lsst.afw gea5801aee3+7fc0f751c0
Functions
lsst.afw.geom.utils Namespace Reference

Functions

def wcsAlmostEqualOverBBox (wcs0, wcs1, bbox, maxDiffSky=0.01 *lsst.geom.arcseconds, maxDiffPix=0.01, nx=5, ny=5)
 
def assertWcsAlmostEqualOverBBox (testCase, wcs0, wcs1, bbox, maxDiffSky=0.01 *lsst.geom.arcseconds, maxDiffPix=0.01, nx=5, ny=5, msg="WCSs differ")
 
def makeEndpoints (testCase)
 

Function Documentation

◆ assertWcsAlmostEqualOverBBox()

def lsst.afw.geom.utils.assertWcsAlmostEqualOverBBox (   testCase,
  wcs0,
  wcs1,
  bbox,
  maxDiffSky = 0.01*lsst.geom.arcseconds,
  maxDiffPix = 0.01,
  nx = 5,
  ny = 5,
  msg = "WCSs differ" 
)
Assert that two :py:class:`WCS <lsst.afw.geom.SkyWcs>` are almost equal over a grid of pixel positions

Compare pixelToSky and skyToPixel for two WCS over a rectangular grid of pixel positions.
If the WCS are too divergent at any point, call testCase.fail; the message describes
the largest error measured in pixel coordinates (if sky to pixel error was excessive)
and sky coordinates (if pixel to sky error was excessive) across the entire pixel grid.

Parameters
----------
testCase : `unittest.TestCase`
    test case the test is part of; an object supporting one method: fail(self, msgStr)
wcs0 : `lsst.afw.geom.SkyWcs`
    WCS 0
wcs1 : `lsst.afw.geom.SkyWcs`
    WCS 1
bbox : `lsst.geom.Box2I` or `lsst.geom.Box2D`
    boundaries of pixel grid over which to compare the WCSs
maxDiffSky : `lsst.geom.Angle`
    maximum separation between sky positions computed using Wcs.pixelToSky
maxDiffPix : `float`
    maximum separation between pixel positions computed using Wcs.skyToPixel
nx : `int`
    number of points in x for the grid of pixel positions
ny : `int`
    number of points in y for the grid of pixel positions
msg : `str`
    exception message prefix; details of the error are appended after ": "

Definition at line 155 of file utils.py.

◆ makeEndpoints()

def lsst.afw.geom.utils.makeEndpoints (   testCase)
Generate a representative sample of ``Endpoints``.

Parameters
----------
testCase : `unittest.TestCase`
    test case the test is part of; an object supporting one method: fail(self, msgStr)

Returns
-------
endpoints : `list`
    List of endpoints with enough diversity to exercise ``Endpoint``-related
    code. Each invocation of this method shall return independent objects.

Definition at line 200 of file utils.py.

◆ wcsAlmostEqualOverBBox()

def lsst.afw.geom.utils.wcsAlmostEqualOverBBox (   wcs0,
  wcs1,
  bbox,
  maxDiffSky = 0.01*lsst.geom.arcseconds,
  maxDiffPix = 0.01,
  nx = 5,
  ny = 5 
)
Test if two :py:class:`WCS <lsst.afw.geom.SkyWcs>` are almost equal over a grid of pixel positions.

Parameters
----------
wcs0 : `lsst.afw.geom.SkyWcs`
    WCS 0
wcs1 : `lsst.afw.geom.SkyWcs`
    WCS 1
bbox : `lsst.geom.Box2I` or `lsst.geom.Box2D`
    boundaries of pixel grid over which to compare the WCSs
maxDiffSky : `lsst.geom.Angle`
    maximum separation between sky positions computed using Wcs.pixelToSky
maxDiffPix : `float`
    maximum separation between pixel positions computed using Wcs.skyToPixel
nx : `int`
    number of points in x for the grid of pixel positions
ny : `int`
    number of points in y for the grid of pixel positions

Returns
-------
almostEqual: `bool`
    `True` if two WCS are almost equal over a grid of pixel positions, else `False`

Definition at line 116 of file utils.py.