Compilation instructions

- 1 Quickstart
- 2 Detailed configuration and compilation
  - 2.1 Mandatory dependencies
    - 2.1.1 The GNU Scientific Library
  - 2.2 Optional dependencies
    - 2.2.1 SUNDIALS
    - 2.2.2 PETSc
    - 2.2.3 SLEPc
  - 2.3 FeenoX source code
    - 2.3.1 Git repository
    - 2.3.2 Source tarballs
  - 2.4 Configuration
  - 2.5 Source code compilation
  - 2.6 Test suite
  - 2.7 Installation
- 3 Advanced settings
  - 3.1 Compiling with debug symbols
  - 3.2 Using a different compiler
  - 3.3 Compiling PETSc

These detailed compilation instructions are aimed at amd64 Debian-based
GNU/Linux distributions. The compilation procedure follows the POSIX
standard, so it should work in other operating systems and architectures
as well. Distributions not using apt for packages (i.e. yum) should
change the package installation commands (and possibly the package
names). The instructions should also work for in MacOS, although the
apt-get commands should be replaced by brew or similar. Same for Windows
under Cygwin, the packages should be installed through the Cygwin
installer. WSL was not tested, but should work as well.

  [1 Quickstart]: #quickstart
  [2 Detailed configuration and compilation]: #sec:details
  [2.1 Mandatory dependencies]: #mandatory-dependencies
  [2.1.1 The GNU Scientific Library]: #sec:gsl
  [2.2 Optional dependencies]: #optional-dependencies
  [2.2.1 SUNDIALS]: #sundials
  [2.2.2 PETSc]: #petsc
  [2.2.3 SLEPc]: #slepc
  [2.3 FeenoX source code]: #feenox-source-code
  [2.3.1 Git repository]: #git-repository
  [2.3.2 Source tarballs]: #source-tarballs
  [2.4 Configuration]: #configuration
  [2.5 Source code compilation]: #sec:compilation
  [2.6 Test suite]: #sec:test-suite
  [2.7 Installation]: #installation
  [3 Advanced settings]: #advanced-settings
  [3.1 Compiling with debug symbols]: #compiling-with-debug-symbols
  [3.2 Using a different compiler]: #using-a-different-compiler
  [3.3 Compiling PETSc]: #compiling-petsc
  [POSIX standard]: https://en.wikipedia.org/wiki/POSIX
  [Cygwin]: https://www.cygwin.com/

Quickstart

Note that the quickest way to get started is to download an
already-compiled statically-linked binary executable. Note that getting
a binary is the quickest and easiest way to go but it is the less
flexible one. Mind the following instructions if a binary-only option is
not suitable for your workflow and/or you do need to compile the source
code from scratch.

On a GNU/Linux box (preferably Debian-based), follow these quick steps.
See sec. 2 for the actual detailed explanations.

The Git repository has the latest sources repository. To compile,
proceed as follows. If something goes wrong and you get an error, do not
hesitate to ask in FeenoX’s discussion page.

  If you do not have Git or Autotools, download a source tarball and
  proceed with the usual configure & make procedure. See these
  instructions.

1.  Install mandatory dependencies

        sudo apt-get update
        sudo apt-get install git build-essential make automake autoconf libgsl-dev

    If you cannot install libgsl-dev but still have git and the build
    toolchain, you can have the configure script to download and compile
    it for you. See point 4 below.

2.  Install optional dependencies (of course these are optional but
    recommended)

        sudo apt-get install libsundials-dev petsc-dev slepc-dev

3.  Clone Github repository

        git clone https://github.com/seamplex/feenox

4.  Bootstrap, configure, compile & make

        cd feenox
        ./autogen.sh
        ./configure
        make -j4

    If you cannot (or do not want to) use libgsl-dev from a package
    repository, call configure with --enable-download-gsl:

        ./configure --enable-download-gsl

    If you do not have Internet access, get the tarball manually, copy
    it to the same directory as configure and run again. See the
    detailed compilation instructions for an explanation.

5.  Run test suite (optional)

        make check

6.  Install the binary system wide (optional)

        sudo make install

      If you do not have root permissions, configure with your home
      directory as prefix and then make install as a regular user:

          ./configure --prefix=$HOME
          make
          make install

To stay up to date, pull and then autogen, configure and make (and
optionally install):

    git pull
    ./autogen.sh
    ./configure
    make -j4
    sudo make install

  [download]: https://www.seamplex.com/feenox/#download
  [discussion page]: https://github.com/seamplex/feenox/discussions
  [source tarball]: https://seamplex.com/feenox/dist/src/
  [these instructions]: doc/source.md
  [detailed compilation instructions]: compilation.md

Detailed configuration and compilation

The main target and development environment is Debian GNU/Linux,
although it should be possible to compile FeenoX in any free GNU/Linux
variant (and even the in non-free MacOS and/or Windows platforms)
running in virtually any hardware platform. FeenoX can run be run either
in HPC cloud servers or a Raspberry Pi, and almost everything that sits
in the middle.

Following the Unix philosophy discussed in the SDS, FeenoX re-uses a lot
of already-existing high-quality free and open source libraries that
implement a wide variety of mathematical operations. This leads to a
number of dependencies that FeenoX needs in order to implement certain
features.

There is only one dependency that is mandatory, namely GNU GSL
(see sec. 2.1.1), which if it not found then FeenoX cannot be compiled.
All other dependencies are optional, meaning that FeenoX can be compiled
but its capabilities will be partially reduced.

As per the SRS, all dependencies have to be available on mainstream
GNU/Linux distributions and have to be free and open source software.
But they can also be compiled from source in case the package
repositories are not available or customized compilation flags are
needed (i.e. optimization or debugging settings).

In particular, PETSc (and SLEPc) also depend on other mathematical
libraries to perform particular operations such as low-level linear
algebra operations. These extra dependencies can be either free (such as
LAPACK) or non-free (such as Intel’s MKL), but there is always at least
one combination of a working setup that involves only free and open
source software which is compatible with FeenoX licensing terms
(GPLv3+). See the documentation of each package for licensing details.

  [Debian GNU/Linux]: https://www.debian.org/
  [SDS]: SDS.md
  [GNU GSL]: https://www.gnu.org/software/gsl/
  [SRS]: SRS.md
  [PETSc]: https://petsc.org/release/
  [SLEPc]: https://slepc.upv.es/
  [LAPACK]: http://www.netlib.org/lapack/
  [Intel’s MKL]: https://www.intel.com/content/www/us/en/developer/tools/oneapi/onemkl.html

Mandatory dependencies

FeenoX has one mandatory dependency for run-time execution and the
standard build toolchain for compilation. It is written in C99 so only a
C compiler is needed, although make is also required. Free and open
source compilers are favored. The usual C compiler is gcc but clang or
Intel’s icc and the newer icx can also be used.

Note that there is no need to have a Fortran nor a C++ compiler to build
FeenoX. They might be needed to build other dependencies (such as PETSc
and its dependencies), but not to compile FeenoX if all the dependencies
are installed from the operating system’s package repositories. In case
the build toolchain is not already installed, do so with

    sudo apt-get install gcc make

If the source is to be fetched from the Git repository then not only is
git needed but also autoconf and automake since the configure script is
not stored in the Git repository but the autogen.sh script that
bootstraps the tree and creates it. So if instead of compiling a source
tarball one wants to clone from GitHub, these packages are also
mandatory:

    sudo apt-get install git automake autoconf

Again, chances are that any existing GNU/Linux box has all these tools
already installed.

  [Git repository]: https://github.com/seamplex/feenox/

The GNU Scientific Library

The only run-time dependency is GNU GSL (not to be confused with
Microsoft GSL). It can be installed with

    sudo apt-get install libgsl-dev

In case this package is not available or you do not have enough
permissions to install system-wide packages, there are two options.

1.  Pass the option --enable-download-gsl to the configure script below.
2.  Manually download, compile and install GNU GSL

If the configure script cannot find both the headers and the actual
library, it will refuse to proceed. Note that the FeenoX binaries
already contain a static version of the GSL so it is not needed to have
it installed in order to run the statically-linked binaries.

  [GNU GSL]: https://www.gnu.org/software/gsl/
  [Microsoft GSL]: https://github.com/microsoft/GSL

Optional dependencies

FeenoX has three optional run-time dependencies. It can be compiled
without any of these, but functionality will be reduced:

- SUNDIALS provides support for solving systems of ordinary differential
  equations (ODEs) or differential-algebraic equations (DAEs). This
  dependency is needed when running inputs with the PHASE_SPACE keyword.

- PETSc provides support for solving partial differential equations
  (PDEs). This dependency is needed when running inputs with the PROBLEM
  keyword.

- SLEPc provides support for solving eigen-value problems in partial
  differential equations (PDEs). This dependency is needed for inputs
  with PROBLEM types with eigen-value formulations such as modal and
  neutron_sn.

In absence of all these, FeenoX can still be used to

- solve general mathematical problems such as the ones to compute the
  Fibonacci sequence or the Logistic map,
- operate on functions, either algebraically or point-wise interpolated
  such as Computing the derivative of a function as a Unix filter
- read, operate over and write meshes,
- etc.

These optional dependencies have to be installed separately. There is no
option to have configure to download them as with --enable-download-gsl.
When running the test suite (sec. 2.6), those tests that need an
optional dependency which was not found at compile time will be skipped.

  [SUNDIALS]: https://computing.llnl.gov/projects/sundials
  [1]: https://petsc.org/
  [SLEPc]: https://slepc.upv.es/
  [Fibonacci sequence]: https://www.seamplex.com/feenox/examples/#the-fibonacci-sequence
  [Logistic map]: https://www.seamplex.com/feenox/examples/#the-logistic-map
  [Computing the derivative of a function as a Unix filter]: https://www.seamplex.com/feenox/examples/#computing-the-derivative-of-a-function-as-a-unix-filter

SUNDIALS

SUNDIALS is a SUite of Nonlinear and DIfferential/ALgebraic equation
Solvers. It is used by FeenoX to solve dynamical systems casted as DAEs
with the keyword PHASE_SPACE, like the Lorenz system.

Install either by doing

    sudo apt-get install libsundials-dev

or by following the instructions in the documentation.

  [SUNDIALS]: https://computing.llnl.gov/projects/sundials
  [PHASE_SPACE]: https://www.seamplex.com/feenox/doc/feenox-manual.html#phase_space
  [the Lorenz system]: https://www.seamplex.com/feenox/examples/#lorenz-attractor-the-one-with-the-butterfly

PETSc

The Portable, Extensible Toolkit for Scientific Computation, pronounced
PET-see (/ˈpɛt-siː/), is a suite of data structures and routines for the
scalable (parallel) solution of scientific applications modeled by
partial differential equations. It is used by FeenoX to solve PDEs with
the keyword PROBLEM, like the NAFEMS LE10 benchmark problem.

Install either by doing

    sudo apt-get install petsc-dev

or by following the instructions in the documentation.

Note that

- Configuring and compiling PETSc from scratch might be difficult the
  first time. It has a lot of dependencies and options. Read the
  official documentation for a detailed explanation.
- There is a huge difference in efficiency between using PETSc compiled
  with debugging symbols and with optimization flags. Make sure to
  configure --with-debugging=0 for FeenoX production runs and leave the
  debugging symbols (which is the default) for development and debugging
  only.
- FeenoX needs PETSc to be configured with real double-precision
  scalars. It will compile but will complain at run-time when using
  complex and/or single or quad-precision scalars.
- FeenoX honors the PETSC_DIR and PETSC_ARCH environment variables when
  executing configure. If these two do not exist or are empty, it will
  try to use the default system-wide locations (i.e. the petsc-dev
  package).

  [Portable, Extensible Toolkit for Scientific Computation]: (https://petsc.org/)
  [PROBLEM]: https://www.seamplex.com/feenox/doc/feenox-manual.html#problem
  [NAFEMS LE10 benchmark problem]: https://www.seamplex.com/feenox/examples/#nafems-le10-thick-plate-pressure-benchmark
  [documentation]: https://petsc.org/release/install/

SLEPc

The Scalable Library for Eigenvalue Problem Computations, is a software
library for the solution of large scale sparse eigenvalue problems on
parallel computers. It is used by FeenoX to solve PDEs with the keyword
PROBLEM that need eigen-value computations, such as modal analysis of a
cantilevered beam.

Install either by doing

    sudo apt-get install slepc-dev

or by following the instructions in the documentation.

Note that

- SLEPc is an extension of PETSc so the latter has to be already
  installed and configured.
- FeenoX honors the SLEPC_DIR environment variable when executing
  configure. If it does not exist or is empty it will try to use the
  default system-wide locations (i.e. the slepc-dev package).
- If PETSc was configured with --download-slepc then the SLEPC_DIR
  variable has to be set to the directory inside PETSC_DIR where SLEPc
  was cloned and compiled.

  [Scalable Library for Eigenvalue Problem Computations]: https://slepc.upv.es/
  [PROBLEM]: https://www.seamplex.com/feenox/doc/feenox-manual.html#problem
  [modal analysis of a cantilevered beam]: https://www.seamplex.com/feenox/examples/#five-natural-modes-of-a-cantilevered-wire

FeenoX source code

There are two ways of getting FeenoX’s source code:

1.  Cloning the GitHub repository at https://github.com/seamplex/feenox
2.  Downloading a source tarball from
    https://seamplex.com/feenox/dist/src/

Git repository

The main Git repository is hosted on GitHub at
https://github.com/seamplex/feenox. It is public so it can be cloned
either through HTTPS or SSH without needing any particular credentials.
It can also be forked freely. See the Programming Guide for details
about pull requests and/or write access to the main repository.

Ideally, the main branch should have a usable snapshot. All other
branches can contain code that might not compile or might not run or
might not be tested. If you find a commit in the main branch that does
not pass the tests, please report it in the issue tracker ASAP.

After cloning the repository

    git clone https://github.com/seamplex/feenox

the autogen.sh script has to be called to bootstrap the working tree,
since the configure script is not stored in the repository but created
from configure.ac (which is in the repository) by autogen.sh.

Similarly, after updating the working tree with

    git pull

it is recommended to re-run the autogen.sh script. It will do a
make clean and re-compute the version string.

  [Programming Guide]: programming.md

Source tarballs

When downloading a source tarball, there is no need to run autogen.sh
since the configure script is already included in the tarball. This
method cannot update the working tree. For each new FeenoX release, the
whole source tarball has to be downloaded again.

Configuration

To create a proper Makefile for the particular architecture,
dependencies and compilation options, the script configure has to be
executed. This procedure follows the GNU Coding Standards.

    ./configure

Without any particular options, configure will check if the mandatory
GNU Scientific Library is available (both its headers and run-time
library). If it is not, then the option --enable-download-gsl can be
used. This option will try to use wget (which should be installed) to
download a source tarball, uncompress, configure and compile it. If
these steps are successful, this GSL will be statically linked into the
resulting FeenoX executable. If there is no internet connection, the
configure script will say that the download failed. In that case, get
the indicated tarball file manually, copy it into the current directory
and re-run ./configure.

The script will also check for the availability of optional
dependencies. At the end of the execution, a summary of what was found
(or not) is printed in the standard output:

    $ ./configure
    [...]
    ## ----------------------- ##
    ## Summary of dependencies ##
    ## ----------------------- ##
      GNU Scientific Library  from system
      SUNDIALS IDA            yes
      PETSc                   yes /usr/lib/petsc 
      SLEPc                   no
    [...]  

If for some reason one of the optional dependencies is available but
FeenoX should not use it, then pass --without-sundials, --without-petsc
and/or --without-slepc as arguments. For example

    $ ./configure --without-sundials --without-petsc
    [...]
    ## ----------------------- ##
    ## Summary of dependencies ##
    ## ----------------------- ##
      GNU Scientific Library  from system
      SUNDIALS                no
      PETSc                   no
      SLEPc                   no
    [...]  

If configure complains about contradicting values from the cached ones,
run autogen.sh again before configure and/or clone/uncompress the source
tarball in a fresh location.

To see all the available options run

    ./configure --help

  [GNU Coding Standards]: https://www.gnu.org/prep/standards/
  [GNU Scientific Library]: https://www.gnu.org/software/gsl/

Source code compilation

After the successful execution of configure, a Makefile is created. To
compile FeenoX, just execute

    make

Compilation should take a dozen of seconds. It can be even sped up by
using the -j option

    make -j8

The binary executable will be located in the src directory but a copy
will be made in the base directory as well. Test it by running without
any arguments

    $ ./feenox
    FeenoX v0.2.14-gbbf48c9
    a free no-fee no-X uniX-like finite-element(ish) computational engineering tool

    usage: feenox [options] inputfile [replacement arguments] [petsc options]

      -h, --help         display options and detailed explanations of command-line usage
      -v, --version      display brief version information and exit
      -V, --versions     display detailed version information

    Run with --help for further explanations.
    $

The -v (or --version) option shows the version and a copyright notice:

    $ ./feenox -v
    FeenoX v0.2.14-gbbf48c9
    a free no-fee no-X uniX-like finite-element(ish) computational engineering tool

    Copyright © 2009--2022 https://seamplex.com/feenox
    GNU General Public License v3+, https://www.gnu.org/licenses/gpl.html. 
    FeenoX is free software: you are free to change and redistribute it.
    There is NO WARRANTY, to the extent permitted by law.
    $

The -V (or --versions) option shows the dates of the last commits, the
compiler options and the versions of the linked libraries:

    $ ./feenox -V
    FeenoX v0.1.24-g6cfe063
    a free no-fee no-X uniX-like finite-element(ish) computational engineering tool

    Last commit date   : Sun Aug 29 11:34:04 2021 -0300
    Build date         : Sun Aug 29 11:44:50 2021 -0300
    Build architecture : linux-gnu x86_64
    Compiler version   : gcc (Debian 10.2.1-6) 10.2.1 20210110
    Compiler expansion : gcc -Wl,-z,relro -I/usr/include/x86_64-linux-gnu/mpich -L/usr/lib/x86_64-linux-gnu -lmpich
    Compiler flags     : -O3
    Builder            : gtheler@chalmers
    GSL version        : 2.6
    SUNDIALS version   : 4.1.0
    PETSc version      : Petsc Release Version 3.14.5, Mar 03, 2021 
    PETSc arch         : 
    PETSc options      : --build=x86_64-linux-gnu --prefix=/usr --includedir=${prefix}/include --mandir=${prefix}/share/man --infodir=${prefix}/share/info --sysconfdir=/etc --localstatedir=/var --with-option-checking=0 --with-silent-rules=0 --libdir=${prefix}/lib/x86_64-linux-gnu --runstatedir=/run --with-maintainer-mode=0 --with-dependency-tracking=0 --with-debugging=0 --shared-library-extension=_real --with-shared-libraries --with-pic=1 --with-cc=mpicc --with-cxx=mpicxx --with-fc=mpif90 --with-cxx-dialect=C++11 --with-opencl=1 --with-blas-lib=-lblas --with-lapack-lib=-llapack --with-scalapack=1 --with-scalapack-lib=-lscalapack-openmpi --with-ptscotch=1 --with-ptscotch-include=/usr/include/scotch --with-ptscotch-lib="-lptesmumps -lptscotch -lptscotcherr" --with-fftw=1 --with-fftw-include="[]" --with-fftw-lib="-lfftw3 -lfftw3_mpi" --with-superlu_dist=1 --with-superlu_dist-include=/usr/include/superlu-dist --with-superlu_dist-lib=-lsuperlu_dist --with-hdf5-include=/usr/include/hdf5/openmpi --with-hdf5-lib="-L/usr/lib/x86_64-linux-gnu/hdf5/openmpi -L/usr/lib/x86_64-linux-gnu/openmpi/lib -lhdf5 -lmpi" --CXX_LINKER_FLAGS=-Wl,--no-as-needed --with-hypre=1 --with-hypre-include=/usr/include/hypre --with-hypre-lib=-lHYPRE_core --with-mumps=1 --with-mumps-include="[]" --with-mumps-lib="-ldmumps -lzmumps -lsmumps -lcmumps -lmumps_common -lpord" --with-suitesparse=1 --with-suitesparse-include=/usr/include/suitesparse --with-suitesparse-lib="-lumfpack -lamd -lcholmod -lklu" --with-superlu=1 --with-superlu-include=/usr/include/superlu --with-superlu-lib=-lsuperlu --prefix=/usr/lib/petscdir/petsc3.14/x86_64-linux-gnu-real --PETSC_ARCH=x86_64-linux-gnu-real CFLAGS="-g -O2 -ffile-prefix-map=/build/petsc-pVufYp/petsc-3.14.5+dfsg1=. -flto=auto -ffat-lto-objects -fstack-protector-strong -Wformat -Werror=format-security -fPIC" CXXFLAGS="-g -O2 -ffile-prefix-map=/build/petsc-pVufYp/petsc-3.14.5+dfsg1=. -flto=auto -ffat-lto-objects -fstack-protector-strong -Wformat -Werror=format-security -fPIC" FCFLAGS="-g -O2 -ffile-prefix-map=/build/petsc-pVufYp/petsc-3.14.5+dfsg1=. -flto=auto -ffat-lto-objects -fstack-protector-strong -fPIC -ffree-line-length-0" FFLAGS="-g -O2 -ffile-prefix-map=/build/petsc-pVufYp/petsc-3.14.5+dfsg1=. -flto=auto -ffat-lto-objects -fstack-protector-strong -fPIC -ffree-line-length-0" CPPFLAGS="-Wdate-time -D_FORTIFY_SOURCE=2" LDFLAGS="-Wl,-Bsymbolic-functions -flto=auto -Wl,-z,relro -fPIC" MAKEFLAGS=w
    SLEPc version      : SLEPc Release Version 3.14.2, Feb 01, 2021
    $

Test suite

The test directory contains a set of test cases whose output is known so
that unintended regressions can be detected quickly (see the programming
guide for more information). The test suite ought to be run after each
modification in FeenoX’s source code. It consists of a set of scripts
and input files needed to solve dozens of cases. The output of each
execution is compared to a reference solution. In case the output does
not match the reference, the test suite fails.

After compiling FeenoX as explained in sec. 2.5, the test suite can be
run with make check. Ideally everything should be green meaning the
tests passed:

    $ make check
    Making check in src
    make[1]: Entering directory '/home/gtheler/codigos/feenox/src'
    make[1]: Nothing to be done for 'check'.
    make[1]: Leaving directory '/home/gtheler/codigos/feenox/src'
    make[1]: Entering directory '/home/gtheler/codigos/feenox'
    cp -r src/feenox .
    make  check-TESTS
    make[2]: Entering directory '/home/gtheler/codigos/feenox'
    make[3]: Entering directory '/home/gtheler/codigos/feenox'
    XFAIL: tests/abort.sh
    PASS: tests/algebraic_expr.sh
    PASS: tests/beam-modal.sh
    PASS: tests/beam-ortho.sh
    PASS: tests/builtin.sh
    PASS: tests/cylinder-traction-force.sh
    PASS: tests/default_argument_value.sh
    PASS: tests/expressions_constants.sh
    PASS: tests/expressions_variables.sh
    PASS: tests/expressions_functions.sh
    PASS: tests/exp.sh
    PASS: tests/i-beam-euler-bernoulli.sh
    PASS: tests/iaea-pwr.sh
    PASS: tests/iterative.sh
    PASS: tests/fit.sh
    PASS: tests/function_algebraic.sh
    PASS: tests/function_data.sh
    PASS: tests/function_file.sh
    PASS: tests/function_vectors.sh
    PASS: tests/integral.sh
    PASS: tests/laplace2d.sh
    PASS: tests/materials.sh
    PASS: tests/mesh.sh
    PASS: tests/moment-of-inertia.sh
    PASS: tests/nafems-le1.sh
    PASS: tests/nafems-le10.sh
    PASS: tests/nafems-le11.sh
    PASS: tests/nafems-t1-4.sh
    PASS: tests/nafems-t2-3.sh
    PASS: tests/neutron_diffusion_src.sh
    PASS: tests/neutron_diffusion_keff.sh
    PASS: tests/parallelepiped.sh
    PASS: tests/point-kinetics.sh
    PASS: tests/print.sh
    PASS: tests/thermal-1d.sh
    PASS: tests/thermal-2d.sh
    PASS: tests/trig.sh
    PASS: tests/two-cubes-isotropic.sh
    PASS: tests/two-cubes-orthotropic.sh
    PASS: tests/vector.sh
    XFAIL: tests/xfail-few-properties-ortho-young.sh
    XFAIL: tests/xfail-few-properties-ortho-poisson.sh
    XFAIL: tests/xfail-few-properties-ortho-shear.sh
    ============================================================================
    Testsuite summary for feenox v0.2.6-g3237ce9
    ============================================================================
    # TOTAL: 43
    # PASS:  39
    # SKIP:  0
    # XFAIL: 4
    # FAIL:  0
    # XPASS: 0
    # ERROR: 0
    ============================================================================
    make[3]: Leaving directory '/home/gtheler/codigos/feenox'
    make[2]: Leaving directory '/home/gtheler/codigos/feenox'
    make[1]: Leaving directory '/home/gtheler/codigos/feenox'
    $

The XFAIL result means that those cases are expected to fail (they are
there to test if FeenoX can handle errors). Failure would mean they
passed. In case FeenoX was not compiled with any optional dependency,
the corresponding tests will be skipped. Skipped tests do not mean any
failure, but that the compiled FeenoX executable does not have the full
capabilities. For example, when configuring with
./configure --without-petsc (but with SUNDIALS), the test suite output
should be a mixture of green and blue:

    $ ./configure --without-petsc
    [...]
    configure: creating ./src/version.h
    ## ----------------------- ##
    ## Summary of dependencies ##
    ## ----------------------- ##
      GNU Scientific Library  from system
      SUNDIALS                yes
      PETSc                   no
      SLEPc                   no
      Compiler                gcc
    checking that generated files are newer than configure... done
    configure: creating ./config.status
    config.status: creating Makefile
    config.status: creating src/Makefile
    config.status: creating doc/Makefile
    config.status: executing depfiles commands
    $ make
    [...]
    $ make check
    Making check in src
    make[1]: Entering directory '/home/gtheler/codigos/feenox/src'
    make[1]: Nothing to be done for 'check'.
    make[1]: Leaving directory '/home/gtheler/codigos/feenox/src'
    make[1]: Entering directory '/home/gtheler/codigos/feenox'
    cp -r src/feenox .
    make  check-TESTS
    make[2]: Entering directory '/home/gtheler/codigos/feenox'
    make[3]: Entering directory '/home/gtheler/codigos/feenox'
    XFAIL: tests/abort.sh
    PASS: tests/algebraic_expr.sh
    SKIP: tests/beam-modal.sh
    SKIP: tests/beam-ortho.sh
    PASS: tests/builtin.sh
    SKIP: tests/cylinder-traction-force.sh
    PASS: tests/default_argument_value.sh
    PASS: tests/expressions_constants.sh
    PASS: tests/expressions_variables.sh
    PASS: tests/expressions_functions.sh
    PASS: tests/exp.sh
    SKIP: tests/i-beam-euler-bernoulli.sh
    SKIP: tests/iaea-pwr.sh
    PASS: tests/iterative.sh
    PASS: tests/fit.sh
    PASS: tests/function_algebraic.sh
    PASS: tests/function_data.sh
    PASS: tests/function_file.sh
    PASS: tests/function_vectors.sh
    PASS: tests/integral.sh
    SKIP: tests/laplace2d.sh
    PASS: tests/materials.sh
    PASS: tests/mesh.sh
    PASS: tests/moment-of-inertia.sh
    SKIP: tests/nafems-le1.sh
    SKIP: tests/nafems-le10.sh
    SKIP: tests/nafems-le11.sh
    SKIP: tests/nafems-t1-4.sh
    SKIP: tests/nafems-t2-3.sh
    SKIP: tests/neutron_diffusion_src.sh
    SKIP: tests/neutron_diffusion_keff.sh
    SKIP: tests/parallelepiped.sh
    PASS: tests/point-kinetics.sh
    PASS: tests/print.sh
    SKIP: tests/thermal-1d.sh
    SKIP: tests/thermal-2d.sh
    PASS: tests/trig.sh
    SKIP: tests/two-cubes-isotropic.sh
    SKIP: tests/two-cubes-orthotropic.sh
    PASS: tests/vector.sh
    SKIP: tests/xfail-few-properties-ortho-young.sh
    SKIP: tests/xfail-few-properties-ortho-poisson.sh
    SKIP: tests/xfail-few-properties-ortho-shear.sh
    ============================================================================
    Testsuite summary for feenox v0.2.6-g3237ce9
    ============================================================================
    # TOTAL: 43
    # PASS:  21
    # SKIP:  21
    # XFAIL: 1
    # FAIL:  0
    # XPASS: 0
    # ERROR: 0
    ============================================================================
    make[3]: Leaving directory '/home/gtheler/codigos/feenox'
    make[2]: Leaving directory '/home/gtheler/codigos/feenox'
    make[1]: Leaving directory '/home/gtheler/codigos/feenox'
    $

To illustrate how regressions can be detected, let us add a bug
deliberately and re-run the test suite.

Edit the source file that contains the shape functions of the
second-order tetrahedra src/mesh/tet10.c, find the function
feenox_mesh_tet10_h() and randomly change a sign, i.e. replace

          return t*(2*t-1);

with

          return t*(2*t+1);

Save, recompile, and re-run the test suite to obtain some red:

    $ git diff src/mesh/
    diff --git a/src/mesh/tet10.c b/src/mesh/tet10.c
    index 72bc838..293c290 100644
    --- a/src/mesh/tet10.c
    +++ b/src/mesh/tet10.c
    @@ -227,7 +227,7 @@ double feenox_mesh_tet10_h(int j, double *vec_r) {
           return s*(2*s-1);
           break;
         case 3:
    -      return t*(2*t-1);
    +      return t*(2*t+1);
           break;
           
         case 4:
    $ make
    [...]
    $ make check
    Making check in src
    make[1]: Entering directory '/home/gtheler/codigos/feenox/src'
    make[1]: Nothing to be done for 'check'.
    make[1]: Leaving directory '/home/gtheler/codigos/feenox/src'
    make[1]: Entering directory '/home/gtheler/codigos/feenox'
    cp -r src/feenox .
    make  check-TESTS
    make[2]: Entering directory '/home/gtheler/codigos/feenox'
    make[3]: Entering directory '/home/gtheler/codigos/feenox'
    XFAIL: tests/abort.sh
    PASS: tests/algebraic_expr.sh
    FAIL: tests/beam-modal.sh
    PASS: tests/beam-ortho.sh
    PASS: tests/builtin.sh
    PASS: tests/cylinder-traction-force.sh
    PASS: tests/default_argument_value.sh
    PASS: tests/expressions_constants.sh
    PASS: tests/expressions_variables.sh
    PASS: tests/expressions_functions.sh
    PASS: tests/exp.sh
    PASS: tests/i-beam-euler-bernoulli.sh
    PASS: tests/iaea-pwr.sh
    PASS: tests/iterative.sh
    PASS: tests/fit.sh
    PASS: tests/function_algebraic.sh
    PASS: tests/function_data.sh
    PASS: tests/function_file.sh
    PASS: tests/function_vectors.sh
    PASS: tests/integral.sh
    PASS: tests/laplace2d.sh
    PASS: tests/materials.sh
    PASS: tests/mesh.sh
    PASS: tests/moment-of-inertia.sh
    PASS: tests/nafems-le1.sh
    FAIL: tests/nafems-le10.sh
    FAIL: tests/nafems-le11.sh
    PASS: tests/nafems-t1-4.sh
    PASS: tests/nafems-t2-3.sh
    PASS: tests/neutron_diffusion_src.sh
    PASS: tests/neutron_diffusion_keff.sh
    FAIL: tests/parallelepiped.sh
    PASS: tests/point-kinetics.sh
    PASS: tests/print.sh
    PASS: tests/thermal-1d.sh
    PASS: tests/thermal-2d.sh
    PASS: tests/trig.sh
    PASS: tests/two-cubes-isotropic.sh
    PASS: tests/two-cubes-orthotropic.sh
    PASS: tests/vector.sh
    XFAIL: tests/xfail-few-properties-ortho-young.sh
    XFAIL: tests/xfail-few-properties-ortho-poisson.sh
    XFAIL: tests/xfail-few-properties-ortho-shear.sh
    ============================================================================
    Testsuite summary for feenox v0.2.6-g3237ce9
    ============================================================================
    # TOTAL: 43
    # PASS:  35
    # SKIP:  0
    # XFAIL: 4
    # FAIL:  4
    # XPASS: 0
    # ERROR: 0
    ============================================================================
    See ./test-suite.log
    Please report to jeremy@seamplex.com
    ============================================================================
    make[3]: *** [Makefile:1152: test-suite.log] Error 1
    make[3]: Leaving directory '/home/gtheler/codigos/feenox'
    make[2]: *** [Makefile:1260: check-TESTS] Error 2
    make[2]: Leaving directory '/home/gtheler/codigos/feenox'
    make[1]: *** [Makefile:1791: check-am] Error 2
    make[1]: Leaving directory '/home/gtheler/codigos/feenox'
    make: *** [Makefile:1037: check-recursive] Error 1
    $

  [test]: https://github.com/seamplex/feenox/tree/main/tests
  [programming guide]: programming.md

Installation

To be able to execute FeenoX from any directory, the binary has to be
copied to a directory available in the PATH environment variable. If you
have root access, the easiest and cleanest way of doing this is by
calling make install with sudo or su:

    $ sudo make install
    Making install in src
    make[1]: Entering directory '/home/gtheler/codigos/feenox/src'
    gmake[2]: Entering directory '/home/gtheler/codigos/feenox/src'
     /usr/bin/mkdir -p '/usr/local/bin'
      /usr/bin/install -c feenox '/usr/local/bin'
    gmake[2]: Nothing to be done for 'install-data-am'.
    gmake[2]: Leaving directory '/home/gtheler/codigos/feenox/src'
    make[1]: Leaving directory '/home/gtheler/codigos/feenox/src'
    make[1]: Entering directory '/home/gtheler/codigos/feenox'
    cp -r src/feenox .
    make[2]: Entering directory '/home/gtheler/codigos/feenox'
    make[2]: Nothing to be done for 'install-exec-am'.
    make[2]: Nothing to be done for 'install-data-am'.
    make[2]: Leaving directory '/home/gtheler/codigos/feenox'
    make[1]: Leaving directory '/home/gtheler/codigos/feenox'
    $

If you do not have root access or do not want to populate
/usr/local/bin, you can either

- Configure with a different prefix (not covered here), or

- Copy (or symlink) the feenox executable to $HOME/bin:

      mkdir -p ${HOME}/bin
      cp feenox ${HOME}/bin

  If you plan to regularly update FeenoX (which you should), you might
  want to symlink instead of copy so you do not need to update the
  binary in $HOME/bin each time you recompile:

      mkdir -p ${HOME}/bin
      ln -sf feenox ${HOME}/bin

Check that FeenoX is now available from any directory (note the command
is feenox and not ./feenox):

    $ cd
    $ feenox -v
    FeenoX v0.2.14-gbbf48c9
    a free no-fee no-X uniX-like finite-element(ish) computational engineering tool

    Copyright © 2009--2022 https://seamplex.com/feenox
    GNU General Public License v3+, https://www.gnu.org/licenses/gpl.html. 
    FeenoX is free software: you are free to change and redistribute it.
    There is NO WARRANTY, to the extent permitted by law.
    $

If it is not and you went through the $HOME/bin path, make sure it is in
the PATH (pun). Add

    export PATH=${PATH}:${HOME}/bin

to your .bashrc in your home directory and re-login.

Advanced settings

Compiling with debug symbols

By default the C flags are -O3, without debugging. To add the -g flag,
just use CFLAGS when configuring:

    ./configure CFLAGS="-g -O0"

Using a different compiler

FeenoX uses the CC environment variable to set the compiler. So
configure like

    export CC=clang; ./configure

Note that the CC variable has to be exported and not passed to
configure. That is to say, don’t configure like

    ./configure CC=clang

Mind also the following environment variables when using MPI-enabled
PETSc:

- MPICH_CC
- OMPI_CC
- I_MPI_CC

Depending on how your system is configured, this last command might show
clang but not actually use it. The FeenoX executable will show the
configured compiler and flags when invoked with the --versions option:

    $ feenox --versions
    FeenoX v0.2.14-gbbf48c9
    a free no-fee no-X uniX-like finite-element(ish) computational engineering tool

    Last commit date   : Sat Feb 12 15:35:05 2022 -0300
    Build date         : Sat Feb 12 15:35:44 2022 -0300
    Build architecture : linux-gnu x86_64
    Compiler version   : gcc (Debian 10.2.1-6) 10.2.1 20210110
    Compiler expansion : gcc -Wl,-z,relro -I/usr/include/x86_64-linux-gnu/mpich -L/usr/lib/x86_64-linux-gnu -lmpich
    Compiler flags     : -O3
    Builder            : gtheler@tom
    GSL version        : 2.6
    SUNDIALS version   : 5.7.0
    PETSc version      : Petsc Release Version 3.16.3, Jan 05, 2022 
    PETSc arch         : arch-linux-c-debug
    PETSc options      : --download-eigen --download-hdf5 --download-hypre --download-metis --download-mumps --download-parmetis --download-pragmatic --download-scalapack
    SLEPc version      : SLEPc Release Version 3.16.1, Nov 17, 2021
    $

You can check which compiler was actually used by analyzing the feenox
binary as

    $ objdump -s --section .comment ./feenox 

    ./feenox:     file format elf64-x86-64

    Contents of section .comment:
     0000 4743433a 20284465 6269616e 2031322e  GCC: (Debian 12.
     0010 322e302d 31342920 31322e32 2e300044  2.0-14) 12.2.0.D
     0020 65626961 6e20636c 616e6720 76657273  ebian clang vers
     0030 696f6e20 31342e30 2e3600             ion 14.0.6.     
    $ 

It should be noted that the MPI implementation used to compile FeenoX
has to match the one used to compile PETSc. Therefore, if you compiled
PETSc on your own, it is up to you to ensure MPI compatibility. If you
are using PETSc as provided by your distribution’s repositories, you
will have to find out which one was used (it is usually OpenMPI) and use
the same one when compiling FeenoX. FeenoX has been tested using PETSc
compiled with

- MPICH
- OpenMPI
- Intel MPI

Compiling PETSc

Particular explanation for FeenoX is to be done. For now, follow the
general explanation from PETSc’s website.

    export PETSC_DIR=$PWD
    export PETSC_ARCH=arch-linux-c-opt
    ./configure --with-debugging=0 --download-mumps --download-scalapack --with-cxx=0 --COPTFLAGS=-O3 --FOPTFLAGS=-O3 

    export PETSC_DIR=$PWD
    ./configure --with-debugging=0 --with-openmp=0 --with-x=0 --with-cxx=0 --COPTFLAGS=-O3 --FOPTFLAGS=-O3 
    make PETSC_DIR=/home/ubuntu/reflex-deps/petsc-3.17.2 PETSC_ARCH=arch-linux-c-opt all

  [general explanation from PETSc’s website]: https://petsc.org/release/install/
