MSSelector specifies selections on a MeasurementSet. More...

#include <MSSelector.h>

Public Member Functions
	MSSelector ()
	MSSelector (MeasurementSet &ms)
	construct from an MS, the MS will supply the range of the various parameters that can be selected on.
	MSSelector (const MSSelector &other)
	Copy constructor, this will initialize the MS with other's MS.
MSSelector &	operator= (const MSSelector &other)
	Assignment, this will initialize the MS with other's MS.
	~MSSelector ()
void	setMS (MeasurementSet &ms)
	Change or Set the MS this MSSelector refers to.
Bool	initSelection (const Vector< Int > &dataDescIds, Bool reset=False)
	initialize the selection by specifying, optionally, the DATA_DESC_IDs.
Bool	initSelection (Bool reset=False)
	As above without the data desc id argument.
Vector< Int >	dataDescId () const
	Return the data desc IDs selected.
Bool	selectChannel (Int nChan, Int start, Int width, Int incr)
	Set the mapping from input channels in the DATA column to output channels.
Bool	selectPolarization (const Vector< String > &wantedPol)
	Specify the output polarization.
Bool	select (const Record &items, Bool oneBased=False)
	Select the MS based on the selections present in the input record.
Bool	select (const String &msSelect)
	Select the MS based on the TaQL selection string.
Record	getData (const Vector< String > &items, Bool ifrAxis, Int ifrAxisGap=0, Int inc=1, Bool average=False, Bool oneBased=False)
	Return the data for the items requested, all returned values will be arrays, the last dimension of these is the table row number.
Bool	putData (const Record &items)
	Put the data for the items provided.
Bool	iterInit (const Vector< String > &columns, Double interval, Int maxRows=0, Bool addDefaultSortColumns=True)
	Set up an iterator, iterating over the specified columns, with optional time interval and maximum number of rows to return at once (the default of zero returns all rows).
Bool	iterNext ()
	Step the iterator, sets the selection to the current table iteration.
Bool	iterOrigin ()
	(Re)Set the iterator to the first iteration, call this after iterInit.
Bool	iterEnd ()
	End the iteration (before reaching the last iteration)
Int	nrow () const
	Number of rows in selected table.
Table	selectedTable () const
	Return the selected table.
Bool	selected () const
	Return the selection status of the table.
Protected Member Functions
void	getAveragedData (Array< Complex > &avData, const Array< Bool > &flag, const ArrayColumn< Complex > &col) const
	average and convert data
void	getAveragedData (Array< Float > &avData, const Array< Bool > &flag, const ArrayColumn< Float > &col) const
	average and convert float data
void	getAveragedData (Array< Complex > &avData, const Array< Bool > &flag, const ArrayColumn< Complex > &col, const Slicer &rowSlicer) const
	average and convert data, with row Slicer
void	getAveragedData (Array< Float > &avData, const Array< Bool > &flag, const ArrayColumn< Float > &col, const Slicer &rowSlicer) const
	average and convert float data, with row Slicer
Array< Bool >	getAveragedFlag (Array< Bool > &avFlag, const ArrayColumn< Bool > &col) const
	"average" flag, at present all output which has a flagged input is flagged
Array< Bool >	getAveragedFlag (Array< Bool > &avFlag, const ArrayColumn< Bool > &col, const Slicer &rowSlicer) const
	"average" flag, at present all output which has a flagged input is flagged, with row Slicer
void	putAveragedFlag (const Array< Bool > &avFlag, ArrayColumn< Bool > &col)
	"unaverage" flag, distribute the flags back to the channels that went into the average
Array< Float >	getWeight (const ArrayColumn< Float > &wtCol, Bool sigma=False) const
	get the weight, set sigma=True when retrieving sigma's
void	makeSlicer (Int start, Int nCorr) const
	make the data slicer, pass in the first and the number of correlations to select
void	reorderFlagRow (Array< Bool > &flagRow)
	reorder from 2d to 1d (removing ifr axis)
void	reorderWeight (Array< Float > &weight)
	reorder from 2d to 1d (removing ifr axis)
void	timeAverage (Array< Bool > &dataFlags, Array< Complex > &data, const Array< Bool > &flags, const Array< Float > &weights)
	time average the input data, return new flags
Bool	checkSelection ()
	check if the data description selection has been done & do default selection if not.
Private Types
enum	{ Amp, Phase, Real, Imag, Data, nFuncType }
	The function types. More...
enum	{ Observed, Corrected, Model, Ratio, Residual, ObsResidual, ObsFloat, nDataType }
	The data types. More...
Private Attributes
MeasurementSet	ms_p
MeasurementSet	selms_p
MeasurementSet	savems_p
MSIter *	msIter_p
Bool	initSel_p
Vector< Int >	dataDescId_p
Vector< Int >	lastDataDescId_p
Vector< uInt >	spwId_p
Vector< uInt >	polId_p
Vector< Int >	chanSel_p
Bool	useSlicer_p
Bool	haveSlicer_p
Slicer	slicer_p
Slice	chanSlice_p
Slice	polSlice_p
Vector< Int >	polIndex_p
Int	wantedOne_p
Bool	convert_p
Bool	subSet_p
StokesConverter	stokesConverter_p
Vector< String >	polSelection_p
Vector< Int >	ifrSelection_p
Vector< Int >	ifrAxis_p
Matrix< Double >	chanFreq_p
Matrix< Double >	bandwidth_p
MSDerivedValues	msd_p
Matrix< Int >	rowIndex_p
Vector< uInt >	selRows_p
Int	startRow_p
Int	maxRow_p
Bool	useIfrDefault_p
Friends
class	MSRange

Detailed Description

MSSelector specifies selections on a MeasurementSet.

Intended use:

Public interface

Review Status

Date Reviewed:: yyyy/mm/dd

Prerequisite

Etymology

MSSelector's main function is selection of data from a MeasurementSet

Synopsis

This class is used to select and retrieve data from a MeasurementSet. It allows selections on e.g., time, field, spectral window (all row based), but also on channel and polarization (within a row). It can optionally do polarization conversion, spectral averaging and time averaging on the data retrieved and allows modified data to be written back to the Table. This class also provides the DO interface to the MS Iterator. The ms DO uses this class to allow these operations to be done from glish.

Example

    MSSelector msSelector(myMS);
    // select data desc Id 1
    msSelector.initSelection(1);
    Vector<String> items(3); 
    // fill in some fields
    items(0)="field_id";
    items(1)="time";
    items(2)="num_chan";
    // get the range of values for the items specified
    MSRange msRange(msSelector.selectedTable(),msSelector.spectralWindow());
    Record range=msRange.range(items);
    //.. change the ranges as needed
    // now select with the new range
    msSelector.select(range);
    Int nchan=10, start=3, width=1, incr=2;
    msSelector.selectChannel(nchan,start,width,incr)
    // get out some data
    Vector<String> dataItems(3);
    dataItems(0)="data";
    dataItems(1)="antenna1";
    dataItems(2)="antenna2";
    Record dataRec=msSelector.getData(items);

Motivation

Selection from an MS is needed in various places. It makes sense to provide a uniform interface for MS selection.

Thrown Exceptions

To Do

provide access to all other columns in the MS?

Definition at line 113 of file MSSelector.h.

Member Enumeration Documentation

anonymous enum [private]

The function types.

Enumerator:

Amp
Phase
Real
Imag
Data
nFuncType

Definition at line 292 of file MSSelector.h.

anonymous enum [private]

The data types.

Enumerator:

Observed
Corrected
Model
Ratio
Residual
ObsResidual
ObsFloat
nDataType

Definition at line 295 of file MSSelector.h.

Constructor & Destructor Documentation

casa::MSSelector::MSSelector ( )

casa::MSSelector::MSSelector ( MeasurementSet & ms ) [explicit]

construct from an MS, the MS will supply the range of the various parameters that can be selected on.

casa::MSSelector::MSSelector ( const MSSelector & other )

Copy constructor, this will initialize the MS with other's MS.

casa::MSSelector::~MSSelector ( )

Member Function Documentation

Bool casa::MSSelector::checkSelection ( ) [protected]

check if the data description selection has been done & do default selection if not.

Return False if the selection fails.

Vector< Int > casa::MSSelector::dataDescId ( ) const [inline]

Return the data desc IDs selected.

Definition at line 324 of file MSSelector.h.

References dataDescId_p.

void casa::MSSelector::getAveragedData	(	Array< Complex > &	avData,
		const Array< Bool > &	flag,
		const ArrayColumn< Complex > &	col
	)		const `[protected]`

average and convert data

void casa::MSSelector::getAveragedData	(	Array< Float > &	avData,
		const Array< Bool > &	flag,
		const ArrayColumn< Float > &	col
	)		const `[protected]`

average and convert float data

void casa::MSSelector::getAveragedData	(	Array< Complex > &	avData,
		const Array< Bool > &	flag,
		const ArrayColumn< Complex > &	col,
		const Slicer &	rowSlicer
	)		const `[protected]`

average and convert data, with row Slicer

void casa::MSSelector::getAveragedData	(	Array< Float > &	avData,
		const Array< Bool > &	flag,
		const ArrayColumn< Float > &	col,
		const Slicer &	rowSlicer
	)		const `[protected]`

average and convert float data, with row Slicer

Array<Bool> casa::MSSelector::getAveragedFlag	(	Array< Bool > &	avFlag,
		const ArrayColumn< Bool > &	col
	)		const `[protected]`

"average" flag, at present all output which has a flagged input is flagged

Array<Bool> casa::MSSelector::getAveragedFlag	(	Array< Bool > &	avFlag,
		const ArrayColumn< Bool > &	col,
		const Slicer &	rowSlicer
	)		const `[protected]`

"average" flag, at present all output which has a flagged input is flagged, with row Slicer

Record casa::MSSelector::getData	(	const Vector< String > &	items,
		Bool	ifrAxis,
		Int	ifrAxisGap = `0`,
		Int	inc = `1`,
		Bool	average = `False`,
		Bool	oneBased = `False`
	)

Return the data for the items requested, all returned values will be arrays, the last dimension of these is the table row number.

The data arrays are normally 3D with axes: polarization, frequency, row. If ifrAxis is set to True, the data arrays returned will be 4D, with the data being split out along an extra interferometer axis, the axes will be: polarization, frequency, interferometer and time. Missing interferometers will be marked flagged. The order of the interferometers is that specified by the last select call. Add a (flagged) gap in the data at every antenna1 change if ifrAxisGap>0. Use inc > 1 to return data from every inc'th row. Use average=True to vector average the data along the row or time axis taking the weights column into account (use selectChannel to average channels together as well). Note that different interferometers will be averaged together if ifrAxis is False. Correct for one-based indexing if oneBased is True.

Array<Float> casa::MSSelector::getWeight	(	const ArrayColumn< Float > &	wtCol,
		Bool	sigma = `False`
	)		const `[protected]`

get the weight, set sigma=True when retrieving sigma's

Bool casa::MSSelector::initSelection	(	const Vector< Int > &	dataDescIds,
		Bool	reset = `False`
	)

initialize the selection by specifying, optionally, the DATA_DESC_IDs.

If you don't specify the dataDescIds and the data shape is constant all data is selected, if the shape does change, only the first dataDescId is selected. If you specify a number of dataDescIds and they all have the same shape, they are all selected, otherwise only the first is selected. The function returns false if the selection was limited due to changing data shape. Use the reset argument to return to the completely unselected ms.

Bool casa::MSSelector::initSelection ( Bool reset = False )

As above without the data desc id argument.

Bool casa::MSSelector::iterEnd ( )

End the iteration (before reaching the last iteration)

and set the selection back to the state before iteration started.

Bool casa::MSSelector::iterInit	(	const Vector< String > &	columns,
		Double	interval,
		Int	maxRows = `0`,
		Bool	addDefaultSortColumns = `True`
	)

Set up an iterator, iterating over the specified columns, with optional time interval and maximum number of rows to return at once (the default of zero returns all rows).

To keep MSIter from adding the default sort columns, specify addDefaultSortColumns=False

Bool casa::MSSelector::iterNext ( )

Step the iterator, sets the selection to the current table iteration.

Returns false if there is no more data and sets the selection back to the state before iteration started.

Bool casa::MSSelector::iterOrigin ( )

(Re)Set the iterator to the first iteration, call this after iterInit.

void casa::MSSelector::makeSlicer	(	Int	start,
		Int	nCorr
	)		const `[protected]`

make the data slicer, pass in the first and the number of correlations to select

Int casa::MSSelector::nrow ( ) const [inline]

Number of rows in selected table.

Definition at line 323 of file MSSelector.h.

References casa::Table::nrow(), and selms_p.

MSSelector& casa::MSSelector::operator= ( const MSSelector & other )

Assignment, this will initialize the MS with other's MS.

void casa::MSSelector::putAveragedFlag	(	const Array< Bool > &	avFlag,
		ArrayColumn< Bool > &	col
	)		`[protected]`

"unaverage" flag, distribute the flags back to the channels that went into the average

Bool casa::MSSelector::putData ( const Record & items )

Put the data for the items provided.

Note that only fields corresponding to actual table columns can be put (i.e., no AMPLITUDEs, IFR_NUMBERs etc) The data will need to have the correct shape for the column and a last dimension matching the number of selected rows (or last two dimensions matching times and interferometers, for data retrieved with ifraxis=T) Channel selection is supported, but the width parameter has to be 1.

void casa::MSSelector::reorderFlagRow ( Array< Bool > & flagRow ) [protected]

reorder from 2d to 1d (removing ifr axis)

void casa::MSSelector::reorderWeight ( Array< Float > & weight ) [protected]

reorder from 2d to 1d (removing ifr axis)

Bool casa::MSSelector::select	(	const Record &	items,
		Bool	oneBased = `False`
	)

Select the MS based on the selections present in the input record.

The format of this record is the same as that returned by range. Not all possible items can be selected on, some are quietly ignored. Correct for one-based indexing if oneBased is True.

Bool casa::MSSelector::select ( const String & msSelect )

Select the MS based on the TaQL selection string.

Bool casa::MSSelector::selectChannel	(	Int	nChan,
		Int	start,
		Int	width,
		Int	incr
	)

Set the mapping from input channels in the DATA column to output channels.

nChan is the number of output channels, start is the first channel to use, width specifies how wide a block of channels to average, increment specifies the start of the next block relative to the start of the current block. Note: averaging uncalibrated data should be avoided (no bandpass applied)

Bool casa::MSSelector::selected ( ) const [inline]

Return the selection status of the table.

Definition at line 326 of file MSSelector.h.

References initSel_p.

Table casa::MSSelector::selectedTable ( ) const [inline]

Return the selected table.

Definition at line 325 of file MSSelector.h.

References selms_p.

Bool casa::MSSelector::selectPolarization ( const Vector< String > & wantedPol )

Specify the output polarization.

Missing input polarizations are assumed to be zero. This selection/conversion assumes that parallactic angle rotation is taken care of elsewhere (i.e., results may only be correct for CORRECTED_DATA and MODEL_DATA conversions, not for the observed DATA)

void casa::MSSelector::setMS ( MeasurementSet & ms )

Change or Set the MS this MSSelector refers to.

void casa::MSSelector::timeAverage	(	Array< Bool > &	dataFlags,
		Array< Complex > &	data,
		const Array< Bool > &	flags,
		const Array< Float > &	weights
	)		`[protected]`