Attempts to reconstruct the shear bias map from an image of the field. This module measures the moments of each galaxy object (the locations of which must be provided). Then, the shear bias of all objects within a square subwindow of the image is calculated, and this value is stored as a pixel in an output map. The window is moved slightly (usually by less than the width of the window), and the measurement is repeated. The final map is placed in the data stream.

If the AlsoIdeal keyword is set, the module also produces the "ideal" reconstruction, which is the true shear map convolved with the window response function. This would be the result map if each window were perfectly sampled.

Currently only the shapelet method of bias measurement is included. This necessitates an additional source of "background" galaxies which do not contain the shear bias. This is provided by an additional input of a galaxy set. Once non-shapelet methods are included, this won't be necessary.

Parameters

Name	Type	Description
WindowSize	int	Pixel width of window to consider for each shear measurement.
WindowStep	int	Number of pixels to shift the window for each measurement.
BufSize	int	Pixel width of holding buffer to use when calculating moments of galaxies.
NumCoeff	int	Number of shapelet coefficients to use.
Beta	double	Scale function to use when decomposing objects into shapelet coefficients.
NeighborRejection	keyword	If set, ignore any objects whose centroid is within 3.2*Beta of the centroid of any other object.
AlsoIdeal	keyword	If set, also produces an "idealized" reconstruction of the original shear field, as described above.
ShearTag	string	If AlsoIdeal is set, the name of the original shear field model must be provided.
Verbose	keyword	If set, write debugging information to cout.

Inputs

Name	Type	Description
Image/Data	double*	Pixel value array.
Image/Width	int	Pixel width of the image.
Image/Height	int	Pixel height of the image.
Image/ObjectX	double*	Array of x-coordinates of objects, in pixel units.
Image/ObjectY	double*	Array of y-coordinates of objects, in pixel units.
Image/ObjectTypes	int*	Array of types of objects, as specified in SimConst.h
Image/NumberObjs	int	Number of objects placed in image. This will be the length of the above arrays.
GalSet/ShapeletMean	double*	Single shapelet decomposition of the average unbiased galaxy.

Outputs

Name	Type	Description
ShearMap/Gamma1	double*	A two-dimensional array of the measurements of Gamma1 for each sample window calculated from the image..
ShearMap/Gamma2	double*	A two-dimensional array of the measurements of Gamma2 for each sample window calculated from the image.
ShearMap/IdealGamma1	double*	A two-dimensional array of the measurements of Gamma1 for each sample window in the idealized case.
ShearMap/IdealGamma2	double*	A two-dimensional array of the measurements of Gamma2 for each sample window in the idealized case.
ShearMap/NumXSamples	int	Number of measured samples in the X dimension.
ShearMap/NumYSamples	int	Number of measured samples in the Y dimension.