lsst.coadd.chisquared  16.0-2-g839ba83+40
coadd.py
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1 #
2 # LSST Data Management System
3 # Copyright 2008, 2009, 2010 LSST Corporation.
4 #
5 # This product includes software developed by the
6 # LSST Project (http://www.lsst.org/).
7 #
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21 #
22 import lsst.coadd.utils as coaddUtils
23 from . addToCoadd import addToCoadd
24 
25 __all__ = ["Coadd"]
26 
27 
28 class Coadd(coaddUtils.Coadd):
29  """Create a chi-squared coadd.
30 
31  Parameters
32  ----------
33  bbox : `lsst.afw.geom.Box2I`
34  Bounding box of coadd Exposure with respect to parent:
35  coadd dimensions = bbox.getDimensions(); xy0 = bbox.getMin()
36  wcs : `lsst.afw.geom.SkyWcs`
37  WCS of coadd exposure
38  badMaskPlanes : `list` of `str`
39  Mask planes to pay attention to when rejecting masked pixels.
40  Specify as a collection of names.
41  badMaskPlanes should always include "EDGE".
42  logName : `str`, optional
43  Name by which messages are logged.
44  """
45 
46  def __init__(self, bbox, wcs, badMaskPlanes, logName="coadd.chisquared.Coadd"):
47  coaddUtils.Coadd.__init__(self,
48  bbox=bbox,
49  wcs=wcs,
50  badMaskPlanes=badMaskPlanes,
51  logName=logName,
52  )
53 
54  def addExposure(self, exposure, weightFactor=1.0):
55  """Add a an exposure to the coadd; it is assumed to have the same WCS
56  as the coadd
57 
58  Parameters
59  ----------
60  exposure : `lsst.afw.image.Exposure`
61  Exposure to add to coadd; this must be:
62  - background-subtracted or background-matched to the other images
63  being coadded
64  - psf-matched to the desired PSF model (optional)
65  - warped to match the coadd
66  weightFactor : `float`
67  weight with which to add exposure to coadd
68 
69  Returns
70  -------
71  overlapBBox : `lsst.afw.geom.Box2I`
72  Region of overlap between ``exposure`` and coadd in parent
73  coordinates.
74  weight : `float`
75  Weight with which ``exposure`` was added to coadd;
76  weight = weightFactor for this kind of coadd.
77  """
78  self._log.info("add exposure to coadd")
79 
80  # save filter info
81  filter = exposure.getFilter()
82  self._filterDict.setdefault(filter.getName(), filter)
83 
84  overlapBBox = addToCoadd(self._coadd.getMaskedImage(), self._weightMap,
85  exposure.getMaskedImage(), self._badPixelMask, weightFactor)
86 
87  return overlapBBox, weightFactor
def __init__(self, bbox, wcs, badMaskPlanes, logName="coadd.chisquared.Coadd")
Definition: coadd.py:46
def addExposure(self, exposure, weightFactor=1.0)
Definition: coadd.py:54