LSSTApplications  10.0-2-g4f67435,11.0.rc2+1,11.0.rc2+12,11.0.rc2+3,11.0.rc2+4,11.0.rc2+5,11.0.rc2+6,11.0.rc2+7,11.0.rc2+8
LSSTDataManagementBasePackage
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 class DiscreteSkyMapConfig(CachingSkyMap.ConfigClass):
32  """Configuration for the DiscreteSkyMap"""
33  raList = ListField(dtype=float, default=[], doc="Right Ascensions of tracts (ICRS, degrees)")
34  decList = ListField(dtype=float, default=[], doc="Declinations of tracts (ICRS, degrees)")
35  radiusList = ListField(dtype=float, default=[], doc="Radii of tracts (degrees)")
36 
37  def validate(self):
38  super(DiscreteSkyMapConfig, self).validate()
39  if len(self.radiusList) != len(self.raList):
40  raise ValueError("Number of radii (%d) and RAs (%d) do not match" %
41  (len(self.radiusList), len(self.raList)))
42  if len(self.radiusList) != len(self.decList):
43  raise ValueError("Number of radii (%d) and Decs (%d) do not match" %
44  (len(self.radiusList), len(self.decList)))
45 
46 
47 class DiscreteSkyMap(CachingSkyMap):
48  """Discrete sky map pixelization.
49 
50  We put a square Tract at each of the nominated coordinates.
51  """
52  ConfigClass = DiscreteSkyMapConfig
53  _version = (1, 0) # for pickle
54 
55  def __init__(self, config, version=0):
56  """Constructor
57 
58  @param[in] config: an instance of self.ConfigClass; if None the default config is used
59  @param[in] version: software version of this class, to retain compatibility with old instances
60  """
61  numTracts = len(config.radiusList)
62  super(DiscreteSkyMap, self).__init__(numTracts, config, version)
63 
64  def generateTract(self, index):
65  """Generate the TractInfo for a particular index"""
66  center = IcrsCoord(self.config.raList[index] * afwGeom.degrees,
67  self.config.decList[index] * afwGeom.degrees)
68  radius = self.config.radiusList[index]
69  wcs = self._wcsFactory.makeWcs(crPixPos=afwGeom.Point2D(0,0), crValCoord=center)
70  return ExplicitTractInfo(index, self.config.patchInnerDimensions, self.config.patchBorder, center,
71  radius * afwGeom.degrees, self.config.tractOverlap * afwGeom.degrees, wcs)
72 
73 
A class to handle Icrs coordinates (inherits from Coord)
Definition: Coord.h:157