DecorrelateALKernelSpatialTask

class lsst.ip.diffim.DecorrelateALKernelSpatialTask(*args, **kwargs)

Bases: Task

Decorrelate the effect of convolution by Alard-Lupton matching kernel in image difference

Methods Summary

computeVarianceMean(exposure)	Compute the mean of the variance plane of exposure.
run(scienceExposure, templateExposure, ...)	Perform decorrelation of an image difference exposure.

Methods Documentation

computeVarianceMean(exposure)

Compute the mean of the variance plane of exposure.

run(scienceExposure, templateExposure, subtractedExposure, psfMatchingKernel, spatiallyVarying=True, preConvKernel=None, templateMatched=True, preConvMode=False)

Perform decorrelation of an image difference exposure.

Decorrelates the diffim due to the convolution of the templateExposure with the A&L psfMatchingKernel. If spatiallyVarying is True, it utilizes the spatially varying matching kernel via the imageMapReduce framework to perform spatially-varying decorrelation on a grid of subExposures.

Parameters

scienceExposurelsst.afw.image.Exposure

the science Exposure used for PSF matching

templateExposurelsst.afw.image.Exposure

the template Exposure used for PSF matching

subtractedExposurelsst.afw.image.Exposure

the subtracted Exposure produced by ip_diffim.ImagePsfMatchTask.subtractExposures()

psfMatchingKernelan (optionally spatially-varying) PSF matching kernel produced

by ip_diffim.ImagePsfMatchTask.subtractExposures()

spatiallyVaryingbool

if True, perform the spatially-varying operation

preConvKernellsst.meas.algorithms.Psf

if not none, the scienceExposure has been pre-filtered with this kernel. (Currently this option is experimental.)

templateMatchedbool, optional

If True, the template exposure was matched (convolved) to the science exposure.

preConvModebool, optional

If True, subtractedExposure is assumed to be a likelihood difference image and will be noise corrected as a likelihood image.

Returns

resultslsst.pipe.base.Struct

a structure containing: - correctedExposure : the decorrelated diffim