lsst.skymap  14.0-2-g8373656+26
discreteSkyMap.py
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1 #
2 # LSST Data Management System
3 # Copyright 2008, 2009, 2010, 2012 LSST Corporation.
4 #
5 # This product includes software developed by the
6 # LSST Project (http://www.lsst.org/).
7 #
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9 # it under the terms of the GNU General Public License as published by
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22 
23 from lsst.pex.config import ListField
24 from lsst.afw.coord import IcrsCoord
25 import lsst.afw.geom as afwGeom
26 from .cachingSkyMap import CachingSkyMap
27 from .tractInfo import ExplicitTractInfo
28 
29 __all__ = ["DiscreteSkyMap"]
30 
31 
32 class DiscreteSkyMapConfig(CachingSkyMap.ConfigClass):
33  """Configuration for the DiscreteSkyMap"""
34  raList = ListField(dtype=float, default=[], doc="Right Ascensions of tracts (ICRS, degrees)")
35  decList = ListField(dtype=float, default=[], doc="Declinations of tracts (ICRS, degrees)")
36  radiusList = ListField(dtype=float, default=[], doc="Radii of tracts (degrees)")
37 
38  def validate(self):
39  super(DiscreteSkyMapConfig, self).validate()
40  if len(self.radiusList) != len(self.raList):
41  raise ValueError("Number of radii (%d) and RAs (%d) do not match" %
42  (len(self.radiusList), len(self.raList)))
43  if len(self.radiusList) != len(self.decList):
44  raise ValueError("Number of radii (%d) and Decs (%d) do not match" %
45  (len(self.radiusList), len(self.decList)))
46 
47 
49  """Discrete sky map pixelization.
50 
51  We put a square Tract at each of the nominated coordinates.
52  """
53  ConfigClass = DiscreteSkyMapConfig
54  _version = (1, 0) # for pickle
55 
56  def __init__(self, config, version=0):
57  """Constructor
58 
59  @param[in] config: an instance of self.ConfigClass; if None the default config is used
60  @param[in] version: software version of this class, to retain compatibility with old instances
61  """
62  numTracts = len(config.radiusList)
63  super(DiscreteSkyMap, self).__init__(numTracts, config, version)
64 
65  def generateTract(self, index):
66  """Generate the TractInfo for a particular index"""
67  center = IcrsCoord(self.config.raList[index] * afwGeom.degrees,
68  self.config.decList[index] * afwGeom.degrees)
69  radius = self.config.radiusList[index]
70  wcs = self._wcsFactory.makeWcs(crPixPos=afwGeom.Point2D(0, 0), crValCoord=center)
71  return ExplicitTractInfo(index, self.config.patchInnerDimensions, self.config.patchBorder, center,
72  radius * afwGeom.degrees, self.config.tractOverlap * afwGeom.degrees, wcs)
def __init__(self, config, version=0)