elongation/originalLength (auto-updated) [-]

  property strainRate

    Rate of strain, starting at 0, linearly raising to strainRate. [-]

  property stressUpdateInterval

    How often to recompute stress on supports.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.VESupportEngine(inherits BoundaryController → GlobalEngine → Engine → Serializable)

  Engine that constraints given bodies in place (refPos) with a visco-elastic constrain according to the Burgers model.

  Burger’s rheological scheme with adopted designations.

  The model of applied constraint can be degenerated to simpler models. Passing negative value of the damping coefficient turns off the corresponding dashpot. A negative value of c2, turns off the whole Kelvin-Voigt branch. By default c1=c2=-1, and model is simplified to an elastic boundary condition. Hence, it can be used as Winkler foundation.

  Potential applicatons are presented in [Brzezinski2022], and examples section (see examples/viscoelastic-supports/single-element.py, and examples/viscoelastic-supports/discrete-foundation.py

  property bIds

    IDs of bodies that should be attached to supports.

  property c1

    Damping coeff. of dashpot #1 (the one in Maxwell branch). Negative value turns off the dashpot. [N*s/m]

  property c2

    Damping coeff. of dashpot #2 (the one in Kelvin-Voigt branch). Negative value turns off whole Kelvin-Voigt branch. [N*s/m]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property k1

    Stiffness of spring #1 (the one in Maxwell branch) [N/m]

  property k2

    Stiffness of spring #2 (the one in Kelvin-Voigt branch) [N/m]

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### Collider

Inheritance graph of Collider.

class yade.wrapper.Collider(inherits GlobalEngine → Engine → Serializable)

  Abstract class for finding spatial collisions between bodies.

  Special constructor

  Derived colliders (unless they override `pyHandleCustomCtorArgs`) can be given list of BoundFunctors which is used to initialize the internal boundDispatcher instance.

  property avoidSelfInteractionMask

    This mask is used to avoid the interactions inside a group of particles. To do so, the particles must have the exact same mask and that mask should have one bit in common with this avoidSelfInteractionMask as for their binary representations.

  property boundDispatcher

    BoundDispatcher object that is used for creating bounds on collider’s request as necessary.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.FlatGridCollider(inherits Collider → GlobalEngine → Engine → Serializable)

  Non-optimized grid collider, storing grid as dense flat array. Each body is assigned to (possibly multiple) cells, which are arranged in regular grid between aabbMin and aabbMax, with cell size step (same in all directions). Bodies outsize (aabbMin, aabbMax) are handled gracefully, assigned to closest cells (this will create spurious potential interactions). verletDist determines how much is each body enlarged to avoid collision detection at every step.

  Note

  This collider keeps all cells in linear memory array, therefore will be memory-inefficient for sparse simulations.

  Warning

  objects Body::bound are not used, BoundFunctors are not used either: assigning cells to bodies is hard-coded internally. Currently handles Shapes are: Sphere.

  Note

  Periodic boundary is not handled (yet).

  property aabbMax

    Upper corner of grid (approximate, might be rouded up to minStep.

  property aabbMin

    Lower corner of grid.

  property avoidSelfInteractionMask

    This mask is used to avoid the interactions inside a group of particles. To do so, the particles must have the exact same mask and that mask should have one bit in common with this avoidSelfInteractionMask as for their binary representations.

  property boundDispatcher

    BoundDispatcher object that is used for creating bounds on collider’s request as necessary.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property step

    Step in the grid (cell size)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property verletDist

    Length by which enlarge space occupied by each particle; avoids running collision detection at every step.

class yade.wrapper.GeneralIntegratorInsertionSortCollider(inherits InsertionSortCollider → Collider → GlobalEngine → Engine → Serializable)

  This class is the adaptive version of the InsertionSortCollider and changes the NewtonIntegrator dependency of the collider algorithms to the Integrator interface which is more general.

  property allowBiggerThanPeriod

    If true, tests on bodies sizes will be disabled, and the simulation will run normaly even if bodies larger than period are found. It can be useful when the periodic problem include e.g. a floor modelized with wall/box/facet. Be sure you know what you are doing if you touch this flag. The result is undefined if one large body moves out of the (0,0,0) period.

  property avoidSelfInteractionMask

    This mask is used to avoid the interactions inside a group of particles. To do so, the particles must have the exact same mask and that mask should have one bit in common with this avoidSelfInteractionMask as for their binary representations.

  property boundDispatcher

    BoundDispatcher object that is used for creating bounds on collider’s request as necessary.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property doSort

    Do forced resorting of interactions.

  dumpBounds((InsertionSortCollider)arg1) → tuple :

    Return representation of the internal sort data. The format is `([...],[...],[...])` for 3 axes, where each `...` is a list of entries (bounds). The entry is a tuple with the fllowing items:

    - coordinate (float)

    - body id (int), but negated for negative bounds

    - period numer (int), if the collider is in the periodic regime.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property fastestBodyMaxDist

    Normalized maximum displacement of the fastest body since last run; if >= 1, we could get out of bboxes and will trigger full run. (auto-updated)

  isActivated((InsertionSortCollider)arg1) → bool :

    Return true if collider needs execution at next iteration.

  property keepListsShort

    if true remove bounds of non-existent or unbounded bodies from the lists (auto-updated); turned true automatically in MPI mode and if bodies are erased with BodyContainer.enableRedirection`=True. :ydefault:`false

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property minSweepDistFactor

    Minimal distance by which enlarge all bounding boxes; superseeds computed value of verletDist when lower that (minSweepDistFactor x verletDist).

  property newton

    reference to active Newton integrator. (auto-updated)

  property numAction

    Cummulative number of collision detection.

  property numReinit

    Cummulative number of bound array re-initialization.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property overlapTolerance

    Tolerance on determining overlap. In rare cases different parts of the code can inconsistently lead to different results in terms of overlap, with false negative by spatialOverlapPeri possibly leading to nasty bugs in contact detection (false positive are harmless). This tolerance is to avoid false negative, the value can be understood as relative to 1 (i.e. independent of particle size or any other reference length). The default should be ok.

  property periodic

    Whether the collider is in periodic mode (read-only; for debugging) (auto-updated)

  property smartInsertErase

    Use an algorithm optimized for heavy insert/delete (avoid initSort) - experimental.

  property sortAxis

    Axis for the initial contact detection.

  property sortThenCollide

    Separate sorting and colliding phase; it is MUCH slower, but all interactions are processed at every step; this effectively makes the collider non-persistent, not remembering last state. (The default behavior relies on the fact that inversions during insertion sort are overlaps of bounding boxes that just started/ceased to exist, and only processes those; this makes the collider much more efficient.)

  property strideActive

    Whether striding is active (read-only; for debugging). (auto-updated)

  property targetInterv

    (experimental) Target number of iterations between bound update, used to define a smaller sweep distance for slower grains if >0, else always use 1*verletDist. Useful in simulations with strong velocity contrasts between slow bodies and fast bodies.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updatingDispFactor

    (experimental) Displacement factor used to trigger bound update: the bound is updated only if updatingDispFactor*disp>sweepDist when >0, else all bounds are updated.

  property verletDist

    Length by which to enlarge particle bounds, to avoid running collider at every step. Stride disabled if zero. Negative value will trigger automatic computation, so that the real value will be verletDist × minimum spherical particle radius; if there are no spherical particles, it will be disabled. The actual length added to one bound can be only a fraction of verletDist when InsertionSortCollider::targetInterv is > 0.

class yade.wrapper.InsertionSortCollider(inherits Collider → GlobalEngine → Engine → Serializable)

  Collider with O(n log(n)) complexity, using Aabb for bounds.

  At the initial step, Bodies’ bounds (along sortAxis) are first std::sort’ed along this (sortAxis) axis, then collided. The initial sort has \(O(n^2)\) complexity, see Colliders’ performance for some information (There are scripts in examples/collider-perf for measurements).

  Insertion sort is used for sorting the bound list that is already pre-sorted from last iteration, where each inversion calls checkOverlap which then handles either overlap (by creating interaction if necessary) or its absence (by deleting interaction if it is only potential).

  Bodies without bounding volume (such as clumps) are handled gracefully and never collide. Deleted bodies are handled gracefully as well.

  This collider handles periodic boundary conditions. There are some limitations, notably:

  > 1. No body can have Aabb larger than cell’s half size in that respective dimension. You get exception if it does and gets in interaction. One way to explicitly by-pass this restriction is offered by `allowBiggerThanPeriod`, which can be turned on to insert a floor in the form of a very large box for instance (see examples/periodicSandPile.py).

  > 2. No body can travel more than cell’s distance in one step; this would mean that the simulation is numerically exploding, and it is only detected in some cases.

  Stride can be used to avoid running collider at every step by enlarging the particle’s bounds, tracking their displacements and only re-run if they might have gone out of that bounds (see Verlet list for brief description and background) . This requires cooperation from NewtonIntegrator as well as BoundDispatcher, which will be found among engines automatically (exception is thrown if they are not found).

  If you wish to use strides, set `verletDist` (length by which bounds will be enlarged in all directions) to some value, e.g. 0.05 × typical particle radius. This parameter expresses the tradeoff between many potential interactions (running collider rarely, but with longer exact interaction resolution phase) and few potential interactions (running collider more frequently, but with less exact resolutions of interactions); it depends mainly on packing density and particle radius distribution.

  If `targetInterv` is >1, not all particles will have their bound enlarged by `verletDist`; instead, they will have bounds increased by a length in order to trigger a new colliding after `targetInterv` iteration, assuming they move at almost constant velocity. Ideally in this method, all particles would reach their bounds at the sime iteration. This is of course not the case as soon as velocities fluctuate in time. Bound::sweepLength is tuned on the basis of the displacement recorded between the last two runs of the collider. In this situation, `verletDist` defines the maximum sweep length.

  property allowBiggerThanPeriod

    If true, tests on bodies sizes will be disabled, and the simulation will run normaly even if bodies larger than period are found. It can be useful when the periodic problem include e.g. a floor modelized with wall/box/facet. Be sure you know what you are doing if you touch this flag. The result is undefined if one large body moves out of the (0,0,0) period.

  property avoidSelfInteractionMask

    This mask is used to avoid the interactions inside a group of particles. To do so, the particles must have the exact same mask and that mask should have one bit in common with this avoidSelfInteractionMask as for their binary representations.

  property boundDispatcher

    BoundDispatcher object that is used for creating bounds on collider’s request as necessary.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property doSort

    Do forced resorting of interactions.

  dumpBounds((InsertionSortCollider)arg1) → tuple :

    Return representation of the internal sort data. The format is `([...],[...],[...])` for 3 axes, where each `...` is a list of entries (bounds). The entry is a tuple with the fllowing items:

    - coordinate (float)

    - body id (int), but negated for negative bounds

    - period numer (int), if the collider is in the periodic regime.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property fastestBodyMaxDist

    Normalized maximum displacement of the fastest body since last run; if >= 1, we could get out of bboxes and will trigger full run. (auto-updated)

  isActivated((InsertionSortCollider)arg1) → bool :

    Return true if collider needs execution at next iteration.

  property keepListsShort

    if true remove bounds of non-existent or unbounded bodies from the lists (auto-updated); turned true automatically in MPI mode and if bodies are erased with BodyContainer.enableRedirection`=True. :ydefault:`false

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property minSweepDistFactor

    Minimal distance by which enlarge all bounding boxes; superseeds computed value of verletDist when lower that (minSweepDistFactor x verletDist).

  property newton

    reference to active Newton integrator. (auto-updated)

  property numAction

    Cummulative number of collision detection.

  property numReinit

    Cummulative number of bound array re-initialization.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property overlapTolerance

    Tolerance on determining overlap. In rare cases different parts of the code can inconsistently lead to different results in terms of overlap, with false negative by spatialOverlapPeri possibly leading to nasty bugs in contact detection (false positive are harmless). This tolerance is to avoid false negative, the value can be understood as relative to 1 (i.e. independent of particle size or any other reference length). The default should be ok.

  property periodic

    Whether the collider is in periodic mode (read-only; for debugging) (auto-updated)

  property smartInsertErase

    Use an algorithm optimized for heavy insert/delete (avoid initSort) - experimental.

  property sortAxis

    Axis for the initial contact detection.

  property sortThenCollide

    Separate sorting and colliding phase; it is MUCH slower, but all interactions are processed at every step; this effectively makes the collider non-persistent, not remembering last state. (The default behavior relies on the fact that inversions during insertion sort are overlaps of bounding boxes that just started/ceased to exist, and only processes those; this makes the collider much more efficient.)

  property strideActive

    Whether striding is active (read-only; for debugging). (auto-updated)

  property targetInterv

    (experimental) Target number of iterations between bound update, used to define a smaller sweep distance for slower grains if >0, else always use 1*verletDist. Useful in simulations with strong velocity contrasts between slow bodies and fast bodies.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updatingDispFactor

    (experimental) Displacement factor used to trigger bound update: the bound is updated only if updatingDispFactor*disp>sweepDist when >0, else all bounds are updated.

  property verletDist

    Length by which to enlarge particle bounds, to avoid running collider at every step. Stride disabled if zero. Negative value will trigger automatic computation, so that the real value will be verletDist × minimum spherical particle radius; if there are no spherical particles, it will be disabled. The actual length added to one bound can be only a fraction of verletDist when InsertionSortCollider::targetInterv is > 0.

class yade.wrapper.SpatialQuickSortCollider(inherits Collider → GlobalEngine → Engine → Serializable)

  Collider using quicksort along axes at each step, using Aabb bounds.

  Its performance is lower than that of InsertionSortCollider (see Colliders’ performance), but the algorithm is simple enought to make it good for checking other collider’s correctness.

  property avoidSelfInteractionMask

    This mask is used to avoid the interactions inside a group of particles. To do so, the particles must have the exact same mask and that mask should have one bit in common with this avoidSelfInteractionMask as for their binary representations.

  property boundDispatcher

    BoundDispatcher object that is used for creating bounds on collider’s request as necessary.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### FieldApplier

Inheritance graph of FieldApplier.

class yade.wrapper.FieldApplier(inherits GlobalEngine → Engine → Serializable)

  Base for engines applying force files on particles. Not to be used directly.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.AxialGravityEngine(inherits FieldApplier → GlobalEngine → Engine → Serializable)

  Apply acceleration (independent of distance) directed towards an axis.

  property acceleration

    Acceleration magnitude [kgms⁻²]

  property axisDirection

    direction of the gravity axis (will be normalized automatically)

  property axisPoint

    Point through which the axis is passing.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mask

    If mask defined, only bodies with corresponding groupMask will be affected by this engine. If 0, all bodies will be affected.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.CentralConstantAccelerationEngine(inherits FieldApplier → GlobalEngine → Engine → Serializable)

  Engine applying constant acceleration to all bodies, towards a central body. Ignoring the distance between them.

  property accel

    Acceleration magnitude [kgms⁻²]

  property centralBody

    The body towards which all other bodies are attracted.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mask

    If mask defined, only bodies with corresponding groupMask will be affected by this engine. If 0, all bodies will be affected.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property reciprocal

    If true, acceleration will be applied on the central body as well.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GravityEngine(inherits FieldApplier → GlobalEngine → Engine → Serializable)

  Engine applying constant acceleration to all bodies. DEPRECATED, use Newton::gravity unless you need energy tracking or selective gravity application using groupMask).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property gravity

    Acceleration [kgms⁻²]

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mask

    If mask defined, only bodies with corresponding groupMask will be affected by this engine. If 0, all bodies will be affected.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property warnOnce

    For deprecation warning once.

class yade.wrapper.HdapsGravityEngine(inherits GravityEngine → FieldApplier → GlobalEngine → Engine → Serializable)

  Read accelerometer in Thinkpad laptops (HDAPS and accordingly set gravity within the simulation. This code draws from hdaps-gl . See scripts/test/hdaps.py for an example.

  property accel

    reading from the sysfs file

  property calibrate

    Zero position; if NaN, will be read from the hdapsDir / calibrate.

  property calibrated

    Whether calibrate was already updated. Do not set to `True` by hand unless you also give a meaningful value for calibrate.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property gravity

    Acceleration [kgms⁻²]

  property hdapsDir

    Hdaps directory; contains `position` (with accelerometer readings) and `calibration` (zero acceleration).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mask

    If mask defined, only bodies with corresponding groupMask will be affected by this engine. If 0, all bodies will be affected.

  property msecUpdate

    How often to update the reading.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updateThreshold

    Minimum difference of reading from the file before updating gravity, to avoid jitter.

  property warnOnce

    For deprecation warning once.

  property zeroGravity

    Gravity if the accelerometer is in flat (zero) position.

## Partial engines

Inheritance graph of PartialEngine.

class yade.wrapper.PartialEngine(inherits Engine → Serializable)

  Engine affecting only particular bodies in the simulation, namely those defined in ids attribute. See also GlobalEngine.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.BicyclePedalEngine(inherits KinematicEngine → PartialEngine → Engine → Serializable)

  Engine applying the linear motion of `bicycle pedal` e.g. moving points around the axis without rotation

  property angularVelocity

    Angular velocity. [rad/s]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property fi

    Initial phase [radians]

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property radius

    Rotation radius. [m]

  property rotationAxis

    Axis of rotation (direction); will be normalized automatically.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.CombinedKinematicEngine(inherits PartialEngine → Engine → Serializable)

  Engine for applying combined displacements on pre-defined bodies. Constructed using `+` operator on regular KinematicEngines. The `ids` operated on are those of the first engine in the combination (assigned automatically).

  property comb

    Kinematic engines that will be combined by this one, run in the order given.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.DragEngine(inherits PartialEngine → Engine → Serializable)

  Apply drag force on some particles at each step, decelerating them proportionally to their linear velocities. The applied force reads

  \[F_{d}=-\frac{\vec{v}}{|\vec{v}|}\frac{1}{2}\rho|\vec{v}|^2 C_d A\]

  where \(\rho\) is the medium density (density), \(v\) is particle’s velocity, \(A\) is particle projected area (disc), \(C_d\) is the drag coefficient (0.47 for Sphere),

  Note

  Drag force is only applied to spherical particles, listed in ids.

  property Cd

    Drag coefficient <http://en.wikipedia.org/wiki/Drag_coefficient>`_.

  property Rho

    Density of the medium (fluid or air), by default - the density of the air.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ForceEngine(inherits PartialEngine → Engine → Serializable)

  Apply contact force on some particles at each step.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property force

    Force to apply.

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.HarmonicForceEngine(inherits PartialEngine → Engine → Serializable)

  This engine adds a harmonic (sinusoidal) force to a set of bodies. It is identical to HarmonicMotionEngine except a force amplitude is prescribed instead of motion, see also the dynamics of harmonic motion

  property A

    Amplitude [N]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property f

    Frequency [hertz]

  property fi

    Initial phase [radians]. By default, the phase is zero such that the force starts at zero.

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.HarmonicMotionEngine(inherits KinematicEngine → PartialEngine → Engine → Serializable)

  This engine implements the harmonic oscillation of bodies. See also HarmonicForceEngine that applies a harmonic force, see also the dynamics of harmonic motion

  property A

    Amplitude [m]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property f

    Frequency [hertz]

  property fi

    Initial phase [radians]. By default, the body oscillates around initial position.

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.HarmonicRotationEngine(inherits RotationEngine → KinematicEngine → PartialEngine → Engine → Serializable)

  This engine implements the harmonic-rotation oscillation of bodies, see also the dynamics of harmonic motion ; please, set dynamic=False for bodies, droven by this engine, otherwise amplitude will be 2x more, than awaited.

  property A

    Amplitude [rad]

  property angularVelocity

    Angular velocity. [rad/s]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property f

    Frequency [hertz]

  property fi

    Initial phase [radians]. By default, the body oscillates around initial position.

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property rotateAroundZero

    If True, bodies will not rotate around their centroids, but rather around `zeroPoint`.

  property rotationAxis

    Axis of rotation (direction); will be normalized automatically.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property zeroPoint

    Point around which bodies will rotate if `rotateAroundZero` is True

class yade.wrapper.HelixEngine(inherits RotationEngine → KinematicEngine → PartialEngine → Engine → Serializable)

  Engine applying both rotation and translation, along the same axis, whence the name HelixEngine

  property angleTurned

    How much have we turned so far. (auto-updated) [rad]

  property angularVelocity

    Angular velocity. [rad/s]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property linearVelocity

    Linear velocity [m/s]

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property rotateAroundZero

    If True, bodies will not rotate around their centroids, but rather around `zeroPoint`.

  property rotationAxis

    Axis of rotation (direction); will be normalized automatically.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property zeroPoint

    Point around which bodies will rotate if `rotateAroundZero` is True

class yade.wrapper.HydroForceEngine(inherits PartialEngine → Engine → Serializable)
  Engine performing a coupling of the DEM with a volume-averaged 1D fluid resolution to simulate steady uniform unidirectional fluid flow. It has been developed and used to model steady uniform gravity-driven turbulent bedload transport [Maurin2015b] [Maurin2016] [Maurin2018], but can be also used in its current state for laminar or pressure-driven configurations. The fundamentals of the model can be found in [Maurin2015b] and [Maurin2015PhD], and in more details in [Maurin2018_VANSbasis], [Maurin2018_VANSfluidResol] and [Maurin2018_VANSvalidations].

    The engine can be decomposed in three different parts: (i) It applies the fluid force on the particles imposed by the fluid velocity profiles and fluid properties, (ii) It evaluates averaged solid depth profiles necessary for the fluid force application and for the fluid resolution, (iii) It solve the volume-averaged 1D fluid momentum balance.

  The three different functions are detailed below:

  > (i) Fluid force on particles Apply to each particles, buoyancy, drag and lift force due to a 1D fluid flow and can apply lubrication force between two particles. The applied drag force reads

  > \(F_{d}=\frac{1}{2} C_d A\rho^f|\vec{v_f - v}| \vec{v_f - v}\)

  > where \(\rho\) is the fluid density (densFluid), \(v\) is particle’s velocity, \(v_f\) is the velocity of the fluid at the particle center (taken from the fluid velocity profile vxFluid), \(A = \pi d^2/4\) is particle projected area (disc), \(C_d\) is the drag coefficient. The formulation of the drag coefficient depends on the local particle reynolds number and the solid volume fraction. The formulation of the drag is [Dallavalle1948] [RevilBaudard2013] with a correction of Richardson-Zaki [Richardson1954] to take into account the hindrance effect. This law is classical in sediment transport. The possibly activated lubrication force (with parameter:yref:lubrication<HydroForceEngine.lubrication> put to True) reads: \(F_{lubrication} = \frac{6 \pi \eta^f v_rel^n}{\delta^n + \epsilon_r}\), with \(\eta^f\) the fluid dynamic viscosity viscoDyn, \(v_rel^n\) the normal relative velocity of the two particles, \(\delta^n\) the distance between the two particles surface, and \(\epsilon_r\) the roughness scale of the particle (roughnessPartScale).

  It is possible to activate a fluctuation of the drag force for each particle which account for the turbulent fluctuation of the fluid velocity (velFluct). Three simple discrete random walk model have been implemented for the turbulent velocity fluctuation. The main one (turbulentFluctuations) takes as input the Reynolds stress tensor \(R^f_{xz}\) as a function of the depth, and allows to recover the main property of the fluctuations by imposing \(<u_x'u_z'> (z) = <R^f_{xz}>(z)/\rho^f\). It requires as input \(<R^f_{xz}>(z)\) called ReynoldStresses in the code.

    The formulation of the lift is taken from [Wiberg1985] and is such that :

    \(F_{L}=\frac{1}{2} C_L A\rho^f((v_f - v)^2_{top} - (v_f - v)^2_{bottom})\)

    Where the subscript top and bottom means evaluated at the top (respectively the bottom) of the sphere considered. This formulation of the lift account for the difference of pressure at the top and the bottom of the particle inside a turbulent shear flow. As this formulation is controversial when approaching the threshold of motion [Schmeeckle2007] it is possible to desactivate it with the variable lift. The buoyancy is taken into account through the buoyant weight :

    \(F_{buoyancy}= - \rho^f V^p g\)

  , where g is the gravity vector along the vertical, and \(V^p\) is the volume of the particle. In the case where the fluid flow is steady and uniform, the buoyancy reduces to its wall-normal component (see [Maurin2018] for a full explanation), and one should put steadyFlow to true in order to kill the streamwise component.

  > (ii) Averaged solid depth profiles The function averageProfile evaluates the volume averaged depth profiles (1D) of particle velocity, particle solid volume fraction and particle drag force. It uses a volume-weighting average following [Maurin2015PhD]_[Maurin2015b]_, i.e. the average of a variable \(A^p\) associated to particles at a given discretized wall-normal position \(z\) is given by:

  > \(\left< A \right>^s(z) = \displaystyle \frac{\displaystyle \sum_{p|z^p\in[z-dz/2,z+dz/2]} A^p(t) V^p_z}{\displaystyle \sum_{p|z^p\in[z-dz/2,z+dz/2]} V^p_z}\)

  > Where the sums are over the particles contained inside the slice between the wall-normal position \(z-dz/2\) and \(z+dz/2\), and \(V^p\) represents the part of the volume of the given particle effectively contained inside the slice. For more details, see [Maurin2015PhD].

  > (iii) 1D volume-average fluid resolution The fluid resolution is based on the resolution of the 1D volume-averaged fluid momentum balance. It assumes by definition (unidirectional) that the fluid flow is steady and uniform. It is the same fluid resolution as [RevilBaudard2013]. Details can be found in this paper and in [Maurin2015PhD] [Maurin2015b].

  > The three different component can be used independently, e.g. applying a fluid force due to an imposed fluid profile or solving the fluid momentum balance for a given concentration of particles.

  property Cl

    Value of the lift coefficient taken from [Wiberg1985]

  property ReynoldStresses

    Vector of size equal to nCell containing the Reynolds stresses as a function of the depth. ReynoldStresses(z) \(= \rho^f <u_x'u_z'>(z)^2\)

  property averageDrag

    Discretized average drag depth profile. No role in the engine, output parameter. For practical reason, it can be evaluated directly inside the engine, calling from python the averageProfile() method of the engine

  property averageDrag1

    Discretized average drag depth profile of particles of type 1. Evaluated when twoSize is set to True.

  property averageDrag2

    Discretized average drag depth profile of particles of type 2. Evaluated when twoSize is set to True.

  averageProfile((HydroForceEngine)arg1) → None :

    Compute and store the particle velocity (vxPart, vyPart, vzPart) and solid volume fraction (phiPart) depth profile. For each defined cell z, the k component of the average particle velocity reads:

    \(<v_k>^z= \sum_p V^p v_k^p/\sum_p V^p\),

    where the sum is made over the particles contained in the cell, \(v_k^p\) is the k component of the velocity associated to particle p, and \(V^p\) is the part of the volume of the particle p contained inside the cell. This definition allows to smooth the averaging, and is equivalent to taking into account the center of the particles only when there is a lot of particles in each cell. As for the solid volume fraction, it is evaluated in the same way: for each defined cell z, it reads:

    \(<\phi>^z= \frac{1}{V_{cell}}\sum_p V^p\), where \(V_{cell}\) is the volume of the cell considered, and \(V^p\) is the volume of particle p contained in cell z. This function gives depth profiles of average velocity and solid volume fraction, returning the average quantities in each cell of height dz, from the reference horizontal plane at elevation zRef (input parameter) until the plane of elevation zRef plus nCell times deltaZ (input parameters). When the option twoSize is set to True, evaluate in addition the average drag (averageDrag1 and averageDrag2) and solid volume fraction (phiPart1 and phiPart2) depth profiles considering only the particles of radius respectively radiusPart1 and radiusPart2 in the averaging.

  property bedElevation

    Elevation of the bed above which the fluid flow is turbulent and the particles undergo turbulent velocity fluctuation.

  property channelWidth

    Fluid resolution: Channel width for the evaluation of the fluid wall friction inside the fluid resolution.

  property compatibilityOldVersion

    Option to make HydroForceEngine compatible with former scripts. Slow down slightly the calculation and will eventually be removed.

  computeRadiusParts((HydroForceEngine)arg1) → None :

    compute the different class of radius present in the simulation.

  property convAcc

    Convective acceleration, depth dependent

  property convAccOption

    To activate the convective acceleration option in order to account for a convective acceleration term inside the momentum balance.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  property deltaZ

    Height of the discretization cell.

  property densFluid

    Density of the fluid, by default - density of water

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property dpdx

    pressure gradient along streamwise direction

  property dtFluct

    Execution time step of the turbulent fluctuation model.

  property enableMultiClassAverage

    Enables specific averaging for all the different particle size. Uses a lot of memory if using a lots of different particle size

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property expoRZ

    Value of the Richardson-Zaki exponent, for the drag correction due to hindrance

  property fluctTime

    Vector containing the time of life of the fluctuations associated to each particles.

  property fluidFrictionCoef

    Fluid resolution: fitting coefficient for the fluid wall friction

  fluidResolution((HydroForceEngine)arg1, (float)arg2, (float)arg3) → None :

    Solve the 1D volume-averaged fluid momentum balance on the defined mesh (nCell, deltaZ) from the volume-averaged solid profiles (phiPart,:yref:vxPart<HydroForceEngine.vxPart>,:yref:averageDrag<HydroForceEngine.averageDrag>), which can be evaluated with the averageProfile function.

  property fluidWallFriction

    Fluid resolution: if set to true, introduce a sink term to account for the fluid friction at the wall, see [Maurin2015] for details. Requires to set the width of the channel. It might slow down significantly the calculation.

  property gravity

    Gravity vector

  property ids

    Ids list of bodies affected by this PartialEngine.

  property ilm

    Fluid resolution: type of mixing length resolution applied: 0: classical Prandtl mixing length, 1: Prandtl mixing length with free-surface effects, 2: Damp turbulence accounting for the presence of particles [Li1995], see [RevilBaudard2013] for more details.

  initialization((HydroForceEngine)arg1) → None :

    Initialize the necessary parameters to make HydroForceEngine run. Necessary to execute before any simulation run, otherwise it crashes

  property irheolf

    Fluid resolution: effective fluid viscosity option: 0: pure fluid viscosity, 1: Einstein viscosity.

  property iturbu

    Fluid resolution: activate the turbulence resolution, 1, or not, 0

  property iusl

    Fluid resolution: option to set the boundary condition at the top of the fluid, 0: Dirichlet, fixed (\(u=uTop\) en \(z=h\)), 1:Neumann, free-surface (\(du/dz=0\) en \(z=h\)).

  property kappa

    Fluid resolution: Von Karman constant. Can be tuned to account for the effect of particles on the fluid turbulence, see e.g. [RevilBaudard2015]

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property lift

    Option to activate or not the evaluation of the lift

  property lubrication

    Condition to activate the calculation of the lubrication force.

  property multiDragPart

    Spatial-averaged mean drag force for each class of particle. Un-used ? Or just for debug.

  property multiPhiPart

    Spatial-averaged solid volume fraction for each class of particle.

  property multiVxPart

    Spatial-averaged velocity in x direction for each class of particle.

  property multiVyPart

    Spatial-averaged velocity in y direction for each class of particle.

  property multiVzPart

    Spatial-averaged velocity in z direction for each class of particle.

  property nCell

    Number of cell in the depth

  property nbAverageT

    If >0, perform a time-averaging (in addition to the spatial averaging) over nbAverage steps.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property phiBed

    Turbulence modelling parameter. Associated with mixing length modelling ilm = 5.

  property phiMax

    Fluid resolution: maximum solid volume fraction.

  property phiPart

    Discretized solid volume fraction depth profile. Can be taken as input parameter or evaluated directly inside the engine, calling from python the averageProfile() function

  property phiPart1

    Discretized solid volume fraction depth profile of particles of type 1. Evaluated when twoSize is set to True.

  property phiPart2

    Discretized solid volume fraction depth profile of particles of type 2. Evaluated when twoSize is set to True.

  property pointParticleAverage

    Evaluate the averaged with a point particle method. If False, consider the particle extent and weigth the averaged by the volume contained in each averaging cell.

  property radiusPart

    Reference particle radius

  property radiusPart1

    Radius of the particles of type 1. Useful only when twoSize is set to True.

  property radiusPart2

    Radius of the particles of type 2. Useful only when twoSize is set to True.

  property radiusParts

    Variables containing the number of different radius of particles in the simulation. Allow to perform class averaging by particle size.

  property roughnessPartScale

    Roughness length scale of the particle. In practice, the lubrication force is cut off when the two particles are at a distance roughnessPartScale.

  property steadyFlow

    Condition to modify the buoyancy force according to the physical difference between a fluid at rest and a steady fluid flow. For more details see [Maurin2018]

  property taufsi

    Fluid Resolution: Create Taufsi/rhof = dragTerm/(rhof(vf-vxp)) to transmit to the fluid code

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  turbulentFluctuation((HydroForceEngine)arg1) → None :

    Apply a discrete random walk model to the evaluation of the drag force to account for the fluid velocity turbulent fluctuations. Very simple model applying fluctuations from the values of the Reynolds stresses in order to recover the property \(<u_x'u_z'> (z) = <R^f_{xz}>(z)/\rho^f\). The random fluctuations are modified over a time scale given by the eddy turn over time.

  turbulentFluctuationZDep((HydroForceEngine)arg1) → None :

    Apply turbulent fluctuation to the problem similarly to turbulentFluctuation but with an update of the fluctuation depending on the particle position.

  property turbulentViscosity

    Fluid Resolution: turbulent viscocity as a function of the depth

  property twoSize

    Not maintained anymore. Option to activate when considering two particle size in the simulation. When activated evaluate the average solid volume fraction and drag force for the two type of particles of diameter diameterPart1 and diameterPart2 independently.

  property uTop

    Fluid resolution: fluid velocity at the top boundary when iusl = 0

  property unCorrelatedFluctuations

    Condition to generate uncorrelated fluid fluctuations. Default case represent in free-surface flows, for which the vertical and streamwise fluid velocity fluctuations are correlated (see e.g. reference book of Nezu & Nagakawa 1992, turbulence in open channel flows).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vCell

    Volume of averaging cell

  property vFluctX

    Vector associating a streamwise fluid velocity fluctuation to each particle. Fluctuation calculated in the C++ code from the discrete random walk model

  property vFluctY

    Vector associating a spanwise fluid velocity fluctuation to each particle. Fluctuation calculated in the C++ code from the discrete random walk model

  property vFluctZ

    Vector associating a normal fluid velocity fluctuation to each particle. Fluctuation calculated in the C++ code from the discrete random walk model

  property vPart

    Discretized streamwise solid velocity depth profile, in x, y and z direction. Only the x direction measurement is taken into account in the 1D fluid coupling resolution. The two other can be used as output parameters. The x component can be taken as input parameter, or evaluated directly inside the engine, calling from python the averageProfile() function

  property velFluct

    If true, activate the determination of turbulent fluid velocity fluctuation for the next time step only at the position of each particle, using a simple discrete random walk (DRW) model based on the Reynolds stresses profile (ReynoldStresses)

  property viscoDyn

    Dynamic viscosity of the fluid, by default - viscosity of water

  property viscousSubLayer

    Fluid resolution: solve the viscous sublayer close to the bottom boundary if set to 1

  property vxFluid

    Discretized streamwise fluid velocity depth profile at t

  property vxPart

    Discretized streamwise solid velocity depth profile. Can be taken as input parameter, or evaluated directly inside the engine, calling from python the averageProfile() function

  property vxPart1

    Discretized solid streamwise velocity depth profile of particles of type 1. Evaluated when twoSize is set to True.

  property vxPart2

    Discretized solid streamwise velocity depth profile of particles of type 2. Evaluated when twoSize is set to True.

  property vyPart

    Discretized spanwise solid velocity depth profile. Can be taken as input parameter, or evaluated directly inside the engine, calling from python the averageProfile() function

  property vyPart1

    Discretized solid spanwise velocity depth profile of particles of type 1. Evaluated when twoSize is set to True.

  property vyPart2

    Discretized solid spanwise velocity depth profile of particles of type 2. Evaluated when twoSize is set to True.

  property vzPart

    Discretized wall-normal solid velocity depth profile. Can be taken as input parameter, or evaluated directly inside the engine, calling from python the averageProfile() function

  property vzPart1

    Discretized solid wall-normal velocity depth profile of particles of type 1. Evaluated when twoSize is set to True.

  property vzPart2

    Discretized solid wall-normal velocity depth profile of particles of type 2. Evaluated when twoSize is set to True.

  property wallFrictionModel

    Model used to compute the wall friction factor \(f\). 0: Blasius (1913) explicit formula \(f=0.3164/Re^{1/4}\) (faster), 1: Graf and Altinakar (1998) implicit formula \(f=(2\log_{10}(Re \sqrt{f_{old}} /4) + 0.32)^{-2}\).

  property zRef

    Position of the reference point which correspond to the first value of the fluid velocity, i.e. to the ground.

class yade.wrapper.InterpolatingDirectedForceEngine(inherits ForceEngine → PartialEngine → Engine → Serializable)

  Engine for applying force of varying magnitude but constant direction on subscribed bodies. times and magnitudes must have the same length, direction (normalized automatically) gives the orientation.

  As usual with interpolating engines: the first magnitude is used before the first time point, last magnitude is used after the last time point. Wrap specifies whether time wraps around the last time point to the first time point.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property direction

    Contact force direction (normalized automatically)

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property force

    Force to apply.

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property magnitudes

    Force magnitudes readings [N]

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property times

    Time readings [s]

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wrap

    wrap to the beginning of the sequence if beyond the last time point

class yade.wrapper.InterpolatingHelixEngine(inherits HelixEngine → RotationEngine → KinematicEngine → PartialEngine → Engine → Serializable)

  Engine applying spiral motion, finding current angular velocity by linearly interpolating in times and velocities and translation by using slope parameter.

  The interpolation assumes the margin value before the first time point and last value after the last time point. If wrap is specified, time will wrap around the last times value to the first one (note that no interpolation between last and first values is done).

  property angleTurned

    How much have we turned so far. (auto-updated) [rad]

  property angularVelocities

    List of angular velocities; manadatorily of same length as times. [rad/s]

  property angularVelocity

    Angular velocity. [rad/s]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property linearVelocity

    Linear velocity [m/s]

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property rotateAroundZero

    If True, bodies will not rotate around their centroids, but rather around `zeroPoint`.

  property rotationAxis

    Axis of rotation (direction); will be normalized automatically.

  property slope

    Axial translation per radian turn (can be negative) [m/rad]

  property times

    List of time points at which velocities are given; must be increasing [s]

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wrap

    Wrap t if t>times_n, i.e. t_wrapped=t-N*(times_n-times_0)

  property zeroPoint

    Point around which bodies will rotate if `rotateAroundZero` is True

class yade.wrapper.KinematicEngine(inherits PartialEngine → Engine → Serializable)

  Abstract engine for applying prescribed displacement.

  Note

  Derived classes should override the `apply` with given list of `ids` (not `action` with PartialEngine.ids), so that they work when combined together; velocity and angular velocity of all subscribed bodies is reset before the `apply` method is called, it should therefore only increment those quantities.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.LawTester(inherits PartialEngine → Engine → Serializable)

  Prescribe and apply deformations of an interaction in terms of local mutual displacements and rotations. The loading path is specified either using path (as sequence of 6-vectors containing generalized displacements \(u_x\), \(u_y\), \(u_z\), \(\phi_x\), \(\phi_y\), \(\phi_z\)) or disPath (\(u_x\), \(u_y\), \(u_z\)) and rotPath (\(\phi_x\), \(\phi_y\), \(\phi_z\)). Time function with time values (step numbers) corresponding to points on loading path is given by pathSteps. Loading values are linearly interpolated between given loading path points, and starting zero-value (the initial configuration) is assumed for both path and pathSteps. hooks can specify python code to run when respective point on the path is reached; when the path is finished, doneHook will be run.

  LawTester should be placed between InteractionLoop and NewtonIntegrator in the simulation loop, since it controls motion via setting linear/angular velocities on particles; those velocities are integrated by NewtonIntegrator to yield an actual position change, which in turn causes IGeom to be updated (and contact law applied) when InteractionLoop is executed. Constitutive law generating forces on particles will not affect prescribed particle motion, since both particles have all DoFs blocked when first used with LawTester.

  LawTester uses, as much as possible, IGeom to provide useful data (such as local coordinate system), but is able to compute those independently if absent in the respective IGeom:

  IGeom | #DoFs | LawTester support level
  --- | --- | ---
  L3Geom | 3 | full
  L6Geom | 6 | full
  ScGeom | 3 | emulate local coordinate system
  ScGeom6D | 6 | emulate local coordinate system

  Depending on IGeom, 3 (\(u_x\), \(u_y\), \(u_z\)) or 6 (\(u_x\), \(u_y\), \(u_z\), \(\phi_x\), \(\phi_y\), \(\phi_z\)) degrees of freedom (DoFs) are controlled with LawTester, by prescribing linear and angular velocities of both particles in contact. All DoFs controlled with LawTester are orthogonal (fully decoupled) and are controlled independently.

  When 3 DoFs are controlled, rotWeight controls whether local shear is applied by moving particle on arc around the other one, or by rotating without changing position; although such rotation induces mutual rotation on the interaction, it is ignored with IGeom with only 3 DoFs. When 6 DoFs are controlled, only arc-displacement is applied for shear, since otherwise mutual rotation would occur.

  idWeight distributes prescribed motion between both particles (resulting local deformation is the same if `id1` is moved towards `id2` or `id2` towards `id1`). This is true only for \(u_x\), \(u_y\), \(u_z\), \(\phi_x\) however ; bending rotations \(\phi_y\), \(\phi_z\) are nevertheless always distributed regardless of `idWeight` to both spheres in inverse proportion to their radii, so that there is no shear induced.

  LawTester knows current contact deformation from 2 sources: from its own internal data (which are used for prescribing the displacement at every step), which can be accessed in uTest, and from IGeom itself (depending on which data it provides), which is stored in uGeom. These two values should be identical (disregarding numerical percision), and it is a way to test whether IGeom and related functors compute what they are supposed to compute.

  LawTester-operated interactions can be rendered with GlExtra_LawTester renderer.

  See scripts/test/law-test.py for an example.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property disPath

    Loading path, where each Vector3 contains desired normal displacement and two components of the shear displacement (in local coordinate system, which is being tracked automatically. If shorter than rotPath, the last value is repeated.

  property displIsRel

    Whether displacement values in disPath are normalized by reference contact length (r1+r2 for 2 spheres).

  property doneHook

    Python command (as string) to run when end of the path is achieved. If empty, the engine will be set dead.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property hooks

    Python commands to be run when the corresponding point in path is reached, before doing other things in that particular step. See also doneHook.

  property idWeight

    Float, usually ∈〈0,1〉, determining on how are displacements distributed between particles (0 for id1, 1 for id2); intermediate values will apply respective part to each of them. This parameter is ignored with 6-DoFs IGeom.

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property pathSteps

    Step number for corresponding values in path; if shorter than path, distance between last 2 values is used for the rest.

  property refLength

    Reference contact length, for rendering only.

  property renderLength

    Characteristic length for the purposes of rendering, set equal to the smaller radius.

  property rotPath

    Rotational components of the loading path, where each item contains torsion and two bending rotations in local coordinates. If shorter than path, the last value is repeated.

  property rotWeight

    Float ∈〈0,1〉 determining whether shear displacement is applied as rotation or displacement on arc (0 is displacement-only, 1 is rotation-only). Not effective when mutual rotation is specified.

  property step

    Step number in which this engine is active; determines position in path, using pathSteps.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property trsf

    Transformation matrix for the local coordinate system. (auto-updated)

  property uGeom

    Current generalized displacements (3 displacements, 3 rotations), as stored in the interation itself. They should corredpond to uTest, otherwise a bug is indicated.

  property uTest

    Current generalized displacements (3 displacements, 3 rotations), as they should be according to this LawTester. Should correspond to uGeom.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property uuPrev

    Generalized displacement values reached in the previous step, for knowing which increment to apply in the current step.

class yade.wrapper.LinearDragEngine(inherits PartialEngine → Engine → Serializable)

  Apply viscous resistance or linear drag on some particles at each step, decelerating them proportionally to their linear velocities. The applied force reads

  \[F_{d}=-b{\vec{v}}\]

  where \(b\) is the linear drag, \(\vec{v}\) is particle’s velocity.

  \[b=6\pi\nu r \]

  where \(\nu\) is the medium viscosity, \(r\) is the Stokes radius of the particle (but in this case we accept it equal to sphere radius for simplification),

  Note

  linear drag is only applied to spherical particles, listed in ids.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property nu

    Viscosity of the medium.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.RadialForceEngine(inherits PartialEngine → Engine → Serializable)

  Apply force of given magnitude directed away from spatial axis.

  property axisDir

    Axis direction (normalized automatically)

  property axisPt

    Point on axis

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property fNorm

    Applied force magnitude

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.RotationEngine(inherits KinematicEngine → PartialEngine → Engine → Serializable)

  Engine applying rotation (by setting angular velocity) to subscribed bodies. If rotateAroundZero is set, then each body is also displaced around zeroPoint.

  property angularVelocity

    Angular velocity. [rad/s]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property rotateAroundZero

    If True, bodies will not rotate around their centroids, but rather around `zeroPoint`.

  property rotationAxis

    Axis of rotation (direction); will be normalized automatically.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property zeroPoint

    Point around which bodies will rotate if `rotateAroundZero` is True

class yade.wrapper.ServoPIDController(inherits TranslationEngine → KinematicEngine → PartialEngine → Engine → Serializable)

  PIDController servo-engine for applying prescribed force on bodies. http://en.wikipedia.org/wiki/PID_controller

  property axis

    Unit vector along which apply the velocity [-]

  property curVel

    Current applied velocity [m/s]

  property current

    Current value for the controller [N]

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property errorCur

    Current error [N]

  property errorPrev

    Previous error [N]

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property iTerm

    Integral term [N]

  property ids

    Ids list of bodies affected by this PartialEngine.

  property iterPeriod

    Periodicity criterion of velocity correlation [-]

  property iterPrevStart

    Previous iteration of velocity correlation [-]

  property kD

    Derivative gain/coefficient for the PID-controller [-]

  property kI

    Integral gain/coefficient for the PID-controller [-]

  property kP

    Proportional gain/coefficient for the PID-controller [-]

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property maxVelocity

    Velocity [m/s]

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property target

    Target value for the controller [N]

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property translationAxis

    Direction of imposed translation [Vector3]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property velocity

    Scalar value of the imposed velocity [m/s]. Imposed vector velocity is velocity * axis

class yade.wrapper.StepDisplacer(inherits PartialEngine → Engine → Serializable)

  Apply generalized displacement (displacement or rotation) stepwise on subscribed bodies. Could be used for purposes of contact law tests (by moving one sphere compared to another), but in this case, see rather LawTester

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property mov

    Linear displacement step to be applied per iteration, by addition to State.pos.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property rot

    Rotation step to be applied per iteration (via rotation composition with State.ori).

  property setVelocities

    If false, positions and orientations are directly updated, without changing the speeds of concerned bodies. If true, only velocity and angularVelocity are modified. In this second case integrator is supposed to be used, so that, thanks to this Engine, the bodies will have the prescribed jump over one iteration (dt).

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.TimeAverager(inherits PartialEngine → Engine → Serializable)

  Average data over time for specific sphere identified by ids. Data are position, velocity, angular velocity, global resultant force and torque, resultant force and torque computed from contacts only and contact force field (see description below). The data must be first initialized with its instantaneous value by running the initialization method. Then averaged values are updated at every time steps with a moving average algorythm, until the initialization method is run again.

  property computeContactForceField

    Wether to compute and average contact force field at the surface of the particles (experimental feature). The contact force field is obtained by ditributing the contact forces on a grid at the surface of the sphere. The contact forces are spread on each point of the grid, according to the distance between the contact point and the grid point. The algorythm uses a gaussian kernel to smooth the field. If computeContactForceField is true, grid and sigma parameters must be filled in. This can significantly increase the computation time for dense grid or high number of particles.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  getAngVel((TimeAverager)arg1, (int)arg2) → yade._minieigenHP.Vector3 :

    Get averaged angular velocity of particle since last initialization

  getContactForce((TimeAverager)arg1, (int)arg2) → yade._minieigenHP.Vector3 :

    Get averaged resultant force computed from contact forces on particle since last initialization

  getContactForceField((TimeAverager)arg1, (int)arg2) → object :

    Get averaged contact force field at the surface of the particle since last initialization

  getContactTorque((TimeAverager)arg1, (int)arg2) → yade._minieigenHP.Vector3 :

    Get averaged resultant torque computed from contact forces on particle since last initialization

  getForce((TimeAverager)arg1, (int)arg2) → yade._minieigenHP.Vector3 :

    Get averaged resultant force of particle since last initialization

  getNbContact((TimeAverager)arg1, (int)arg2) → float :

    Get averaged number of contact points on particle since last initialization

  getPos((TimeAverager)arg1, (int)arg2) → yade._minieigenHP.Vector3 :

    Get averaged position of particle since last initialization

  getTorque((TimeAverager)arg1, (int)arg2) → yade._minieigenHP.Vector3 :

    Get averaged resultant torque of particle since last initialization

  getVel((TimeAverager)arg1, (int)arg2) → yade._minieigenHP.Vector3 :

    Get averaged velocity of particle since last initialization

  property grid

    Grid on which to compute the contact force field. Should be a list of 3D coordinates at the surface of the particle (a simple way to generate a well distributed grid at the surface of a sphere is with the Fibonacci lattice method).

  property ids

    Ids list of bodies affected by this PartialEngine.

  initialization((TimeAverager)arg1) → None :

    Initialize tAccu to zero and the averaged variables to there instantaneous values. Necessary to execute before any simulation run, otherwise it crashes.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property sigma

    Standard deviation of the Gaussian function, which determines how the contact forces are weighted based on their distance from a contact point. It is usually set at the order of the distance between two points in the grid.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.TorqueEngine(inherits PartialEngine → Engine → Serializable)

  Apply given torque (momentum) value at every subscribed particle, at every step.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property moment

    Torque value to be applied.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.TranslationEngine(inherits KinematicEngine → PartialEngine → Engine → Serializable)

  Engine applying translation motion (by setting linear velocity) to subscribed bodies.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property ids

    Ids list of bodies affected by this PartialEngine.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  property translationAxis

    Direction of imposed translation [Vector3]

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property velocity

    Scalar value of the imposed velocity [m/s]. Imposed vector velocity is velocity * axis

## Dispatchers

Inheritance graph of Dispatcher, gray dashed classes are discussed in their own sections: LawDispatcher, IGeomDispatcher, BoundDispatcher, IPhysDispatcher, InternalForceDispatcher.

class yade.wrapper.Dispatcher(inherits Engine → Serializable)

  Engine dispatching control to its associated functors, based on types of argument it receives. This abstract base class provides no functionality in itself.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GlBoundDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((GlBoundDispatcher)arg1, (Bound)arg2) → GlBoundFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((GlBoundDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GlIGeomDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((GlIGeomDispatcher)arg1, (IGeom)arg2) → GlIGeomFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((GlIGeomDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GlIPhysDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((GlIPhysDispatcher)arg1, (IPhys)arg2) → GlIPhysFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((GlIPhysDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GlShapeDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((GlShapeDispatcher)arg1, (Shape)arg2) → GlShapeFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((GlShapeDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GlStateDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((GlStateDispatcher)arg1, (State)arg2) → GlStateFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((GlStateDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

## Functors

Inheritance graph of Functor, gray dashed classes are discussed in their own sections: GlShapeFunctor, GlBoundFunctor, IPhysFunctor, GlIGeomFunctor, IGeomFunctor, GlIPhysFunctor, BoundFunctor, GlStateFunctor, InternalForceFunctor, LawFunctor.

class yade.wrapper.Functor(inherits Serializable)

  Function-like object that is called by Dispatcher, if types of arguments match those the Functor declares to accept.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

## Bounding volume creation

### BoundFunctor

Inheritance graph of BoundFunctor.

class yade.wrapper.BoundFunctor(inherits Functor → Serializable)

  Functor for creating/updating Body::bound.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_Box_Aabb(inherits BoundFunctor → Functor → Serializable)

  Create/update an Aabb of a Box.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_ChainedCylinder_Aabb(inherits BoundFunctor → Functor → Serializable)

  Functor creating Aabb from ChainedCylinder.

  property aabbEnlargeFactor

    Relative enlargement of the bounding box; deactivated if negative.

    Note

    This attribute is used to create distant interaction, but is only meaningful with an IGeomFunctor which will not simply discard such interactions: Ig2_Cylinder_Cylinder_ScGeom::interactionDetectionFactor should have the same value as aabbEnlargeFactor.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_Cylinder_Aabb(inherits BoundFunctor → Functor → Serializable)

  Functor creating Aabb from Cylinder.

  property aabbEnlargeFactor

    Relative enlargement of the bounding box; deactivated if negative.

    Note

    This attribute is used to create distant interaction, but is only meaningful with an IGeomFunctor which will not simply discard such interactions: Ig2_Cylinder_Cylinder_ScGeom::interactionDetectionFactor should have the same value as aabbEnlargeFactor.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_DeformableElement_Aabb(inherits BoundFunctor → Functor → Serializable)

  Functor creating Aabb from DeformableElement.

  property aabbEnlargeFactor

    Relative enlargement of the bounding box; deactivated if negative.

    Note

    This attribute is used to create distant interaction, but is only meaningful with an IGeomFunctor which will not simply discard such interactions: Ig2_Sphere_Sphere_ScGeom::interactionDetectionFactor should have the same value as aabbEnlargeFactor.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_Facet_Aabb(inherits BoundFunctor → Functor → Serializable)

  Creates/updates an Aabb of a Facet.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_FluidDomainBbox_Aabb(inherits BoundFunctor → Functor → Serializable)

  creates/updates an Aabb of a FluidDomainBbox.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_GridConnection_Aabb(inherits BoundFunctor → Functor → Serializable)

  Functor creating Aabb from a GridConnection.

  property aabbEnlargeFactor

    Relative enlargement of the bounding box; deactivated if negative.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_LevelSet_Aabb(inherits BoundFunctor → Functor → Serializable)

  Creates/updates an Aabb of a LevelSet

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_Node_Aabb(inherits BoundFunctor → Functor → Serializable)

  Functor creating Aabb from Node.

  property aabbEnlargeFactor

    Relative enlargement of the bounding box; deactivated if negative.

    Note

    This attribute is used to create distant interaction, but is only meaningful with an IGeomFunctor which will not simply discard such interactions: Ig2_Sphere_Sphere_ScGeom::interactionDetectionFactor should have the same value as aabbEnlargeFactor.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_PFacet_Aabb(inherits BoundFunctor → Functor → Serializable)

  Functor creating Aabb from a PFacet.

  property aabbEnlargeFactor

    Relative enlargement of the bounding box; deactivated if negative.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_Sphere_Aabb(inherits BoundFunctor → Functor → Serializable)

  Functor creating Aabb from Sphere.

  property aabbEnlargeFactor

    Relative enlargement of the bounding box; deactivated if negative.

    Note

    This attribute is used to create distant interaction, but is only meaningful with an IGeomFunctor which will not simply discard such interactions: Ig2_Sphere_Sphere_ScGeom::interactionDetectionFactor should have the same value as aabbEnlargeFactor.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_Subdomain_Aabb(inherits BoundFunctor → Functor → Serializable)

  Creates/updates an Aabb of a Subdomain (mpi parallel simulations).

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_Tetra_Aabb(inherits BoundFunctor → Functor → Serializable)

  Create/update Aabb of a Tetra

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Bo1_Wall_Aabb(inherits BoundFunctor → Functor → Serializable)

  Creates/updates an Aabb of a Wall

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.PotentialParticle2AABB(inherits BoundFunctor → Functor → Serializable)

  EXPERIMENTAL. Functor creating Aabb from PotentialParticle.

  property aabbEnlargeFactor

    see Sphere2AABB.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### BoundDispatcher

class yade.wrapper.BoundDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property activated

    Whether the engine is activated (only should be changed by the collider)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((BoundDispatcher)arg1, (Shape)arg2) → BoundFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((BoundDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property minSweepDistFactor

    Minimal distance by which enlarge all bounding boxes; superseeds computed value of sweepDist when lower that (minSweepDistFactor x sweepDist). Updated by the collider. (auto-updated).

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property sweepDist

    Distance by which enlarge all bounding boxes, to prevent collider from being run at every step (only should be changed by the collider).

  property targetInterv

    see InsertionSortCollider::targetInterv (auto-updated)

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updatingDispFactor

    see InsertionSortCollider::updatingDispFactor (auto-updated)

## Interaction Geometry creation

### IGeomFunctor

Inheritance graph of IGeomFunctor.

class yade.wrapper.IGeomFunctor(inherits Functor → Serializable)

  Functor for creating/updating Interaction::geom objects.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Box_LevelSet_ScGeom(inherits IGeomFunctor → Functor → Serializable)

  Creates or updates a ScGeom instance representing the intersection of one LevelSet body with one Box body. Normal is given by the box geometry while overlap and contact points are defined likewise to Ig2_LevelSet_LevelSet_ScGeom. Restricted to the case of Boxes for which local and global axes coincide, and with non zero thickness, and assuming the center of the level set body never enters into the box (ie excluding big overlaps). You may prefer using Ig2_Wall_LevelSet_ScGeom.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Box_Sphere_ScGeom(inherits IGeomFunctor → Functor → Serializable)

  Create an interaction geometry ScGeom from Box and Sphere, representing the box with a projected virtual sphere of same radius.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property hertzian

    If True, the equivalent radius for the Box (ScGeom.refR1) is chosen as 1e8 times the Sphere’s radius (closer to Hertzian theory, where it is infinite). Both are equal if False

  property interactionDetectionFactor

    Enlarge sphere radii by this factor (if >1), to permit creation of distant interactions.

    InteractionGeometry will be computed when interactionDetectionFactor*(rad) > distance.

    Note

    This parameter is functionally coupled with Bo1_Sphere_Aabb::aabbEnlargeFactor, which will create larger bounding boxes and should be of the same value.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Box_Sphere_ScGeom6D(inherits Ig2_Box_Sphere_ScGeom → IGeomFunctor → Functor → Serializable)

  Create an interaction geometry ScGeom6D from Box and Sphere, representing the box with a projected virtual sphere of same radius.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property hertzian

    If True, the equivalent radius for the Box (ScGeom.refR1) is chosen as 1e8 times the Sphere’s radius (closer to Hertzian theory, where it is infinite). Both are equal if False

  property interactionDetectionFactor

    Enlarge sphere radii by this factor (if >1), to permit creation of distant interactions.

    InteractionGeometry will be computed when interactionDetectionFactor*(rad) > distance.

    Note

    This parameter is functionally coupled with Bo1_Sphere_Aabb::aabbEnlargeFactor, which will create larger bounding boxes and should be of the same value.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_ChainedCylinder_ChainedCylinder_ScGeom6D(inherits IGeomFunctor → Functor → Serializable)

  Create/update a ScGeom instance representing connexion between chained cylinders.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property halfLengthContacts

    If True, Cylinders nodes interact like spheres of radius 0.5*length, else one node has size length while the other has size 0. The difference is mainly the locus of rotation definition.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Facet_Sphere_L3Geom(inherits Ig2_Sphere_Sphere_L3Geom → IGeomFunctor → Functor → Serializable)

  Incrementally compute L3Geom for contact between Facet and Sphere. Uses attributes of Ig2_Sphere_Sphere_L3Geom.

  property approxMask

    Selectively enable geometrical approximations (bitmask); add the values for approximations to be enabled.

    1 | use previous transformation to transform velocities (which are known at mid-steps), instead of mid-step transformation computed as quaternion slerp at t=0.5.
    2 | do not take average (mid-step) normal when computing relative shear displacement, use previous value instead
    4 | do not re-normalize average (mid-step) normal, if used.…

    By default, the mask is zero, wherefore none of these approximations is used.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property distFactor

    Create interaction if spheres are not futher than distFactor *(r1+r2). If negative, zero normal deformation will be set to be the initial value (otherwise, the geometrical distance is the ‘’zero’’ one).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property noRatch

    See Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property trsfRenorm

    How often to renormalize trsf; if non-positive, never renormalized (simulation might be unstable)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Facet_Sphere_ScGeom(inherits IGeomFunctor → Functor → Serializable)

  Create/update a ScGeom instance representing intersection of Facet and Sphere. Denoting \(u_n\) the corresponding overlap, \(\vec{C}\) the contact point and \(\vec{n}\) the contact normal while \(\vec{S}\) stands for sphere’s center, \(\vec{H}\) for its projection into the facet plane, and \(R\) for the sphere’s radius, we have:

  - \(u_n = R - ||\vec{HS}||\)

  - \(\vec{n} = \dfrac{\vec{HS}}{||\vec{HS}||}\)

  when \(\vec{H}\) strictly belongs to the Facet surface (different expressions otherwise) and

  - \(\vec{C} = \vec{S} - (||\vec{HS}||-u_n/2)\vec{n}\)

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property hertzian

    If True, the equivalent radius for the Facet (ScGeom.refR1) is chosen as 1e8 times the Sphere’s radius (closer to Hertzian therory, where it is infinite). Otherwise, it is chosen to be equal to twice the Sphere’s radius.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property shrinkFactor

    The radius of the inscribed circle of the facet is decreased by the value of the sphere’s radius multiplied by shrinkFactor. From the definition of contact point on the surface made of facets, the given surface is not continuous and becomes in effect surface covered with triangular tiles, with gap between the separate tiles equal to the sphere’s radius multiplied by 2×*shrinkFactor*. If zero, no shrinking is done.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Facet_Sphere_ScGeom6D(inherits Ig2_Facet_Sphere_ScGeom → IGeomFunctor → Functor → Serializable)

  Create an interaction geometry ScGeom6D from Facet and Sphere, representing the Facet with a projected virtual sphere of same radius.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property hertzian

    If True, the equivalent radius for the Facet (ScGeom.refR1) is chosen as 1e8 times the Sphere’s radius (closer to Hertzian therory, where it is infinite). Otherwise, it is chosen to be equal to twice the Sphere’s radius.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property shrinkFactor

    The radius of the inscribed circle of the facet is decreased by the value of the sphere’s radius multiplied by shrinkFactor. From the definition of contact point on the surface made of facets, the given surface is not continuous and becomes in effect surface covered with triangular tiles, with gap between the separate tiles equal to the sphere’s radius multiplied by 2×*shrinkFactor*. If zero, no shrinking is done.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_GridConnection_GridConnection_GridCoGridCoGeom(inherits IGeomFunctor → Functor → Serializable)

  Create/update a GridCoGridCoGeom instance representing the geometry of a contact point between two GridConnection , including relative rotations.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_GridConnection_PFacet_ScGeom(inherits Ig2_Sphere_GridConnection_ScGridCoGeom → IGeomFunctor → Functor → Serializable)

  Create/update a ScGeom instance representing intersection of Facet and GridConnection.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property shrinkFactor

    The radius of the inscribed circle of the facet is decreased by the value of the sphere’s radius multipled by shrinkFactor. From the definition of contact point on the surface made of facets, the given surface is not continuous and becomes in effect surface covered with triangular tiles, with gap between the separate tiles equal to the sphere’s radius multiplied by 2×*shrinkFactor*. If zero, no shrinking is done.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_GridNode_GridNode_GridNodeGeom6D(inherits Ig2_Sphere_Sphere_ScGeom → IGeomFunctor → Functor → Serializable)

  Create/update a GridNodeGeom6D instance representing the geometry of a contact point between two GridNode, including relative rotations.

  property avoidGranularRatcheting

    Define relative velocity so that ratcheting is avoided. It applies for sphere-sphere contacts. It eventualy also apply for sphere-emulating interactions (i.e. convertible into the ScGeom type), if the virtual sphere’s motion is defined correctly (see e.g. Ig2_Sphere_ChainedCylinder_CylScGeom).

    Short explanation of what we want to avoid :

    Numerical ratcheting is best understood considering a small elastic cycle at a contact between two grains : assuming b1 is fixed, impose this displacement to b2 :

    1. translation dx in the normal direction

    2. rotation a

    3. translation -dx (back to the initial position)

    4. rotation -a (back to the initial orientation)

    If the branch vector used to define the relative shear in rotation×branch is not constant (typically if it is defined from the vector center→contactPoint), then the shear displacement at the end of this cycle is not zero: rotations a and -a are multiplied by branches of different lengths.

    It results in a finite contact force at the end of the cycle even though the positions and orientations are unchanged, in total contradiction with the elastic nature of the problem. It could also be seen as an inconsistent energy creation or loss. Given that DEM simulations tend to generate oscillations around equilibrium (damped mass-spring), it can have a significant impact on the evolution of the packings, resulting for instance in slow creep in iterations under constant load.

    The solution adopted here to avoid ratcheting is as proposed by McNamara and co-workers. They analyzed the ratcheting problem in detail - even though they comment on the basis of a cycle that differs from the one shown above. One will find interesting discussions in e.g. [McNamara2008], even though solution it suggests is not fully applied here (equations of motion are not incorporating alpha, in contradiction with what is suggested by McNamara et al.).

  property bases

    Ordered list of types (as strings) this functor accepts.

  property creep

    Substract rotational creep from relative rotation. The rotational creep ScGeom6D::twistCreep is a quaternion and has to be updated inside a constitutive law, see for instance Law2_ScGeom6D_CohFrictPhys_CohesionMoment.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

    InteractionGeometry will be computed when interactionDetectionFactor*(rad1+rad2) > distance.

    Note

    This parameter is functionally coupled with Bo1_Sphere_Aabb::aabbEnlargeFactor, which will create larger bounding boxes and should be of the same value.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updateRotations

    Precompute relative rotations. Turning this false can speed up simulations when rotations are not needed in constitutive laws (e.g. when spheres are compressed without cohesion and moment in early stage of a triaxial test), but is not foolproof. Change this value only if you know what you are doing.

class yade.wrapper.Ig2_LevelSet_LevelSet_LSnodeGeom(inherits Ig2_LevelSet_LevelSet_ScGeom → IGeomFunctor → Functor → Serializable)

  Same as Ig2_LevelSet_LevelSet_ScGeom except for the additional information in LSnodeGeom which should enable faster simulations, provided that Law2_ScGeom_FrictPhys_CundallStrack.neverErase is defined as True. This functor actually creates an interaction geom, enabling the interaction to turn real, as soon as a closest node can be detected (even though there is not yet mechanical contact). On the contrary, in order to avoid a continuous increase in the interaction list, it will take the responsibility to ask for interaction removal as soon as node treatment is impossible (due to an excessive gap), even when the interaction was previously real (at variance with general YADE design), prompting the need for setting InteractionLoop.warnRoleIg2 = False to avoid unnecessary warning messages in such cases, see examples/levelSet/lsNodeGeom.py for an example. Please also note that using this Functor is expected to bias (increase) unbalancedForce measurements as it artificially increases the number of real interactions, with a number of those carrying no force, making for a smaller mean average interaction force, hence a higher unbalanced force

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  normalMismatch((Ig2_LevelSet_LevelSet_ScGeom)arg1, (Interaction)cont) → float :

    Normal orientation mismatch (in radians) of given interaction cont if master and slave particles were to be exchanged. Does not support periodic boundary conditions at the moment.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_LevelSet_LevelSet_MultiScGeom(inherits Ig2_LevelSet_LevelSet_ScGeom → IGeomFunctor → Functor → Serializable)

  Multiple contact points version of Ig2_LevelSet_LevelSet_ScGeom for a MultiScGeom description of a contact between two (non-convex typically) LevelSet-shaped bodies (with a ScGeom interaction at each contacting surface node). Does not support periodic boundary conditions at the moment. It is designed to be used in combination with MultiFrictPhys for what concerns the interaction physics (which is here also created by that Ig2 in some contrast with general YADE design, from a developer point of view) [Duriez2023].

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  normalMismatch((Ig2_LevelSet_LevelSet_ScGeom)arg1, (Interaction)cont) → float :

    Normal orientation mismatch (in radians) of given interaction cont if master and slave particles were to be exchanged. Does not support periodic boundary conditions at the moment.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_LevelSet_LevelSet_ScGeom(inherits IGeomFunctor → Functor → Serializable)

  Creates or updates a ScGeom instance representing the contact of two convex LevelSet-shaped bodies after executing a master-slave algorithm that combines distance function \(\phi\) (LevelSet.distField) with surface nodes \(\vec{N}\) (LevelSet.surfNodes) [Duriez2021a] [Duriez2021b]. Denoting \(S\), resp. \(B\), the smallest, resp. biggest, contacting body, \(\vec{N_c}\) the surface node of \(S\) with the greatest penetration depth into \(B\) (its current position), \(u_n\) the corresponding overlap, \(\vec{C}\) the contact point and \(\vec{n}\) the contact normal, we have:

  - \(u_n = - \phi_B(\vec{N_c})\)

  - \(\vec{n} = \pm \vec{\nabla} \phi_S(\vec{N_c})\) chosen to be oriented from 1 to 2

  - \(\vec{C} = \vec{N_c} - \dfrac{u_n}{2} \vec{n}\)

  Note

  in case the two LevelSet grids no longer overlap for a previously existing interaction, the above workflow does not apply and \(u_n\) is assigned an infinite tensile value that should insure interaction removal in the same DEM iteration (for sure with Law2_ScGeom_FrictPhys_CundallStrack).

  While Ig2_LevelSet_LevelSet_MultiScGeom accomodates non-convex cases, Ig2_LevelSet_LevelSet_LSnodeGeom might be a better choice, towards faster simulations, when handling convex bodies.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  normalMismatch((Ig2_LevelSet_LevelSet_ScGeom)arg1, (Interaction)cont) → float :

    Normal orientation mismatch (in radians) of given interaction cont if master and slave particles were to be exchanged. Does not support periodic boundary conditions at the moment.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_LevelSet_LevelSet_VolumeGeom(inherits IGeomFunctor → Functor → Serializable)

  Creates or updates a VolumeGeom instance representing the contact of two LevelSet bodies of arbitrary shape. An algorithm is used that recursively evaluates the signed distance function \(\phi\) (LevelSet.distField) at increasingly finer mesh sizes to compute the overlap volume \(V\). Surface nodes are obsolete if this functor is used. Denoting \(u_n\) as the overlap, \(\vec{C}\) the contact point and \(\vec{n}\) the contact normal, we have:

  - \(u_n = V_n = \sum_i V_i(\vec{x}_i)\)

  - \(\vec{n} = \frac{ \sum_i V_i \vec{\nabla} \phi_1(\vec{x_i}) - \sum_i V_i \vec{\nabla} \phi_2(\vec{x_i}) }{2V_n}\) chosen to be oriented from 1 to 2

  - \(\vec{C} = \frac{1}{V_n} \sum_i \vec{x}_i * V_i(\vec{x}_i)\)

  Note

  Because this functor expresses the particle overlap \(u_n\) as a volume, care needs to be taken that only volume-based contact laws are used. Current contact laws in YADE mainly use the overlap distance to determine the force.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property nRefineOctree

    The number of refinements performed by the Octree algorithm used to compute the overlap volume between two particles. Default is 5. Note: (nr of layers, effective nr of integration elements): (1,1), (2,8), (3,64), (4,512), (5,4096), (n,8^(n-1)).

  property smearCoeffOctree

    Smearing coefficient for the smeared Heaviside step function in the overlap volume integration. The transition width, or smearing width, is equal to half the diagonal of the smallest integration cell divided by the smearing coefficient.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property useAABE

    If true, use the provided (locally) axis-aligned bounding ellipsoid (AABE) to reduce the potential overlap volume between the particles. Increases accuracy of the Octree algrithm because the smallest integration cells will be smaller.

class yade.wrapper.Ig2_PFacet_PFacet_ScGeom(inherits Ig2_Sphere_PFacet_ScGridCoGeom → Ig2_Sphere_GridConnection_ScGridCoGeom → IGeomFunctor → Functor → Serializable)

  Create/update a ScGridCoGeom instance representing intersection of Facet and Sphere.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property shrinkFactor

    The radius of the inscribed circle of the facet is decreased by the value of the sphere’s radius multipled by shrinkFactor. From the definition of contact point on the surface made of facets, the given surface is not continuous and becomes in effect surface covered with triangular tiles, with gap between the separate tiles equal to the sphere’s radius multiplied by 2×*shrinkFactor*. If zero, no shrinking is done.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_PP_PP_ScGeom(inherits IGeomFunctor → Functor → Serializable)

  EXPERIMENTAL. IGeom functor for PotentialParticle - PotentialParticle pair

  property accuracyTol

    accuracy desired, tolerance criteria for SOCP

  property areaStep

    Angular step (degrees) to calculate KnKsPhys.contactArea. Must be a divisor of 360, e.g. 1,2,3,4,5,6,8,9 and so on, to form a closed loop. Must be smaller than 90 degrees. Smaller angles lead to more accurate calculations but are more expensive

  property bases

    Ordered list of types (as strings) this functor accepts.

  property calContactArea

    Whether to calculate jointLength for 2-D contacts and contactArea for 2-D and 3-D contacts

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property twoDdir

    Direction of 2D

  property twoDimension

    Whether the contact is 2-D

  property unitWidth2D

    Unit width in 2D

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Sphere_ChainedCylinder_CylScGeom(inherits IGeomFunctor → Functor → Serializable)

  Create/update a ScGeom instance representing intersection of two Spheres.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Sphere_ChainedCylinder_CylScGeom6D(inherits Ig2_Sphere_ChainedCylinder_CylScGeom → IGeomFunctor → Functor → Serializable)

  Create/update a ScGeom6D instance representing the geometry of a contact point between two Spheres, including relative rotations.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property creep

    Substract rotational creep from relative rotation. The rotational creep ScGeom6D::twistCreep is a quaternion and has to be updated inside a constitutive law, see for instance Law2_ScGeom6D_CohFrictPhys_CohesionMoment.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updateRotations

    Precompute relative rotations. Turning this false can speed up simulations when rotations are not needed in constitutive laws (e.g. when spheres are compressed without cohesion and moment in early stage of a triaxial test), but is not foolproof. Change this value only if you know what you are doing.

class yade.wrapper.Ig2_Sphere_GridConnection_ScGridCoGeom(inherits IGeomFunctor → Functor → Serializable)

  Create/update a ScGridCoGeom6D instance representing the geometry of a contact point between a GricConnection and a Sphere including relative rotations.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Sphere_LevelSet_ScGeom(inherits IGeomFunctor → Functor → Serializable)

  Creates or updates a ScGeom instance representing the intersection of one LevelSet-shaped body with one Sphere-shaped body, where overlap is always chosen to occur inside the level set body (i.e. spheres will always be expelled). Contact normal \(\vec{n}\) is given by the level set normal at the centre of the sphere \(\vec{c}\) while overlap is given by \(R - \varphi\) with \(R\) the radius and \(\varphi\) the level set value. And contact points is defined as \(\vec{c}-\varphi \vec{n}\). This functionality does not require the level set to have surface nodes. Approximations for \(\phi\) outside the level set may become inaccurate if the spheres are of similar size or larger than the level set body. Accuracy is guaranteed it the largest sphere is around the same size, or smaller than, the smallest grid cell in the level set.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Sphere_PFacet_ScGridCoGeom(inherits Ig2_Sphere_GridConnection_ScGridCoGeom → IGeomFunctor → Functor → Serializable)

  Create/update a ScGridCoGeom instance representing intersection of PFacet and Sphere.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property shrinkFactor

    The radius of the inscribed circle of the facet is decreased by the value of the sphere’s radius multipled by shrinkFactor. From the definition of contact point on the surface made of facets, the given surface is not continuous and becomes in effect surface covered with triangular tiles, with gap between the separate tiles equal to the sphere’s radius multiplied by 2×*shrinkFactor*. If zero, no shrinking is done.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Sphere_Sphere_L3Geom(inherits IGeomFunctor → Functor → Serializable)

  Functor for computing incrementally configuration of 2 Spheres stored in L3Geom; the configuration is positioned in global space by local origin \(\vec{c}\) (contact point) and rotation matrix \(\mat{T}\) (orthonormal transformation matrix), and its degrees of freedom are local displacement \(\vec{u}\) (in one normal and two shear directions); with Ig2_Sphere_Sphere_L6Geom and L6Geom, there is additionally \(\vec{\phi}\). The first row of \(\mat{T}\), i.e. local \(x\)-axis, is the contact normal noted \(\vec{n}\) for brevity. Additionally, quasi-constant values of \(\vec{u}_0\) (and \(\vec{\phi}_0\)) are stored as shifted origins of \(\vec{u}\) (and \(\vec{\phi}\)); therefore, current value of displacement is always \(\curr{\vec{u}}-\vec{u}_0\).

  Suppose two spheres with radii \(r_i\), positions \(\vec{x}_i\), velocities \(\vec{v}_i\), angular velocities \(\vec{\omega}_i\).

  When there is not yet contact, it will be created if \(u_N=|\curr{\vec{x}}_2-\curr{\vec{x}}_1|-|f_d|(r_1+r2)<0\), where \(f_d\) is distFactor (sometimes also called ``interaction radius’’). If \(f_d>0\), then \(\vec{u}_{0x}\) will be initalized to \(u_N\), otherwise to 0. In another words, contact will be created if spheres enlarged by \(|f_d|\) touch, and the ``equilibrium distance’’ (where \(\vec{u}_x-\vec{u}-{0x}\) is zero) will be set to the current distance if \(f_d\) is positive, and to the geometrically-touching distance if negative.

  Local axes (rows of \(\mat{T}\)) are initially defined as follows:

  - local \(x\)-axis is \(\vec{n}=\vec{x}_l=\normalized{\vec{x}_2-\vec{x}_1}\);

  - local \(y\)-axis positioned arbitrarily, but in a deterministic manner: aligned with the \(xz\) plane (if \(\vec{n}_y<\vec{n}_z\)) or \(xy\) plane (otherwise);

  - local \(z\)-axis \(\vec{z}_l=\vec{x}_l\times\vec{y}_l\).

  If there has already been contact between the two spheres, it is updated to keep track of rigid motion of the contact (one that does not change mutual configuration of spheres) and mutual configuration changes. Rigid motion transforms local coordinate system and can be decomposed in rigid translation (affecting \(\vec{c}\)), and rigid rotation (affecting \(\mat{T}\)), which can be split in rotation \(\vec{o}_r\) perpendicular to the normal and rotation \(\vec{o}_t\) (``twist’’) parallel with the normal:

  \[\pprev{\vec{o}_r}=\prev{\vec{n}}\times\curr{\vec{n}}.\]

  Since velocities are known at previous midstep (\(t-\Dt/2\)), we consider mid-step normal

  \[\pprev{\vec{n}}=\frac{\prev{\vec{n}}+\curr{\vec{n}}}{2}.\]

  For the sake of numerical stability, \(\pprev{\vec{n}}\) is re-normalized after being computed, unless prohibited by approxMask. If approxMask has the appropriate bit set, the mid-normal is not compute, and we simply use \(\pprev{\vec{n}}\approx\prev{\vec{n}}\).

  Rigid rotation parallel with the normal is

  \[\pprev{\vec{o}_t}=\pprev{\vec{n}}\left(\pprev{\vec{n}}\cdot\frac{\pprev{\vec{\omega}}_1+\pprev{\vec{\omega}}_2}{2}\right)\Dt.\]

  Branch vectors \(\vec{b}_1\), \(\vec{b}_2\) (connecting \(\curr{\vec{x}}_1\), \(\curr{\vec{x}}_2\) with \(\curr{\vec{c}}\) are computed depending on noRatch (see here).

  \begin{align*} \vec{b}_1&=\begin{cases} r_1 \curr{\vec{n}} & \mbox{with }\texttt{noRatch} \\ \curr{\vec{c}}-\curr{\vec{x}}_1 & \mbox{otherwise} \end{cases} \\ \vec{b}_2&=\begin{cases} -r_2\curr{\vec{n}} & \mbox{with }\texttt{noRatch} \\ \curr{\vec{c}}-\curr{\vec{x}}_2 & \mbox{otherwise} \end{cases} \\ \end{align*}

  Relative velocity at \(\curr{\vec{c}}\) can be computed as

  \[\pprev{\vec{v}_r}=(\pprev{\vec{\tilde{v}}_2}+\vec{\omega}_2\times\vec{b}_2)-(\vec{v}_1+\vec{\omega}_1\times\vec{b}_1)\]

  where \(\vec{\tilde{v}}_2\) is \(\vec{v}_2\) without mean-field velocity gradient in periodic boundary conditions (see Cell.homoDeform). In the numerial implementation, the normal part of incident velocity is removed (since it is computed directly) with \(\pprev{\vec{v}_{r2}}=\pprev{\vec{v}_r}-(\pprev{\vec{n}}\cdot\pprev{\vec{v}_r})\pprev{\vec{n}}\).

  Any vector \(\vec{a}\) expressed in global coordinates transforms during one timestep as

  \[\curr{\vec{a}}=\prev{\vec{a}}+\pprev{\vec{v}_r}\Dt-\prev{\vec{a}}\times\pprev{\vec{o}_r}-\prev{\vec{a}}\times{\pprev{\vec{t}_r}}\]

  where the increments have the meaning of relative shear, rigid rotation normal to \(\vec{n}\) and rigid rotation parallel with \(\vec{n}\). Local coordinate system orientation, rotation matrix \(\mat{T}\), is updated by rows, i.e.

  \[\begin{split}\curr{\mat{T}}=\begin{pmatrix} \curr{\vec{n}_x}{\hspace{12mm}}\curr{\vec{n}_y}{\hspace{12mm}}\curr{\vec{n}_z} \\ {\prev{\mat{T}_{1,\bullet}}-\prev{\mat{T}_{1,\bullet}}\times\pprev{\vec{o}_r}-\prev{\mat{T}_{1,\bullet}}\times\pprev{\vec{o}_t}} \\ {\prev{\mat{T}_{2,\bullet}}-\prev{\mat{T}_{2,\bullet}}\times\pprev{\vec{o}_r}-\prev{\mat{T}_{,\bullet}}\times\pprev{\vec{o}_t}} \\ \end{pmatrix}\end{split}\]

  This matrix is re-normalized (unless prevented by approxMask) and mid-step transformation is computed using quaternion spherical interpolation as

  \[\pprev{\mat{T}}=\mathrm{Slerp}\,\left(\prev{\mat{T}};\curr{\mat{T}};t=1/2\right).\]

  Depending on approxMask, this computation can be avoided by approximating \(\pprev{\mat{T}}=\prev{\mat{T}}\).

  Finally, current displacement is evaluated as

  \[\curr{\vec{u}}=\prev{u}+\pprev{\mat{T}}\pprev{\vec{v}_r}\Dt.\]

  For the normal component, non-incremental evaluation is preferred, giving

  \[\curr{\vec{u}_x}=|\curr{\vec{x}_2}-\curr{\vec{x}_1}|-(r_1+r_2)\]

  If this functor is called for L6Geom, local rotation is updated as

  \[\curr{\vec{\phi}}=\prev{\vec{\phi}}+\pprev{\mat{T}}\Dt(\vec{\omega}_2-\vec{\omega}_1)\]
  property approxMask

    Selectively enable geometrical approximations (bitmask); add the values for approximations to be enabled.

    1 | use previous transformation to transform velocities (which are known at mid-steps), instead of mid-step transformation computed as quaternion slerp at t=0.5.
    2 | do not take average (mid-step) normal when computing relative shear displacement, use previous value instead
    4 | do not re-normalize average (mid-step) normal, if used.…

    By default, the mask is zero, wherefore none of these approximations is used.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property distFactor

    Create interaction if spheres are not futher than distFactor *(r1+r2). If negative, zero normal deformation will be set to be the initial value (otherwise, the geometrical distance is the ‘’zero’’ one).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property noRatch

    See Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property trsfRenorm

    How often to renormalize trsf; if non-positive, never renormalized (simulation might be unstable)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Sphere_Sphere_L6Geom(inherits Ig2_Sphere_Sphere_L3Geom → IGeomFunctor → Functor → Serializable)

  Incrementally compute L6Geom for contact of 2 spheres.

  property approxMask

    Selectively enable geometrical approximations (bitmask); add the values for approximations to be enabled.

    1 | use previous transformation to transform velocities (which are known at mid-steps), instead of mid-step transformation computed as quaternion slerp at t=0.5.
    2 | do not take average (mid-step) normal when computing relative shear displacement, use previous value instead
    4 | do not re-normalize average (mid-step) normal, if used.…

    By default, the mask is zero, wherefore none of these approximations is used.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property distFactor

    Create interaction if spheres are not futher than distFactor *(r1+r2). If negative, zero normal deformation will be set to be the initial value (otherwise, the geometrical distance is the ‘’zero’’ one).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property noRatch

    See Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property trsfRenorm

    How often to renormalize trsf; if non-positive, never renormalized (simulation might be unstable)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Sphere_Sphere_ScGeom(inherits IGeomFunctor → Functor → Serializable)

  Create/update a ScGeom instance representing the geometry of a contact point between two Spheres s.

  property avoidGranularRatcheting

    Define relative velocity so that ratcheting is avoided. It applies for sphere-sphere contacts. It eventualy also apply for sphere-emulating interactions (i.e. convertible into the ScGeom type), if the virtual sphere’s motion is defined correctly (see e.g. Ig2_Sphere_ChainedCylinder_CylScGeom).

    Short explanation of what we want to avoid :

    Numerical ratcheting is best understood considering a small elastic cycle at a contact between two grains : assuming b1 is fixed, impose this displacement to b2 :

    1. translation dx in the normal direction

    2. rotation a

    3. translation -dx (back to the initial position)

    4. rotation -a (back to the initial orientation)

    If the branch vector used to define the relative shear in rotation×branch is not constant (typically if it is defined from the vector center→contactPoint), then the shear displacement at the end of this cycle is not zero: rotations a and -a are multiplied by branches of different lengths.

    It results in a finite contact force at the end of the cycle even though the positions and orientations are unchanged, in total contradiction with the elastic nature of the problem. It could also be seen as an inconsistent energy creation or loss. Given that DEM simulations tend to generate oscillations around equilibrium (damped mass-spring), it can have a significant impact on the evolution of the packings, resulting for instance in slow creep in iterations under constant load.

    The solution adopted here to avoid ratcheting is as proposed by McNamara and co-workers. They analyzed the ratcheting problem in detail - even though they comment on the basis of a cycle that differs from the one shown above. One will find interesting discussions in e.g. [McNamara2008], even though solution it suggests is not fully applied here (equations of motion are not incorporating alpha, in contradiction with what is suggested by McNamara et al.).

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

    InteractionGeometry will be computed when interactionDetectionFactor*(rad1+rad2) > distance.

    Note

    This parameter is functionally coupled with Bo1_Sphere_Aabb::aabbEnlargeFactor, which will create larger bounding boxes and should be of the same value.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Sphere_Sphere_ScGeom6D(inherits Ig2_Sphere_Sphere_ScGeom → IGeomFunctor → Functor → Serializable)

  Create/update a ScGeom6D instance representing the geometry of a contact point between two Spheres, including relative rotations.

  property avoidGranularRatcheting

    Define relative velocity so that ratcheting is avoided. It applies for sphere-sphere contacts. It eventualy also apply for sphere-emulating interactions (i.e. convertible into the ScGeom type), if the virtual sphere’s motion is defined correctly (see e.g. Ig2_Sphere_ChainedCylinder_CylScGeom).

    Short explanation of what we want to avoid :

    Numerical ratcheting is best understood considering a small elastic cycle at a contact between two grains : assuming b1 is fixed, impose this displacement to b2 :

    1. translation dx in the normal direction

    2. rotation a

    3. translation -dx (back to the initial position)

    4. rotation -a (back to the initial orientation)

    If the branch vector used to define the relative shear in rotation×branch is not constant (typically if it is defined from the vector center→contactPoint), then the shear displacement at the end of this cycle is not zero: rotations a and -a are multiplied by branches of different lengths.

    It results in a finite contact force at the end of the cycle even though the positions and orientations are unchanged, in total contradiction with the elastic nature of the problem. It could also be seen as an inconsistent energy creation or loss. Given that DEM simulations tend to generate oscillations around equilibrium (damped mass-spring), it can have a significant impact on the evolution of the packings, resulting for instance in slow creep in iterations under constant load.

    The solution adopted here to avoid ratcheting is as proposed by McNamara and co-workers. They analyzed the ratcheting problem in detail - even though they comment on the basis of a cycle that differs from the one shown above. One will find interesting discussions in e.g. [McNamara2008], even though solution it suggests is not fully applied here (equations of motion are not incorporating alpha, in contradiction with what is suggested by McNamara et al.).

  property bases

    Ordered list of types (as strings) this functor accepts.

  property creep

    Substract rotational creep from relative rotation. The rotational creep ScGeom6D::twistCreep is a quaternion and has to be updated inside a constitutive law, see for instance Law2_ScGeom6D_CohFrictPhys_CohesionMoment.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property interactionDetectionFactor

    Enlarge both radii by this factor (if >1), to permit creation of distant interactions.

    InteractionGeometry will be computed when interactionDetectionFactor*(rad1+rad2) > distance.

    Note

    This parameter is functionally coupled with Bo1_Sphere_Aabb::aabbEnlargeFactor, which will create larger bounding boxes and should be of the same value.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property updateRotations

    Precompute relative rotations. Turning this false can speed up simulations when rotations are not needed in constitutive laws (e.g. when spheres are compressed without cohesion and moment in early stage of a triaxial test), but is not foolproof. Change this value only if you know what you are doing.

class yade.wrapper.Ig2_Tetra_Tetra_TTetraGeom(inherits IGeomFunctor → Functor → Serializable)

  Create/update geometry of collision between 2 tetrahedra (TTetraGeom instance)

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Wall_LevelSet_MultiScGeom(inherits IGeomFunctor → Functor → Serializable)

  Creates or updates a MultiScGeom instance representing the multiple contact points interaction kinematics of one LevelSet body with one Wall body, extending Ig2_Wall_LevelSet_ScGeom to non-convex LevelSet-shaped bodies. Relative orientation of wall wrt global axes is again not supported. TODO: time cost could / should be improved (wrt Ig2_LevelSet_LevelSet_MultiScGeom; jduriez note see aor8* and aor9*)

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Wall_LevelSet_ScGeom(inherits IGeomFunctor → Functor → Serializable)

  Creates or updates a ScGeom instance representing the intersection of one LevelSet-shaped body with one Wall-shaped body, where overlap is chosen to occur on the opposite wall side than the LevelSet body’s center. Contact normal is given by the wall normal (relative orientation of wall wrt global axes is not supported) while overlap and contact points are defined likewise to Ig2_LevelSet_LevelSet_ScGeom.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Wall_LevelSet_VolumeGeom(inherits IGeomFunctor → Functor → Serializable)

  Creates or updates a VolumeGeom instance representing the intersection of one LevelSet body with one Wall body, where overlap is chosen to occur on the opposite wall side than the LevelSet body’s center. Contact normal is given by the wall normal while overlap and contact points are defined likewise to Ig2_LevelSet_LevelSet_VolumeGeom.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property nRefineOctree

    The number of refinements performed by the Octree algorithm used to compute the overlap volume between two particles. Default is 5.

  property smearCoeffOctree

    Smearing coefficient for the smeared Heaviside step function in the overlap volume integration. The transition width, or smearing width, is equal to half the diagonal of the smallest integration cell divided by the smearing coefficient.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property useAABE

    If true, use the provided (locally) axis-aligned bounding ellipsoid (AABE) to reduce the potential overlap volume between the particles. Increases accuracy of the Octree algrithm because the smallest integration cells will be smaller.

class yade.wrapper.Ig2_Wall_PFacet_ScGeom(inherits Ig2_Wall_Sphere_ScGeom → IGeomFunctor → Functor → Serializable)

  Create/update a ScGeom instance representing intersection of Wall and PFacet.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property hertzian

    If True, the equivalent radius for the Wall (ScGeom.refR1) is chosen as 1e8 times the Sphere’s radius (closer to Hertzian therory, where it is infinite). Otherwise, it is chosen to be equal to the Sphere’s radius.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property noRatch

    Avoid granular ratcheting

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Wall_Sphere_L3Geom(inherits Ig2_Sphere_Sphere_L3Geom → IGeomFunctor → Functor → Serializable)

  Incrementally compute L3Geom for contact between Wall and Sphere. Uses attributes of Ig2_Sphere_Sphere_L3Geom.

  property approxMask

    Selectively enable geometrical approximations (bitmask); add the values for approximations to be enabled.

    1 | use previous transformation to transform velocities (which are known at mid-steps), instead of mid-step transformation computed as quaternion slerp at t=0.5.
    2 | do not take average (mid-step) normal when computing relative shear displacement, use previous value instead
    4 | do not re-normalize average (mid-step) normal, if used.…

    By default, the mask is zero, wherefore none of these approximations is used.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property distFactor

    Create interaction if spheres are not futher than distFactor *(r1+r2). If negative, zero normal deformation will be set to be the initial value (otherwise, the geometrical distance is the ‘’zero’’ one).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property noRatch

    See Ig2_Sphere_Sphere_ScGeom.avoidGranularRatcheting.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property trsfRenorm

    How often to renormalize trsf; if non-positive, never renormalized (simulation might be unstable)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ig2_Wall_Sphere_ScGeom(inherits IGeomFunctor → Functor → Serializable)

  Create/update a ScGeom instance representing intersection of Wall and Sphere.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property hertzian

    If True, the equivalent radius for the Wall (ScGeom.refR1) is chosen as 1e8 times the Sphere’s radius (closer to Hertzian therory, where it is infinite). Otherwise, it is chosen to be equal to the Sphere’s radius.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property noRatch

    Avoid granular ratcheting

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### IGeomDispatcher

class yade.wrapper.IGeomDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((IGeomDispatcher)arg1, (Shape)arg2, (Shape)arg3) → IGeomFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((IGeomDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

## Interaction Physics creation

### IPhysFunctor

Inheritance graph of IPhysFunctor.

class yade.wrapper.IPhysFunctor(inherits Functor → Serializable)

  Functor for creating/updating Interaction::phys objects from bodies’ material properties.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_2xInelastCohFrictMat_InelastCohFrictPhys(inherits IPhysFunctor → Functor → Serializable)

  Generates cohesive-frictional interactions with moments. Used in the contact law Law2_ScGeom6D_InelastCohFrictPhys_CohesionMoment.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_BubbleMat_BubbleMat_BubblePhys(inherits IPhysFunctor → Functor → Serializable)

  Generates bubble interactions.Used in the contact law Law2_ScGeom_BubblePhys_Bubble.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_CohFrictMatSeg_CohFrictMatSeg_CohFrictPhys(inherits IPhysFunctor → Functor → Serializable)

  This is a version of Ip2 to be used with CohFrictMatSeg (material with coating thickness-dependent properties). It generates cohesive-frictional interactions with moments, used in the contact law Law2_ScGeom6D_CohFrictPhys_CohesionMoment. For details regarding the computation of cohesion, twisting, bending, etc. please refer to Ip2_CohFrictMat_CohFrictMat_CohFrictPhys.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property setCohesionNow

    If true, assign cohesion to all existing contacts in current time-step. The flag is turned false automatically, so that assignment is done in the current timestep only.

  property setCohesionOnNewContacts

    If true, assign cohesion at all new contacts. If false, only existing contacts can be cohesive (also see Ip2_CohFrictMatSeg_CohFrictMatSeg_CohFrictPhys::setCohesionNow), and new contacts are only frictional.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_CohFrictMat_CohFrictMat_CohFrictPhys(inherits IPhysFunctor → Functor → Serializable)

  Generates cohesive-frictional interactions with moments, used in the contact law Law2_ScGeom6D_CohFrictPhys_CohesionMoment. The normal/shear stiffness and friction definitions are the same as in Ip2_FrictMat_FrictMat_FrictPhys, check the documentation there for details.

  Adhesions related to the normal and the shear components are calculated from CohFrictMat::normalCohesion (\(C_n\)) and CohFrictMat::shearCohesion (\(C_s\)). For particles of size \(R_1\),\(R_2\) the adhesion will be \(a_i=C_i min(R_1,R_2)^2\), \(i=n,s\).

  Twist and rolling stiffnesses are proportional to the shear stiffness through dimensionless factors alphaKtw and alphaKr, such that the rotational stiffnesses are defined by \(k_s \alpha_i R_1 R_2\), \(i=tw,r\). The adhesive contributions to rolling and twisting resistance are by default \(C_r=\frac{C_n}{4} min(R_1,R_2)^3\) and \(C_{tw}=\frac{C_s}{2} min(R_1,R_2)^3\) (inspired by the case of beams).

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property frictAngle

    Instance of MatchMaker determining how to compute interaction’s friction angle. If `None`, minimum value is used.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property normalCohesion

    Instance of MatchMaker determining tensile strength

  property rollingCohesion

    Instance of MatchMaker determining cohesive part of the rolling strength (a frictional term might be added depending on CohFrictPhys::cohesionDisablesFriction). The default is \(\frac{r}{4}R_t\) with \(R_t\) the shear strength (inspired by stress in beams with circular cross-section).

  setCohesion((Ip2_CohFrictMat_CohFrictMat_CohFrictPhys)arg1, (Interaction)interaction, (bool)cohesive, (bool)resetDisp) → None :

    Bond or un-bond an interaction with cohesion.

    > When `True`, the resulting state is the same as what is obtained by executing an InteractionLoop with the functor’s setCohesionNow or the interaction’s CohFrictPhys::initCohesion `True`. It will use the matchmakers if defined. The only difference is that calling this function explicitly will make the contact cohesive even if not both materials have CohFrictMat::isCohesive`=``True`.

    When `False`, the resulting state is the same as after breaking a fragile interaction. If resetDisp is `True`, the current distance is taken as the reference for computing normal displacement and normal force.

  property setCohesionNow

    If true, assign cohesion to all existing contacts in current time-step. The flag is turned false automatically, so that assignment is done in the current timestep only.

  property setCohesionOnNewContacts

    If true, assign cohesion at all new contacts. If false, only existing contacts can be cohesive (also see Ip2_CohFrictMat_CohFrictMat_CohFrictPhys::setCohesionNow), and new contacts are only frictional.

  property shearCohesion

    Instance of MatchMaker determining cohesive part of the shear strength (a frictional term might be added depending on CohFrictPhys::cohesionDisablesFriction)

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property twistingCohesion

    Instance of MatchMaker determining cohesive part of the twisting strength (a frictional term might be added depending on CohFrictPhys::cohesionDisablesFriction). The default is \(\frac{r}{2}R_s\) with \(R_s\) the shear strength (inspired by stress in beams with circular cross-section).

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_CpmMat_CpmMat_CpmPhys(inherits IPhysFunctor → Functor → Serializable)

  Convert 2 CpmMat instances to CpmPhys with corresponding parameters. Uses simple (arithmetic) averages if material are different. Simple copy of parameters is performed if the material is shared between both particles. See cpm-model for detals.

  property E

    Instance of MatchMaker determining how to compute interaction’s normal modulus. If `None`, average value is used.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property cohesiveThresholdIter

    Should new contacts be cohesive? They will before this iter#, they will not be afterwards. If 0, they will never be. If negative, they will always be created as cohesive (10 by default).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_ElastMat_ElastMat_NormPhys(inherits IPhysFunctor → Functor → Serializable)

  Create a NormPhys from two ElastMats. TODO. EXPERIMENTAL

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_ElastMat_ElastMat_NormShearPhys(inherits IPhysFunctor → Functor → Serializable)

  Create a NormShearPhys from two ElastMats. TODO. EXPERIMENTAL

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMatCDM_FrictMatCDM_MindlinPhysCDM(inherits IPhysFunctor → Functor → Serializable)

  Create a MindlinPhysCDM from two FrictMatCDMsExts.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property frictAngle

    Instance of MatchMaker determining how to compute interaction’s friction angle. If `None`, minimum value is used.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMat_CpmMat_FrictPhys(inherits IPhysFunctor → Functor → Serializable)

  Convert CpmMat instance and FrictMat instance to FrictPhys with corresponding parameters (young, poisson, frictionAngle). Uses simple (arithmetic) averages if material parameters are different.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property frictAngle

    See Ip2_FrictMat_FrictMat_FrictPhys.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMat_FrictMatCDM_MindlinPhysCDM(inherits IPhysFunctor → Functor → Serializable)

  Create a MindlinPhysCDM from one FrictMat and one FrictMatCDM instance.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property frictAngle

    Instance of MatchMaker determining how to compute interaction’s friction angle. If `None`, minimum value is used.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMat_FrictMat_CapillaryPhys(inherits IPhysFunctor → Functor → Serializable)

  RelationShips to use with Law2_ScGeom_CapillaryPhys_Capillarity.

  > In these RelationShips all the interaction attributes are computed.

  Warning

  as in the others Ip2 functors, most of the attributes are computed only once, when the interaction is new.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMat_FrictMat_FrictPhys(inherits IPhysFunctor → Functor → Serializable)

  Create a FrictPhys from two FrictMats. The compliance of one sphere under point load is defined here as \(1/(E.D)\), with \(E\) the stiffness of the sphere and \(D\) its diameter. The compliance of the contact itself is taken as the sum of compliances from each sphere, i.e. \(1/(E_1.D_1)+1/(E_2.D_2)\) in the general case, or \(2/(E.D)\) in the special case of equal sizes and equal stiffness. Note that summing compliances is equivalent to summing the harmonic average of stiffnesses. This reasoning is applied in both the normal and the tangential directions (as in e.g. [Scholtes2009a]), hence the general form of the contact stiffness:

  \(k = \frac{E_1D_1*E_2D_2}{E_1D_1+E_2D_2}=\frac{k_1*k_2}{k_1+k_2}\), with \(k_i=E_iD_i\).

  In the above equation \(E_i\) is taken equal to FrictMat::young of sphere \(i\) for the normal stiffness, and FrictMat::young \(\times\) ElastMat::poisson for the shear stiffness. In the case of a contact between a ViscElMat and a FrictMat, be sure to set FrictMat::young and FrictMat::poisson, otherwise the default value will be used.

  The contact friction is defined according to Ip2_FrictMat_FrictMat_FrictPhys::frictAngle (minimum of the two materials by default).

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property frictAngle

    Instance of MatchMaker determining how to compute interaction’s friction angle. If `None`, minimum value is used.

  property kn

    Instance of MatchMaker determining how to compute interaction’s normal stiffness. If `None`, harmonic average is used.

  property ks

    Instance of MatchMaker determining how to compute interaction’s shear stiffness. If `None`, harmonic average is used.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMat_FrictMat_KnKsPhys(inherits IPhysFunctor → Functor → Serializable)

  EXPERIMENTAL. Ip2 functor for KnKsPhys

  property Knormal

    Volumetric stiffness in the contact normal direction (units: stress/length)

  property Kshear

    Volumetric stiffness in the contact shear direction (units: stress/length)

  property bases

    Ordered list of types (as strings) this functor accepts.

  property brittleLength

    Shear length for degradation

  property cohesion

    Cohesion

  property cohesionBroken

    Whether cohesion is already broken

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property kn_i

    Currently, we assume kn_i and Knormal are adopting the same value in Ip2 initialisation

  property ks_i

    Currently, we assume ks_i and Kshear are adopting the same value in Ip2 initialisation

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property maxClosure

    not fully in use

  property phi_b

    Basic friction angle

  property tension

    Tension

  property tensionBroken

    Whether tension is already broken

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property useFaceProperties

    Whether to get face properties from the intersecting particles

  property viscousDamping

    Viscous damping ratio \(\beta_n\), see Ip2_FrictMat_FrictMat_MindlinPhys documentation

class yade.wrapper.Ip2_FrictMat_FrictMat_LubricationPhys(inherits IPhysFunctor → Functor → Serializable)

  Ip2 creating LubricationPhys from two Material instances.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property eps

    Roughness: fraction of radius enlargement for contact asperities

  property eta

    Fluid viscosity [Pa.s]

  property keps

    Dimensionless stiffness coefficient of the asperities, relative to the stiffness of the surface (the final stiffness will be keps*kn). Only used with resolution method=0, with resolution>0 it is always equal to 1. [-]

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMat_FrictMat_MindlinCapillaryPhys(inherits IPhysFunctor → Functor → Serializable)

  RelationShips to use with Law2_ScGeom_CapillaryPhys_Capillarity

  > In these RelationShips all the interaction attributes are computed.

  Warning

  as in the others Ip2 functors, most of the attributes are computed only once, when the interaction is new.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property betan

    Normal viscous damping ratio \(\beta_n\).

  property betas

    Shear viscous damping ratio \(\beta_s\).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property en

    Normal coefficient of restitution \(e_n\).

  property es

    Shear coefficient of restitution \(e_s\).

  property eta

    Coefficient to determine the plastic bending moment

  property gamma

    Surface energy parameter [J/m^2] per each unit contact surface, to derive DMT formulation from HM

  property krot

    Rotational stiffness for moment contact law

  property ktwist

    Torsional stiffness for moment contact law

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMat_FrictMat_MindlinPhys(inherits IPhysFunctor → Functor → Serializable)

  Calculate physical parameters needed to obtain the normal and shear stiffness values according to the Hertz-Mindlin formulation (no slip solution).\

  There are two available viscous damping models for (1) constant and (2) velocity-dependent coefficient of restitution. In both cases, the viscous forces are calculated as \(F_{n,viscous}=c_n \cdot v_n\) (\(F_{s,viscous}=c_s \cdot v_s\)), where \(c_n\) (\(c_s\)) the normal (shear) viscous damping coefficient and \(v_n\) (\(v_s\)) the normal (shear) component of the relative velocity.\

  1. Constant coefficient of restitution: The normal (shear) viscous damping coefficient is given by \(c_n=2 \cdot \beta_n \cdot \sqrt{m_{bar} \cdot k_n}\) (\(c_s=2 \cdot \beta_s \cdot \sqrt{m_{bar} \cdot k_s}\)), where \(m_{bar}\) the effective mass, \(\beta_n\) (\(\beta_s\)) normal (shear) viscous damping ratios, and \(k_{n}=2 \cdot E^* \cdot \sqrt{R^* \cdot \u_N}\) (\(k_{s}=8 \cdot G^* \cdot \sqrt{R \cdot u_N}\)) the normal (shear) tangential stiffness values, according to the formulations of Hertz and Mindlin, respectively, and \(R^*\), \(E^*\), \(G^*\) the effective radius, elastic and shear moduli of the interacting particles.

  The normal (shear) viscous damping coefficient \(c_n\) (\(c_s\)) can be specified either by providing the normal (shear) viscous damping ratio \(\beta_n\) (\(\beta_s\)), which is then assigned directly to MindlinPhys.betan (MindlinPhys.betas), or by defining the normal (shear) coefficient of restitution \(e_n\) (\(e_s\)) in which case the viscous damping ratios are computed using formula (B6) of [Thornton2013], written specifically for the Hertz-Mindlin model (no-slip solution) where the end of contact is considered to take place once the normal force is zero and not once the overlap is zero, thus not allowing attractive elastic forces for non-adhesive contacts, as also discussed in [Schwager2007].

  2. Velocity-dependent coefficient of restitution: The viscous damping coefficients are given by \(c_n=c_s=A \cdot k_n\), where \(A\) a dissipative constant. To calculate this constant, the user has to provide a coefficient of restitution (\(e_n\)) and an impact velocity (\(v_n\)) corresponding to this \(e_n\), as described in [Mueller2011].

  The following rules apply: # It is an error to specify both \(e_n\) and \(\beta_n\) (\(e_s\) and \(\beta_s\)) or both \(v_n\) and \(\beta_n\).

  # If neither \(e_n\) nor \(\beta_n\) is given, then MindlinPhys.betan will be zero and no viscous damping will be considered.

  # If neither \(e_s\) nor \(\beta_s\) is given, the value of Ip2_FrictMat_FrictMat_MindlinPhys.en is used for Ip2_FrictMat_FrictMat_MindlinPhys.es and the value of MindlinPhys.betan is used for MindlinPhys.betas, respectively.

  The \(e_n\), \(\beta_n\), \(e_s\), \(\beta_s\), \(v_n\) are MatchMaker objects; they can be constructed from float values to always return constant values.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property betan

    Normal viscous damping ratio \(\beta_n\).

  property betas

    Shear viscous damping ratio \(\beta_s\).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property en

    Normal coefficient of restitution \(e_n\).

  property es

    Shear coefficient of restitution \(e_s\).

  property eta

    Coefficient to determine the plastic bending moment

  property frictAngle

    Instance of MatchMaker determining how to compute the friction angle of an interaction. If `None`, minimum value is used.

  property gamma

    Surface energy parameter [J/m^2] per each unit contact surface, to derive DMT formulation from HM

  property krot

    Rotational stiffness for moment contact law

  property ktwist

    Torsional stiffness for moment contact law

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vn

    Impact velocity corresponding to the en value to calculate the dissipative constant \(An\) used in the viscous damping model of [Mueller2011].

class yade.wrapper.Ip2_FrictMat_FrictMat_MultiFrictPhys(inherits IPhysFunctor → Functor → Serializable)

  Handles the MultiFrictPhys physical description of the contact between two FrictMats. Contact stiffnesses (for every contact) are directly assigned from below attributes, independent of FrictMat properties. Contact friction angle is taken as the minimum of the 2 material friction angles (FrictMat.frictionAngle).

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property kn

    Chosen value for MultiFrictPhys.kn

  property ks

    Chosen value for MultiFrictPhys.ks

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMat_FrictMat_ViscoFrictPhys(inherits Ip2_FrictMat_FrictMat_FrictPhys → IPhysFunctor → Functor → Serializable)

  Create a FrictPhys from two FrictMats. The compliance of one sphere under symetric point loads is defined here as 1/(E.r), with E the stiffness of the sphere and r its radius, and corresponds to a compliance 1/(2.E.r)=1/(E.D) from each contact point. The compliance of the contact itself will be the sum of compliances from each sphere, i.e. 1/(E.D1)+1/(E.D2) in the general case, or 1/(E.r) in the special case of equal sizes. Note that summing compliances corresponds to an harmonic average of stiffnesss, which is how kn is actually computed in the Ip2_FrictMat_FrictMat_FrictPhys functor.

  The shear stiffness ks of one sphere is defined via the material parameter ElastMat::poisson, as ks=poisson*kn, and the resulting shear stiffness of the interaction will be also an harmonic average.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property frictAngle

    Instance of MatchMaker determining how to compute interaction’s friction angle. If `None`, minimum value is used.

  property kn

    Instance of MatchMaker determining how to compute interaction’s normal stiffness. If `None`, harmonic average is used.

  property ks

    Instance of MatchMaker determining how to compute interaction’s shear stiffness. If `None`, harmonic average is used.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictMat_FrictViscoMat_FrictViscoPhys(inherits IPhysFunctor → Functor → Serializable)

  Converts a FrictMat and FrictViscoMat instance to FrictViscoPhys with corresponding parameters. Basically this functor corresponds to Ip2_FrictMat_FrictMat_FrictPhys with the only difference that damping in normal direction can be considered.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property frictAngle

    Instance of MatchMaker determining how to compute interaction’s friction angle. If `None`, minimum value is used.

  property kRatio

    Instance of MatchMaker determining how to compute interaction’s shear contact stiffnesses. If this value is not given the elastic properties (i.e. poisson) of the two colliding materials are used to calculate the stiffness.

  property kn

    Instance of MatchMaker determining how to compute interaction’s normal contact stiffnesses. If this value is not given the elastic properties (i.e. young) of the two colliding materials are used to calculate the stiffness.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_FrictViscoMat_FrictViscoMat_FrictViscoPhys(inherits IPhysFunctor → Functor → Serializable)

  Converts 2 FrictViscoMat instances to FrictViscoPhys with corresponding parameters. Basically this functor corresponds to Ip2_FrictMat_FrictMat_FrictPhys with the only difference that damping in normal direction can be considered.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property frictAngle

    Instance of MatchMaker determining how to compute interaction’s friction angle. If `None`, minimum value is used.

  property kRatio

    Instance of MatchMaker determining how to compute interaction’s shear contact stiffnesses. If this value is not given the elastic properties (i.e. poisson) of the two colliding materials are used to calculate the stiffness.

  property kn

    Instance of MatchMaker determining how to compute interaction’s normal contact stiffnesses. If this value is not given the elastic properties (i.e. young) of the two colliding materials are used to calculate the stiffness.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_JCFpmMat_JCFpmMat_JCFpmPhys(inherits IPhysFunctor → Functor → Serializable)

  Converts 2 JCFpmMat instances to one JCFpmPhys instance, with corresponding parameters. See JCFpmMat and [Duriez2016] for details

  property bases

    Ordered list of types (as strings) this functor accepts.

  property cohesiveTresholdIteration

    should new contacts be cohesive? If strictly negativ, they will in any case. If positiv, they will before this iter, they won’t afterward.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property weibullCutOffMax

    Factor that cuts off the largest values of the weibull distributed interaction areas.

  property weibullCutOffMin

    Factor that cuts off the smallest values of the weibull distributed interaction areas.

  property xSectionWeibullScaleParameter

    Scale parameter used to generate interaction radii for the crosssectional areas (changing strength criteria only) according to Weibull distribution. Activated for any value other than 0. Needs to be combined with a shape parameter

  property xSectionWeibullShapeParameter

    Shape parameter used to generate interaction radii for the crossSectional areas (changing strength criteria only) according to Weibull distribution. Activated for any value other than 0. Needs to be combined with a scale parameter)

class yade.wrapper.Ip2_LudingMat_LudingMat_LudingPhys(inherits IPhysFunctor → Functor → Serializable)

  Convert 2 instances of LudingMat to LudingPhys using the rule of consecutive connection.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_MortarMat_MortarMat_MortarPhys(inherits IPhysFunctor → Functor → Serializable)

  Ip2 creating MortarPhys from two MortarMat instances.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property cohesiveThresholdIter

    Should new contacts be cohesive? They will before this iter#, they will not be afterwards. If <=0, they will never be.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_ViscElCapMat_ViscElCapMat_ViscElCapPhys(inherits Ip2_ViscElMat_ViscElMat_ViscElPhys → IPhysFunctor → Functor → Serializable)

  Convert 2 instances of ViscElCapMat to ViscElCapPhys using the rule of consecutive connection.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property en

    Instance of MatchMaker determining restitution coefficient in normal direction

  property et

    Instance of MatchMaker determining restitution coefficient in tangential direction

  property frictAngle

    Instance of MatchMaker determining how to compute interaction’s friction angle. If `None`, minimum value is used.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property tc

    Instance of MatchMaker determining contact time

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_ViscElMat_ViscElMat_MultiViscElPhys(inherits IPhysFunctor → Functor → Serializable)

  Handles the MultiViscElPhys physical description of the contact between two ViscElMats. Contact stiffnesses (for every contact) are directly assigned from below attributes, independent of ViscElMat properties. Contact friction angle is taken as the minimum of the 2 material friction angles (ViscElMat.frictionAngle).

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property en

    Instance of MatchMaker determining how to compute interaction’s normal coefficient of restitution. If `None`, harmonic average is used.

  property et

    Instance of MatchMaker determining how to compute interaction’s shear coefficient of restitution. If `None`, harmonic average is used.

  property kn

    Instance of MatchMaker determining how to compute interaction’s normal stiffness. If `None`, harmonic average is used.

  property ks

    Instance of MatchMaker determining how to compute interaction’s shear stiffness. If `None`, harmonic average is used.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_ViscElMat_ViscElMat_ViscElPhys(inherits IPhysFunctor → Functor → Serializable)

  Convert 2 instances of ViscElMat to ViscElPhys using the rule of consecutive connection.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property en

    Instance of MatchMaker determining restitution coefficient in normal direction

  property et

    Instance of MatchMaker determining restitution coefficient in tangential direction

  property frictAngle

    Instance of MatchMaker determining how to compute interaction’s friction angle. If `None`, minimum value is used.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property tc

    Instance of MatchMaker determining contact time

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Ip2_WireMat_WireMat_WirePhys(inherits IPhysFunctor → Functor → Serializable)

  Converts 2 WireMat instances to WirePhys with corresponding parameters.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property linkThresholdIteration

    Iteration to create the link.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### IPhysDispatcher

class yade.wrapper.IPhysDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((IPhysDispatcher)arg1, (Material)arg2, (Material)arg3) → IPhysFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((IPhysDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

## Constitutive laws

### LawFunctor

Inheritance graph of LawFunctor.

class yade.wrapper.LawFunctor(inherits Functor → Serializable)

  Functor for applying constitutive laws on interactions.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ChCylGeom6D_CohFrictPhys_CohesionMoment(inherits LawFunctor → Functor → Serializable)

  Law for linear compression, and Mohr-Coulomb plasticity surface without cohesion. This law implements the classical linear elastic-plastic law from [CundallStrack1979] (see also [Pfc3dManual30]). The normal force is (with the convention of positive tensile forces) \(F_n=\min(k_n u_n, 0)\). The shear force is \(F_s=k_s u_s\), the plasticity condition defines the maximum value of the shear force : \(F_s^{\max}=F_n\tan(\phi)\), with \(\phi\) the friction angle.

  Note

  This law is well tested in the context of triaxial simulation, and has been used for a number of published results (see e.g. [Scholtes2009b] and other papers from the same authors). It is generalised by Law2_ScGeom6D_CohFrictPhys_CohesionMoment, which adds cohesion and moments at contact.

  property always_use_moment_law

    If true, use bending/twisting moments at all contacts. If false, compute moments only for cohesive contacts.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property creep_viscosity

    creep viscosity [Pa.s/m]. probably should be moved to Ip2_CohFrictMat_CohFrictMat_CohFrictPhys…

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property shear_creep

    activate creep on the shear force, using CohesiveFrictionalContactLaw::creep_viscosity.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property twist_creep

    activate creep on the twisting moment, using CohesiveFrictionalContactLaw::creep_viscosity.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property useIncrementalForm

    use the incremental formulation to compute bending and twisting moments. Creep on the twisting moment is not included in such a case.

class yade.wrapper.Law2_CylScGeom6D_CohFrictPhys_CohesionMoment(inherits LawFunctor → Functor → Serializable)

  This law generalises Law2_CylScGeom_FrictPhys_CundallStrack by adding cohesion and moments at contact.

  property always_use_moment_law

    If true, use bending/twisting moments at all contacts. If false, compute moments only for cohesive contacts.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property creep_viscosity

    creep viscosity [Pa.s/m]. probably should be moved to Ip2_CohFrictMat_CohFrictMat_CohFrictPhys…

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property shear_creep

    activate creep on the shear force, using CohesiveFrictionalContactLaw::creep_viscosity.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property twist_creep

    activate creep on the twisting moment, using CohesiveFrictionalContactLaw::creep_viscosity.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property useIncrementalForm

    use the incremental formulation to compute bending and twisting moments. Creep on the twisting moment is not included in such a case.

class yade.wrapper.Law2_CylScGeom_FrictPhys_CundallStrack(inherits LawFunctor → Functor → Serializable)

  Law for linear compression, and Mohr-Coulomb plasticity surface without cohesion. This law implements the classical linear elastic-plastic law from [CundallStrack1979] (see also [Pfc3dManual30]). The normal force is (with the convention of positive tensile forces) \(F_n=\min(k_n u_n, 0)\). The shear force is \(F_s=k_s u_s\), the plasticity condition defines the maximum value of the shear force : \(F_s^{\max}=F_n\tan(\phi)\), with \(\phi\) the friction angle.

  Note

  This law uses ScGeom.

  Note

  This law is well tested in the context of triaxial simulation, and has been used for a number of published results (see e.g. [Scholtes2009b] and other papers from the same authors). It is generalised by Law2_ScGeom6D_CohFrictPhys_CohesionMoment, which adds cohesion and moments at contact.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_GridCoGridCoGeom_FrictPhys_CundallStrack(inherits Law2_ScGeom_FrictPhys_CundallStrack → LawFunctor → Functor → Serializable)

  Frictional elastic contact law between two gridConnection . See Law2_ScGeom_FrictPhys_CundallStrack for more details.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  elasticEnergy((Law2_ScGeom_FrictPhys_CundallStrack)arg1) → float :

    Compute and return the total elastic energy in all “FrictPhys” contacts

  initPlasticDissipation((Law2_ScGeom_FrictPhys_CundallStrack)arg1, (float)arg2) → None :

    Initialize cummulated plastic dissipation to a value (0 by default).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  plasticDissipation((Law2_ScGeom_FrictPhys_CundallStrack)arg1) → float :

    Total energy dissipated in plastic slips at all FrictPhys contacts. Computed only if Law2_ScGeom_FrictPhys_CundallStrack::traceEnergy is true.

  property sphericalBodies

    If true, compute branch vectors from radii (faster), else use contactPoint-position. Turning this flag true is safe for sphere-sphere contacts and a few other specific cases. It will give wrong values of torques on facets or boxes.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property traceEnergy

    Define the total energy dissipated in plastic slips at all contacts. This will trace only plastic energy in this law, see O.trackEnergy for a more complete energies tracing

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_L3Geom_FrictPhys_ElPerfPl(inherits LawFunctor → Functor → Serializable)

  Basic law for testing L3Geom; it bears no cohesion (unless noBreak is `True`), and plastic slip obeys the Mohr-Coulomb criterion (unless noSlip is `True`).

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property noBreak

    Do not break contacts when particles separate.

  property noSlip

    No plastic slipping.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_L6Geom_FrictPhys_Linear(inherits Law2_L3Geom_FrictPhys_ElPerfPl → LawFunctor → Functor → Serializable)

  Basic law for testing L6Geom – linear in both normal and shear sense, without slip or breakage.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property charLen

    Characteristic length with the meaning of the stiffness ratios bending/shear and torsion/normal.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property noBreak

    Do not break contacts when particles separate.

  property noSlip

    No plastic slipping.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_MultiScGeom_MultiFrictPhys_CundallStrack(inherits Law2_ScGeom_FrictPhys_CundallStrack → LawFunctor → Functor → Serializable)

  Applies Law2_ScGeom_FrictPhys_CundallStrack at each contact point of a (yref:MultiScGeom;yref:MultiFrictPhys) contact [Duriez2023].

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  elasticEnergy((Law2_ScGeom_FrictPhys_CundallStrack)arg1) → float :

    Compute and return the total elastic energy in all “FrictPhys” contacts

  initPlasticDissipation((Law2_ScGeom_FrictPhys_CundallStrack)arg1, (float)arg2) → None :

    Initialize cummulated plastic dissipation to a value (0 by default).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  plasticDissipation((Law2_ScGeom_FrictPhys_CundallStrack)arg1) → float :

    Total energy dissipated in plastic slips at all FrictPhys contacts. Computed only if Law2_ScGeom_FrictPhys_CundallStrack::traceEnergy is true.

  property sphericalBodies

    If true, compute branch vectors from radii (faster), else use contactPoint-position. Turning this flag true is safe for sphere-sphere contacts and a few other specific cases. It will give wrong values of torques on facets or boxes.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property traceEnergy

    Define the total energy dissipated in plastic slips at all contacts. This will trace only plastic energy in this law, see O.trackEnergy for a more complete energies tracing

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_MultiScGeom_MultiViscElPhys_Basic(inherits Law2_ScGeom_ViscElPhys_Basic → LawFunctor → Functor → Serializable)

  Applies Law2_ScGeom_ViscElPhys_Basic at each contact point of a (yref:MultiScGeom;yref:MultiViscElPhys) contact [Duriez2023].

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_SCG_KnKsPhys_KnKsLaw(inherits LawFunctor → Functor → Serializable)

  Law for linear compression, without cohesion and Mohr-Coulomb plasticity surface.

  Note

  This law uses ScGeom; there is also functionally equivalent Law2_Dem3DofGeom_FrictPhys_Basic, which uses Dem3DofGeom (sphere-box interactions are not implemented for the latest).

  property Talesnick

    Use contact law developed for validation against model test

  property allowBreakage

    Allow cohesion to break. Once broken, cohesion = 0

  property allowViscousAttraction

    Whether to allow attractive forces due to viscous damping

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  elasticEnergy((Law2_SCG_KnKsPhys_KnKsLaw)arg1) → float :

    Compute and return the total elastic energy in all “FrictPhys” contacts. Computed only if Law2_SCG_KnKsPhys_KnKsLaw::traceEnergy is true.

  initPlasticDissipation((Law2_SCG_KnKsPhys_KnKsLaw)arg1, (float)arg2) → None :

    Initialize cummulated plastic dissipation to a value (0 by default).

  property initialOverlapDistance

    Initial overlap distance, defining the offset distance for tension overlap, i.e. negative overlap.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  normDampDissip((Law2_SCG_KnKsPhys_KnKsLaw)arg1) → float :

    Total energy dissipated in normal viscous damping. Computed only if Law2_SCG_KnKsPhys_KnKsLaw::traceEnergy is true.

  plasticDissipation((Law2_SCG_KnKsPhys_KnKsLaw)arg1) → float :

    Total energy dissipated in plastic slips at all FrictPhys contacts. Computed only if Law2_SCG_KnKsPhys_KnKsLaw::traceEnergy is true.

  property preventGranularRatcheting

    bool to avoid granular ratcheting

  ratioSlidingContacts((Law2_SCG_KnKsPhys_KnKsLaw)arg1) → float :

    Return the ratio between the number of contacts sliding to the total number at a given time.

  shearDampDissip((Law2_SCG_KnKsPhys_KnKsLaw)arg1) → float :

    Total energy dissipated in shear viscous damping. Computed only if Law2_SCG_KnKsPhys_KnKsLaw::traceEnergy is true.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property traceEnergy

    Define the total energy dissipated in plastic slips at all contacts.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom6D_CohFrictPhys_CohesionMoment(inherits LawFunctor → Functor → Serializable)

  Law for linear traction-compression-bending-twisting, with cohesion+friction and Mohr-Coulomb plasticity surface. This law adds adhesion and moments to Law2_ScGeom_FrictPhys_CundallStrack.

  The normal force is (with the convention of positive tensile forces) \(F_n=min(k_n*(u_n-u_n^p), a_n)\), with \(a_n\) the normal adhesion and \(u_n^p\) the plastic part of normal displacement. The shear force is \(F_s=k_s*u_s\), the plasticity condition defines the maximum value of the shear force, by default \(F_s^{max}=F_n*tan(\phi)+a_s\), with \(\phi\) the friction angle and \(a_s\) the shear adhesion. If CohFrictPhys::cohesionDisablesFriction is True, friction is ignored as long as adhesion is active, and the maximum shear force is only \(F_s^{max}=a_s\).

  If the maximum tensile or maximum shear force is reached and CohFrictPhys::fragile =True (default), the cohesive link is broken, and \(a_n, a_s\) are set back to zero. If a tensile force is present, the contact is lost, else the shear strength is \(F_s^{max}=F_n*tan(\phi)\). If CohFrictPhys::fragile =False, the behaviour is perfectly plastic, and the shear strength is kept constant.

  If Law2_ScGeom6D_CohFrictPhys_CohesionMoment::momentRotationLaw =True, bending and twisting moments are computed using a linear law with moduli respectively \(k_b\) and \(k_t\), so that the moments are : \(M_b=k_b*\Theta_b\) and \(M_t=k_t*\Theta_t\), with \(\Theta_{b,t}\) the relative rotations between interacting bodies (details can be found in [Bourrier2013]). The maximum values of the moments depend on constant terms (CohFrictPhys::rollingAdhesion and CohFrictPhys::twistingAdhesion) and on terms which depend on the normal force \(F_n\) through the generalized friction coefficients CohFrictPhys::maxRollPl and CohFrictPhys::maxTwistPl; the instantaneous rolling resistance is thus \(a - F_n*\eta\) if \(a\) is adhesion and \(\eta\) is the friction coefficient.

  Creep at contact is implemented in this law, as defined in [Hassan2010]. If activated, there is a viscous behaviour of the shear and twisting components, and the evolution of the elastic parts of shear displacement and relative twist is given by \(du_{s,e}/dt=-F_s/\nu_s\) and \(d\Theta_{t,e}/dt=-M_t/\nu_t\).

  For turning adhesion on or off during a simulation, see Ip2_CohFrictMat_CohFrictMat_CohFrictPhys::setCohesion (subsequently, it is possible to modify the adhesion values directly, e.g. i.phys.shearAdhesion=…)

  property always_use_moment_law

    If false, compute moments only for cohesive contacts, broken contacts will have only normal and shear forces. If true, compute bending/twisting moments at all contacts and use the frictional coefficients CohFrictMat::etaRoll and CohFrictMat::etaTwist to define the strength of the broken contacts.

  property bases

    Ordered list of types (as strings) this functor accepts.

  bendingElastEnergy((Law2_ScGeom6D_CohFrictPhys_CohesionMoment)arg1) → float :

    Compute bending elastic energy.

  checkConsistency((Law2_ScGeom6D_CohFrictPhys_CohesionMoment)arg1, (CohFrictPhys)ip, (int)id1, (int)id2) → None :

    Runs consistency checks on an interaction physics and warn if some issues are suspected (e.g. if there is finite cohesion on the shear force and pure elasticity on bending moment). Most inconsistencies should occur when interaction properties are modified in a script; they are not supposed to result from the interaction loop, else please report the bug. This function is called automatically by the law functor on the first instance of a cohesive interaction. To call it in a script: law.checkConsistency(i.phys,i.id1,i.id2).

  property creep_viscosity

    creep viscosity [Pa.s/m]. probably should be moved to Ip2_CohFrictMat_CohFrictMat_CohFrictPhys.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  elasticEnergy((Law2_ScGeom6D_CohFrictPhys_CohesionMoment)arg1) → float :

    Compute total elastic energy.

  initPlasticDissipation((Law2_ScGeom6D_CohFrictPhys_CohesionMoment)arg1, (float)arg2) → None :

    Initialize cummulated plastic dissipation to a value (0 by default).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  normElastEnergy((Law2_ScGeom6D_CohFrictPhys_CohesionMoment)arg1) → float :

    Compute normal elastic energy.

  plasticDissipation((Law2_ScGeom6D_CohFrictPhys_CohesionMoment)arg1) → float :

    Total energy dissipated in plastic slips at all CohFrictPhys contacts. Computed only if Law2_ScGeom_FrictPhys_CundallStrack::traceEnergy is true.

  shearElastEnergy((Law2_ScGeom6D_CohFrictPhys_CohesionMoment)arg1) → float :

    Compute shear elastic energy.

  property shear_creep

    activate creep on the shear force, using CohesiveFrictionalContactLaw::creep_viscosity.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property traceEnergy

    Define the total energy dissipated in plastic slips at contacts. Note that it will not reflect any energy associated to de-bonding, as it may occur for fragile contacts, nor does it include plastic dissipation in traction.

  twistElastEnergy((Law2_ScGeom6D_CohFrictPhys_CohesionMoment)arg1) → float :

    Compute twist elastic energy.

  property twist_creep

    activate creep on the twisting moment, using CohesiveFrictionalContactLaw::creep_viscosity.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property useIncrementalForm

    use the incremental formulation to compute bending and twisting moments. Creep on the twisting moment is not included in such a case.

class yade.wrapper.Law2_ScGeom6D_InelastCohFrictPhys_CohesionMoment(inherits LawFunctor → Functor → Serializable)

  This law is currently under developpement. Final version and documentation will come before the end of 2014.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  normElastEnergy((Law2_ScGeom6D_InelastCohFrictPhys_CohesionMoment)arg1) → float :

    Compute normal elastic energy.

  shearElastEnergy((Law2_ScGeom6D_InelastCohFrictPhys_CohesionMoment)arg1) → float :

    Compute shear elastic energy.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_BubblePhys_Bubble(inherits LawFunctor → Functor → Serializable)

  Constitutive law for Bubble model.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property pctMaxForce

    Chan[2011] states the contact law is valid only for small interferences; therefore an exponential force-displacement curve models the contact stiffness outside that regime (large penetration). This artificial stiffening ensures that bubbles will not pass through eachother or completely overlap during the simulation. The maximum force is Fmax = (2*pi*surfaceTension*rAvg). pctMaxForce is the percentage of the maximum force dictates the separation threshold, Dmax, for each contact. Penetrations less than Dmax calculate the reaction force from the derived contact law, while penetrations equal to or greater than Dmax calculate the reaction force from the artificial exponential curve.

  property surfaceTension

    The surface tension in the liquid surrounding the bubbles. The default value is that of water at 25 degrees Celcius.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_CpmPhys_Cpm(inherits LawFunctor → Functor → Serializable)

  Constitutive law for the cpm-model.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  elasticEnergy((Law2_ScGeom_CpmPhys_Cpm)arg1) → float :

    Compute and return the total elastic energy in all “CpmPhys” contacts

  property epsSoft

    Strain at which softening in compression starts (non-negative to deactivate). The default value is such that plasticity does not occur

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property omegaThreshold

    damage after which the contact disappears (<1), since omega reaches 1 only for strain →+∞

  property relKnSoft

    Relative rigidity of the softening branch in compression (0=perfect elastic-plastic, <0 softening, >0 hardening)

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property yieldEllipseShift

    horizontal scaling of the ellipse (shifts on the +x axis as interactions with +y are given)

  property yieldLogSpeed

    scaling in the logarithmic yield surface (should be <1 for realistic results; >=0 for meaningful results)

  yieldSigmaTMagnitude((Law2_ScGeom_CpmPhys_Cpm)arg1, (float)sigmaN, (float)omega, (float)undamagedCohesion, (float)tanFrictionAngle) → float :

    Return radius of yield surface for given material and state parameters; uses attributes of the current instance (yieldSurfType etc), change them before calling if you need that.

  property yieldSurfType

    yield function: 0: mohr-coulomb (original); 1: parabolic; 2: logarithmic, 3: log+lin_tension, 4: elliptic, 5: elliptic+log

class yade.wrapper.Law2_ScGeom_FrictPhys_CundallStrack(inherits LawFunctor → Functor → Serializable)

  Law for linear compression, and Mohr-Coulomb plasticity surface without cohesion. This law implements the classical linear elastic-plastic law from [CundallStrack1979] (see also [Pfc3dManual30]). The normal force is (with the convention of positive tensile forces) \(F_n=\min(k_n u_n, 0)\). The shear force is \(F_s=k_s u_s\), the plasticity condition defines the maximum value of the shear force : \(F_s^{\max}=F_n\tan(\phi)\), with \(\phi\) the friction angle.

  This law is well tested in the context of triaxial simulation, and has been used for a number of published results (see e.g. [Scholtes2009b] and other papers from the same authors). It is generalised by Law2_ScGeom6D_CohFrictPhys_CohesionMoment, which adds cohesion and moments at contact.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  elasticEnergy((Law2_ScGeom_FrictPhys_CundallStrack)arg1) → float :

    Compute and return the total elastic energy in all “FrictPhys” contacts

  initPlasticDissipation((Law2_ScGeom_FrictPhys_CundallStrack)arg1, (float)arg2) → None :

    Initialize cummulated plastic dissipation to a value (0 by default).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  plasticDissipation((Law2_ScGeom_FrictPhys_CundallStrack)arg1) → float :

    Total energy dissipated in plastic slips at all FrictPhys contacts. Computed only if Law2_ScGeom_FrictPhys_CundallStrack::traceEnergy is true.

  property sphericalBodies

    If true, compute branch vectors from radii (faster), else use contactPoint-position. Turning this flag true is safe for sphere-sphere contacts and a few other specific cases. It will give wrong values of torques on facets or boxes.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property traceEnergy

    Define the total energy dissipated in plastic slips at all contacts. This will trace only plastic energy in this law, see O.trackEnergy for a more complete energies tracing

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_FrictViscoPhys_CundallStrackVisco(inherits LawFunctor → Functor → Serializable)

  Constitutive law for the FrictViscoPM. Corresponds to Law2_ScGeom_FrictPhys_CundallStrack with the only difference that viscous damping in normal direction can be considered.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  elasticEnergy((Law2_ScGeom_FrictViscoPhys_CundallStrackVisco)arg1) → float :

    Compute and return the total elastic energy in all “FrictViscoPhys” contacts

  initPlasticDissipation((Law2_ScGeom_FrictViscoPhys_CundallStrackVisco)arg1, (float)arg2) → None :

    Initialize cummulated plastic dissipation to a value (0 by default).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  plasticDissipation((Law2_ScGeom_FrictViscoPhys_CundallStrackVisco)arg1) → float :

    Total energy dissipated in plastic slips at all FrictPhys contacts. Computed only if :yref:Law2_ScGeom_FrictViscoPhys_CundallStrackVisco::traceEnergy` is true.

  property sphericalBodies

    If true, compute branch vectors from radii (faster), else use contactPoint-position. Turning this flag true is safe for sphere-sphere contacts and a few other specific cases. It will give wrong values of torques on facets or boxes.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property traceEnergy

    Define the total energy dissipated in plastic slips at all contacts. This will trace only plastic energy in this law, see O.trackEnergy for a more complete energies tracing

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_ImplicitLubricationPhys(inherits Law2_ScGeom_VirtualLubricationPhys → LawFunctor → Functor → Serializable)

  Material law for lubrication and contact between two spheres, solved using implicit method. The full description of this contact law is available in [Chevremont2020] . Several resolution methods are available. Iterative exact, solving the 2nd order polynomia. Other resolutions methods are numerical (Newton-Rafson and Dichotomy) with a variable change \(\delta=\log(u)\), solved in dimentionless coordinates.

  property MaxDist

    Maximum distance (d/a) for the interaction

  property MaxIter

    Maximum iterations for numerical resolution (Dichotomy and Newton-Rafson)

  property SolutionTol

    Tolerance for numerical resolution (Dichotomy and Newton-Rafson)

  property activateRollLubrication

    Activate roll lubrication (default: true)

  property activateTangencialLubrication

    Activate tangencial lubrication (default: true)

  property activateTwistLubrication

    Activate twist lubrication (default: true)

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  static getStressForEachBody() → tuple :

    Get stresses tensors for each bodies: normal contact stress, shear contact stress, normal lubrication stress, shear lubrication stress, stress from additionnal potential forces.

  static getTotalStresses() → tuple :

    Get total stresses tensors: normal contact stress, shear contact stress, normal lubrication stress, shear lubrication stress, stress from additionnal potential forces.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property maxSubSteps

    max recursion depth of adaptative timestepping in the theta-method, the minimal time interval is thus Omega::dt\(/2^{depth}\). If still not converged the integrator will switch to backward Euler.

  property resolution

    Change normal component resolution method, 0: Iterative exact resolution with substepping (theta method, linear contact), 1: Newton-Rafson dimensionless resolution (theta method, linear contact), 2: (default) Dichotomy dimensionless resolution (theta method, linear contact), 3: Exact dimensionless solution with contact prediction (theta method, linear contact). Method 3 is better if the volumic fraction is not too high. Use 2 otherwise.

  property theta

    parameter of the ‘theta’-method, 1: backward Euler, 0.5: trapezoidal rule, 0: not used, 0.55: suggested optimum)

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_JCFpmPhys_JointedCohesiveFrictionalPM(inherits LawFunctor → Functor → Serializable)

  Interaction law for cohesive frictional material, e.g. rock, possibly presenting joint surfaces, that can be mechanically described with a smooth contact logic [Ivars2011] (implemented in Yade in [Scholtes2012]). See examples/jointedCohesiveFrictionalPM for script examples. Joint surface definitions (through stl meshes or direct definition with gts module) are illustrated there.

  property Key

    string specifying the name of saved file ‘cracks___.txt’, when recordCracks is true.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property clusterMoments

    computer clustered moments? (on by default

  property computedCentroid

    computer clustered moments?

  property cracksFileExist

    if true (and if recordCracks), data are appended to an existing ‘cracksKey’ text file; otherwise its content is reset.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property eventNumber

    cluster event number (used for clustering and paraview visualization of groups).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property momentFudgeFactor

    Fudge factor used by Hazzard and Damjanac 2013 to improve moment size accuracy (set to 1 for no impact by default)

  property momentRadiusFactor

    Average particle diameter multiplier for moment magnitude calculation

  property momentsFileExist

    if true (and if recordCracks), data are appended to an existing ‘momentsKey’ text file; otherwise its content is reset.

  property nbShearCracks

    number of shear microcracks.

  property nbTensCracks

    number of tensile microcracks.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene

  property recordCracks

    if true, data about interactions that lose their cohesive feature are stored in the text file cracksKey.txt (see Key and cracksFileExist). It contains 9 columns: the break iteration, the 3 coordinates of the contact point, the type (1 means shear break, while 0 corresponds to tensile break), the ‘’cross section’’ (mean radius of the 2 spheres) and the 3 coordinates of the contact normal.

  property recordMoments

    Combines with :yref: Key<Law2ScGeom_JCFpmPhys_JointedCohesiveFrictionalPM.Key> to compute acoustic emissions according to clustered broken bond method? (off by default)

  property smoothJoint

    if true, interactions of particles belonging to joint surface (JCFpmPhys.isOnJoint) are handled according to a smooth contact logic [Ivars2011], [Scholtes2012].

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property totalCracksSurface

    calculate the total cracked surface.

  property totalShearCracksE

    calculate the overall energy dissipated by interparticle microcracking in shear.

  property totalTensCracksE

    calculate the overall energy dissipated by interparticle microcracking in tension.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property useStrainEnergy

    use strain energy for moment magnitude estimation (if false, use kinetic energy)

class yade.wrapper.Law2_ScGeom_LudingPhys_Basic(inherits LawFunctor → Functor → Serializable)

  Linear viscoelastic model operating on ScGeom and LudingPhys. See [Luding2008] ,[Singh2013]_ for more details.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_MindlinPhysCDM_HertzMindlinCDM(inherits LawFunctor → Functor → Serializable)

  Hertz-Mindlin model extended: Normal direction: conical damage model from Harkness et al. 2016./ Suhr & Six 2017. Tangential direction: stress dependent interparticle friction coefficient, Suhr & Six 2016. Both models can be switched on/off separately. In this version there is NO damping (neither viscous nor linear), NO adhesion and NO calc_energy, NO includeMoment, NO preventGranularRatcheting. NOT tested for periodic simulations.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  ratioSlidingContacts((Law2_ScGeom_MindlinPhysCDM_HertzMindlinCDM)arg1) → float :

    Return the ratio between the number of contacts sliding to the total number at a given time.

  ratioYieldingContacts((Law2_ScGeom_MindlinPhysCDM_HertzMindlinCDM)arg1) → float :

    Return the ratio between the number of contacts yielding to the total number at a given time.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_MindlinPhys_HertzWithLinearShear(inherits LawFunctor → Functor → Serializable)

  Constitutive law for the Hertz formulation (using MindlinPhys.kno) and linear behavior in shear (using MindlinPhys.kso for stiffness and FrictPhys.tangensOfFrictionAngle).

  Note

  No viscosity or damping. If you need those, look at Law2_ScGeom_MindlinPhys_Mindlin, which also includes non-linear Mindlin shear.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property nonLin

    Shear force nonlinearity (the value determines how many features of the non-linearity are taken in account). 1: ks as in HM 2: shearElastic increment computed as in HM 3. granular ratcheting disabled.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_MindlinPhys_Mindlin(inherits LawFunctor → Functor → Serializable)

  Constitutive law for the Hertz-Mindlin formulation. It includes non linear elasticity in the normal direction as predicted by Hertz for two non-conforming elastic contact bodies. In the shear direction, instead, it reseambles the simplified case without slip discussed in Mindlin’s paper, where a linear relationship between shear force and tangential displacement is provided. Finally, the Mohr-Coulomb criterion is employed to established the maximum friction force which can be developed at the contact. Moreover, it is also possible to include the effect of linear viscous damping through the definition of the parameters \(\beta_{n}\) and \(\beta_{s}\).

  property bases

    Ordered list of types (as strings) this functor accepts.

  property calcEnergy

    bool to calculate energy terms (shear potential energy, dissipation of energy due to friction and dissipation of energy due to normal and tangential damping)

  contactsAdhesive((Law2_ScGeom_MindlinPhys_Mindlin)arg1) → float :

    Compute total number of adhesive contacts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property frictionDissipation

    Energy dissipation due to sliding

  property includeAdhesion

    bool to include the adhesion force following the DMT formulation. If true, also the normal elastic energy takes into account the adhesion effect.

  property includeMoment

    bool to consider rolling resistance (if Ip2_FrictMat_FrictMat_MindlinPhys::eta is 0.0, no plastic condition is applied.)

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property normDampDissip

    Energy dissipated by normal damping

  normElastEnergy((Law2_ScGeom_MindlinPhys_Mindlin)arg1) → float :

    Compute normal elastic potential energy. It handles the DMT formulation if Law2_ScGeom_MindlinPhys_Mindlin::includeAdhesion is set to true.

  property nothing

    dummy attribute for declaring preventGranularRatcheting deprecated

  ratioSlidingContacts((Law2_ScGeom_MindlinPhys_Mindlin)arg1) → float :

    Return the ratio between the number of contacts sliding to the total number at a given time.

  property shearDampDissip

    Energy dissipated by tangential damping

  property shearEnergy

    Shear elastic potential energy

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_MindlinPhys_MindlinDeresiewitz(inherits LawFunctor → Functor → Serializable)

  Hertz-Mindlin contact law with partial slip solution, as described in [Thornton1991].

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_MortarPhys_Lourenco(inherits LawFunctor → Functor → Serializable)

  Material law for mortar layer according to [Lourenco1994]. The contact behaves elastic until brittle failure when reaching strength envelope. The envelope has three parts.

  Tensile with condition \(\sigma_N-f_t\).

  Shear part with Mohr-Coulomb condition \(|\sigma_T|+\sigma_N\tan\varphi-c\).

  Compressive part with condition \(\sigma_N^2+A^2\sigma_T^2-f_c^2\)

  The main idea is to begin simulation with this model and when the contact is broken, to use standard non-cohesive Law2_PolyhedraGeom_PolyhedraPhys_Volumetric.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_PotentialLubricationPhys(inherits Law2_ScGeom_ImplicitLubricationPhys → Law2_ScGeom_VirtualLubricationPhys → LawFunctor → Functor → Serializable)

  Material law for lubrication + potential between two spheres. The potential model include contact. This material law will solve the system with lubrication and the provided potential.

  property MaxDist

    Maximum distance (d/a) for the interaction

  property MaxIter

    Maximum iterations for numerical resolution (Dichotomy and Newton-Rafson)

  property SolutionTol

    Tolerance for numerical resolution (Dichotomy and Newton-Rafson)

  property activateRollLubrication

    Activate roll lubrication (default: true)

  property activateTangencialLubrication

    Activate tangencial lubrication (default: true)

  property activateTwistLubrication

    Activate twist lubrication (default: true)

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  static getStressForEachBody() → tuple :

    Get stresses tensors for each bodies: normal contact stress, shear contact stress, normal lubrication stress, shear lubrication stress, stress from additionnal potential forces.

  static getTotalStresses() → tuple :

    Get total stresses tensors: normal contact stress, shear contact stress, normal lubrication stress, shear lubrication stress, stress from additionnal potential forces.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property maxSubSteps

    max recursion depth of adaptative timestepping in the theta-method, the minimal time interval is thus Omega::dt\(/2^{depth}\). If still not converged the integrator will switch to backward Euler.

  property potential

    Physical potential force between spheres.

  property resolution

    Change normal component resolution method, 0: Iterative exact resolution with substepping (theta method, linear contact), 1: Newton-Rafson dimensionless resolution (theta method, linear contact), 2: (default) Dichotomy dimensionless resolution (theta method, linear contact), 3: Exact dimensionless solution with contact prediction (theta method, linear contact). Method 3 is better if the volumic fraction is not too high. Use 2 otherwise.

  property theta

    parameter of the ‘theta’-method, 1: backward Euler, 0.5: trapezoidal rule, 0: not used, 0.55: suggested optimum)

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_VirtualLubricationPhys(inherits LawFunctor → Functor → Serializable)

  Virtual class for sheared lubrication functions. This don’t do any computation and shouldn’t be used directly!

  property MaxDist

    Maximum distance (d/a) for the interaction

  property activateRollLubrication

    Activate roll lubrication (default: true)

  property activateTangencialLubrication

    Activate tangencial lubrication (default: true)

  property activateTwistLubrication

    Activate twist lubrication (default: true)

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  static getStressForEachBody() → tuple :

    Get stresses tensors for each bodies: normal contact stress, shear contact stress, normal lubrication stress, shear lubrication stress, stress from additionnal potential forces.

  static getTotalStresses() → tuple :

    Get total stresses tensors: normal contact stress, shear contact stress, normal lubrication stress, shear lubrication stress, stress from additionnal potential forces.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_ViscElCapPhys_Basic(inherits LawFunctor → Functor → Serializable)

  Extended version of Linear viscoelastic model with capillary parameters.

  property NLiqBridg

    The total number of liquid bridges

  property VLiqBridg

    The total volume of liquid bridges

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_ViscElPhys_Basic(inherits LawFunctor → Functor → Serializable)

  Linear viscoelastic model operating on ScGeom and ViscElPhys. The contact law is visco-elastic in the normal direction, and visco-elastic frictional in the tangential direction. The normal contact is modelled as a spring of equivalent stiffness \(k_n\), placed in parallel with a viscous damper of equivalent viscosity \(c_n\). As for the tangential contact, it is made of a spring-dashpot system (in parallel with equivalent stiffness \(k_s\) and viscosity \(c_s\)) in serie with a slider of friction coefficient \(\mu = \tan \phi\).

  The friction coefficient \(\mu = \tan \phi\) is always evaluated as \(\tan(\min(\phi_1,\phi_2))\), where \(\phi_1\) and \(\phi_2\) are respectively the friction angle of particle 1 and 2. For the other parameters, depending on the material input, the equivalent parameters of the contact (\(K_n\),\(C_n\),\(K_s\),\(C_s\),\(\phi\)) are evaluated differently. In the following, the quantities in parenthesis are the material constant which are precised for each particle. They are then associated to particle 1 and 2 (e.g. \(kn_1\),\(kn_2\),\(cn_1\)…), and should not be confused with the equivalent parameters of the contact (\(K_n\),\(C_n\),\(K_s\),\(C_s\),\(\phi\)).

  > - If contact time (tc), normal and tangential restitution coefficient (en,et) are precised, the equivalent parameters are evaluated following the formulation of Pournin [Pournin2001].

  > - If normal and tangential stiffnesses (kn, ks) and damping constant (cn,cs) of each particle are precised, the equivalent stiffnesses and damping constants of each contact made of two particles 1 and 2 is made \(A = 2\frac{a_1 a_2}{a_1 + a_2}\), where A is \(K_n\), \(K_s\), \(C_n\) and \(C_s\), and 1 and 2 refer to the value associated to particle 1 and 2.

  > - Alternatively it is possible to precise the Young’s modulus (young) and Poisson’s ratio (poisson) instead of the normal and spring constant (kn and ks). In this case, the equivalent parameters are evaluated the same way as the previous case with \(kn_x = E_x d_x\), \(ks_x = v_x kn_x\), where \(E_x\), \(v_x\) and \(d_x\) are Young’s modulus, Poisson’s ratio and diameter of particle x.

  > - If Young’s modulus (young), Poisson’s ratio (poisson), normal and tangential restitution coefficient (en,et) are precised, the equivalent stiffnesses are evaluated as previously: \(K_n = 2\frac{kn_1 kn_2}{kn_1 + kn_2}\), \(kn_x = E_x d_x\), \(K_s = 2(ks_1 ks_2)/(ks_1 + ks_2)\), \(ks_x = v kn_x\). The damping constant is computed at each contact in order to fulfill the normal restitution coefficient \(e_n = (en_1 + en_2)/2\). This is achieved resolving numerically equation 21 of [Schwager2007] (There is in fact a mistake in the article from equation 18 to 19, so that there is a change in sign). Be careful in this configuration the tangential restitution coefficient is set to 1 (no tangential damping). This formulation imposes directly the normal restitution coefficient of the collisions instead of the damping constant.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGeom_ViscoFrictPhys_CundallStrack(inherits Law2_ScGeom_FrictPhys_CundallStrack → LawFunctor → Functor → Serializable)

  Law similar to Law2_ScGeom_FrictPhys_CundallStrack with the addition of shear creep at contacts.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property creepStiffness

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  elasticEnergy((Law2_ScGeom_FrictPhys_CundallStrack)arg1) → float :

    Compute and return the total elastic energy in all “FrictPhys” contacts

  initPlasticDissipation((Law2_ScGeom_FrictPhys_CundallStrack)arg1, (float)arg2) → None :

    Initialize cummulated plastic dissipation to a value (0 by default).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  plasticDissipation((Law2_ScGeom_FrictPhys_CundallStrack)arg1) → float :

    Total energy dissipated in plastic slips at all FrictPhys contacts. Computed only if Law2_ScGeom_FrictPhys_CundallStrack::traceEnergy is true.

  property shearCreep

  property sphericalBodies

    If true, compute branch vectors from radii (faster), else use contactPoint-position. Turning this flag true is safe for sphere-sphere contacts and a few other specific cases. It will give wrong values of torques on facets or boxes.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property traceEnergy

    Define the total energy dissipated in plastic slips at all contacts. This will trace only plastic energy in this law, see O.trackEnergy for a more complete energies tracing

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property viscosity

class yade.wrapper.Law2_ScGeom_WirePhys_WirePM(inherits LawFunctor → Functor → Serializable)

  Constitutive law for the wire model.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property linkThresholdIteration

    Iteration to create the link.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGridCoGeom_CohFrictPhys_CundallStrack(inherits LawFunctor → Functor → Serializable)

  Law between a cohesive frictional GridConnection and a cohesive frictional Sphere. Almost the same than Law2_ScGeom6D_CohFrictPhys_CohesionMoment, but THE ROTATIONAL MOMENTS ARE NOT COMPUTED.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_ScGridCoGeom_FrictPhys_CundallStrack(inherits LawFunctor → Functor → Serializable)

  Law between a frictional GridConnection and a frictional Sphere. Almost the same than Law2_ScGeom_FrictPhys_CundallStrack, but the force is divided and applied on the two GridNodes only.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. Law2_ScGeom_CapillaryPhys_Capillarity)

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Law2_VolumeGeom_FrictPhys_Elastic(inherits LawFunctor → Functor → Serializable)

  Contact law for elasticity, scaling exponentially with the overlap volume, with Mohr-Coulomb plastic failure without cohesion. This law implements a volumetric variant of the classical elastic-plastic law from [CundallStrack1979] (see also [Pfc3dManual30]). The normal force is \(F_n=\min(k_n V_{overlap}^a, 0)\) with \(a=1\) (linear) as the default and the convention of positive tensile forces. The shear force is \(F_s=k_s u_s\), the plasticity condition defines the maximum value of the shear force: \(F_s^{\max}=F_n\tan(\phi)\), with \(\phi\) the friction angle.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  initPlasticDissipation((Law2_VolumeGeom_FrictPhys_Elastic)arg1, (float)arg2) → None :

    Initialize cummulated plastic dissipation to a value (0 by default).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only useful if another contact law is used as well).

  plasticDissipation((Law2_VolumeGeom_FrictPhys_Elastic)arg1) → float :

    Total energy dissipated in plastic slips at all FrictPhys contacts. Computed only if Law2_VolumeGeom_FrictPhys_Elastic::traceEnergy is true.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property traceEnergy

    Define the total energy dissipated in plastic slips at all contacts. This will trace only plastic energy in this law, see O.trackEnergy for a more complete energies tracing.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property volumePower

    The exponent \(a\) on the overlap volume within the contact law. Setting to 0.5 gives a near-linear relationship of force with respect to penetration distance for spheres.

class yade.wrapper.Law2_VolumeGeom_ViscoFrictPhys_Elastic(inherits Law2_VolumeGeom_FrictPhys_Elastic → LawFunctor → Functor → Serializable)

  Law similar to Law2_VolumeGeom_FrictPhys_Elastic with the addition of shear creep at contacts.

  property bases

    Ordered list of types (as strings) this functor accepts.

  property creepStiffness

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  initPlasticDissipation((Law2_VolumeGeom_FrictPhys_Elastic)arg1, (float)arg2) → None :

    Initialize cummulated plastic dissipation to a value (0 by default).

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property neverErase

    Keep interactions even if particles go away from each other (only useful if another contact law is used as well).

  plasticDissipation((Law2_VolumeGeom_FrictPhys_Elastic)arg1) → float :

    Total energy dissipated in plastic slips at all FrictPhys contacts. Computed only if Law2_VolumeGeom_FrictPhys_Elastic::traceEnergy is true.

  property shearCreep

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  property traceEnergy

    Define the total energy dissipated in plastic slips at all contacts. This will trace only plastic energy in this law, see O.trackEnergy for a more complete energies tracing.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property viscosity

  property volumePower

    The exponent \(a\) on the overlap volume within the contact law. Setting to 0.5 gives a near-linear relationship of force with respect to penetration distance for spheres.

### LawDispatcher

class yade.wrapper.LawDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((LawDispatcher)arg1, (IGeom)arg2, (IPhys)arg3) → LawFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((LawDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

## Internal forces

### InternalForceFunctor

Inheritance graph of InternalForceFunctor.

class yade.wrapper.InternalForceFunctor(inherits Functor → Serializable)

  Functor for creating/updating Body::bound.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.If2_2xLin4NodeTetra_LinCohesiveStiffPropDampElastMat(inherits InternalForceFunctor → Functor → Serializable)

  Apply internal forces of the tetrahedral element using lumped mass theory

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.If2_Lin4NodeTetra_LinIsoRayleighDampElast(inherits InternalForceFunctor → Functor → Serializable)

  Apply internal forces of the tetrahedral element using lumped mass theory

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### InternalForceDispatcher

class yade.wrapper.InternalForceDispatcher(inherits Dispatcher → Engine → Serializable)

  Dispatcher calling functors based on received argument type(s).

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dispFunctor((InternalForceDispatcher)arg1, (Shape)arg2, (Material)arg3) → InternalForceFunctor :

    Return functor that would be dispatched for given argument(s); None if no dispatch; ambiguous dispatch throws.

  dispMatrix((InternalForceDispatcher)arg1[, (bool)names=True]) → dict :

    Return dictionary with contents of the dispatch matrix.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property functors

    Functors associated with this dispatcher.

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

## Callbacks

Inheritance graph of IntrCallback.

class yade.wrapper.IntrCallback(inherits Serializable)

  Abstract callback object which will be called for every (real) Interaction after the interaction has been processed by InteractionLoop.

  At the beginning of the interaction loop, `stepInit` is called, initializing the object; it returns either `NULL` (to deactivate the callback during this time step) or pointer to function, which will then be passed (1) pointer to the callback object itself and (2) pointer to Interaction.

  Note

  (NOT YET DONE) This functionality is accessible from python by passing 4th argument to InteractionLoop constructor, or by appending the callback object to InteractionLoop::callbacks.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.SumIntrForcesCb(inherits IntrCallback → Serializable)

  Callback summing magnitudes of forces over all interactions. IPhys of interactions must derive from NormShearPhys (responsability fo the user).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

## Preprocessors

Inheritance graph of FileGenerator.

class yade.wrapper.FileGenerator(inherits Serializable)

  Base class for scene generators, preprocessors.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  generate((FileGenerator)arg1, (str)out) → None :

    Generate scene, save to given file

  load((FileGenerator)arg1) → None :

    Generate scene, save to temporary file and load immediately

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.SimpleShear(inherits FileGenerator → Serializable)

  Preprocessor for a simple shear box model. The packing initially conforms a gas-like, very loose, state (see utils.makeCloud function), but importing some existing packing from a text file can be also performed after little change in the source code. In its current state, the preprocessor carries out an oedometric compression, until a value of normal stress equal to 2 MPa (and a stable mechanical state). Others Engines such as KinemCNDEngine, KinemCNSEngine and KinemCNLEngine, could be used to apply resp. constant normal displacement, constant normal rigidity and constant normal stress paths using such a simple shear box.

  property density

    density of the spheres [\(kg/m^3\)]

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  generate((FileGenerator)arg1, (str)out) → None :

    Generate scene, save to given file

  property gravApplied

    depending on this, GravityEngine is added or not to the scene to take into account the weight of particles

  property gravity

    vector corresponding to used gravity (if gravApplied) [\(m/s^2\)]

  property height

    initial height (along y-axis) of the shear box [\(m\)]

  property length

    initial length (along x-axis) of the shear box [\(m\)]

  load((FileGenerator)arg1) → None :

    Generate scene, save to temporary file and load immediately

  property matFrictionDeg

    value of FrictMat.frictionAngle within the packing and for the two horizontal boundaries (friction is zero along other boundaries) [\(^\circ\)] (the necessary conversion in [\(rad\)] is done automatically)

  property matPoissonRatio

    value of FrictMat.poisson for the bodies [-]

  property matYoungModulus

    value of FrictMat.young for the bodies [\(Pa\)]

  property thickness

    thickness of the boxes constituting the shear box [\(m\)]

  property timeStepUpdateInterval

    value of TimeStepper::timeStepUpdateInterval for the TimeStepper used here

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property width

    initial width (along z-axis) of the shear box [\(m\)]

class yade.wrapper.TriaxialTest(inherits FileGenerator → Serializable)

  Create a scene for triaxal test.

  Introduction

    Yade includes tools to simulate triaxial tests on particles assemblies. This pre-processor (and variants like e.g. CapillaryTriaxialTest) illustrate how to use them. It generates a scene which will - by default - go through the following steps :

    - generate random loose packings in a parallelepiped.

    - compress the packing isotropicaly, either squeezing the packing between moving rigid boxes or expanding the particles while boxes are fixed (depending on flag internalCompaction). The confining pressure in this stage is defined via sigmaIsoCompaction.

    - when the packing is dense and stable, simulate a loading path and get the mechanical response as a result.

    The default loading path corresponds to a constant lateral stress (sigmaLateralConfinement) in 2 directions and constant strain rate on the third direction. This default loading path is performed when the flag autoCompressionActivation it `True`, otherwise the simulation stops after isotropic compression.

    Different loading paths might be performed. In order to define them, the user can modify the flags found in engine TriaxialStressController at any point in the simulation (in c++). If `TriaxialStressController.wall_X_activated` is `true` boundary X is moved automatically to maintain the defined stress level sigmaN (see axis conventions below). If `false` the boundary is not controlled by the engine at all. In that case the user is free to prescribe fixed position, constant velocity, or more complex conditions.

    Note

    Axis conventions. Boundaries perpendicular to the x axis are called “left” and “right”, y corresponds to “top” and “bottom”, and axis z to “front” and “back”. In the default loading path, strain rate is assigned along y, and constant stresses are assigned on x and z.

  Essential engines

    1. The TriaxialCompressionEngine is used for controlling the state of the sample and simulating loading paths. TriaxialCompressionEngine inherits from TriaxialStressController, which computes stress- and strain-like quantities in the packing and maintain a constant level of stress at each boundary. TriaxialCompressionEngine has few more members in order to impose constant strain rate and control the transition between isotropic compression and triaxial test. Transitions are defined by changing some flags of the TriaxialStressController, switching from/to imposed strain rate to/from imposed stress.

    2. The class TriaxialStateRecorder is used to write to a file the history of stresses and strains.

    3. TriaxialTest is using GlobalStiffnessTimeStepper to compute an appropriate \(\Dt\) for the numerical scheme.

    Note

    `TriaxialStressController::ComputeUnbalancedForce` returns a value that can be useful for evaluating the stability of the packing. It is defined as (mean force on particles)/(mean contact force), so that it tends to 0 in a stable packing. This parameter is checked by TriaxialCompressionEngine to switch from one stage of the simulation to the next one (e.g. stop isotropic confinment and start axial loading)

  Frequently Asked Questions

  1. How is generated the packing? How to change particles sizes distribution? Why do I have a message “Exceeded 3000 tries to insert non-overlapping sphere?

       The initial positioning of spheres is done by generating random (x,y,z) in a box and checking if a sphere of radius R (R also randomly generated with respect to a uniform distribution between mean*(1-std_dev) and mean*(1+std_dev) can be inserted at this location without overlaping with others.

       If the sphere overlaps, new (x,y,z)’s are generated until a free position for the new sphere is found. This explains the message you have: after 3000 trial-and-error, the sphere couldn’t be placed, and the algorithm stops.

       You get the message above if you try to generate an initialy dense packing, which is not possible with this algorithm. It can only generate clouds. You should keep the default value of porosity (n~0.7), or even increase if it is still to low in some cases. The dense state will be obtained in the second step (compaction, see below).

  2. How is the compaction done, what are the parameters maxWallVelocity and finalMaxMultiplier?
       Compaction is done

         1. by moving rigid boxes or

         2. by increasing the sizes of the particles (decided using the option internalCompaction ⇒ size increase).

       Both algorithm needs numerical parameters to prevent instabilities. For instance, with the method (1) maxWallVelocity is the maximum wall velocity, with method (2) finalMaxMultiplier is the max value of the multiplier applied on sizes at each iteration (always something like 1.00001).

  3. During the simulation of triaxial compression test, the wall in one direction moves with an increment of strain while the stresses in other two directions are adjusted to sigma_iso. How the stresses in other directions are maintained constant to sigma_iso? What is the mechanism? Where is it implemented in Yade?

       The control of stress on a boundary is based on the total stiffness K of all contacts between the packing and this boundary. In short, at each step, displacement=stress_error/K. This algorithm is implemented in TriaxialStressController, and the control itself is in `TriaxialStressController::ControlExternalStress`. The control can be turned off independently for each boundary, using the flags `wall_XXX_activated`, with XXX∈{top, bottom, left, right, back, front}. The imposed sress is a unique value (sigma_iso) for all directions if TriaxialStressController.isAxisymetric, or 3 independent values sigma1, sigma2, sigma3.

  4. Which value of friction angle do you use during the compaction phase of the Triaxial Test?

       The friction during the compaction (whether you are using the expansion method or the compression one for the specimen generation) can be anything between 0 and the final value used during the Triaxial phase. Note that higher friction than the final one would result in volumetric collapse at the beginning of the test. The purpose of using a different value of friction during this phase is related to the fact that the final porosity you get at the end of the sample generation essentially depends on it as well as on the assumed Particle Size Distribution. Changing the initial value of friction will get to a different value of the final porosity.

  5. Which is the aim of the `bool isRadiusControlIteration`?

       This internal variable (updated automatically) is true each N timesteps (with N=radiusControlInterval). For other timesteps, there is no expansion. Cycling without expanding is just a way to speed up the simulation, based on the idea that 1% increase each 10 iterations needs less operations than 0.1% at each iteration, but will give similar results.

  6. How comes the unbalanced force reaches a low value only after many timesteps in the compaction phase?

       The value of unbalanced force (dimensionless) is expected to reach low value (i.e. identifying a static-equilibrium condition for the specimen) only at the end of the compaction phase. The code is not aiming at simulating a quasistatic isotropic compaction process, it is only giving a stable packing at the end of it.

  property Key

    A code that is added to output filenames.

  property StabilityCriterion

    Value of unbalanced force for which the system is considered stable. Used in conditionals to switch between loading stages.

  property WallStressRecordFile

  property autoCompressionActivation

    Do we just want to generate a stable packing under isotropic pressure (false) or do we want the triaxial loading to start automatically right after compaction stage (true)?

  property autoStopSimulation

    freeze the simulation when conditions are reached (don’t activate this if you want to be able to run/stop from Qt GUI)

  property autoUnload

    auto adjust the isotropic stress state from TriaxialTest::sigmaIsoCompaction to TriaxialTest::sigmaLateralConfinement if they have different values. See docs for TriaxialCompressionEngine::autoUnload

  property boxFrictionDeg

    Friction angle [°] of boundaries contacts.

  property boxKsDivKn

    Ratio of shear vs. normal contact stiffness for boxes.

  property boxYoungModulus

    Stiffness of boxes.

  property compactionFrictionDeg

    Friction angle [°] of spheres during compaction (different values result in different porosities)]. This value is overridden by TriaxialTest::sphereFrictionDeg before triaxial testing.

  property dampingForce

    Coefficient of Cundal-Non-Viscous damping (applied on on the 3 components of forces)

  property dampingMomentum

    Coefficient of Cundal-Non-Viscous damping (applied on on the 3 components of torques)

  property defaultDt

    Max time-step. Used as initial value if defined. Latter adjusted by the time stepper.

  property density

    density of spheres

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property facetWalls

    Use facets for boundaries (not tested)

  property finalMaxMultiplier

    max multiplier of diameters during internal compaction (secondary precise adjustment)

  property fixedBoxDims

    string that contains some subset (max. 2) of {‘x’,’y’,’z’} ; contains axes will have box dimension hardcoded, even if box is scaled as mean_radius is prescribed: scaling will be applied on the rest.

  generate((FileGenerator)arg1, (str)out) → None :

    Generate scene, save to given file

  property importFilename

    File with positions and sizes of spheres.

  property internalCompaction

    flag for choosing between moving boundaries or increasing particles sizes during the compaction stage.

  load((FileGenerator)arg1) → None :

    Generate scene, save to temporary file and load immediately

  property lowerCorner

    Lower corner of the box.

  property maxMultiplier

    max multiplier of diameters during internal compaction (initial fast increase)

  property maxWallVelocity

    max velocity of boundaries. Usually useless, but can help stabilizing the system in some cases.

  property noFiles

    Do not create any files during run (.xml, .spheres, wall stress records)

  property numberOfGrains

    Number of generated spheres.

  property radiusControlInterval

    interval between size changes when growing spheres.

  property radiusMean

    Mean radius. If negative (default), autocomputed to as a function of box size and TriaxialTest::numberOfGrains

  property radiusStdDev

    Normalized standard deviation of generated sizes.

  property recordIntervalIter

    interval between file outputs

  property seed

    Seed used for the call to makeCloud

  property sigmaIsoCompaction

    Confining stress during isotropic compaction (< 0 for real - compressive - compaction).

  property sigmaLateralConfinement

    Lateral stress during triaxial loading (< 0 for classical compressive cases). An isotropic unloading is performed if the value is not equal to TriaxialTest::sigmaIsoCompaction.

  property sphereFrictionDeg

    Friction angle [°] of spheres assigned just before triaxial testing.

  property sphereKsDivKn

    Ratio of shear vs. normal contact stiffness for spheres.

  property sphereYoungModulus

    Stiffness of spheres.

  property strainRate

    Strain rate in triaxial loading.

  property thickness

    thickness of boundaries. It is arbitrary and should have no effect

  property timeStepUpdateInterval

    interval for GlobalStiffnessTimeStepper

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property upperCorner

    Upper corner of the box.

  property wallOversizeFactor

    Make boundaries larger than the packing to make sure spheres don’t go out during deformation.

  property wallStiffnessUpdateInterval

    interval for updating the stiffness of sample/boundaries contacts

  property wallWalls

    Use walls for boundaries (not tested)

## Rendering

### OpenGLRenderer

class yade.wrapper.OpenGLRenderer(inherits Serializable)

  Class responsible for rendering scene on OpenGL devices.

  property bgColor

    Color of the background canvas (RGB)

  property blinkHighlight

    Adjust blinking of the body selected in the ‘Simulation Inspection’ window.

  property bound

    Render body Bound

  property cellColor

    Color of the periodic cell (RGB).

  property clipPlaneActive

    Activate/deactivate respective clipping planes

  property clipPlaneSe3

    Position and orientation of clipping planes

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property dispScale

    Artificially enlarge (scale) dispalcements from bodies’ reference positions by this relative amount, so that they become better visible (independently in 3 dimensions). Disbled if (1,1,1).

  property dof

    Show which degrees of freedom are blocked for each body

  property extraDrawers

    Additional rendering components (GlExtraDrawer).

  property ghosts

    Render objects crossing periodic cell edges by cloning them in multiple places (periodic simulations only).

  hideBody((OpenGLRenderer)arg1, (int)id) → None :

    Hide body from id (see OpenGLRenderer::showBody)

  property id

    Show body id’s

  property intrAllWire

    Draw wire for all interactions, blue for potential and green for real ones (mostly for debugging)

  property intrGeom

    Render Interaction::geom objects.

  property intrPhys

    Render Interaction::phys objects

  property intrWire

    If rendering interactions, use only wires to represent them.

  property light1

    Turn light 1 on.

  property light2

    Turn light 2 on.

  property light2Color

    Per-color intensity of secondary light (RGB).

  property light2Pos

    Position of secondary OpenGL light source in the scene.

  property lightColor

    Per-color intensity of primary light (RGB).

  property lightPos

    Position of OpenGL light source in the scene.

  property mask

    Bitmask for showing only bodies where ((mask & Body::mask)!=0)

  render((OpenGLRenderer)arg1) → None :

    Render the scene in the current OpenGL context.

  property rotScale

    Artificially enlarge (scale) rotations of bodies relative to their reference orientation, so the they are better visible.

  property selId

    Id of particle that was selected by the user.

  setRefSe3((OpenGLRenderer)arg1) → None :

    Make current positions and orientation reference for scaleDisplacements and scaleRotations.

  property shape

    Render body Shape

  showBody((OpenGLRenderer)arg1, (int)id) → None :

    Make body visible (see OpenGLRenderer::hideBody)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property wire

    Render all bodies with wire only (faster)

### GlShapeFunctor

Inheritance graph of GlShapeFunctor.

class yade.wrapper.GlShapeFunctor(inherits Functor → Serializable)

  Abstract functor for rendering Shape objects.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Gl1_Box(inherits GlShapeFunctor → Functor → Serializable)

  Renders Box object

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Gl1_ChainedCylinder(inherits Gl1_Cylinder → GlShapeFunctor → Functor → Serializable)

  Renders ChainedCylinder object including a shift for compensating flexion.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  glutNormalize = True
  glutSlices = 8
  glutStacks = 4
  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  wire = False

class yade.wrapper.Gl1_Cylinder(inherits GlShapeFunctor → Functor → Serializable)

  Renders Cylinder object

  wire(=false) [static]

    Only show wireframe (controlled by `glutSlices` and `glutStacks`.

  glutNormalize(=true) [static]

    Fix normals for non-wire rendering

  glutSlices(=8) [static]

    Number of sphere slices.

  glutStacks(=4) [static]

    Number of sphere stacks.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  glutNormalize = True
  glutSlices = 8
  glutStacks = 4
  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  wire = False

class yade.wrapper.Gl1_DeformableElement(inherits GlShapeFunctor → Functor → Serializable)

  Renders Node object

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Gl1_Facet(inherits GlShapeFunctor → Functor → Serializable)

  Renders Facet object

  normals(=false) [static]

    In wire mode, render normals of facets and edges; facet’s colors are disregarded in that case.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  normals = False
  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Gl1_GridConnection(inherits GlShapeFunctor → Functor → Serializable)

  Renders Cylinder object

  wire(=false) [static]

    Only show wireframe (controlled by `glutSlices` and `glutStacks`.

  glutNormalize(=true) [static]

    Fix normals for non-wire rendering

  glutSlices(=8) [static]

    Number of cylinder slices.

  glutStacks(=4) [static]

    Number of cylinder stacks.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  glutNormalize = True
  glutSlices = 8
  glutStacks = 4
  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  wire = False

class yade.wrapper.Gl1_LevelSet(inherits GlShapeFunctor → Functor → Serializable)

  Renders LevelSet object

  recompute(=false) [static]

    Whether to recompute the triangulation every time it is rendered.

  wire(=false) [static]

    Only show wireframe.

  surfNodes(=false) [static]

    Render surface nodes.

  surface(=true) [static]

    Render particle surface as a zero contour of the distance field using the Marching Cubes algorithm.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  recompute = False
  surfNodes = False
  surface = True
  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  wire = False

class yade.wrapper.Gl1_Node(inherits GlShapeFunctor → Functor → Serializable)

  Renders Node object

  quality(=1.0) [static]

    Change discretization level of spheres. quality>1 for better image quality, at the price of more cpu/gpu usage, 0<quality<1 for faster rendering. If mono-color spheres are displayed (Gl1_Node::stripes = False), quality mutiplies Gl1_Node::glutSlices and Gl1_Node::glutStacks. If striped spheres are displayed (Gl1_Node::stripes = True), only integer increments are meaningfull : quality=1 and quality=1.9 will give the same result, quality=2 will give finer result.

  wire(=false) [static]

    Only show wireframe (controlled by `glutSlices` and `glutStacks`.

  stripes(=false) [static]

    In non-wire rendering, show stripes clearly showing particle rotation.

  localSpecView(=true) [static]

    Compute specular light in local eye coordinate system.

  glutSlices(=12) [static]

    Base number of sphere slices, multiplied by Gl1_Node::quality before use); not used with `stripes` (see glut{Solid,Wire}Sphere reference)

  glutStacks(=6) [static]

    Base number of sphere stacks, multiplied by Gl1_Node::quality before use; not used with `stripes` (see glut{Solid,Wire}Sphere reference)

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  glutSlices = 12
  glutStacks = 6
  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  localSpecView = True
  quality = 1.0
  stripes = False
  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  wire = False

class yade.wrapper.Gl1_PFacet(inherits GlShapeFunctor → Functor → Serializable)

  Renders Facet object

  wire(=false) [static]

    Only show wireframe (controlled by `glutSlices` and `glutStacks`.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  wire = False

class yade.wrapper.Gl1_PotentialParticle(inherits GlShapeFunctor → Functor → Serializable)

  Renders PotentialParticle object

  sizeX(=20) [static]

    Number of divisions in the X direction for triangulation

  sizeY(=20) [static]

    Number of divisions in the Y direction for triangulation

  sizeZ(=20) [static]

    Number of divisions in the Z direction for triangulation

  store(=true) [static]

    Whether to store computed triangulation or not

  initialized(=false) [static]

    Whether the triangulation is initialized

  aabbEnlargeFactor(=1.3) [static]

    Enlargement factor of the Marching Cubes drawing grid, used for displaying purposes. Try different value if the particles are not displayed properly

  wire(=false) [static]

    Only show wireframe

  aabbEnlargeFactor = 1.3
  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  initialized = False
  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  sizeX = 20
  sizeY = 20
  sizeZ = 20
  store = True
  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  wire = False

class yade.wrapper.Gl1_Sphere(inherits GlShapeFunctor → Functor → Serializable)

  Renders Sphere object

  quality(=1.0) [static]

    Change discretization level of spheres. quality>1 for better image quality, at the price of more cpu/gpu usage, 0<quality<1 for faster rendering. If mono-color spheres are displayed (Gl1_Sphere::stripes = False), quality mutiplies Gl1_Sphere::glutSlices and Gl1_Sphere::glutStacks. If striped spheres are displayed (Gl1_Sphere::stripes = True), only integer increments are meaningfull : quality=1 and quality=1.9 will give the same result, quality=2 will give finer result.

  wire(=false) [static]

    Only show wireframe (controlled by `glutSlices` and `glutStacks`.

  stripes(=true) [static]

    In non-wire rendering, show stripes clearly showing particle rotation.

  localSpecView(=true) [static]

    Compute specular light in local eye coordinate system.

  glutSlices(=12) [static]

    Base number of sphere slices, multiplied by Gl1_Sphere::quality before use); not used with `stripes` (see glut{Solid,Wire}Sphere reference)

  glutStacks(=6) [static]

    Base number of sphere stacks, multiplied by Gl1_Sphere::quality before use; not used with `stripes` (see glut{Solid,Wire}Sphere reference)

  circleView(=false) [static]

    For 2D simulations : display tori instead of spheres, so they will appear like circles if the viewer is looking in the right direction. In this case, remember to disable perspective by pressing “t”-key in the viewer.

  circleRelThickness(=0.2) [static]

    If Gl1_Sphere::circleView is enabled, this is the torus diameter relative to the sphere radius (i.e. the circle relative thickness).

  circleAllowedRotationAxis(='z') [static]

    If Gl1_Sphere::circleView is enabled, this is the only axis (‘x’, ‘y’ or ‘z’) along which rotation is allowed for the 2D simulation. It allows right orientation of the tori to appear like circles in the viewer. For example, if circleAllowedRotationAxis=’x’ is set, blockedDOFs=”YZ” should also be set for all your particles.

  property bases

    Ordered list of types (as strings) this functor accepts.

  circleAllowedRotationAxis = 'z'
  circleRelThickness = 0.2
  circleView = False
  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  glutSlices = 12
  glutStacks = 6
  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  localSpecView = True
  quality = 1.0
  stripes = True
  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  wire = False

class yade.wrapper.Gl1_Tetra(inherits GlShapeFunctor → Functor → Serializable)

  Renders Tetra object

  wire(=true) [static]

    TODO

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  wire = True

class yade.wrapper.Gl1_Wall(inherits GlShapeFunctor → Functor → Serializable)

  Renders Wall object

  div(=20) [static]

    Number of divisions of the wall inside visible scene part.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  div = 20
  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### GlStateFunctor

class yade.wrapper.GlStateFunctor(inherits Functor → Serializable)

  Abstract functor for rendering State objects.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### GlBoundFunctor

Inheritance graph of GlBoundFunctor.

class yade.wrapper.GlBoundFunctor(inherits Functor → Serializable)

  Abstract functor for rendering Bound objects.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Gl1_Aabb(inherits GlBoundFunctor → Functor → Serializable)

  Render Axis-aligned bounding box (Aabb).

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### GlIGeomFunctor

Inheritance graph of GlIGeomFunctor.

class yade.wrapper.GlIGeomFunctor(inherits Functor → Serializable)

  Abstract functor for rendering IGeom objects.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Gl1_L3Geom(inherits GlIGeomFunctor → Functor → Serializable)

  Render L3Geom geometry.

  axesLabels(=false) [static]

    Whether to display labels for local axes (x,y,z)

  axesScale(=1.) [static]

    Scale local axes, their reference length being half of the minimum radius.

  axesWd(=1.) [static]

    Width of axes lines, in pixels; not drawn if non-positive

  uPhiWd(=2.) [static]

    Width of lines for drawing displacements (and rotations for L6Geom); not drawn if non-positive.

  uScale(=1.) [static]

    Scale local displacements (u - u0); 1 means the true scale, 0 disables drawing local displacements; negative values are permissible.

  axesLabels = False
  axesScale = 1.0
  axesWd = 1.0
  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  uPhiWd = 2.0
  uScale = 1.0
  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Gl1_L6Geom(inherits Gl1_L3Geom → GlIGeomFunctor → Functor → Serializable)

  Render L6Geom geometry.

  phiScale(=1.) [static]

    Scale local rotations (phi - phi0). The default scale is to draw \(\pi\) rotation with length equal to minimum radius.

  axesLabels = False
  axesScale = 1.0
  axesWd = 1.0
  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  phiScale = 1.0
  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  uPhiWd = 2.0
  uScale = 1.0
  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### GlIPhysFunctor

Inheritance graph of GlIPhysFunctor.

class yade.wrapper.GlIPhysFunctor(inherits Functor → Serializable)

  Abstract functor for rendering IPhys objects.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Gl1_CpmPhys(inherits GlIPhysFunctor → Functor → Serializable)

  Render CpmPhys objects of interactions.

  contactLine(=true) [static]

    Show contact line

  dmgLabel(=true) [static]

    Numerically show contact damage parameter

  dmgPlane(=false) [static]

    [what is this?]

  epsT(=false) [static]

    Show shear strain

  epsTAxes(=false) [static]

    Show axes of shear plane

  normal(=false) [static]

    Show contact normal

  colorStrainRatio(=-1) [static]

    If positive, set the interaction (wire) color based on \(\eps_N\) normalized by \(\eps_0\) x colorStrainRatio (\(\eps_0\) = CpmPhys.epsCrackOnset ). Otherwise, color based on the residual strength.

  epsNLabel(=false) [static]

    Numerically show normal strain

  property bases

    Ordered list of types (as strings) this functor accepts.

  colorStrainRatio = -1.0
  contactLine = True
  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dmgLabel = True
  dmgPlane = False
  epsNLabel = False
  epsT = False
  epsTAxes = False
  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  normal = False
  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Gl1_NormPhys(inherits GlIPhysFunctor → Functor → Serializable)

  Renders NormPhys objects as cylinders of which diameter and color depends on NormPhys.normalForce magnitude.

  maxFn(=0) [static]

    Value of NormPhys.normalForce corresponding to maxRadius. This value will be increased (but not decreased ) automatically.

  signFilter(=0) [static]

    If non-zero, only display contacts with negative (-1) or positive (+1) normal forces; if zero, all contacts will be displayed.

  refRadius(=std::numeric_limits<Real>::infinity()) [static]

    Reference (minimum) particle radius; used only if maxRadius is negative. This value will be decreased (but not increased ) automatically. (auto-updated)

  maxRadius(=-1) [static]

    Cylinder radius corresponding to the maximum normal force. If negative, auto-updated refRadius will be used instead.

  slices(=6) [static]

    Number of sphere slices; (see glutCylinder reference)

  stacks(=1) [static]

    Number of sphere stacks; (see glutCylinder reference)

  maxWeakFn(=NaN) [static]

    Value that divides contacts by their normal force into the ‘weak fabric’ and ‘strong fabric’. This value is set as side-effect by utils.fabricTensor.

  weakFilter(=0) [static]

    If non-zero, only display contacts belonging to the ‘weak’ (-1) or ‘strong’ (+1) fabric.

  weakScale(=1.) [static]

    If maxWeakFn is set, scale radius of the weak fabric by this amount (usually smaller than 1). If zero, 1 pixel line is displayed. Colors are not affected by this value.

  property bases

    Ordered list of types (as strings) this functor accepts.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property label

    Textual label for this object; must be a valid python identifier, you can refer to it directly from python.

  maxFn = 0.0
  maxRadius = -1.0
  maxWeakFn = nan
  refRadius = inf
  signFilter = 0
  slices = 6
  stacks = 1
  property timingDeltas

    Detailed information about timing inside the Dispatcher itself. Empty unless enabled in the source code and O.timingEnabled==True.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  weakFilter = 0
  weakScale = 1.0

## Simulation data

### Omega

class yade.wrapper.Omega

  The whole YADE world made of one or, possibly, several scenes serving as independent simulations. The Omega instance is accessed as O, e.g., O.bodies

  addScene((Omega)arg1) → int :

    Add new scene to Omega, returns its number

  property bodies

    Bodies in the current simulation (container supporting index access by id and iteration)

  bufferFromIntrsct((Omega)arg1, (Subdomain)subdomain, (int)rank, (int)size, (bool)mirror) → object :

    returns a (char*) pointer to the underying buffer of intersections[rank], so that it can be overwritten. Size must be passed in advance. Pointer to mirrorIntersections[rank] is returned if mirror=True. Python syntax: bufferFromIntrsct(…)[:]=bytes(something)

  property cell

    Periodic Cell of the current scene (None if the scene is aperiodic).

  childClassesNonrecursive((Omega)arg1, (str)arg2) → list :

    Return list of all classes deriving from given class, as registered in the class factory

  disableGdb((Omega)arg1) → None :

    Revert SEGV and ABRT handlers to system defaults.

  property dt

    Current timestep (Δt) value. See dynDt for enabling/disabling automatic Δt updates through a TimeStepper.

  property dynDt

    Whether a TimeStepper (when present in O.engines) is used for dynamic Δt control.

  property dynDtAvailable

    Whether a TimeStepper is amongst O.engines, activated or not.

  property energy

    EnergyTracker of the current simulation. (meaningful only with O.trackEnergy)

  property engines

    List of engines in the simulation (corresponds to Scene::engines in C++ source code).

  exitNoBacktrace((Omega)arg1[, (int)status=0]) → None :

    Disable SEGV handler and exit, optionally with given status number.

  property filename

    Filename under which the current simulation was saved (None if never saved).

  property forceSyncCount

    Counter for number of syncs in ForceContainer, for profiling purposes.

  property forces

    ForceContainer (forces, torques) in the current simulation.

  property interactions

    Access to interactions of simulation, by using

    1. id’s of both Bodies of the interactions, e.g. `O.interactions[23,65]`

    2. iteration over the whole container:

           for i in O.interactions: print i.id1,i.id2

    Note

    Iteration silently skips interactions that are not real.

  intrsctToBytes((Omega)arg1, (Subdomain)subdomain, (int)rank, (bool)mirror) → object :

    returns a copy of intersections[rank] (a vector<int>) from a subdomain in the form of bytes. Returns a copy mirrorIntersections[rank] if mirror=True.

  isChildClassOf((Omega)arg1, (str)arg2, (str)arg3) → bool :

    Tells whether the first class derives from the second one (both given as strings).

  property iter

    Get current step number

  labeledEngine((Omega)arg1, (str)arg2) → object :

    Return instance of engine/functor with the given label. This function shouldn’t be called by the user directly; every ehange in O.engines will assign respective global python variables according to labels.

    For example:

    > O.engines=[InsertionSortCollider(label=’collider’)]

    > collider.nBins=5 # collider has become a variable after assignment to O.engines automatically

  load((Omega)arg1, (str)file[, (bool)quiet=False]) → None :

    Load simulation from file. The file should have been saved in the same version of Yade built or compiled with the same features, otherwise compatibility is not guaranteed. Compatibility may also be affected by different versions of external libraries such as Boost

  loadTmp((Omega)arg1[, (str)mark=''[, (bool)quiet=False]]) → None :

    Load simulation previously stored in memory by saveTmp. mark optionally distinguishes multiple saved simulations

  lsTmp((Omega)arg1) → list :

    Return list of all memory-saved simulations.

  property materials

    Shared materials; they can be accessed by id or by label

  property miscParams

    MiscParams in the simulation (Scene::mistParams), usually used to save serializables that don’t fit anywhere else, like GL functors

  property numThreads

    Get maximum number of threads openMP can use.

  pause((Omega)arg1) → None :

    Stop simulation execution. (May be called from within the loop, and it will stop after the current step).

  property periodic

    Get/set whether the current scene is periodic or not (True/False).

  plugins((Omega)arg1) → list :

    Return list of all plugins registered in the class factory.

  property realtime

    Return clock (human world) time the simulation has been running, in seconds.

  reload((Omega)arg1[, (bool)quiet=False]) → None :

    Reload current simulation

  reset((Omega)arg1) → None :

    Reset simulations completely (including another scenes!).

  resetAllScenes((Omega)arg1) → None :

    Reset all scenes.

  resetCurrentScene((Omega)arg1) → None :

    Reset current scene.

  resetThisScene((Omega)arg1) → None :

    Reset current scene.

  resetTime((Omega)arg1) → None :

    Reset simulation time: step number, virtual and real time. (Doesn’t touch anything else, including timings).

  run((Omega)arg1[, (int)nSteps=-1[, (bool)wait=False]]) → None :

    Run the simulation. nSteps how many steps to run, then stop (if positive); wait will cause not returning to python until simulation will have stopped.

  runEngine((Omega)arg1, (Engine)arg2) → None :

    Run given engine exactly once; simulation time, step number etc. will not be incremented (use only if you know what you do).

  property running

    Whether background thread is currently running a simulation.

  save((Omega)arg1, (str)file[, (bool)quiet=False]) → None :

    Save current simulation to file (should be .xml or .xml.bz2 or .yade or .yade.gz). .xml files are bigger than .yade, but can be more or less easily (due to their size) opened and edited, e.g. with text editors. .bz2 and .gz correspond both to compressed versions. There are software requirements for successful reloads, see O.load.

  saveTmp((Omega)arg1[, (str)mark=''[, (bool)quiet=False]]) → None :

    Save simulation to memory (disappears at shutdown), can be loaded later with loadTmp. mark optionally distinguishes different memory-saved simulations.

  sceneToString((Omega)arg1) → object :

    Return the entire scene as a string. Equivalent to using O.save(…) except that the scene goes to a string instead of a file. (see also stringToScene())

  property speed

    Return current calculation speed [iter/sec].

  step((Omega)arg1) → None :

    Advance the simulation by one step. Returns after the step will have finished.

  property stopAtIter

    Get/set number of iteration after which the simulation will stop.

  property stopAtTime

    Get/set time after which the simulation will stop.

  stringToScene((Omega)arg1, (str)arg2[, (str)mark='']) → None :

    Load simulation from a string passed as argument (see also sceneToString).

  property subStep

    Get the current subStep number (only meaningful if O.subStepping==True); -1 when outside the loop, otherwise either 0 (O.subStepping==False) or number of engine to be run (O.subStepping==True)

  property subStepping

    Get/set whether subStepping is active.

  switchScene((Omega)arg1) → None :

    Switch to alternative simulation (while keeping the old one). Calling the function again switches back to the first one. Note that most variables from the first simulation will still refer to the first simulation even after the switch (e.g. b=O.bodies[4]; O.switchScene(); [b still refers to the body in the first simulation here])

  switchToScene((Omega)arg1, (int)arg2) → None :

    Switch to defined scene. Default scene has number 0, other scenes have to be created by addScene method.

  property tags

    Tags (string=string dictionary) of the current simulation (container supporting string-index access/assignment)

  property thisScene

    Return current scene’s id.

  property time

    Return virtual (model world) time of the simulation.

  property timingEnabled

    Globally enable/disable timing services (see documentation of the timing module).

  tmpFilename((Omega)arg1) → str :

    Return unique name of file in temporary directory which will be deleted when yade exits.

  tmpToFile((Omega)arg1, (str)fileName[, (str)mark='']) → None :

    Save XML of saveTmp’d simulation into fileName.

  tmpToString((Omega)arg1[, (str)mark='']) → str :

    Return XML of saveTmp’d simulation as string.

  property trackEnergy

    When energy tracking is enabled or disabled in this simulation.

  wait((Omega)arg1) → None :

    Don’t return until the simulation will have been paused. (Returns immediately if not running).

### BodyContainer

class yade.wrapper.BodyContainer
  __init__((object)arg1, (BodyContainer)arg2) → None
  addToClump((BodyContainer)arg1, (object)arg2, (int)arg3[, (int)discretization=0]) → None :

    Add body b (or a list of bodies) to an existing clump c. c must be clump and b may not be a clump member of c. Clump masses and inertia are adapted automatically (for details see clump()).

    See examples/clumps/addToClump-example.py for an example script.

    Note

    If b is a clump itself, then all members will be added to c and b will be deleted. If b is a clump member of clump d, then all members from d will be added to c and d will be deleted. If you need to add just clump member b, release this member from d first.

  append((BodyContainer)arg1, (Body)arg2) → int :

    Append one Body instance, return its id.

    append( (BodyContainer)arg1, (object)arg2) -> object :

      Append list of Body instance, return list of ids

  appendClumped((BodyContainer)arg1, (object)arg2[, (int)discretization=0]) → tuple :

    Append given list of bodies as a clump (rigid aggregate); returns a tuple of `(clumpId,[memberId1,memberId2,...])`. Clump masses and inertia are computed automatically depending upon discretization (for details see clump()).

  clear((BodyContainer)arg1) → None :

    Remove all bodies (interactions not checked)

  clump((BodyContainer)arg1, (object)arg2[, (int)discretization=0]) → int :

    Clump given bodies together (creating a rigid aggregate); returns `clumpId`. A precise definition of clump masses and inertia when clump members overlap requires spherical members together with discretization>0 and is achieved in this case by integration/summation over mass points using a regular grid of cells (grid cells length is defined as \(L_{min}/discretization\), where \(L_{min}\) is the minimum length of an Axis-Aligned Bounding Box. If *discretization*<=0 sum of inertias from members is simply used, which is faster but accurate only for non-overlapping members).

  deleteClumpBody((BodyContainer)arg1, (Body)arg2) → None :

    Erase clump member.

  deleteClumpMember((BodyContainer)arg1, (Body)arg2, (Body)arg3) → None :

    Erase clump member.

  property enableRedirection

    let collider switch to optimized algorithm with body redirection when bodies are erased - true by default

  erase((BodyContainer)arg1, (int)arg2[, (bool)eraseClumpMembers=0]) → bool :

    Erase body with the given id; all interaction will be deleted by InteractionLoop in the next step. If a clump is erased use O.bodies.erase(clumpId,True) to erase the clump AND its members.

  getRoundness((BodyContainer)arg1[, (list)excludeList=[]]) → float :

    Returns roundness coefficient RC = R2/R1. R1 is the equivalent sphere radius of a clump. R2 is the minimum radius of a sphere, that imbeds the clump. If just spheres are present RC = 1. If clumps are present 0 < RC < 1. Bodies can be excluded from the calculation by giving a list of ids: O.bodies.getRoundness([ids]).

    See examples/clumps/replaceByClumps-example.py for an example script.

  insertAtId((BodyContainer)arg1, (Body)arg2, (int)insertatid) → int :

    Insert a body at theid, (no body should exist in this id)

  releaseFromClump((BodyContainer)arg1, (int)arg2, (int)arg3[, (int)discretization=0]) → None :

    Release body b from clump c. b must be a clump member of c. Clump masses and inertia are adapted automatically (for details see clump()).

    See examples/clumps/releaseFromClump-example.py for an example script.

    Note

    If c contains only 2 members b will not be released and a warning will appear. In this case clump c should be erased.

  replace((BodyContainer)arg1, (object)arg2) → object
  replaceByClumps((BodyContainer)arg1, (list)arg2, (object)arg3[, (int)discretization=0]) → list :

    Replace spheres by clumps using a list of clump templates and a list of amounts; returns a list of tuples: `[(clumpId1,[memberId1,memberId2,...]),(clumpId2,[memberId1,memberId2,...]),...]`. A new clump will have the same volume as the sphere, that was replaced. Clump masses and inertia are adapted automatically (for details see clump()).

    > O.bodies.replaceByClumps( [utils.clumpTemplate([1,1],[.5,.5])] , [.9] ) #will replace 90 % of all standalone spheres by ‘dyads’

    See examples/clumps/replaceByClumps-example.py for an example script.

  subdomainBodies((BodyContainer)arg1) → object :

    id’s of bodies with bounds in MPI subdomain

  updateClumpProperties((BodyContainer)arg1[, (list)excludeList=[][, (int)discretization=5]]) → None :

    Manually force Yade to update clump properties mass, volume and inertia (for details of ‘discretization’ value see clump()). Can be used, when clumps are modified or erased during a simulation. Clumps can be excluded from the calculation by giving a list of ids: O.bodies.updateProperties([ids]).

  property useRedirection

    true if the scene uses up-to-date lists for boundedBodies and realBodies; turned true automatically 1/ after removal of bodies if enableRedirection=True , and 2/ in MPI execution. (auto-updated)

### InteractionContainer

class yade.wrapper.InteractionContainer

  Access to interactions of simulation, by using

  1. id’s of both Bodies of the interactions, e.g. `O.interactions[23,65]`

  2. iteraction over the whole container:

         for i in O.interactions: print i.id1,i.id2

  Note

  Iteration silently skips interactions that are virtual i.e. not real.

  __init__((object)arg1, (InteractionContainer)arg2) → None
  all((InteractionContainer)arg1[, (bool)onlyReal=False]) → list :

    Return list of all interactions. Virtual interaction are filtered out if onlyReal=True, else (default) it dumps the full content.

  clear((InteractionContainer)arg1) → None :

    Remove all interactions, and invalidate persistent collider data (if the collider supports it).

  countReal((InteractionContainer)arg1) → int :

    Return number of interactions that are real.

  erase((InteractionContainer)arg1, (int)arg2, (int)arg3) → None :

    Erase one interaction, given by id1, id2 (internally, `requestErase` is called – the interaction might still exist as potential, if the Collider decides so).

  eraseNonReal((InteractionContainer)arg1) → None :

    Erase all interactions that are not real .

  has((InteractionContainer)arg1, (int)id1, (int)id2[, (bool)onlyReal=False]) → bool :

    Tell if a pair of ids id1, id2 corresponds to an existing interaction (real or not depending on onlyReal)

  nth((InteractionContainer)arg1, (int)arg2) → Interaction :

    Return n-th interaction from the container (usable for picking random interaction). The virtual interactions are not reached.

  property serializeSorted

    None( (yade.wrapper.InteractionContainer)arg1) -> bool

  withBody((InteractionContainer)arg1, (int)arg2) → list :

    Return list of real interactions of given body.

  withBodyAll((InteractionContainer)arg1, (int)arg2) → list :

    Return list of all (real as well as non-real) interactions of given body.

### ForceContainer

class yade.wrapper.ForceContainer
  __init__((object)arg1, (ForceContainer)arg2) → None
  addF((ForceContainer)arg1, (int)id, (yade._minieigenHP.Vector3)f[, (bool)permanent=False]) → None :

    Apply force on body (accumulates). The force applies for one iteration, then it is reset by ForceResetter. # permanent parameter is deprecated, instead of addF(…,permanent=True) use setPermF(…).

  addT((ForceContainer)arg1, (int)id, (yade._minieigenHP.Vector3)t[, (bool)permanent=False]) → None :

    Apply torque on body (accumulates). The torque applies for one iteration, then it is reset by ForceResetter. # permanent parameter is deprecated, instead of addT(…,permanent=True) use setPermT(…).

  f((ForceContainer)arg1, (int)id[, (bool)sync=False]) → yade._minieigenHP.Vector3 :

    Resultant force on body, excluding gravity. For clumps in openMP, synchronize the force container with sync=True, else the value will be wrong.

  getPermForceUsed((ForceContainer)arg1) → bool :

    Check wether permanent forces are present.

  m((ForceContainer)arg1, (int)id[, (bool)sync=False]) → yade._minieigenHP.Vector3 :

    Deprecated alias for t (torque).

  permF((ForceContainer)arg1, (int)id) → yade._minieigenHP.Vector3 :

    read the value of permanent force on body (set with setPermF()).

  permT((ForceContainer)arg1, (int)id) → yade._minieigenHP.Vector3 :

    read the value of permanent torque on body (set with setPermT()).

  reset((ForceContainer)arg1[, (bool)resetAll=True]) → None :

    Reset the force container, including user defined permanent forces/torques. resetAll=False will keep permanent forces/torques unchanged.

  setPermF((ForceContainer)arg1, (int)arg2, (yade._minieigenHP.Vector3)arg3) → None :

    set the value of permanent force on body.

  setPermT((ForceContainer)arg1, (int)arg2, (yade._minieigenHP.Vector3)arg3) → None :

    set the value of permanent torque on body.

  property syncCount

    Number of synchronizations of ForceContainer (cummulative); if significantly higher than number of steps, there might be unnecessary syncs hurting performance.

  t((ForceContainer)arg1, (int)id[, (bool)sync=False]) → yade._minieigenHP.Vector3 :

    Torque applied on body. For clumps in openMP, synchronize the force container with sync=True, else the value will be wrong.

### MaterialContainer

class yade.wrapper.MaterialContainer

  Container for Materials. A material can be accessed using

  1. numerical index in range(0,len(cont)), like cont[2];

  2. textual label that was given to the material, like cont[‘steel’]. This entails traversing all materials and should not be used frequently.

  __init__((object)arg1, (MaterialContainer)arg2) → None
  append((MaterialContainer)arg1, (Material)arg2) → int :

    Add new shared Material; changes its id and return it.

    append( (MaterialContainer)arg1, (object)arg2) -> object :

      Append list of Material instances, return list of ids.

  index((MaterialContainer)arg1, (str)arg2) → int :

    Return id of material, given its label.

### Scene

class yade.wrapper.Scene(inherits Serializable)

  Object comprising a stand-alone simulation.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property doSort

    Used, when new body is added to the scene.

  property dt

    Current timestep for integration.

  property isPeriodic

    Whether periodic boundary conditions are active.

  property iter

    Current iteration (computational step) number

  property selectedBody

    Id of body that is selected by the user

  property speed

    Current calculation speed [iter/s]

  property stopAtIter

    Iteration after which to stop the simulation.

  property stopAtTime

    Time after which to stop the simulation

  property subD

    subdomain (shape) attached to this proc.

  property subStep

    Number of sub-step; not to be changed directly. -1 means to run loop prologue (cell integration), 0…n-1 runs respective engines (n is number of engines), n runs epilogue (increment step number and time.

  property subStepping

    Whether we currently advance by one engine in every step (rather than by single run through all engines).

  property subdomain

    the subdomain this scene is assigned in MPI/domain decomposition.

  property tags

    Arbitrary key=value associations (tags like mp3 tags: author, date, version, description etc.)

  property time

    Simulation time (virtual time) [s]

  property trackEnergy

    Whether energies are being traced.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

### Cell

class yade.wrapper.Cell(inherits Serializable)

  Parameters of periodic boundary conditions. Only applies if O.isPeriodic==True.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  flipCell((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Flip periodic cell so that angles between \(R^3\) axes and transformed axes are as small as possible, using the two following facts:1. repeating in \(R^3\) space the corners of a periodic cell defines a regular grid; 2. two cells leading through this process to a unique grid are equivalent and can be flipped one over another. Flipping includes adjustment of Interaction.cellDist for interactions that cross the boundary and didn’t before (or vice versa), and re-initialization of collider. See also collision detection

  property flipFlippable

    flip automatically as soon as a more compact geometry is possible (see trsf)

  getDefGrad((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns trsf = deformation gradient tensor \(\mat{F}\) of the cell deformation (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getEulerianAlmansiStrain((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns Eulerian-Almansi strain tensor \(\mat{e}=\frac{1}{2}(\mat{I}-\mat{b}^{-1})=\frac{1}{2}(\mat{I}-(\mat{F}\mat{F}^T)^{-1})\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getFluctuationVelocity((Cell)arg1, (Body)b) → yade._minieigenHP.Vector3 :

    get velocity fluctuation of a body, i.e. the velocity relative to mean field velocity: \(\tilde{\vec{v} }= \vec{v} - (\nabla \vec{v}_m)\cdot \vec{x}\)

  getLCauchyGreenDef((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns left Cauchy-Green deformation tensor \(\mat{b}=\mat{F}\mat{F}^T\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getLagrangianStrain((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns Lagrangian strain tensor \(\mat{E}=\frac{1}{2}(\mat{C}-\mat{I})=\frac{1}{2}(\mat{F}^T\mat{F}-\mat{I})=\frac{1}{2}(\mat{U}^2-\mat{I})\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getLeftStretch((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns left (spatial) stretch tensor of the cell (matrix \(\mat{U}\) from polar decomposition \(\mat{F}=\mat{RU}\) )

  getPolarDecOfDefGrad((Cell)arg1) → tuple :

    Returns orthogonal matrix \(\mat{R}\) and symmetric positive semi-definite matrix \(\mat{U}\) as polar decomposition of deformation gradient \(\mat{F}\) of the cell ( \(\mat{F}=\mat{RU}\) )

  getRCauchyGreenDef((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns right Cauchy-Green deformation tensor \(\mat{C}=\mat{F}^T\mat{F}\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getRightStretch((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns right (material) stretch tensor of the cell (matrix \(\mat{V}\) from polar decomposition \(\mat{F}=\mat{RU}=\mat{VR}\ \rightarrow\ \mat{V}=\mat{FR}^T\) )

  getRotation((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns rotation of the cell (orthogonal matrix \(\mat{R}\) from polar decomposition \(\mat{F}=\mat{RU}\) )

  getSmallStrain((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns small strain tensor \(\mat{\varepsilon}=\frac{1}{2}(\mat{F}+\mat{F}^T)-\mat{I}\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getSpin((Cell)arg1) → yade._minieigenHP.Vector3 :

    Returns the spin defined by the skew symmetric part of velGrad

  property hSize

    Base cell vectors (columns of the matrix), updated at every step from velGrad (trsf accumulates applied velGrad transformations). Setting hSize during a simulation is not supported by most contact laws, it is only meant to be used at iteration 0 before any interactions have been created.

  property hSize0

    Value of untransformed hSize with respect to current trsf (computed as trsf ⁻¹ × hSize).

  property homoDeform

    If >0, deform (velGrad) the cell homothetically by adjusting positions and velocities of bodies. The velocity change is obtained by deriving the expression v=∇v.x with respect to time, where ∇v is the macroscopic velocity gradient, giving in an incremental form: Δv=Δ ∇v x + ∇v Δx across one DEM iteration. As a result, velocities are modified as soon as `velGrad` changes, according to the first term: Δv(t)=Δ ∇v x(t), while the 2nd term reflects a convective term: Δv’= ∇v v(t-dt/2). The second term is neglected if homoDeform=1. All terms are included if homoDeform=2 (default)

  property nextVelGrad

    see Cell.velGrad.

  property prevHSize

    hSize from the previous step, used in the definition of relative velocity across periods.

  property prevVelGrad

    Velocity gradient in the previous step.

  property refHSize

    Reference cell configuration, only used with OpenGLRenderer.dispScale. Updated automatically when hSize or trsf is assigned directly; also modified by utils.setRefSe3 (called e.g. by the `Reference` button in the UI).

  property refSize

    Reference size of the cell (lengths of initial cell vectors, i.e. column norms of hSize).

    Note

    Modifying this value is deprecated, use setBox instead.

  setBox((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → None :

    Set Cell shape to be rectangular, with dimensions along axes specified by given argument. Shorthand for assigning diagonal matrix with respective entries to hSize.

    setBox( (Cell)arg1, (float)arg2, (float)arg3, (float)arg4) -> None :

      Set Cell shape to be rectangular, with dimensions along \(x\), \(y\), \(z\) specified by arguments. Shorthand for assigning diagonal matrix with the respective entries to hSize.

  shearPt((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → yade._minieigenHP.Vector3 :

    Apply shear (cell skew+rot) on the point

  property shearTrsf

    Current skew+rot transformation (no resize)

  property size

    Current size of the cell, i.e. lengths of the 3 cell lateral vectors contained in Cell.hSize columns. (auto-updated)

  property trsf

    Current transformation matrix of the cell \(\mat{F}\) giving current Cell vector \(d\vec{x}\) from its reference state \(d\vec{X}\) as per \(d\vec{x} = \mat{F} d\vec{X}\). Obtained from time integration of velGrad\(\times\mat{F}\) as detailed in the documentation during the prologue of a YADE iteration (before the O.engines loop). (auto-updated)

  unshearPt((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → yade._minieigenHP.Vector3 :

    Apply inverse shear on the point (removes skew+rot of the cell)

  property unshearTrsf

    Inverse of the current skew+rot transformation (no resize)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property velGrad

    Velocity gradient of the transformation of the Cell; used in NewtonIntegrator. Values of velGrad accumulate in trsf at every step.

    > note: changing velGrad at the beginning of a timestep would lead to inaccurate integration for that step, as it should normally be changed after the contact laws (but before Newton). To avoid this problem, assignment is deferred automatically. The assigned value is internaly stored in Cell.nextVelGrad and will be applied right in time by Newton integrator.

    Warning

    Assigning individual components as in O.cell.velGrad[0,0]=1 is not possible (it will not return any error but it will have no effect). Instead, the whole matrix should be assigned, as in O.cell.velGrad=Matrix3(…).

  property velGradChanged

    true when velGrad has been changed manually (see also Cell.nextVelGrad)

  property volume

    Current volume of the cell.

  wrap((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → yade._minieigenHP.Vector3 :

    Transform an arbitrary point into a point in the reference cell

  wrapPt((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → yade._minieigenHP.Vector3 :

    Wrap point inside the reference cell, assuming the cell has no skew+rot.

## Other classes

class yade.wrapper.CundallStrackPotential(inherits GenericPotential → Serializable)

  Potential with only Cundall-and-Strack-like contact.

  property alpha

    Bulk-to-roughness stiffness ratio

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.LinExponentialPotential(inherits CundallStrackPotential → GenericPotential → Serializable)

  LinExponential Potential with only Cundall-and-Strack-like contact. The LinExponential potential formula is \(F(u) = \frac{k*(x_e-x_0)}{x_e}(u/a-x_0)\exp\left(\frac{-(u/a)}{x_e-x_0}\right)\). Where \(k\) is the slope at the origin, \(x_0\) is the position where the potential cross \(0\) and \(x_e\) is the position of the extremum.

  property F0

    Force at contact. Force when \(F_0 = F(u=0)\) (LinExponential)

  property Fe

    Extremum force. Value of force at extremum. (LinExponential)

  property alpha

    Bulk-to-roughness stiffness ratio

  computeParametersFromF0((LinExponentialPotential)arg1, (float)F0, (float)xe, (float)k) → None :

    Set parameters of the potential, with \(k\) computed from \(F_0\)

  computeParametersFromF0Fe((LinExponentialPotential)arg1, (float)xe, (float)Fe, (float)F0) → None :

    Set parameters of the potential, with \(k\) and \(x_0\) computed from \(F_0\) and \(F_e\)

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property k

    Slope at the origin (stiffness). (LinExponential)

  potential((LinExponentialPotential)arg1, (float)u) → float :

    Get potential value at any point.

  setParameters((LinExponentialPotential)arg1, (float)x0, (float)xe, (float)k) → None :

    Set parameters of the potential

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property x0

    Equilibrium distance. Potential force is 0 at \(x_0\) (LinExponential)

  property xe

    Extremum position. Position of local max/min of force. (LinExponential)

class yade.wrapper.RegularGrid(inherits Serializable)

  A rectilinear (aka uniform or regular) grid, for LevelSet shapes or other purposes. A cubic regular grid extending from a min = (m,m,m) to a max at (M,M,M), with nGP = (n,n,n) ie a spacing = (M-m)/(n-1), can be conveniently obtained from RegularGrid(m,M,n). For more general cases, minimum point min, spacing and nGP have to be passed as such at instantiation.

  closestCorner((RegularGrid)arg1, (yade._minieigenHP.Vector3)pt[, (bool)unbound=False]) → yade._minieigenHP.Vector3i :

    Returns the Vector3i indices of the closest gridpoint which is smaller (for all components) than pt.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  dims((RegularGrid)arg1) → yade._minieigenHP.Vector3 :

    Returns the grid dimensions along the three axes, as a Vector3.

  gridPoint((RegularGrid)arg1, (int)i, (int)j, (int)k) → yade._minieigenHP.Vector3 :

    Returns the Vector3 position of any grid point, given its indices i (along the X-axis), j (Y-axis), k (Z-axis).

  max((RegularGrid)arg1) → yade._minieigenHP.Vector3 :

    Returns the maximum corner of the grid.

  property min

    The minimum corner of the grid.

  property nGP

    The number of grid points along the three axes as a Vector3i.

  property spacing

    The (uniform and isotropic) grid spacing between two axis-consecutive grid points.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GenericPotential(inherits Serializable)

  Generic class for potential representation in PotentialLubrication law. Don’t do anything. If set as potential, the result will be a lubrication-only simulation.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GlExtra_OctreeCubes(inherits GlExtraDrawer → Serializable)

  Render boxed read from file

  property boxesFile

    File to read boxes from; ascii files with `x0 y0 z0 x1 y1 z1 c` records, where `c` is an integer specifying fill (0 for wire, 1 for filled).

  property dead

    Deactivate the object (on error/exception).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property fillRangeDraw

    Range of fill indices that will be rendered.

  property fillRangeFill

    Range of fill indices that will be filled.

  property levelRangeDraw

    Range of levels that will be rendered.

  property noFillZero

    Do not fill 0-fill boxed (those that are further subdivided)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.MatchMaker(inherits Serializable)

  Class matching pair of ids to return pre-defined (for a pair of ids defined in matches) or derived value (computed using algo) of a scalar parameter. It can be called (`id1`, `id2`, `val1=NaN`, `val2=NaN`) in both python and c++.

  Note

  There is a converter from python number defined for this class, which creates a new MatchMaker returning the value of that number; instead of giving the object instance therefore, you can only pass the number value and it will be converted automatically.

  property algo

    Algorithm used to compute value when no match for ids is found within matches. Possible values are

    - ‘avg’ (arithmetic average)

    - ‘min’ (minimum value)

    - ‘max’ (maximum value)

    - ‘harmAvg’ (harmonic average)

    The other following algo algorithms do not require meaningful input values in order to work:

    - ‘val’ (return value specified by val)

    - ‘zero’ (always return 0.)

  computeFallback((MatchMaker)arg1, (float)val1, (float)val2) → float :

    Compute algo value for val1 and val2, using algorithm specified by algo.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property matches

    Array of `(id1,id2,value)` items; queries matching `id1` + `id2` or `id2` + `id1` will return `value`

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property val

    Constant value returned if there is no match and algo is `val`

class yade.wrapper.Engine(inherits Serializable)

  Basic execution unit of simulation, called from the simulation loop (O.engines)

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GlExtraDrawer(inherits Serializable)

  Performing arbitrary OpenGL drawing commands; called from OpenGLRenderer (see OpenGLRenderer.extraDrawers) once regular rendering routines will have finished.

  This class itself does not render anything, derived classes should override the render method.

  property dead

    Deactivate the object (on error/exception).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.LBMnode(inherits Serializable)

  Node class for Lattice Boltzmann Method

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.MPIBodyContainer(inherits Serializable)

  a dummy container to serialize and send.

  property bContainer

    a dummy body container to serialize

  clearContainer((MPIBodyContainer)arg1) → None :

    clear bodies in the container

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  getCount((MPIBodyContainer)arg1) → int :

    get container count

  insertBody((MPIBodyContainer)arg1, (int)bodyId) → None :

    insert a body (by id) in this container

  insertBodyListPy((MPIBodyContainer)arg1, (list)listOfIds) → None :

    inset a list of bodies (by ids)

  property subdomainRank

    origin rank of this container

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.FastMarchingMethod(inherits Serializable)

  Executes a Fast Marching Method (FMM) to solve \(||\vec \nabla \phi|| = c\) for a discrete field \(\phi\) defined on grid, with phiIni serving as boundary condition. Typically, \(c=1\) (see speed) and \(\phi\) is a distance field. See [Duriez2021b] for more details (where the class was coined DistFMM) and pay attention to heapSort for possibly faster executions.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property grid

    The underlying regular grid.

  property heapSort

    Whether to use a heap-sort (if True) when advancing the narrow band and picking the closest-to-surface gridpoint, for a much faster execution (one or more order of magnitude for significant grid with 1e5 gridpoints or more). Note that the present implementation is not fully bullet-proof in principle for non-convex cases, from the point of view of conserving a heap-structure over the course of all operations, but that no significant consequences of using True have been observed to date.

  property known

    Gridpoints (indices) with distance known for good: they have been at some point the shortest gp to the surface while executing the FMM.

  phi((FastMarchingMethod)arg1) → object :

    Executes the FMM and returns its solution as a list of list of list, with the [i][j][k] element corresponding to grid.gridPoint(i,j,k).

  property phiIni

    Initial discrete field defined on the grid that will serve as a boundary condition for the FMM. Field values have to be - inf (resp. inf) for points being far inside (resp. outside) and correct (finite) on each side of the interface. Built-in functions distIniSE (for superellipsoids), phiIniCppPy (for a Python user function, through a mixed C++-Py internal implementation) or phiIniPy (for a Python user function through a pure Py internal implementation) may be used for such a purpose.

  property speed

    Keep to 1 for a true distance, 2 for the flake-like rose verification of [Duriez2021b].

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.LBMlink(inherits Serializable)

  Link class for Lattice Boltzmann Method

  property DistMid

    Distance between middle of the link and mass center of body

  property PointingOutside

    True if it is a link pointing outside to the system (from a fluid or solid node)

  property VbMid

    Velocity of boundary at midpoint

  property ct

    Coupling term in modified bounce back rule

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property fid

    Fluid node identifier

  property i

    direction index of the link

  property idx_sigma_i

    sigma_i direction index (Fluid->Solid)

  property isBd

    True if it is a boundary link

  property nid1

    fixed node identifier

  property nid2

    fixed node identifier or -1 if node points outside

  property sid

    Solid node identifier

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.ParallelEngine(inherits Engine → Serializable)

  Engine for running other Engine in parallel.

  __init__((object)arg1) → None

    object __init__(tuple args, dict kwds)

    __init__( (object)arg1, (list)arg2) -> object :

      Construct from (possibly nested) list of slaves.

  property dead

    If true, this engine will not run at all; can be used for making an engine temporarily deactivated and only resurrect it at a later point.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property execCount

    Cumulative count this engine was run (only used if O.timingEnabled==`True`).

  property execTime

    Cumulative time in nanoseconds this Engine took to run (only used if O.timingEnabled==`True`).

  property label

    Textual label for this object; must be valid python identifier, you can refer to it directly from python.

  property ompThreads

    Number of threads to be used in the engine. If ompThreads<0 (default), the number will be typically OMP_NUM_THREADS or the number N defined by ‘yade -jN’ (this behavior can depend on the engine though). This attribute will only affect engines whose code includes openMP parallel regions (e.g. InteractionLoop). This attribute is mostly useful for experiments or when combining ParallelEngine with engines that run parallel regions, resulting in nested OMP loops with different number of threads at each level.

  property slaves

    List of lists of Engines; each top-level group will be run in parallel with other groups, while Engines inside each group will be run sequentially, in given order.

  property timingDeltas

    Detailed information about timing inside the Engine itself. Empty unless enabled in the source code and O.timingEnabled==`True`.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Cell(inherits Serializable)

  Parameters of periodic boundary conditions. Only applies if O.isPeriodic==True.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  flipCell((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Flip periodic cell so that angles between \(R^3\) axes and transformed axes are as small as possible, using the two following facts:1. repeating in \(R^3\) space the corners of a periodic cell defines a regular grid; 2. two cells leading through this process to a unique grid are equivalent and can be flipped one over another. Flipping includes adjustment of Interaction.cellDist for interactions that cross the boundary and didn’t before (or vice versa), and re-initialization of collider. See also collision detection

  property flipFlippable

    flip automatically as soon as a more compact geometry is possible (see trsf)

  getDefGrad((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns trsf = deformation gradient tensor \(\mat{F}\) of the cell deformation (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getEulerianAlmansiStrain((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns Eulerian-Almansi strain tensor \(\mat{e}=\frac{1}{2}(\mat{I}-\mat{b}^{-1})=\frac{1}{2}(\mat{I}-(\mat{F}\mat{F}^T)^{-1})\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getFluctuationVelocity((Cell)arg1, (Body)b) → yade._minieigenHP.Vector3 :

    get velocity fluctuation of a body, i.e. the velocity relative to mean field velocity: \(\tilde{\vec{v} }= \vec{v} - (\nabla \vec{v}_m)\cdot \vec{x}\)

  getLCauchyGreenDef((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns left Cauchy-Green deformation tensor \(\mat{b}=\mat{F}\mat{F}^T\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getLagrangianStrain((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns Lagrangian strain tensor \(\mat{E}=\frac{1}{2}(\mat{C}-\mat{I})=\frac{1}{2}(\mat{F}^T\mat{F}-\mat{I})=\frac{1}{2}(\mat{U}^2-\mat{I})\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getLeftStretch((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns left (spatial) stretch tensor of the cell (matrix \(\mat{U}\) from polar decomposition \(\mat{F}=\mat{RU}\) )

  getPolarDecOfDefGrad((Cell)arg1) → tuple :

    Returns orthogonal matrix \(\mat{R}\) and symmetric positive semi-definite matrix \(\mat{U}\) as polar decomposition of deformation gradient \(\mat{F}\) of the cell ( \(\mat{F}=\mat{RU}\) )

  getRCauchyGreenDef((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns right Cauchy-Green deformation tensor \(\mat{C}=\mat{F}^T\mat{F}\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getRightStretch((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns right (material) stretch tensor of the cell (matrix \(\mat{V}\) from polar decomposition \(\mat{F}=\mat{RU}=\mat{VR}\ \rightarrow\ \mat{V}=\mat{FR}^T\) )

  getRotation((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns rotation of the cell (orthogonal matrix \(\mat{R}\) from polar decomposition \(\mat{F}=\mat{RU}\) )

  getSmallStrain((Cell)arg1) → yade._minieigenHP.Matrix3 :

    Returns small strain tensor \(\mat{\varepsilon}=\frac{1}{2}(\mat{F}+\mat{F}^T)-\mat{I}\) of the cell (http://en.wikipedia.org/wiki/Finite_strain_theory)

  getSpin((Cell)arg1) → yade._minieigenHP.Vector3 :

    Returns the spin defined by the skew symmetric part of velGrad

  property hSize

    Base cell vectors (columns of the matrix), updated at every step from velGrad (trsf accumulates applied velGrad transformations). Setting hSize during a simulation is not supported by most contact laws, it is only meant to be used at iteration 0 before any interactions have been created.

  property hSize0

    Value of untransformed hSize with respect to current trsf (computed as trsf ⁻¹ × hSize).

  property homoDeform

    If >0, deform (velGrad) the cell homothetically by adjusting positions and velocities of bodies. The velocity change is obtained by deriving the expression v=∇v.x with respect to time, where ∇v is the macroscopic velocity gradient, giving in an incremental form: Δv=Δ ∇v x + ∇v Δx across one DEM iteration. As a result, velocities are modified as soon as `velGrad` changes, according to the first term: Δv(t)=Δ ∇v x(t), while the 2nd term reflects a convective term: Δv’= ∇v v(t-dt/2). The second term is neglected if homoDeform=1. All terms are included if homoDeform=2 (default)

  property nextVelGrad

    see Cell.velGrad.

  property prevHSize

    hSize from the previous step, used in the definition of relative velocity across periods.

  property prevVelGrad

    Velocity gradient in the previous step.

  property refHSize

    Reference cell configuration, only used with OpenGLRenderer.dispScale. Updated automatically when hSize or trsf is assigned directly; also modified by utils.setRefSe3 (called e.g. by the `Reference` button in the UI).

  property refSize

    Reference size of the cell (lengths of initial cell vectors, i.e. column norms of hSize).

    Note

    Modifying this value is deprecated, use setBox instead.

  setBox((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → None :

    Set Cell shape to be rectangular, with dimensions along axes specified by given argument. Shorthand for assigning diagonal matrix with respective entries to hSize.

    setBox( (Cell)arg1, (float)arg2, (float)arg3, (float)arg4) -> None :

      Set Cell shape to be rectangular, with dimensions along \(x\), \(y\), \(z\) specified by arguments. Shorthand for assigning diagonal matrix with the respective entries to hSize.

  shearPt((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → yade._minieigenHP.Vector3 :

    Apply shear (cell skew+rot) on the point

  property shearTrsf

    Current skew+rot transformation (no resize)

  property size

    Current size of the cell, i.e. lengths of the 3 cell lateral vectors contained in Cell.hSize columns. (auto-updated)

  property trsf

    Current transformation matrix of the cell \(\mat{F}\) giving current Cell vector \(d\vec{x}\) from its reference state \(d\vec{X}\) as per \(d\vec{x} = \mat{F} d\vec{X}\). Obtained from time integration of velGrad\(\times\mat{F}\) as detailed in the documentation during the prologue of a YADE iteration (before the O.engines loop). (auto-updated)

  unshearPt((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → yade._minieigenHP.Vector3 :

    Apply inverse shear on the point (removes skew+rot of the cell)

  property unshearTrsf

    Inverse of the current skew+rot transformation (no resize)

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property velGrad

    Velocity gradient of the transformation of the Cell; used in NewtonIntegrator. Values of velGrad accumulate in trsf at every step.

    > note: changing velGrad at the beginning of a timestep would lead to inaccurate integration for that step, as it should normally be changed after the contact laws (but before Newton). To avoid this problem, assignment is deferred automatically. The assigned value is internaly stored in Cell.nextVelGrad and will be applied right in time by Newton integrator.

    Warning

    Assigning individual components as in O.cell.velGrad[0,0]=1 is not possible (it will not return any error but it will have no effect). Instead, the whole matrix should be assigned, as in O.cell.velGrad=Matrix3(…).

  property velGradChanged

    true when velGrad has been changed manually (see also Cell.nextVelGrad)

  property volume

    Current volume of the cell.

  wrap((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → yade._minieigenHP.Vector3 :

    Transform an arbitrary point into a point in the reference cell

  wrapPt((Cell)arg1, (yade._minieigenHP.Vector3)arg2) → yade._minieigenHP.Vector3 :

    Wrap point inside the reference cell, assuming the cell has no skew+rot.

class yade.wrapper.EnergyTracker(inherits Serializable)

  Storage for tracing energies. Only to be used if O.trackEnergy is True.

  clear((EnergyTracker)arg1) → None :

    Clear all stored values.

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property energies

    Energy values, in linear array

  items((EnergyTracker)arg1) → list :

    Return contents as list of (name,value) tuples.

  keys((EnergyTracker)arg1) → list :

    Return defined energies.

  total((EnergyTracker)arg1) → float :

    Return sum of all energies.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.Serializable
  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.LBMbody(inherits Serializable)

  Body class for Lattice Boltzmann Method

  property AVel

    Angular velocity of body

  property Fh

    Hydrodynamical force on body

  property Mh

    Hydrodynamical momentum on body

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property fm

    Hydrodynamic force (LB unit) at t-0.5dt

  property force

    Hydrodynamic force, need to be reinitialized (LB unit)

  property fp

    Hydrodynamic force (LB unit) at t+0.5dt

  property isEroded

    Hydrodynamical force on body

  property mm

    Hydrodynamic momentum (LB unit) at t-0.5dt

  property momentum

    Hydrodynamic momentum,need to be reinitialized (LB unit)

  property mp

    Hydrodynamic momentum (LB unit) at t+0.5dt

  property pos

    Position of body

  property radius

    Radius of body (for sphere)

  property saveProperties

    To save properties of the body

  property type

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

  property vel

    Velocity of body

class yade.wrapper.CundallStrackAdhesivePotential(inherits CundallStrackPotential → GenericPotential → Serializable)

  CundallStrack model with adhesive part. Contact is created when \(u/a-\varepsilon < 0\) and released when \(u/a-\varepsilon > l_{adh}\), where \(l_{adh} = f_{adh}/k_n\). This lead to an hysteretic attractive part.

  property alpha

    Bulk-to-roughness stiffness ratio

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property fadh

    Adhesion force.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.GlExtra_LawTester(inherits GlExtraDrawer → Serializable)

  Find an instance of LawTester and show visually its data.

  property dead

    Deactivate the object (on error/exception).

  dict((Serializable)arg1) → dict :

    Return dictionary of attributes.

  property tester

    Associated LawTester object.

  updateAttrs((Serializable)arg1, (dict)arg2) → None :

    Update object attributes from given dictionary

class yade.wrapper.TimingDeltas
  property data

    Get timing data as list of tuples (label, execTime[nsec], execCount) (one tuple per checkpoint)

  reset((TimingDeltas)arg1) → None :

    Reset timing information