Coverage for python/lsst/meas/algorithms/makePsfCandidates.py: 36%
45 statements
« prev ^ index » next coverage.py v6.4.4, created at 2022-09-11 01:39 -0700
« prev ^ index » next coverage.py v6.4.4, created at 2022-09-11 01:39 -0700
1#
2# LSST Data Management System
3#
4# Copyright 2008-2017 AURA/LSST.
5#
6# This product includes software developed by the
7# LSST Project (http://www.lsst.org/).
8#
9# This program is free software: you can redistribute it and/or modify
10# it under the terms of the GNU General Public License as published by
11# the Free Software Foundation, either version 3 of the License, or
12# (at your option) any later version.
13#
14# This program is distributed in the hope that it will be useful,
15# but WITHOUT ANY WARRANTY; without even the implied warranty of
16# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17# GNU General Public License for more details.
18#
19# You should have received a copy of the LSST License Statement and
20# the GNU General Public License along with this program. If not,
21# see <https://www.lsstcorp.org/LegalNotices/>.
22#
23__all__ = ["MakePsfCandidatesConfig", "MakePsfCandidatesTask"]
25import numpy as np
27from lsst.afw.table import SourceCatalog
28import lsst.afw.math as afwMath
29import lsst.pex.config as pexConfig
30import lsst.pex.exceptions
31import lsst.pipe.base as pipeBase
32from . import makePsfCandidate
35class MakePsfCandidatesConfig(pexConfig.Config):
36 kernelSize = pexConfig.Field(
37 doc="size of the kernel to create",
38 dtype=int,
39 default=25,
40 )
41 borderWidth = pexConfig.Field(
42 doc="number of pixels to ignore around the edge of PSF candidate postage stamps",
43 dtype=int,
44 default=0,
45 )
48class MakePsfCandidatesTask(pipeBase.Task):
49 """Create PSF candidates given an input catalog.
50 """
51 ConfigClass = MakePsfCandidatesConfig
52 _DefaultName = "makePsfCandidates"
54 def __init__(self, **kwds):
55 pipeBase.Task.__init__(self, **kwds)
57 def run(self, starCat, exposure, psfCandidateField=None):
58 """Make a list of PSF candidates from a star catalog.
60 Parameters
61 ----------
62 starCat : `lsst.afw.table.SourceCatalog`
63 Catalog of stars, as returned by
64 ``lsst.meas.algorithms.starSelector.run()``.
65 exposure : `lsst.afw.image.Exposure`
66 The exposure containing the sources.
67 psfCandidateField : `str` or None
68 Name of flag field to set True for PSF candidates, or None to not
69 set a field; the field is left unchanged for non-candidates.
71 Returns
72 -------
73 struct : `lsst.pipe.base.Struct`
74 Results struct containing:
76 - ``psfCandidates`` : List of PSF candidates
77 (`list` of `lsst.meas.algorithms.PsfCandidate`).
78 - ``goodStarCat`` : Subset of ``starCat`` that was successfully made
79 into PSF candidates (`lsst.afw.table.SourceCatalog`).
81 """
82 psfResult = self.makePsfCandidates(starCat, exposure)
84 if psfCandidateField is not None:
85 isStarKey = starCat.schema[psfCandidateField].asKey()
86 for star in psfResult.goodStarCat:
87 star.set(isStarKey, True)
89 return psfResult
91 def makePsfCandidates(self, starCat, exposure):
92 """Make a list of PSF candidates from a star catalog.
94 Parameters
95 ----------
96 starCat : `lsst.afw.table.SourceCatalog`
97 Catalog of stars, as returned by
98 ``lsst.meas.algorithms.starSelector.run()``.
99 exposure : `lsst.afw.image.Exposure`
100 The exposure containing the sources.
102 Returns
103 -------
104 struct : `lsst.pipe.base.Struct`
105 Results struct containing:
107 - ``psfCandidates`` : List of PSF candidates
108 (`list` of `lsst.meas.algorithms.PsfCandidate`).
109 - ``goodStarCat`` : Subset of ``starCat`` that was successfully made
110 into PSF candidates (`lsst.afw.table.SourceCatalog`).
111 """
112 goodStarCat = SourceCatalog(starCat.schema)
114 psfCandidateList = []
115 didSetSize = False
116 for star in starCat:
117 try:
118 psfCandidate = makePsfCandidate(star, exposure)
120 # The setXXX methods are class static, but it's convenient to call them on
121 # an instance as we don't know exposures's pixel type
122 # (and hence psfCandidate's exact type)
123 if not didSetSize:
124 psfCandidate.setBorderWidth(self.config.borderWidth)
125 psfCandidate.setWidth(self.config.kernelSize + 2*self.config.borderWidth)
126 psfCandidate.setHeight(self.config.kernelSize + 2*self.config.borderWidth)
127 didSetSize = True
129 im = psfCandidate.getMaskedImage().getImage()
130 except lsst.pex.exceptions.Exception as err:
131 self.log.warning("Failed to make a psfCandidate from star %d: %s", star.getId(), err)
132 continue
134 vmax = afwMath.makeStatistics(im, afwMath.MAX).getValue()
135 if not np.isfinite(vmax):
136 continue
137 psfCandidateList.append(psfCandidate)
138 goodStarCat.append(star)
140 return pipeBase.Struct(
141 psfCandidates=psfCandidateList,
142 goodStarCat=goodStarCat,
143 )