Public Member Functions
def	__init__ (self, inputSkyWcs)

def	makeWcs (self, crvalOffset, affMatrix)

Public Attributes
	frameDict

	frameIdxs

	frameMin

	frameMax

	mapFrom

	mapTo

	lastMapBeforeSky

	origin

Detailed Description

Convenience class for appending a shifting an input SkyWcs on sky and
appending an affine transform.

The class assumes that all frames are sequential and are mapped one to the
next.

Parameters
----------
input_sky_wcs : `lsst.afw.geom.SkyWcs`
    WCS to decompose and append affine matrix and shift in on sky
    location to.

Definition at line 246 of file fitAffineWcs.py.

Constructor & Destructor Documentation

◆ init()

def lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.__init__	(	self,
		inputSkyWcs
	)

Definition at line 260 of file fitAffineWcs.py.

     def __init__(self, inputSkyWcs):
         self.frameDict = inputSkyWcs.getFrameDict()
  
         # Grab the order of the frames by index.
         # TODO: DM-20825
         #    Change the frame the transform is appended to to be explicitly
         #    the FIELD_ANGLE->IWC transform. Requires related tickets to be
         #    completed.
         domains = self.frameDict.getAllDomains()
         self.frameIdxs = np.sort([self.frameDict.getIndex(domain)
                                   for domain in domains])
         self.frameMin = np.min(self.frameIdxs)
         self.frameMax = np.max(self.frameIdxs)
  
         # Find frame just before the final mapping to sky and store those
         # indices and mappings for later.
         self.mapFrom = self.frameMax - 2
         if self.mapFrom < self.frameMin:
             self.mapFrom = self.frameMin
         self.mapTo = self.frameMax - 1
         if self.mapTo <= self.mapFrom:
             self.mapTo = self.frameMax
         self.lastMapBeforeSky = self.frameDict.getMapping(
             self.mapFrom, self.mapTo)
  
         # Get the original WCS sky location.
  
         self.origin = inputSkyWcs.getSkyOrigin()
  

Member Function Documentation

◆ makeWcs()

def lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.makeWcs	(	self,
		crvalOffset,
		affMatrix
	)

Apply a shift and affine transform to the WCS internal to this
class.

A new SkyWcs with these transforms applied is returns.

Parameters
----------
crval_shift : `numpy.ndarray`, (2,)
    Shift in radians to apply to the Wcs origin/crvals.
aff_matrix : 'numpy.ndarray', (3, 3)
    Affine matrix to apply to the mapping/transform to add to the
    WCS.

Returns
-------
outputWcs : `lsst.afw.geom.SkyWcs`
    Wcs with a final shift and affine transform applied.

Definition at line 289 of file fitAffineWcs.py.

     def makeWcs(self, crvalOffset, affMatrix):
         """Apply a shift and affine transform to the WCS internal to this
         class.
  
         A new SkyWcs with these transforms applied is returns.
  
         Parameters
         ----------
         crval_shift : `numpy.ndarray`, (2,)
             Shift in radians to apply to the Wcs origin/crvals.
         aff_matrix : 'numpy.ndarray', (3, 3)
             Affine matrix to apply to the mapping/transform to add to the
             WCS.
  
         Returns
         -------
         outputWcs : `lsst.afw.geom.SkyWcs`
             Wcs with a final shift and affine transform applied.
         """
         # Create a WCS that only maps from IWC to Sky with the shifted
         # Sky origin position. This is simply the final undistorted tangent
         # plane to sky. The PIXELS to SKY map will be become our IWC to SKY
         # map and gives us our final shift position.
         iwcsToSkyWcs = makeSkyWcs(
             Point2D(0., 0.),
             self.origin.offset(crvalOffset[0] * degrees,
                                crvalOffset[1] * arcseconds),
             np.array([[1., 0.], [0., 1.]]))
         iwcToSkyMap = iwcsToSkyWcs.getFrameDict().getMapping("PIXELS", "SKY")
  
         # Append a simple affine Matrix transform to the current to the
         # second to last frame mapping. e.g. the one just before IWC to SKY.
         newMapping = self.lastMapBeforeSky.then(astshim.MatrixMap(affMatrix))
  
         # Create a new frame dict starting from the input_sky_wcs's first
         # frame. Append the correct mapping created above and our new on
         # sky location.
         outputFrameDict = astshim.FrameDict(
             self.frameDict.getFrame(self.frameMin))
         for frameIdx in self.frameIdxs:
             if frameIdx == self.mapFrom:
                 outputFrameDict.addFrame(
                     self.mapFrom,
                     newMapping,
                     self.frameDict.getFrame(self.mapTo))
             elif frameIdx >= self.mapTo:
                 continue
             else:
                 outputFrameDict.addFrame(
                     frameIdx,
                     self.frameDict.getMapping(frameIdx, frameIdx + 1),
                     self.frameDict.getFrame(frameIdx + 1))
         # Append the final sky frame to the frame dict.
         outputFrameDict.addFrame(
             self.frameMax - 1,
             iwcToSkyMap,
             iwcsToSkyWcs.getFrameDict().getFrame("SKY"))
  
         return SkyWcs(outputFrameDict)

Member Data Documentation

◆ frameDict

lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.frameDict

Definition at line 261 of file fitAffineWcs.py.

◆ frameIdxs

lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.frameIdxs

Definition at line 269 of file fitAffineWcs.py.

◆ frameMax

lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.frameMax

Definition at line 272 of file fitAffineWcs.py.

◆ frameMin

lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.frameMin

Definition at line 271 of file fitAffineWcs.py.

◆ lastMapBeforeSky

lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.lastMapBeforeSky

Definition at line 282 of file fitAffineWcs.py.

◆ mapFrom

lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.mapFrom

Definition at line 276 of file fitAffineWcs.py.

◆ mapTo

lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.mapTo

Definition at line 279 of file fitAffineWcs.py.

◆ origin

lsst.meas.astrom.fitAffineWcs.TransformedSkyWcsMaker.origin

Definition at line 287 of file fitAffineWcs.py.

The documentation for this class was generated from the following file:

/j/snowflake/release/lsstsw/stack/lsst-scipipe-0.7.0/Linux64/meas_astrom/22.0.1-12-g44dc1dc+2a20fdde0d/python/lsst/meas/astrom/fitAffineWcs.py

Public Member Functions

Public Attributes