ObitOTFGrid.c File Reference

ObitOTFGrid class function definitions. More...

#include <math.h>
#include "ObitOTFGrid.h"
#include "ObitOTFSel.h"
#include "ObitFArrayUtil.h"
#include "ObitImageUtil.h"

Defines
#define	DG2RAD   G_PI / 180.0
	Degrees to radians factor.
#define	RAD2DG   180.0 / G_PI
	Radians to degrees factor.
#define	VELIGHT   2.997924562e8
	Velocity of light.
Functions
void	ObitOTFGridInit (gpointer in)
	Private: Initialize newly instantiated object.
void	ObitOTFGridClear (gpointer in)
	Private: Deallocate members.
ObitOTFGrid *	newObitOTFGrid (gchar *name)
	Public: Constructor.
gconstpointer	ObitOTFGridGetClass (void)
	Public: ClassInfo pointer.
void	ObitOTFGridSetup (ObitOTFGrid *in, ObitOTF *OTFin, ObitImageDesc *imageDesc, ObitErr *err)
	Public: initialize/reset ObitOTFGrid structures.
void	ObitOTFGridReadOTF (ObitOTFGrid *in, ObitOTF *OTFin, ObitErr *err)
	Public: Read uv data accumulating to grid.
void	ObitOTFGridNorm (ObitOTFGrid *in, ObitFArray *array, ObitImageDesc *imageDesc, ObitErr *err)
	Public: Normalize image grid with weight grid.
void	ObitOTFGridMakeBeam (ObitOTFGrid *in, ObitImage *image, ObitImage *Beam, ObitErr *err)
	Public: Make PSF ("Beam").
void	ObitOTFGridClassInit (void)
	Public: Class initializer.

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Detailed Description

ObitOTFGrid class function definitions.

GBT/OTF data class for gridding data into an image This class is derived from the Obit base class.

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Define Documentation

#define DG2RAD   G_PI / 180.0

Degrees to radians factor.

#define RAD2DG   180.0 / G_PI

Radians to degrees factor.

#define VELIGHT   2.997924562e8

Velocity of light.

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Function Documentation

ObitOTFGrid* newObitOTFGrid (  gchar *  name  )

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

void ObitOTFGridClassInit (  void   )

Public: Class initializer.

void ObitOTFGridClear (  gpointer  inn  )

Private: Deallocate members. Does (recursive) deallocation of parent class members. For some reason this wasn't build into the GType class. Parameters: inn  Pointer to the object to deallocate. Actually it should be an ObitOTFGrid* cast to an Obit*.

gconstpointer ObitOTFGridGetClass (  void   )

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

void ObitOTFGridInit (  gpointer  inn  )

Private: Initialize newly instantiated object. Parent classes portions are (recursively) initialized first Parameters: inn  Pointer to the object to initialize.

void ObitOTFGridMakeBeam (  ObitOTFGrid *  in, ObitImage *  image, ObitImage *  Beam, ObitErr *  err )

Public: Make PSF ("Beam"). The instrumental response including the convolving function is calculated and left as the "myBeam" of image. Parameters: in  Gridding object with input beam size and Convolving fn. Info includes: "beamNx" OBIT_int scalar Number of "x" pixels [def 32] "beamNy" OBIT_int scalar Number of "y" pixels [def 32] image  Image to attach beam to, Also fills in Beam size Beam  If non NULL use as instrumental response beam err  ObitErr stack for reporting problems.

void ObitOTFGridNorm (  ObitOTFGrid *  in, ObitFArray *  array, ObitImageDesc *  imageDesc, ObitErr *  err )

Public: Normalize image grid with weight grid. Requires setup by #ObitOTFGridCreate and gridding by ObitOTFGridReadOTF. Parameters: in  Object to initialize array  Output image array. imageDesc  Descriptor for image to be derived. Beam size corrected for effects of gridding convolution. err  ObitErr stack for reporting problems.

void ObitOTFGridReadOTF (  ObitOTFGrid *  in, ObitOTF *  OTFin, ObitErr *  err )

Public: Read uv data accumulating to grid. Buffering of data will use the buffers as defined on OTFin ("nRecPIO" in info member). The OTFin object will be closed at the termination of this routine. Requires setup by #ObitOTFGridCreate. Parameters: in  Gridding Object OTFin  OTF data object to be gridded. Should be the same as passed to previous call to ObitOTFGridSetup for input in. err  ObitErr stack for reporting problems.

void ObitOTFGridSetup (  ObitOTFGrid *  in, ObitOTF *  OTFin, ObitImageDesc *  imageDesc, ObitErr *  err )

Public: initialize/reset ObitOTFGrid structures. Input data should be fully edited and calibrated. The object OTFin will be opened during this call if it is not already open. The output image should describe the center, size and grid spacing of the desired image. The gridding information should have been stored in the ObitInfoList on in: "ConvType" OBIT_int scalar = Convolving function type: [def=3] 0 = pillbox, 3 = Gaussian, 4 = Exp*Sinc, 5 = Spherodial wave "ConvParm" OBIT_float[10] = Convolving function parameters "minWt" OBIT_float scalar = min. summed convolution weights to accept a pixel. Default = 0.1. Gridding convolution functions: 0 = pillbox, 2 = Sinc, Parm[0] = halfwidth in cells, Parm[1] = Expansion factor 3 = Gaussian, Parm[0] = halfwidth in cells,[def 3.0] Parm[1] = Gaussian with as fraction or raw beam [def 1.0] 4 = Exp*Sinc Parm[0] = halfwidth in cells, [def 2.0] Parm[1] = 1/sinc factor (cells) [def 1.55] Parm[2] = 1/exp factor (cells) [def 2.52] Parm[3] = exp power [def 2.0] 5 = Spherodial wave Parm[0] = halfwidth in cells [def 3.0] Parm[1] = Alpha [def 5.0] Parm[2] = Expansion factor [not used] Parameters: in  Object to initialize OTFin  Uv data object to be gridded. imageDesc  Descriptor for image to be derived. err  ObitErr stack for reporting problems.

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