lsst.coadd.chisquared  15.0-1-g788a293+26
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 from __future__ import absolute_import, division, print_function
23 
24 import lsst.coadd.utils as coaddUtils
25 from . addToCoadd import addToCoadd
26 
27 __all__ = ["Coadd"]
28 
29 
30 class Coadd(coaddUtils.Coadd):
31  """Create a chi-squared coadd.
32 
33  Parameters
34  ----------
35  bbox : `lsst.afw.geom.Box2I`
36  Bounding box of coadd Exposure with respect to parent:
37  coadd dimensions = bbox.getDimensions(); xy0 = bbox.getMin()
38  wcs : `lsst.afw.geom.SkyWcs`
39  WCS of coadd exposure
40  badMaskPlanes : `list` of `str`
41  Mask planes to pay attention to when rejecting masked pixels.
42  Specify as a collection of names.
43  badMaskPlanes should always include "EDGE".
44  logName : `str`, optional
45  Name by which messages are logged.
46  """
47 
48  def __init__(self, bbox, wcs, badMaskPlanes, logName="coadd.chisquared.Coadd"):
49  coaddUtils.Coadd.__init__(self,
50  bbox=bbox,
51  wcs=wcs,
52  badMaskPlanes=badMaskPlanes,
53  logName=logName,
54  )
55 
56  def addExposure(self, exposure, weightFactor=1.0):
57  """Add a an exposure to the coadd; it is assumed to have the same WCS as the coadd
58 
59  Parameters
60  ----------
61  exposure : `lsst.afw.image.Exposure`
62  Exposure to add to coadd; this must be:
63  - background-subtracted or background-matched to the other images 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:48
def addExposure(self, exposure, weightFactor=1.0)
Definition: coadd.py:56