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PositionEngine.h
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//# PositionEngine.h: Engine for TaQL UDF Position conversions
//# Copyright (C) 2011
//# Associated Universities, Inc. Washington DC, USA.
//#
//# This library is free software; you can redistribute it and/or modify it
//# under the terms of the GNU Library General Public License as published by
//# the Free Software Foundation; either version 2 of the License, or (at your
//# option) any later version.
//#
//# This library is distributed in the hope that it will be useful, but WITHOUT
//# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
//# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
//# License for more details.
//#
//# You should have received a copy of the GNU Library General Public License
//# along with this library; if not, write to the Free Software Foundation,
//# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
//#
//# Correspondence concerning AIPS++ should be addressed as follows:
//# Internet email: casa-feedback@nrao.edu.
//# Postal address: AIPS++ Project Office
//# National Radio Astronomy Observatory
//# 520 Edgemont Road
//# Charlottesville, VA 22903-2475 USA
#ifndef MEAS_POSITIONENGINE_H
#define MEAS_POSITIONENGINE_H
//# Includes
#include <casacore/casa/aips.h>
#include<casacore/meas/MeasUDF/MeasEngine.h>
#include <casacore/measures/Measures/MPosition.h>
#include <casacore/measures/Measures/MCPosition.h>
#include <casacore/measures/Measures/MeasConvert.h>
namespace casacore {
// <summary>
// Engine for TaQL UDF Position conversions
// </summary>
// <use visibility=export>
// <reviewed reviewer="" date="" tests="tMeas.cc">
// </reviewed>
// <prerequisite>
//# Classes you should understand before using this one.
// <li> EngineBase
// </prerequisite>
// <synopsis>
// PositionEngine defines Engines (user defined functions) that can be used
// in TaQL to convert Measures for positions.
// In this way such derived values appear to be ordinary TaQL functions.
//
// In TaQL these functions can be called like:
// <srcblock>
// meas.pos (toref, pos)
// meas.wgs (pos)
// meas.itrfxyz (pos)
// For example,
// meas.pos ('ITRF', [1e6m,1e6m,1e6m], 'WGS84')
// </srcblock>
// <ul>
// <li> <src>toref</src> is a single constant string defining the
// reference frame to convert to. Note it should be omitted for
// the functions (e.g., meas.wgs) with an implicit destination
// reference frame.
// The reference type WGS84 or ITRF can optionally have the suffix
// XYZ, LLH, LL (or LONLAT) and H (or HEIGHT) telling how the result
// should be returned.
// <li> <src>pos</src> specifies the position(s) which can be done in
// various ways.
// <ul>
// <li> An array of positions given as xyz, as lonlat, as lon-lat-height
// or as height. The latter is taken towards the pole.
// Note that specifying as lon-lat-height precludes use of units
// (angle and length units cannot be mixed in a TaQL value).
// It can be given as a single list or a multi-dim array.
// If given as lonlat it can be followed by an array defining
// the height for each lon,lat pair (their sizes should match).
// Finally it can be followed by a string defining the source
// reference type, which defaults to ITRF for x,y,z and WGS84
// for lon,lat.
// The source reference type can contain the suffix XYZ, LLH, LL
// or H to tell how the values are specified. If no suffix is given,
// it is derived from the unit of the first value (angle means LL,
// length means XYZ).
// <li> If a single constant position is used, it can be given as
// 1, 2 or 3 scalar values, optionally followed by the source
// reference type. If x,y,z or lon,lat or lon,lat,h or h is given
// is derived in the same way as above.
// <li> The name of a column in a table or a subset of it such as
// <src>POSITION[0,]</src>. Often this is a TableMeasures column
// which is recognized as such, also its source reference frame.
// If such a column is used in a expression, it will not be
// recognized as a TableMeasures column and its reference frame
// should be given.
// <li> As a list containing (case-insensitive) names of known
// observatories such as 'WSRT' or 'VLA'.
// </ul>
// </ul>
//
// The result of the function is an array with shape [2|3,pos] if
// lon,lat(,h) or x,y,z is returned and shape [pos] if height is returned.
// The last element is the shape of the position argument. It is omitted if
// it has length 1. In such a case getting the height results in a scalar.
// </synopsis>
// <example>
// <srcblock>
// // Get the WGS84 lon,lat of WSRT (in degrees).
// meas.wgsll ('WSRT') deg
// // Get the ITRF x,y,z of WSRT and VLA.
// meas.itrfxyz (['WSRT', 'VLA'])
// </srcblock>
// </example>
// <motivation>
// It makes it possible to handle measures in TaQL.
// </motivation>
class PositionEngine: public MeasEngine<MPosition>
{
public:
PositionEngine();
virtual ~PositionEngine();
// Get the value type. It also gives the nr of output values per position.
// 0=default, 1=height, 2=angles, 3=xyz
Int valueType() const
{ return itsValueType; }
// Get the values.
Array<Double> getArrayDouble (const TableExprId& id,
MPosition::Types toRefType,
Int toValueType);
// Get the positions.
Array<MPosition> getPositions (const TableExprId& id);
// Handle the argument(s) giving the input positions and reference type.
// The position can be a column in a table.
void handlePosition (Int toValueType,
const std::vector<TENShPtr>& args,
uInt& argnr);
private:
virtual String stripMeasType (const String& type);
virtual void deriveAttr (const Unit& unit, Int nval);
// Let a derived class set its value type.
// By default is does nothing.
virtual void setValueType (Int valueType);
// Make an MPosition from xyz or height,angles.
MPosition makePosition (const Quantity& qh,
const Quantity& q1,
const Quantity& q2) const;
void handleScalars (const TENShPtr& e1, const TENShPtr& e2,
const TENShPtr& e3, Int nval);
void handleObservatory (const TENShPtr& operand);
void handlePosArray (const TENShPtr& angles, const TENShPtr& height);
virtual void handleValues (TableExprNode& operand,
const TableExprId& id,
Array<MPosition>& positions);
//# Data members.
//# 0=unknown, 1=height, 2=angles, 3=xyz, -3=angles,height
Int itsValueType;
};
} //end namespace
#endif
casacore::type
casacore::Array
Definition Array.h:155
casacore::BaseEngine::unit
const Unit & unit() const
Get the unit of the function's result.
Definition BaseEngine.h:121
casacore::MPosition
Definition MPosition.h:76
casacore::MPosition::Types
Types
Types of known MPositions Warning: The order defines the order in the translation matrix FromTo in t...
Definition MPosition.h:91
casacore::MeasEngine< MPosition >::MeasEngine
MeasEngine()
Definition MeasEngine.h:93
casacore::PositionEngine::valueType
Int valueType() const
Get the value type.
Definition PositionEngine.h:133
casacore::PositionEngine::makePosition
MPosition makePosition(const Quantity &qh, const Quantity &q1, const Quantity &q2) const
Make an MPosition from xyz or height,angles.
casacore::PositionEngine::setValueType
virtual void setValueType(Int valueType)
Let a derived class set its value type.
casacore::PositionEngine::stripMeasType
virtual String stripMeasType(const String &type)
Let a derived class strip part of the reference type.
casacore::PositionEngine::getArrayDouble
Array< Double > getArrayDouble(const TableExprId &id, MPosition::Types toRefType, Int toValueType)
Get the values.
casacore::PositionEngine::handleScalars
void handleScalars(const TENShPtr &e1, const TENShPtr &e2, const TENShPtr &e3, Int nval)
casacore::PositionEngine::handleObservatory
void handleObservatory(const TENShPtr &operand)
casacore::PositionEngine::deriveAttr
virtual void deriveAttr(const Unit &unit, Int nval)
Let a derived class derive its attributes.
casacore::PositionEngine::handleValues
virtual void handleValues(TableExprNode &operand, const TableExprId &id, Array< MPosition > &positions)
Let a derive class handle the values.
casacore::PositionEngine::itsValueType
Int itsValueType
Definition PositionEngine.h:171
casacore::PositionEngine::~PositionEngine
virtual ~PositionEngine()
casacore::PositionEngine::handlePosArray
void handlePosArray(const TENShPtr &angles, const TENShPtr &height)
casacore::PositionEngine::handlePosition
void handlePosition(Int toValueType, const std::vector< TENShPtr > &args, uInt &argnr)
Handle the argument(s) giving the input positions and reference type.
casacore::PositionEngine::getPositions
Array< MPosition > getPositions(const TableExprId &id)
Get the positions.
casacore::PositionEngine::PositionEngine
PositionEngine()
casacore::String
String: the storage and methods of handling collections of characters.
Definition String.h:223
casacore::TableExprId
Definition TableExprId.h:95
casacore::TableExprNode
Definition ExprNode.h:154
casacore::Unit
Definition Unit.h:187
casacore
this file contains all the compiler specific defines
Definition mainpage.dox:28
casacore::uInt
unsigned int uInt
Definition aipstype.h:49
casacore::TENShPtr
std::shared_ptr< TableExprNodeRep > TENShPtr
Definition ExprNodeRep.h:55
casacore::Int
int Int
Definition aipstype.h:48
casacore::Quantity
Quantum< Double > Quantity
Definition Quantum.h:39