def setUp(self):
'''Create two calibs, one with a valid zero-point and one without. Use these to create two UnitSystem
objects.
'''
self.mag2Flux = lambda m: 10.0**(m/2.5)
self.flux2Mag = lambda f: 2.5*np.log10(f)
photoCalibNoZero = afwImage.PhotoCalib()
photoCalibWithZero = afwImage.makePhotoCalibFromCalibZeroPoint(self.mag2Flux(25))
scale = 0.2 * geom.arcseconds
wcs = afwGeom.makeSkyWcs(crpix=geom.Point2D(),
crval=geom.SpherePoint(45.0, 45.0, geom.degrees),
cdMatrix=afwGeom.makeCdMatrix(scale=scale))
self.unitNoZero = measModel.UnitSystem(wcs, photoCalibNoZero)
self.unitWithZero = measModel.UnitSystem(wcs, photoCalibWithZero)
def setUp(self):
'''Create two calibs, one with a valid zero-point and one without. Use these to create two UnitSystem
objects.
'''
self.mag2Flux = lambda m: 10.0**(m / 2.5)
self.flux2Mag = lambda f: 2.5 * np.log10(f)
calibNoZero = afwImage.Calib()
calibWithZero = afwImage.Calib()
calibWithZero.setFluxMag0(self.mag2Flux(25))
cdelt = (0.2 * afwGeom.arcseconds).asDegrees()
position = afwCoord.IcrsCoord(45.0 * afwGeom.degrees,
45.0 * afwGeom.degrees)
wcs = afwImage.makeWcs(position, afwGeom.Point2D(), cdelt, 0.0, 0.0,
cdelt)
self.unitNoZero = measModel.UnitSystem(wcs, calibNoZero)
self.unitWithZero = measModel.UnitSystem(wcs, calibWithZero)
def reconstructCModel(exposure, record, config):
""" Reconstruct the CModel for the given record
Parameters
----------
exposure : `lsst.afw.image.Exposure`
Exposure object that contains the source which was modeled
record : `lsst.afw.table.SourceRecord`
Record object which contains the measurements made on the source
config : `lsst.meas.modelfit.CModel(SingleFrame/Forced)Config`
Configuration object of the CModel plugin used in the measurement
process
Returns
-------
devShapelet : `lsst.shapelet.MultiShapeletFunction`
Multi-component shapelet model of the dev component of CModel
expShapelet : `lsst.shapelet.MultiShapeletFunction`
Multi-component shapelet model fo the exp component of CModel
devJointShapelet : `lsst.shapelet.MultiShapeletFunction`
Multi-component shapelet model of the dev component of CModel jointly
fit with the exp component
expJointShapelet : `lsst.shapelet.MultiShapeletFunction`
Multi-component shapelet model of the exp component of Cmodel jointly
fit with the dev component
"""
# build a unit system transformation object
center = record.getCentroid()
position = exposure.getWcs().pixelToSky(center)
measSys = measMod.UnitSystem(exposure)
approxFlux = record.get("base_PsfFlux_flux")
fitSys = measMod.UnitSystem(position, exposure.getCalib(), approxFlux)
fitSysToMeasSys = measMod.LocalUnitTransform(center, fitSys, measSys)
# Build the Shapelet objects
ctrl = config.makeControl()
baseName = "modelfit_CModel"
nonlinearKeys = [
"{}_{{model}}_nonlinear_{p}".format(baseName, p=p) for p in range(3)
]
fixedKeys = [
"{}_{{model}}_fixed_{p}".format(baseName, p=p) for p in range(2)
]
fluxKey = "{}_{{model}}_flux".format(baseName)
# fetch the aperture corrections, if this fails set it to one
try:
apCorr = record.get("{}_apCorr".format(baseName))
except Exception:
print("Warning, problem retrieving aperture correction, using a value"
" of 1")
apCorr = 1
# Get parameters for the dev model
devNonLinearParams = np.array(
[record.get(key.format(model="dev")) for key in nonlinearKeys])
devFixedParams = np.array(
[record.get(key.format(model="dev")) for key in fixedKeys])
devAmp = np.array([record.get(fluxKey.format(model="dev"))])
devAmp /= apCorr
devShapelet = ctrl.dev.getModel().makeShapeletFunction(
devNonLinearParams, devAmp, devFixedParams)
devShapelet.transformInPlace(fitSysToMeasSys.geometric)
# Get parameters for the exp model
expNonLinearParams = np.array(
[record.get(key.format(model="exp")) for key in nonlinearKeys])
expFixedParams = np.array(
[record.get(key.format(model="exp")) for key in fixedKeys])
expAmp = np.array([record.get(fluxKey.format(model="exp"))])
expAmp /= apCorr
expShapelet = ctrl.exp.getModel().makeShapeletFunction(
expNonLinearParams, expAmp, expFixedParams)
expShapelet.transformInPlace(fitSysToMeasSys.geometric)
# Get joint shapelet model
fracDev = record.get("{}_fracDev".format(baseName))
jointFlux = np.array([record.get("{}_flux".format(baseName))])
jointFlux /= apCorr
devJointShapelet = ctrl.dev.getModel()\
.makeShapeletFunction(devNonLinearParams, jointFlux*fracDev,
devFixedParams)
devJointShapelet.transformInPlace(fitSysToMeasSys.geometric)
expJointShapelet = ctrl.exp.getModel()\
.makeShapeletFunction(expNonLinearParams, jointFlux*(1-fracDev),
expFixedParams)
expJointShapelet.transformInPlace(fitSysToMeasSys.geometric)
return devShapelet, expShapelet, devJointShapelet, expJointShapelet