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TiledCollapser.h
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//# TiledCollapser.h: Abstract base class to collapse chunks for LatticeApply
//# Copyright (C) 1996,1997,1998
//# 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 LATTICES_TILEDCOLLAPSER_H
#define LATTICES_TILEDCOLLAPSER_H
//# Includes
#include <casacore/casa/aips.h>
#include <casacore/casa/Arrays/ArrayFwd.h>
#include <casacore/scimath/Mathematics/NumericTraits.h>
namespace casacore { //# NAMESPACE CASACORE - BEGIN
//# Forward Declarations
class IPosition;
// <summary>
// Abstract base class to collapse chunks for LatticeApply
// </summary>
// <use visibility=export>
// <reviewed reviewer="" date="yyyy/mm/dd" tests="" demos="">
// </reviewed>
// <prerequisite>
// <li> <linkto class=LatticeApply>LatticeApply</linkto>
// </prerequisite>
// <etymology>
// </etymology>
// <synopsis>
// This is an abstract base class for the collapsing of chunks to
// be used in function <src>tiledApply</src>
// in class <linkto class=LatticeApply>LatticeApply</linkto>.
// It is meant for cases where an entire line or plane is not needed
// (e.g. calculation of maximum). If that is needed (e.g. to calculate moment),
// it is better to use function <src>LatticeApply::lineApply</src>
// with class <linkto class=LineCollapser>LineCollapser</linkto>.
// <p>
// The user has to derive a concrete class from this base class
// and implement the (pure) virtual functions.
// <br> The main function is <src>process</src>, which needs to do the
// calculation.
// <br> Other functions make it possible to perform an initial check.
// <p>
// The class is Doubly templated. Ths first template type
// is for the data type you are processing. The second type is
// for what type you want the results of the processing assigned to.
// For example, if you are computing sums of squares for statistical
// purposes, you might use higher precision (FLoat->Double) for this.
// No check is made that the template types are self-consistent.
// </synopsis>
// <example>
// <srcblock>
// </srcblock>
// </example>
// <motivation>
// </motivation>
// <todo asof="1997/08/01">
// <li>
// </todo>
template <class T, class U=T> class TiledCollapser
{
public:
// Destructor
virtual ~TiledCollapser();
// The init function for a derived class.
// It can be used to check if <src>nOutPixelsPerCollapse</src>
// corresponds with the number of pixels produced per collapsed chunk.
// <br><src>processAxis</src> is the axis of the line being passed
// to the <src>process</src> function.
virtual void init (uInt nOutPixelsPerCollapse) = 0;
// Can the process function in the derived class handle a null mask pointer?
// If not, LatticeApply ensures that it'll always pass a mask block,
// even if the lattice does not have a mask (in that case that mask block
// contains all True values).
// <br>The default implementation returns False.
// <br>The function is there to make optimization possible when no masks
// are involved. On the other side, it allows the casual user to ignore
// optimization.
virtual Bool canHandleNullMask() const;
// Create and initialize the accumulator.
// The accumulator can be a cube with shape [n1,n2,n3],
// where <src>n2</src> is equal to <src>nOutPixelsPerCollapse</src>.
// However, one can also use several matrices as accumulator.
// <br> The data type of the accumulator can be any. E.g. when
// accumulating Float lattices, the accumulator could be of
// type Double to have enough precision.
// <br>In the <src>endAccumulator</src> function the accumulator
// data has to be copied into an Array object with the correct
// shape and data type.
virtual void initAccumulator (uInt64 n1, uInt64 n3) = 0;
// Collapse the given input data containing (<src>nrval</src> values
// with an increment of <src>inDataIncr</src> elements).
// <src>inMask</src> is a Bool block representing a mask with the
// same nr of values and increment as the input data. If a mask
// value is False, the corresponding input value is masked off.
// <br>When function <src>canHandleNullMask</src> returned True,
// it is possible that <src>inMask</src> is a null pointer indicating
// that the input has no mask, thus all values are valid.
// <br>
// The result(s) have to be stored in the accumulator at the given indices.
// <br><src>startPos</src> gives the lattice position of the first value.
// The position of other values can be calculated from index and shape
// using function <src>toPositionInArray</src> in class
// <linkto class=IPosition>IPosition</linkto>.
virtual void process (uInt accumIndex1, uInt accumIndex3,
const T* inData, const Bool* inMask,
uInt inDataIncr, uInt inMaskIncr,
uInt nrval,
const IPosition& startPos,
const IPosition& shape) = 0;
// End the accumulator. It should return the accumulator as an
// Array of datatype U (e.g. double the precision of type T)
// with the given shape. The accumulator should thereafter be deleted when needed.
virtual void endAccumulator (Array<U>& result,
Array<Bool>& resultMask,
const IPosition& shape) = 0;
};
} //# NAMESPACE CASACORE - END
#ifndef CASACORE_NO_AUTO_TEMPLATES
#include <casacore/lattices/LatticeMath/TiledCollapser.tcc>
#endif //# CASACORE_NO_AUTO_TEMPLATES
#endif
casacore::Array
Definition Array.h:155
casacore::IPosition
Definition IPosition.h:117
casacore::TiledCollapser
Definition TiledCollapser.h:93
casacore::TiledCollapser::initAccumulator
virtual void initAccumulator(uInt64 n1, uInt64 n3)=0
Create and initialize the accumulator.
casacore::TiledCollapser::endAccumulator
virtual void endAccumulator(Array< U > &result, Array< Bool > &resultMask, const IPosition &shape)=0
End the accumulator.
casacore::TiledCollapser::~TiledCollapser
virtual ~TiledCollapser()
Destructor.
casacore::TiledCollapser::canHandleNullMask
virtual Bool canHandleNullMask() const
Can the process function in the derived class handle a null mask pointer?
casacore::TiledCollapser::init
virtual void init(uInt nOutPixelsPerCollapse)=0
The init function for a derived class.
casacore::TiledCollapser::process
virtual void process(uInt accumIndex1, uInt accumIndex3, const T *inData, const Bool *inMask, uInt inDataIncr, uInt inMaskIncr, uInt nrval, const IPosition &startPos, const IPosition &shape)=0
Collapse the given input data containing (nrval values with an increment of inDataIncr elements).
casacore
this file contains all the compiler specific defines
Definition mainpage.dox:28
casacore::uInt
unsigned int uInt
Definition aipstype.h:49
casacore::shape
IPosition shape(const RecordFieldId &) const
Get the actual shape of this field.
casacore::Bool
bool Bool
Define the standard types used by Casacore.
Definition aipstype.h:40
casacore::uInt64
unsigned long long uInt64
Definition aipsxtype.h:37