lsst.skymap  16.0-5-gef99c9f
wcsFactory.py
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1 #
2 # LSST Data Management System
3 # Copyright 2008, 2009, 2010 LSST Corporation.
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5 # This product includes software developed by the
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22 import lsst.afw.geom as afwGeom
23 
24 
25 class WcsFactory:
26  """A factory for creating Wcs objects for the sky tiles.
27  """
28 
29  def __init__(self, pixelScale, projection, rotation=0*afwGeom.radians, flipX=False):
30  """Make a WcsFactory
31 
32  @param[in] pixelScale: desired scale, as sky/pixel, an afwGeom.Angle
33  @param[in] projection: FITS-standard 3-letter name of projection, e.g.:
34  TAN (tangent), STG (stereographic), MOL (Mollweide's), AIT (Hammer-Aitoff)
35  see Representations of celestial coordinates in FITS (Calabretta and Greisen, 2002)
36  @param[in] rotation: Rotation relative to cardinal, as an lsst.afw.geom.Angle
37  @param[in] flipX: Flip the X axis?
38  """
39  if len(projection) != 3:
40  raise RuntimeError("projection=%r; must have length 3" % (projection,))
41  self._projection = projection
42  self._cdMatrix = afwGeom.makeCdMatrix(scale=pixelScale, orientation=rotation, flipX=flipX)
43 
44  def makeWcs(self, crPixPos, crValCoord):
45  """Make a Wcs
46 
47  @param[in] crPixPos: crPix for WCS, using the LSST standard; an afwGeom.Point2D or pair of floats
48  @param[in] crValCoord: ICRS crVal for WCS (lsst.afw.geom.SpherePoint)
49  """
50  return afwGeom.makeSkyWcs(crpix=crPixPos, crval=crValCoord,
51  cdMatrix=self._cdMatrix, projection=self._projection)
def makeWcs(self, crPixPos, crValCoord)
Definition: wcsFactory.py:44
def __init__(self, pixelScale, projection, rotation=0 *afwGeom.radians, flipX=False)
Definition: wcsFactory.py:29