MirVisReader Class Reference

a Miriad visibility dataset reader More...

#include <MirVisReader.h>

Inheritance diagram for MirVisReader:

Public Types
enum	wideConventions { NONE, BIMA, MIRIAD, MIXED, NCONV }
Public Member Functions
	MirVisReader (const String &mirfile, Bool doscan=True, Int dbg=0, Bool dopreview=True)
	construct a reader.
	~MirVisReader ()
	destroy the reader
void	setDebugLevel (Int level)
	set the debugging level which controls the amount of debugging messages that are printed to the terminal (as opposed to the logger).
Int	getDebugLevel () const
	set the debugging level which controls the amount of debugging messages that are printed to the terminal.
Bool	Debug (Int level)
	return true if the debugging level is at least as high as a given level.
const String &	getName ()
	return the Miriad dataset name
void	reset (MirVarHandler *filler=NULL, Bool verbose=False, Bool dowide=True, Int maxrec=0)
	rewind the input dataset and prepare for a new reading.
Int	readIntegration (::FillMetadata &fm)
	read in the data for a single timestamp.
Double	getTime ()
	return the (AIPS++-referenced) timestamp for the current buffered records.
Int	getNumRecs ()
	return the number of records buffered for the current integration
MirDataRecord *	getRecord (Int i)
	return the correlation data for the i-th buffered record.
void	clearMarks ()
	set the marked data item for each MirDataRecord to False
MirHisReader *	openHistory ()
	create and return a new pointer to a history reader.
ConstMirPolSetup &	getDefaultPolSetup ()
	return the basic characteristics of the input dataset as a Record.
const List< MirSource * > &	getSourceList ()
	return the list of sources
Protected Member Functions
void	preview (Int scanlim, Int obslim, Bool scan=True)
	peek into the contents of the dataset to cache important information.
void	preview (Bool scan=True)
	peek into the contents of the dataset to cache important information.
Bool	previewed ()
	return True if this dataset has been previewed
Private Member Functions
Bool	verbose ()
	return the basic characteristics of the input dataset as a Record.
void	checkIsMiriadDataset (const String &name) throw (AipsError)
	check to be sure that the given name points to a readable miriad dataset.
void	resizeBufferFor (Int nrec=0, Int nnarrow=0, Int nwide=0)
	resize the data buffer for a new read.
void	fullscan (Int scanlim, Int obslim)
	full and brief scanning of the data--should only be called from preview()
void	briefscan ()
void	handleVarChanges (::FillMetadata &fm, Double time)
	update the given FillMetadata container with updated variable values.
void	setTelescope (String name)
	add to a cached list of telescopes
Private Attributes
String	inname_p
	info that doesn't change during life of filler
Int	uv_handle_p
uInt	debug
LogIO	log_p
List< MirFreqSetup * >	fsetups_p
	variable information worth caching
List< MirSource * >	sources_p
List< String >	telescopes_p
MirPolSetup	pol_p
Int	maxchan_p
Int	maxwide_p
Int	maxspect_p
Int	narray_p
Int	nrec_p
Int	nobs_p
Int	nscan_p
Int	badnsyst_p
Int	badwsyst_p
Int	firstmode_p
Double	starttime_p
Double	endtime_p
wideConventions	wideconv_p
Block< MirDataRecord * >	buf_p
	read state
Int	nintrec_p
Int	maxrec_p
Int	nnarr_p
Int	nwide_p
Double	time_p
MirVarHandler *	varhandler_p
Bool	varupd_p
Bool	hasmore_p
Bool	dowide_p
Bool	verbose_p
Bool	previewed_p
Bool	scanned_p

Detailed Description

a Miriad visibility dataset reader

Intended use:

Public interface

Review Status

Date Reviewed:: yyyy/mm/dd

Etymology

Class name is short for Miriad visibility reader.

Motivation

MSes filled from Miriad data feature multiple windows of differing shapes. Performance during MS reads can be aided by collecting together MS table records of the same shape (e.g. of the same window). MirFiller accomplishes this by reading all baselines from a single timestamp at once, so that they written out in order of spectral window. This class provides a container for holding the data from different baselines. It also encapsulates all the knowledge needed for reading Miriad data.

Synopsis

This class is used to extract data from a Miriad visibility dataset.

Example

To Do

deal with telescopes, correlator modes
support multiple polarizations
make handleVarChanges() a protected virtual function

Definition at line 247 of file MirVisReader.h.

Member Enumeration Documentation

enum MirVisReader::wideConventions

Enumerator:

NONE
BIMA
MIRIAD
MIXED
NCONV

Definition at line 249 of file MirVisReader.h.

Constructor & Destructor Documentation

MirVisReader::MirVisReader	(	const String &	mirfile,
		Bool	doscan = `True`,
		Int	dbg = `0`,
		Bool	dopreview = `True`
	)

construct a reader.

mirfile is the name of Miriad dataset. If dopreview is False, the previewing of the dataset's contents will be delayed. If doscan is True (and dopreview is True), the entire input dataset will be read to take an accounting of its contents; set this to False to prevent this for a very large file (see also preview()). dbg is the default debug level to set; this value is passed to setDebugLevel().

MirVisReader::~MirVisReader ( )

destroy the reader

Member Function Documentation

void MirVisReader::briefscan ( ) [private]

void MirVisReader::checkIsMiriadDataset ( const String & name ) throw (AipsError) [private]

check to be sure that the given name points to a readable miriad dataset.

If not, throw an exception.

void MirVisReader::clearMarks ( ) [inline]

set the marked data item for each MirDataRecord to False

Definition at line 334 of file MirVisReader.h.

References buf_p, casacore::False, and nintrec_p.

Bool MirVisReader::Debug ( Int level ) [inline]

return true if the debugging level is at least as high as a given level.

Definition at line 305 of file MirVisReader.h.

References debug.

void MirVisReader::fullscan	(	Int	scanlim,
		Int	obslim
	)			`[private]`

full and brief scanning of the data--should only be called from preview()

Int MirVisReader::getDebugLevel ( ) const [inline]

set the debugging level which controls the amount of debugging messages that are printed to the terminal.

A value of zero or less means that no extra messages will be printed; increasing values will increase the amount of messages.

Definition at line 301 of file MirVisReader.h.

References debug.

ConstMirPolSetup& MirVisReader::getDefaultPolSetup ( ) [inline]

return the basic characteristics of the input dataset as a Record.

If scan is True, the entire file will be scanned (if necessary) to all the information; otherwise, an incomplete description may be given based on just the first record. If verbose is True, a summary is sent to the logger. Note that this function may force a call to preview() if it has not already been called. PJT GlishRecord summary(Bool verbose=True, Bool scan=True);

return the basic characteristics of the input dataset as a Record. A scanning of the entire file will be forced so that the number of scans and observations can be counted with the given limits: scanlim is the maximum time gap in seconds allowed between records of the same scan; obslim is maximum gap in seconds between records of the same observation. If verbose is True, a summary is sent to the logger. PJT GlishRecord summary(Int scanlim, Int obslim, Bool verbose=True);

get the full list of polarization correlation types seen thus far

Definition at line 360 of file MirVisReader.h.

References pol_p.

const String& MirVisReader::getName ( ) [inline]

return the Miriad dataset name

Definition at line 308 of file MirVisReader.h.

References inname_p.

Int MirVisReader::getNumRecs ( ) [inline]

return the number of records buffered for the current integration

Definition at line 328 of file MirVisReader.h.

References nintrec_p.

MirDataRecord* MirVisReader::getRecord ( Int i ) [inline]

return the correlation data for the i-th buffered record.

Definition at line 331 of file MirVisReader.h.

References buf_p.

const List<MirSource*>& MirVisReader::getSourceList ( ) [inline]

return the list of sources

Definition at line 363 of file MirVisReader.h.

References sources_p.

Double MirVisReader::getTime ( ) [inline]

return the (AIPS++-referenced) timestamp for the current buffered records.

This is only correct after a call to readIntegration().

Definition at line 325 of file MirVisReader.h.

References time_p.

void MirVisReader::handleVarChanges	(	::FillMetadata &	fm,
		Double	time
	)			`[private]`

update the given FillMetadata container with updated variable values.

If a VarHandler was provide via reset(), signal the changes to it. fm is the FillMetadata container to update, and time is the current timestamp.

MirHisReader* MirVisReader::openHistory ( ) [inline]

create and return a new pointer to a history reader.

The caller should delete the reader when finished with it.

Definition at line 340 of file MirVisReader.h.

References uv_handle_p.

void MirVisReader::preview ( Bool scan = True ) [inline, protected]

peek into the contents of the dataset to cache important information.

If scan is True (the default), the dataset will be read through to gather the information; otherwise, limited information will be gleaned from the first record. One can set scan=False for very large datasets to avoid this overhead. Five minutes and four hours are used for the scan and observation gap limit (when scan=True).

Definition at line 384 of file MirVisReader.h.

References preview().

Referenced by preview().

void MirVisReader::preview	(	Int	scanlim,
		Int	obslim,
		Bool	scan = `True`
	)			`[protected]`

peek into the contents of the dataset to cache important information.

scanlim and obslim are used for counting the number of observations and scans in the dataset. scanlim is the maximum time gap in seconds allowed between records of the same scan; obslim is maximum gap in seconds between records of the same observation. If scan is True (the default), the dataset will be read through to gather the information; otherwise, limited information will be gleaned from the first record and scanlim and obslim will be ignored. One can set scan=False for very large datasets to avoid this overhead.

Bool MirVisReader::previewed ( ) [inline, protected]

return True if this dataset has been previewed

Definition at line 387 of file MirVisReader.h.

References previewed_p.

Int MirVisReader::readIntegration ( ::FillMetadata & fm )

read in the data for a single timestamp.

fm is the container to use to store retrieved metadata.

void MirVisReader::reset	(	MirVarHandler *	filler = `NULL`,
		Bool	verbose = `False`,
		Bool	dowide = `True`,
		Int	maxrec = `0`
	)

rewind the input dataset and prepare for a new reading.

filler is the object that will handle updates to variables; if NULL, no handler will be alerted when variables change. If dowide is True, the wideband data will be read in, too. maxrec is the maximum number of records to read per timestamp; if maxrec<=0, it will adjust dynamically to the number of baselines being processed.

void MirVisReader::resizeBufferFor	(	Int	nrec = `0`,
		Int	nnarrow = `0`,
		Int	nwide = `0`
	)			`[private]`

resize the data buffer for a new read.

Values less than or equal to zero mean keep previous value.

void MirVisReader::setDebugLevel ( Int level ) [inline]

set the debugging level which controls the amount of debugging messages that are printed to the terminal (as opposed to the logger).

A value of zero or less will cause no extra messages to be printed; increasing values will increase the amount of messages.

Definition at line 295 of file MirVisReader.h.

References debug.

Referenced by MirFiller::setDebugLevel().

void MirVisReader::setTelescope ( String name ) [inline, private]

add to a cached list of telescopes

Definition at line 435 of file MirVisReader.h.

References telescopes_p.

Bool MirVisReader::verbose ( ) [inline, private]

return the basic characteristics of the input dataset as a Record.

If verbose is True, a summary is sent to the logger. scan specifies the conditions under which the entire dataset may get read as a result of this request: if scan < 0, the dataset will not be read; if scan=0, it will only be read if it hasn't already (using scanlim and obslim if necessary; if scan > 0, the dataset will be read and scanlim and obslim will be used to count scans and observations. scanlim is the maximum time gap in seconds allowed between records of the same scan; obslim is maximum gap in seconds between records of the same observation. GlishRecord summary(Bool verbose, Int scan, Int scanlim, Int obslim);

return the contents of a MirPolSetup list as a GlishArray static GlishArray toGlishArray(ConstMirPolSetup &pol);

return the contents of a String List as a GlishArray static GlishArray toGlishArray(const List<String>& list); return true if this reader should be verbose in its messages. This will be true if the verbose option is enabled or the debug level is greater than 1.

Definition at line 414 of file MirVisReader.h.

References debug, and verbose_p.