ObitUVImager.h File Reference

ObitUVImager Class for imaging UV data. More...

#include "Obit.h"
#include "ObitErr.h"
#include "ObitUV.h"
#include "ObitImageMosaic.h"

Go to the source code of this file.

Classes
struct	ObitUVImager
	ObitUVImager Class structure. More...
struct	ObitUVImagerClassInfo
	ClassInfo Structure. More...
Defines
#define	ObitUVImagerUnref(in)   ObitUnref (in)
	Macro to unreference (and possibly destroy) an ObitUVImager returns a ObitUVImager*.
#define	ObitUVImagerRef(in)   ObitRef (in)
	Macro to reference (update reference count) an ObitUVImager.
#define	ObitUVImagerIsA(in)   ObitIsA (in, ObitUVImagerGetClass())
	Macro to determine if an object is the member of this or a derived class.
Typedefs
typedef ObitUVImager *(*	ObitUVImagerCreateFP )(gchar *name, ObitUV *uvdata, ObitErr *err)
	Typedef for definition of class pointer structure.
typedef ObitUVImager *(*	ObitUVImagerCreate2FP )(gchar *name, ObitUV *uvdata, ObitImageMosaic *mosaic, ObitErr *err)
	Typedef for definition of class pointer structure.
typedef void(*	ObitUVImagerWeightFP )(ObitUVImager *in, ObitErr *err)
	Typedef for definition of class pointer structure.
typedef void(*	ObitUVImagerImageFP )(ObitUVImager *in, glong field, gboolean doWeight, gboolean doBeam, gboolean doFlatten, ObitErr *err)
	Typedef for definition of class pointer structure.
typedef void(*	ObitUVImagerFlattenFP )(ObitUVImager *in, ObitErr *err)
	Typedef for definition of class pointer structure.
typedef ObitImageMosaic *(*	ObitUVImagerGetMosaicFP )(ObitUVImager *in, ObitErr *err)
	Typedef for definition of class pointer structure.
Functions
void	ObitUVImagerClassInit (void)
	Public: Class initializer.
ObitUVImager *	newObitUVImager (gchar *name)
	Public: Default Constructor.
gconstpointer	ObitUVImagerGetClass (void)
	Public: ClassInfo pointer.
ObitUVImager *	ObitUVImagerCopy (ObitUVImager *in, ObitUVImager *out, ObitErr *err)
	Public: Copy (deep) constructor.
void	ObitUVImagerClone (ObitUVImager *in, ObitUVImager *out, ObitErr *err)
	Public: Copy structure.
ObitUVImager *	ObitUVImagerCreate (gchar *name, ObitUV *uvdata, ObitErr *err)
	Public: Create/initialize ObitUVImager structures.
ObitUVImager *	ObitUVImagerCreate2 (gchar *name, ObitUV *uvdata, ObitImageMosaic *mosaic, ObitErr *err)
	Public: Create/initialize ObitUVImager structures given mosaic.
void	ObitUVImagerWeight (ObitUVImager *in, ObitErr *err)
	Public: Weight data.
void	ObitUVImagerImage (ObitUVImager *in, glong field, gboolean doWeight, gboolean doBeam, gboolean doFlatten, ObitErr *err)
	Public: Form Image.
void	ObitUVImagerFlatten (ObitUVImager *in, ObitErr *err)
	Public: Flatten.
ObitImageMosaic *	ObitUVImagerGetMosaic (ObitUVImager *in, ObitErr *err)
	Public: return ImageMosaic member.

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Detailed Description

ObitUVImager Class for imaging UV data.

This class is derived from the Obit class.

This class presents a uniform interface to the UV data imaging routines. These go from an input uv data and allow optional selection, calibration and editing and then conversion into a dirty image allowing a number of processing parameters. The result is an ImageMosaic which may optionally be flattened into a single plane.

Creators and Destructors

An ObitUVImager will usually be created using ObitUVImagerCreate which allows specifying a name for the object as well as other information.

A copy of a pointer to an ObitUVImager should always be made using the ObitUVImagerRef function which updates the reference count in the object. Then whenever freeing an ObitUVImager or changing a pointer, the function ObitUVImagerUnref will decrement the reference count and destroy the object when the reference count hits 0. There is no explicit destructor.

Control Parameters

The imaging control parameters are passed through the info object on the uv data, these control both the output image files and the processing parameters. Output images:

• "Type OBIT_int (1,1,1) Underlying file type, 1=FITS, 2=AIPS
• "Name" OBIT_string (?,1,1) Name of image, used as AIPS name or to derive FITS filename
• "Class" OBIT_string (?,1,1) Root of class, used as AIPS class or to derive FITS filename
• "Seq" OBIT_int (1,1,1) Sequence number
• "Disk" OBIT_int (1,1,1) Disk number for underlying files

UVData selection/calibration/editing control

• "MaxBaseline" OBIT_float scalar = maximum baseline length in wavelengths. Default = 1.0e15. Output data not flagged by this criteria.
• "MinBaseline" OBIT_float scalar = minimum baseline length in wavelengths. Default = 1.0e15.Output data not flagged by this criteria.
• "doCalSelect" OBIT_bool (1,1,1) Select/calibrate/edit data?
• "Stokes" OBIT_string (4,1,1) Selected output Stokes parameters: " "=> no translation,"I ","V ","Q ", "U ", "IQU ", "IQUV", "IV ", "RR ", "LL ", "RL ", "LR ", "HALF" = RR,LL, "FULL"=RR,LL,RL,LR. [default " "] In the above 'F' can substitute for "formal" 'I' (both RR+LL).
• "BChan" OBIT_int (1,1,1) First spectral channel selected. [def all]
• "EChan" OBIT_int (1,1,1) Highest spectral channel selected. [def all]
• "BIF" OBIT_int (1,1,1) First "IF" selected. [def all]
• "EIF" OBIT_int (1,1,1) Highest "IF" selected. [def all]
• "doPol" OBIT_int (1,1,1) >0 -> calibrate polarization.
• "doCalib" OBIT_int (1,1,1) >0 -> calibrate, 2=> also calibrate Weights
• "gainUse" OBIT_int (1,1,1) SN/CL table version number, 0-> use highest
• "flagver" OBIT_int (1,1,1) Flag table version, 0-> use highest, <0-> none
• "BLVer" OBIT_int (1,1,1) BL table version, 0> use highest, <0-> none
• "BPVer" OBIT_int (1,1,1) Band pass (BP) table version, 0-> use highest
• "Subarray" OBIT_int (1,1,1) Selected subarray, <=0->all [default all]
• "freqID" OBIT_int (1,1,1) Selected Frequency ID, <=0->all [default all]
• "timeRange" OBIT_float (2,1,1) Selected timerange in days.
• "UVRange" OBIT_float (2,1,1) Selected UV range in kilowavelengths.
• "Sources" OBIT_string (?,?,1) Source names selected unless any starts with a '-' in which cse all are deselected (with '-' stripped).
• "Antennas" OBIT_int (?,1,1) a list of selected antenna numbers, if any is negative then the absolute values are used and the specified antennas are deselected.
• "corrType" OBIT_int (1,1,1) Correlation type, 0=cross corr only, 1=both, 2=auto only.
• "doBand" OBIT_int (1,1,1) Band pass application type <0-> none (1) if = 1 then all the bandpass data for each antenna will be averaged to form a composite bandpass spectrum, this will then be used to correct the data. (2) if = 2 the bandpass spectra nearest in time (in a weighted sense) to the uv data point will be used to correct the data. (3) if = 3 the bandpass data will be interpolated in time using the solution weights to form a composite bandpass spectrum, this interpolated spectrum will then be used to correct the data. (4) if = 4 the bandpass spectra nearest in time (neglecting weights) to the uv data point will be used to correct the data. (5) if = 5 the bandpass data will be interpolated in time ignoring weights to form a composite bandpass spectrum, this interpolated spectrum will then be used to correct the data.
• "Smooth" OBIT_float (3,1,1) specifies the type of spectral smoothing Smooth(1) = type of smoothing to apply: 0 => no smoothing 1 => Hanning 2 => Gaussian 3 => Boxcar 4 => Sinc (i.e. sin(x)/x) Smooth(2) = the "diameter" of the function, i.e. width between first nulls of Hanning triangle and sinc function, FWHM of Gaussian, width of Boxcar. Defaults (if < 0.1) are 4, 2, 2 and 3 channels for Smooth(1) = 1 - 4. Smooth(3) = the diameter over which the convolving function has value - in channels. Defaults: 1, 3, 1, 4 times Smooth(2) used when

Imaging parameters:

• "FOV" OBIT_float (1,1,1) Field of view (deg) for Mosaic If > 0.0 then a mosaic of images will be added to cover this region. Note: these are in addition to the NField fields added by other parameters
• "doFull" OBIT_boolean (1,1,1) if TRUE, create full field image to cover FOV [def. FALSE]
• "NField" OBIT_int (1,1,1) Number of fields defined in input, if unspecified derive from data and FOV
• "xCells" OBIT_float (?,1,1) Cell spacing in X (asec) for all images, if unspecified derive from data
• "yCells" OBIT_float (?,1,1) Cell spacing in Y (asec) for all images, if unspecified derive from data
• "nx" OBIT_int (?,1,1) Minimum number of cells in X for NField images if unspecified derive from data
• "ny" OBIT_int (?,1,1) Minimum number of cells in Y for NField images if unspecified derive from data
• "RAShift" OBIT_float (?,1,1) Right ascension shift (AIPS convention) for each field if unspecified derive from FOV and data
• "DecShift" OBIT_float (?,1,1) Declination for each field if unspecified derive from FOV and data

Outliers to be added:

• "Catalog" OBIT_string (?,1,1) = AIPSVZ format catalog for defining outliers, 'None'=don't use [default] 'Default' = use default catalog. Assumed in FITSdata disk 1.
• "OutlierDist" OBIT_float (1,1,1) Maximum distance (deg) from center to include outlier fields from Catalog. [default 1 deg]
• "OutlierFlux" OBIT_float (1,1,1) Minimum estimated flux density include outlier fields from Catalog. [default 0.1 Jy ]
• "OutlierSI" OBIT_float (1,1,1) Spectral index to use to convert catalog flux density to observed frequency. [default = -0.75]
• "OutlierSize" OBIT_int (?,1,1) Width of outlier field in pixels. [default 50]

Weighting parameters on inUV:

• "nuGrid" OBIT_int (1,1,1) = Number of "U" pixels in weighting grid. [defaults to "nx"]
• "nvGrid" OBIT_int (1,1,1) Number of "V" pixels in weighting grid.
• "WtBox" OBIT_int (1,1,1) Size of weighting box in cells [def 1]
• "WtFunc" OBIT_int (1,1,1) Weighting convolution function [def. 1] 1=Pill box, 2=linear, 3=exponential, 4=Gaussian if positive, function is of radius, negative in u and v.
• "xCells" OBIT_float (1,1,1) Image cell spacing in X in asec.
• "yCells" OBIT_float (1,1,1) Image cell spacing in Y in asec.
• "UVTaper" OBIT_float (1,1,1) UV taper width in kilowavelengths. [def. no taper]. NB: If the taper is applied here is should not also be applied in the imaging step as the taper will be applied to the output data.
• "Robust" OBIT_float (1,1,1) Briggs robust parameter. [def. 0.0] < -7 -> Pure Uniform weight, >7 -> Pure natural weight. Uses AIPS rather than Briggs definition of Robust.
• "WtPower" OBIT_float (1,1,1) Power to raise weights to. [def = 1.0] Note: a power of 0.0 sets all the output weights to 1 as modified by uniform/Tapering weighting. Applied in determinng weights as well as after.

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Define Documentation

#define ObitUVImagerIsA (  in   )     ObitIsA (in, ObitUVImagerGetClass())

Macro to determine if an object is the member of this or a derived class. Returns TRUE if a member, else FALSE in = object to reference

#define ObitUVImagerRef (  in   )     ObitRef (in)

Macro to reference (update reference count) an ObitUVImager. returns a ObitUVImager*. in = object to reference

#define ObitUVImagerUnref (  in   )     ObitUnref (in)

Macro to unreference (and possibly destroy) an ObitUVImager returns a ObitUVImager*. in = object to unreference

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Typedef Documentation

typedef ObitUVImager*(* ObitUVImagerCreate2FP)(gchar *name, ObitUV *uvdata, ObitImageMosaic *mosaic, ObitErr *err)

Typedef for definition of class pointer structure.

typedef ObitUVImager*(* ObitUVImagerCreateFP)(gchar *name, ObitUV *uvdata, ObitErr *err)

Typedef for definition of class pointer structure.

typedef void(* ObitUVImagerFlattenFP)(ObitUVImager *in, ObitErr *err)

Typedef for definition of class pointer structure.

typedef ObitImageMosaic*(* ObitUVImagerGetMosaicFP)(ObitUVImager *in, ObitErr *err)

Typedef for definition of class pointer structure.

typedef void(* ObitUVImagerImageFP)(ObitUVImager *in, glong field, gboolean doWeight, gboolean doBeam, gboolean doFlatten, ObitErr *err)

Typedef for definition of class pointer structure.

typedef void(* ObitUVImagerWeightFP)(ObitUVImager *in, ObitErr *err)

Typedef for definition of class pointer structure.

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Function Documentation

ObitUVImager* newObitUVImager (  gchar *  name  )

Public: Default Constructor. Initializes class if needed on first call. Parameters: name  An optional name for the object. Returns: the new object.

void ObitUVImagerClassInit (  void   )

Public: Class initializer.

void ObitUVImagerClone (  ObitUVImager *  in, ObitUVImager *  out, ObitErr *  err )

Public: Copy structure. Parameters: in  The object to copy out  An existing object pointer for output, must be defined. err  Obit error stack object.

ObitUVImager* ObitUVImagerCopy (  ObitUVImager *  in, ObitUVImager *  out, ObitErr *  err )

Public: Copy (deep) constructor. Parameters: in  The object to copy out  An existing object pointer for output or NULL if none exists. err  Obit error stack object. Returns: pointer to the new object.

ObitUVImager* ObitUVImagerCreate (  gchar *  name, ObitUV *  uvdata, ObitErr *  err )

Public: Create/initialize ObitUVImager structures. The output ImageMosaic member is created Parameters: name  An optional name for the object. uvdata  ObitUV object with info member containng the output image specifications and all processing parameters. err  Obit error stack object. Returns: the new object.

ObitUVImager* ObitUVImagerCreate2 (  gchar *  name, ObitUV *  uvdata, ObitImageMosaic *  mosaic, ObitErr *  err )

Public: Create/initialize ObitUVImager structures given mosaic. Parameters: name  An optional name for the object. uvdata  ObitUV object with info member containng the output image specifications and all processing parameters. mosaic  ImageMosaic to use err  Obit error stack object. Returns: the new object.

void ObitUVImagerFlatten (  ObitUVImager *  in, ObitErr *  err )

Public: Flatten. Parameters: in  The input object err  Obit error stack object.

gconstpointer ObitUVImagerGetClass (  void   )

Public: ClassInfo pointer. Returns: pointer to the class structure.

ObitImageMosaic* ObitUVImagerGetMosaic (  ObitUVImager *  in, ObitErr *  err )

Public: return ImageMosaic member. Parameters: in  The input object err  Obit error stack object. Returns: reference to ImageMosaic.

void ObitUVImagerImage (  ObitUVImager *  in, glong  field, gboolean  doWeight, gboolean  doBeam, gboolean  doFlatten, ObitErr *  err )

Public: Form Image. Parameters: in  The input object field  Which field (1-rel) to Image, 0=> all doWeight  If TRUE do Weighting ov uv data first If TRUE then input data is modified. doBeam  If True calculate dirst beams first doFlatten  If TRUE, flatten images when done err  Obit error stack object.

void ObitUVImagerWeight (  ObitUVImager *  in, ObitErr *  err )

Public: Weight data. Parameters: in  The input object err  Obit error stack object.

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