ObitUVWeight.h File Reference

ObitUVWeight uv data class definition. More...

#include "Obit.h"
#include "ObitErr.h"
#include "ObitThread.h"
#include "ObitInfoList.h"
#include "ObitUV.h"
#include "ObitFArray.h"
#include "ObitDef.h"
#include "ObitClassDef.h"

Go to the source code of this file.

Classes
struct	ObitUVWeight
	ObitUVWeight Class structure. More...
struct	ObitUVWeightClassInfo
	ClassInfo Structure. More...
Typedefs
typedef void(*	ObitUVWeightDataFP )(ObitUV *uvdata, ObitErr *err)
Functions
void	ObitUVWeightClassInit (void)
	Public: Class initializer.
ObitUVWeight *	newObitUVWeight (gchar *name)
	Public: Constructor.
gconstpointer	ObitUVWeightGetClass (void)
	Public: ClassInfo pointer.
void	ObitUVWeightData (ObitUV *uvdata, ObitErr *err)
	Public: Determine weighting and correct an ObitUV.

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Detailed Description

ObitUVWeight uv data class definition.

This class is derived from the Obit class.

This class is for weighting uv data in preparation for imaging. Uniform, Natural and Briggs Robust weighting are supported. No instances of this class should be needed outside of the ObitUVWeightData function.

ObitUVWeightData convolves UV weights onto a grid to determine weighting function. Then the data weights are modified by the weighting function. The control parameters are attached to the ObitInfoList member info on uvdata. The parameters are:

• "nuGrid" OBIT_int scalar = Number of "U" pixels in weighting grid. [defaults to "nx"]
• "nvGrid" OBIT_int scalar = Number of "V" pixels in weighting grid.
• "WtBox" OBIT_int scalar = Size of weighting box in cells [def 0]
• "WtFunc" OBIT_int scalar = 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 scalar = Image cell spacing in X in asec.
• "yCells" OBIT_float scalar = Image cell spacing in Y in asec.
• "UVTaper"OBIT_float scalar = UV taper width in kilowavelengths. [def. no taper]. NB: If the taper is applied her is should not also be applied in the imaging step as the taper will be applied to the output data.
• "Robust" OBIT_float scalar = 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 scalar = 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 determing weights as well as after.
• "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.

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Typedef Documentation

typedef void(* ObitUVWeightDataFP)(ObitUV *uvdata, ObitErr *err)

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Function Documentation

ObitUVWeight* newObitUVWeight (  gchar *  name  )

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

void ObitUVWeightClassInit (  void   )

Public: Class initializer.

void ObitUVWeightData (  ObitUV *  uvdata, ObitErr *  err )

Public: Determine weighting and correct an ObitUV. Then the data weights are modified by the weighting function. The control parameters are attached to the ObitInfoList member info on uvdata. See ObitUVWeight class documentation for details

gconstpointer ObitUVWeightGetClass (  void   )

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

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