Generate histograms, tile by tile, from a masked lattice. More...

#include <LatticeHistograms.h>

Inheritance diagram for casa::HistTiledCollapser< T >:

Public Member Functions
	HistTiledCollapser (LatticeStatistics< T > *pStats, uInt nBins)
	Constructor.
virtual void	init (uInt nOutPixelsPerCollapse)
	Initialize process, making some checks.
virtual void	initAccumulator (uInt n1, uInt n3)
	Initialize the accumulator.
virtual void	process (uInt accumIndex1, uInt accumIndex3, const T inData, const Bool inMask, uInt inIncr, uInt nrval, const IPosition &startPos, const IPosition &shape)
	Process the data in the current chunk.
virtual void	endAccumulator (Array< T > &result, Array< Bool > &resultMask, const IPosition &shape)
	End the accumulation process and return the result arrays.
virtual Bool	canHandleNullMask () const
	Can handle null mask.
Private Attributes
LatticeStatistics< T > *	pStats_p
Block< T > *	pHist_p
uInt	nBins_p
uInt	n1_p
uInt	n3_p

Detailed Description

template<class T>
class casa::HistTiledCollapser< T >

Generate histograms, tile by tile, from a masked lattice.

Intended use:

Public interface

Review Status

Date Reviewed:: yyyy/mm/dd

Prerequisite

Etymology

This class is used by LatticeHistograms to generate histograms from an input MaskedLattice. The input lattice is iterated through in tile-sized chunks and fed to an object of this class.

Synopsis

HistTiledCollapser is derived from TiledCollapser which is a base class used to define methods. Objects of this base class are used by LatticeApply functions. In this particular case, we are interested in LatticeApply::tiledApply. This function iterates through a MaskedLattice and allows you to collapse one or more axes, computing some values from it, and placing those values into an output MaskedLattice. It iterates through the input lattice in optimal tile-sized chunks. LatticeHistograms uses a HistTiledCollapser object which it gives to LatticeApply::tiledApply for digestion. After it has done its work, LatticeHistograms then accesses the output Lattice that it made.

Example

   // Created collapser. Control information is passed in via the constructor.
   
      HistTiledCollapser<T> collapser(pStats, nBins_p);
    
   // This is the first output axis getting  collapsed values. In LatticeHistograms
   // this is the first axis of the output lattice
    
      Int newOutAxis = 0;
   
   // tiledApply does the work by passing the collapser data in chunks
   // and by writing the results into the output lattice 
   
      LatticeApply<T>::tiledApply(outLattice, inLattice,
                                  collapser, collapseAxes,
                                  newOutAxis);

In this example, a collapser is made and passed to LatticeApply. Afterwards, the output Lattice is available for use. The Lattices must all be the correct shapes on input to tiledApply

Motivation

The LatticeApply classes enable the ugly details of optimal Lattice iteration to be hidden from the user.

To Do

Definition at line 455 of file LatticeHistograms.h.

Constructor & Destructor Documentation

template<class T >

casa::HistTiledCollapser< T >::HistTiledCollapser	(	LatticeStatistics< T > *	pStats,
		uInt	nBins
	)

Constructor.

Member Function Documentation

template<class T >

virtual Bool casa::HistTiledCollapser< T >::canHandleNullMask ( ) const [inline, virtual]

Can handle null mask.

Reimplemented from casa::TiledCollapser< T, T >.

Definition at line 484 of file LatticeHistograms.h.

template<class T >

virtual void casa::HistTiledCollapser< T >::endAccumulator	(	Array< T > &	result,
		Array< Bool > &	resultMask,
		const IPosition &	shape
	)			`[virtual]`

End the accumulation process and return the result arrays.

Implements casa::TiledCollapser< T, T >.

template<class T >

virtual void casa::HistTiledCollapser< T >::init ( uInt nOutPixelsPerCollapse ) [virtual]

Initialize process, making some checks.

Implements casa::TiledCollapser< T, T >.

template<class T >

virtual void casa::HistTiledCollapser< T >::initAccumulator	(	uInt	n1,
		uInt	n3
	)			`[virtual]`

Initialize the accumulator.

Implements casa::TiledCollapser< T, T >.

template<class T >

virtual void casa::HistTiledCollapser< T >::process	(	uInt	accumIndex1,
		uInt	accumIndex3,
		const T *	inData,
		const Bool *	inMask,
		uInt	inIncr,
		uInt	nrval,
		const IPosition &	startPos,
		const IPosition &	shape
	)			`[virtual]`