from __future__ import absolute_import, division, print_function
#
# LSST Data Management System
# Copyright 2015 LSST Corporation.
#
# This product includes software developed by the
# LSST Project (http://www.lsst.org/).
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the LSST License Statement and
# the GNU General Public License along with this program. If not,
# see <http://www.lsstcorp.org/LegalNotices/>.
#
"""Utilities that should be imported into the lsst.afw.geom namespace when lsst.afw.geom is used
In the case of the assert functions, importing them makes them available in lsst.utils.tests.TestCase
"""
__all__ = ["wcsAlmostEqualOverBBox"]
from builtins import range
import itertools
import warnings
import math
import numpy as np
import lsst.utils.tests
from .angle import arcseconds
from .box import Box2D
from .coordinates import Point2D
from .endpoint import GenericEndpoint, Point2Endpoint, SpherePointEndpoint
def extraMsg(msg):
"""Format extra error message, if any
"""
if msg:
return ": " + msg
return ""
@lsst.utils.tests.inTestCase
def assertAnglesAlmostEqual(testCase, ang0, ang1, maxDiff=0.001*arcseconds,
ignoreWrap=True, msg="Angles differ"):
"""!Assert that two angles are almost equal, ignoring wrap differences by default
@param[in] testCase unittest.TestCase instance the test is part of;
an object supporting one method: fail(self, msgStr)
@param[in] ang0 angle 0 (an lsst.afw.geom.Angle)
@param[in] ang1 angle 1 (an lsst.afw.geom.Angle)
@param[in] maxDiff maximum difference between the two angles (an lsst.afw.geom.Angle)
@param[in] ignoreWrap ignore wrap when comparing the angles?
- if True then wrap is ignored, e.g. 0 and 360 degrees are considered equal
- if False then wrap matters, e.g. 0 and 360 degrees are considered different
@param[in] msg exception message prefix; details of the error are appended after ": "
@throw AssertionError if the difference is greater than maxDiff
"""
measDiff = ang1 - ang0
if ignoreWrap:
measDiff = measDiff.wrapCtr()
if abs(measDiff) > maxDiff:
testCase.fail("%s: measured difference %s arcsec > max allowed %s arcsec" %
(msg, measDiff.asArcseconds(), maxDiff.asArcseconds()))
@lsst.utils.tests.inTestCase
def assertPairsAlmostEqual(testCase, pair0, pair1, maxDiff=1e-7, msg="Pairs differ"):
"""!Assert that two Cartesian points are almost equal.
Each point can be any indexable pair of two floats, including
Point2D or Extent2D, a list or a tuple.
@warning Does not compare types, just compares values.
@param[in] testCase unittest.TestCase instance the test is part of;
an object supporting one method: fail(self, msgStr)
@param[in] pair0 pair 0 (a pair of floats)
@param[in] pair1 pair 1 (a pair of floats)
@param[in] maxDiff maximum radial separation between the two points
@param[in] msg exception message prefix; details of the error are appended after ": "
@throw AssertionError if the radial difference is greater than maxDiff
"""
if len(pair0) != 2:
raise RuntimeError("len(pair0)=%s != 2" % (len(pair0),))
if len(pair1) != 2:
raise RuntimeError("len(pair1)=%s != 2" % (len(pair1),))
pairDiff = [float(pair1[i] - pair0[i]) for i in range(2)]
measDiff = math.hypot(*pairDiff)
if measDiff > maxDiff:
testCase.fail("%s: measured radial distance = %s > maxDiff = %s" % (
msg, measDiff, maxDiff))
@lsst.utils.tests.inTestCase
def assertPairListsAlmostEqual(testCase, list0, list1, maxDiff=1e-7, msg=None):
"""!Assert that two lists of Cartesian points are almost equal
Each point can be any indexable pair of two floats, including
Point2D or Extent2D, a list or a tuple.
@warning Does not compare types, just values.
@param[in] testCase unittest.TestCase instance the test is part of;
an object supporting one method: fail(self, msgStr)
@param[in] list0 list of pairs 0 (each element a pair of floats)
@param[in] list1 list of pairs 1
@param[in] maxDiff maximum radial separation between the two points
@param[in] msg additional information for the error message; appended after ": "
@throw AssertionError if the radial difference is greater than maxDiff
"""
testCase.assertEqual(len(list0), len(list1))
lenList1 = np.array([len(val) for val in list0])
lenList2 = np.array([len(val) for val in list1])
testCase.assertTrue(np.all(lenList1 == 2))
testCase.assertTrue(np.all(lenList2 == 2))
diffArr = np.array([(val0[0] - val1[0], val0[1] - val1[1])
for val0, val1 in zip(list0, list1)], dtype=float)
sepArr = np.hypot(diffArr[:, 0], diffArr[:, 1])
badArr = sepArr > maxDiff
if np.any(badArr):
maxInd = np.argmax(sepArr)
testCase.fail("PairLists differ in %s places; max separation is at %s: %s > %s%s" %
(np.sum(badArr), maxInd, sepArr[maxInd], maxDiff, extraMsg(msg)))
@lsst.utils.tests.inTestCase
def assertSpherePointsAlmostEqual(testCase, sp0, sp1, maxSep=0.001*arcseconds, msg=""):
"""!Assert that two SpherePoints are almost equal
@param[in] testCase unittest.TestCase instance the test is part of;
an object supporting one method: fail(self, msgStr)
@param[in] sp0 SpherePoint 0
@param[in] sp1 SpherePoint 1
@param[in] maxSep maximum separation, an lsst.afw.geom.Angle
@param[in] msg extra information to be printed with any error message
"""
if sp0.separation(sp1) > maxSep:
testCase.fail("Angular separation between %s and %s = %s\" > maxSep = %s\"%s" %
(sp0, sp1, sp0.separation(sp1).asArcseconds(), maxSep.asArcseconds(), extraMsg(msg)))
@lsst.utils.tests.inTestCase
def assertSpherePointListsAlmostEqual(testCase, splist0, splist1, maxSep=0.001*arcseconds, msg=None):
"""!Assert that two lists of SpherePoints are almost equal
@param[in] testCase unittest.TestCase instance the test is part of;
an object supporting one method: fail(self, msgStr)
@param[in] splist0 list of SpherePoints 0
@param[in] splist1 list of SpherePoints 1
@param[in] maxSep maximum separation, an lsst.afw.geom.Angle
@param[in] msg exception message prefix; details of the error are appended after ": "
"""
testCase.assertEqual(len(splist0), len(splist1), msg=msg)
sepArr = np.array([sp0.separation(sp1)
for sp0, sp1 in zip(splist0, splist1)])
badArr = sepArr > maxSep
if np.any(badArr):
maxInd = np.argmax(sepArr)
testCase.fail("SpherePointLists differ in %s places; max separation is at %s: %s\" > %s\"%s" %
(np.sum(badArr), maxInd, sepArr[maxInd].asArcseconds(),
maxSep.asArcseconds(), extraMsg(msg)))
@lsst.utils.tests.inTestCase
def assertBoxesAlmostEqual(testCase, box0, box1, maxDiff=1e-7, msg="Boxes differ"):
"""!Assert that two boxes (Box2D or Box2I) are almost equal
@warning Does not compare types, just compares values.
@param[in] testCase unittest.TestCase instance the test is part of;
an object supporting one method: fail(self, msgStr)
@param[in] box0 box 0
@param[in] box1 box 1
@param[in] maxDiff maximum radial separation between the min points and max points
@param[in] msg exception message prefix; details of the error are appended after ": "
@throw AssertionError if the radial difference of the min points or max points is greater than maxDiff
"""
assertPairsAlmostEqual(testCase, box0.getMin(),
box1.getMin(), maxDiff=maxDiff, msg=msg + ": min")
assertPairsAlmostEqual(testCase, box0.getMax(),
box1.getMax(), maxDiff=maxDiff, msg=msg + ": max")
def _compareWcsOverBBox(wcs0, wcs1, bbox, maxDiffSky=0.01*arcseconds,
maxDiffPix=0.01, nx=5, ny=5, doShortCircuit=True):
"""!Compare two WCS over a rectangular grid of pixel positions
@param[in] wcs0 WCS 0 (an lsst.afw.geom.SkyWcs)
@param[in] wcs1 WCS 1 (an lsst.afw.geom.SkyWcs)
@param[in] bbox boundaries of pixel grid over which to compare the WCSs (an lsst.afw.geom.Box2I or Box2D)
@param[in] maxDiffSky maximum separation between sky positions computed using Wcs.pixelToSky
(an lsst.afw.geom.Angle)
@param[in] maxDiffPix maximum separation between pixel positions computed using Wcs.skyToPixel
@param[in] nx number of points in x for the grid of pixel positions
@param[in] ny number of points in y for the grid of pixel positions
@param[in] doShortCircuit if True then stop at the first error, else test all values in the grid
and return information about the worst violations found
@return return an empty string if the WCS are sufficiently close; else return a string describing
the largest error measured in pixel coordinates (if sky to pixel error was excessive) and sky coordinates
(if pixel to sky error was excessive). If doShortCircuit is true then the reported error is likely to be
much less than the maximum error across the whole pixel grid.
"""
if nx < 1 or ny < 1:
raise RuntimeError(
"nx = %s and ny = %s must both be positive" % (nx, ny))
if maxDiffSky <= 0*arcseconds:
raise RuntimeError("maxDiffSky = %s must be positive" % (maxDiffSky,))
if maxDiffPix <= 0:
raise RuntimeError("maxDiffPix = %s must be positive" % (maxDiffPix,))
bboxd = Box2D(bbox)
xList = np.linspace(bboxd.getMinX(), bboxd.getMaxX(), nx)
yList = np.linspace(bboxd.getMinY(), bboxd.getMaxY(), ny)
# we don't care about measured error unless it is too large, so initialize
# to max allowed
measDiffSky = (maxDiffSky, "?") # (sky diff, pix pos)
measDiffPix = (maxDiffPix, "?") # (pix diff, sky pos)
for x, y in itertools.product(xList, yList):
fromPixPos = Point2D(x, y)
sky0 = wcs0.pixelToSky(fromPixPos)
sky1 = wcs1.pixelToSky(fromPixPos)
diffSky = sky0.separation(sky1)
if diffSky > measDiffSky[0]:
measDiffSky = (diffSky, fromPixPos)
if doShortCircuit:
break
toPixPos0 = wcs0.skyToPixel(sky0)
toPixPos1 = wcs1.skyToPixel(sky0)
diffPix = math.hypot(*(toPixPos0 - toPixPos1))
if diffPix > measDiffPix[0]:
measDiffPix = (diffPix, sky0)
if doShortCircuit:
break
msgList = []
if measDiffSky[0] > maxDiffSky:
msgList.append("%s arcsec max measured sky error > %s arcsec max allowed sky error at pix pos=%s" %
(measDiffSky[0].asArcseconds(), maxDiffSky.asArcseconds(), measDiffSky[1]))
if measDiffPix[0] > maxDiffPix:
msgList.append("%s max measured pix error > %s max allowed pix error at sky pos=%s" %
(measDiffPix[0], maxDiffPix, measDiffPix[1]))
return "; ".join(msgList)
def wcsAlmostEqualOverBBox(wcs0, wcs1, bbox, maxDiffSky=0.01*arcseconds,
maxDiffPix=0.01, nx=5, ny=5):
"""!Return True if two WCS are almost equal over a grid of pixel positions, else False
@param[in] wcs0 WCS 0 (an lsst.afw.geom.SkyWcs)
@param[in] wcs1 WCS 1 (an lsst.afw.geom.SkyWcs)
@param[in] bbox boundaries of pixel grid over which to compare the WCSs (an lsst.afw.geom.Box2I or Box2D)
@param[in] maxDiffSky maximum separation between sky positions computed using Wcs.pixelToSky
(an lsst.afw.geom.Angle)
@param[in] maxDiffPix maximum separation between pixel positions computed using Wcs.skyToPixel
@param[in] nx number of points in x for the grid of pixel positions
@param[in] ny number of points in y for the grid of pixel positions
"""
return not bool(_compareWcsOverBBox(
wcs0 = wcs0,
wcs1 = wcs1,
bbox = bbox,
maxDiffSky = maxDiffSky,
maxDiffPix = maxDiffPix,
nx = nx,
ny = ny,
doShortCircuit = True,
))
@lsst.utils.tests.inTestCase
def assertWcsAlmostEqualOverBBox(testCase, wcs0, wcs1, bbox, maxDiffSky=0.01*arcseconds,
maxDiffPix=0.01, nx=5, ny=5, msg="WCSs differ"):
"""!Assert that two WCS 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.
@param[in] testCase unittest.TestCase instance the test is part of;
an object supporting one method: fail(self, msgStr)
@param[in] wcs0 WCS 0 (an lsst.afw.geom.SkyWcs)
@param[in] wcs1 WCS 1 (an lsst.afw.geom.SkyWcs)
@param[in] bbox boundaries of pixel grid over which to compare the WCSs (an lsst.afw.geom.Box2I or Box2D)
@param[in] maxDiffSky maximum separation between sky positions computed using Wcs.pixelToSky
(an lsst.afw.geom.Angle)
@param[in] maxDiffPix maximum separation between pixel positions computed using Wcs.skyToPixel
@param[in] nx number of points in x for the grid of pixel positions
@param[in] ny number of points in y for the grid of pixel positions
@param[in] msg exception message prefix; details of the error are appended after ": "
"""
errMsg = _compareWcsOverBBox(
wcs0 = wcs0,
wcs1 = wcs1,
bbox = bbox,
maxDiffSky = maxDiffSky,
maxDiffPix = maxDiffPix,
nx = nx,
ny = ny,
doShortCircuit = False,
)
if errMsg:
testCase.fail("%s: %s" % (msg, errMsg))
@lsst.utils.tests.inTestCase
def assertWcsNearlyEqualOverBBox(*args, **kwargs):
warnings.warn("Deprecated. Use assertWcsAlmostEqualOverBBox",
DeprecationWarning, 2)
assertWcsAlmostEqualOverBBox(*args, **kwargs)
@lsst.utils.tests.inTestCase
def makeEndpoints(testCase):
"""Generate a representative sample of Endpoints.
Returns
-------
x : `list`
List of endpoints with enough diversity to exercise Endpoint-related
code. Each invocation of this method shall return independent objects.
"""
return [GenericEndpoint(n) for n in range(1, 6)] + \
[Point2Endpoint(), SpherePointEndpoint()]
@lsst.utils.tests.inTestCase
def assertAnglesNearlyEqual(*args, **kwargs):
warnings.warn("Deprecated. Use assertAnglesAlmostEqual",
DeprecationWarning, 2)
assertAnglesAlmostEqual(*args, **kwargs)
@lsst.utils.tests.inTestCase
def assertPairsNearlyEqual(*args, **kwargs):
warnings.warn("Deprecated. Use assertPairsAlmostEqual", DeprecationWarning, 2)
assertPairsAlmostEqual(*args, **kwargs)
@lsst.utils.tests.inTestCase
def assertBoxesNearlyEqual(*args, **kwargs):
warnings.warn("Deprecated. Use assertBoxesAlmostEqual", DeprecationWarning, 2)
assertBoxesAlmostEqual(*args, **kwargs)