def testSeparationValueGeneric(self):
"""Test if separation() returns the correct value.
"""
# This should cover arcs over the meridian, across the pole, etc.
# Do not use sphgeom as an oracle, in case SpherePoint uses it
# internally.
for lon1, lat1 in self._dataset:
point1 = SpherePoint(lon1, lat1)
x1, y1, z1 = SpherePointTestSuite.toVector(lon1, lat1)
for lon2, lat2 in self._dataset:
point2 = SpherePoint(lon2, lat2)
if lon1 != lon2 or lat1 != lat2:
# Numerically unstable at small angles, but that's ok.
x2, y2, z2 = SpherePointTestSuite.toVector(lon2, lat2)
expected = math.acos(x1 * x2 + y1 * y2 + z1 * z2)
else:
expected = 0.0
sep = point1.separation(point2)
self.assertIsInstance(sep, afwGeom.Angle)
if point1.isFinite() and point2.isFinite():
self.assertGreaterEqual(sep.asDegrees(), 0.0)
self.assertLessEqual(sep.asDegrees(), 180.0)
self.assertAlmostEqual(expected, sep.asRadians())
self.assertAnglesAlmostEqual(sep,
point2.separation(point1))
else:
self.assertTrue(math.isnan(sep.asRadians()))
self.assertTrue(
math.isnan(point2.separation(point1).asRadians()))
def testBearingToValue(self):
"""Test if bearingTo() returns the expected value.
"""
lon0 = 90.0
lat0 = 0.0 # These tests only work from the equator.
arcLen = 10.0
trials = [
# Along celestial equator
dict(lon=lon0, lat=lat0, bearing=0.0,
lonEnd=lon0+arcLen, latEnd=lat0),
# Along a meridian
dict(lon=lon0, lat=lat0, bearing=90.0,
lonEnd=lon0, latEnd=lat0+arcLen),
# 180 degree arc (should go to antipodal point)
dict(lon=lon0, lat=lat0, bearing=45.0,
lonEnd=lon0+180.0, latEnd=-lat0),
#
dict(lon=lon0, lat=lat0, bearing=45.0,
lonEnd=lon0+90.0, latEnd=lat0 + 45.0),
dict(lon=lon0, lat=lat0, bearing=225.0,
lonEnd=lon0-90.0, latEnd=lat0 - 45.0),
dict(lon=lon0, lat=np.nextafter(-90.0, inf),
bearing=90.0, lonEnd=lon0, latEnd=0.0),
dict(lon=lon0, lat=np.nextafter(-90.0, inf),
bearing=0.0, lonEnd=lon0 + 90.0, latEnd=0.0),
# Argument at a pole should work
dict(lon=lon0, lat=lat0, bearing=270.0, lonEnd=lon0, latEnd=-90.0),
# Support for non-finite values
dict(lon=lon0, lat=nan, bearing=nan, lonEnd=lon0, latEnd=45.0),
dict(lon=lon0, lat=lat0, bearing=nan, lonEnd=nan, latEnd=90.0),
dict(lon=inf, lat=lat0, bearing=nan, lonEnd=lon0, latEnd=42.0),
dict(lon=lon0, lat=lat0, bearing=nan, lonEnd=-inf, latEnd=42.0),
]
for trial in trials:
origin = SpherePoint(trial['lon']*degrees, trial['lat']*degrees)
end = SpherePoint(trial['lonEnd']*degrees, trial['latEnd']*degrees)
bearing = origin.bearingTo(end)
self.assertIsInstance(bearing, afwGeom.Angle)
if origin.isFinite() and end.isFinite():
self.assertGreaterEqual(bearing.asDegrees(), 0.0)
self.assertLess(bearing.asDegrees(), 360.0)
if origin.separation(end).asDegrees() != 180.0:
if not math.isnan(trial['bearing']):
self.assertAlmostEqual(
trial['bearing'], bearing.asDegrees(), 12)
else:
self.assertTrue(math.isnan(bearing.asRadians()))
def testEquality(self):
"""Test if tests for equality treat SpherePoints as values.
"""
# (In)equality is determined by value, not identity.
# See DM-2347, DM-2465. These asserts are testing the
# functionality of `==` and `!=` and should not be changed.
for lon1, lat1 in self._dataset:
point1 = SpherePoint(lon1, lat1)
self.assertIsInstance(point1 == point1, bool)
self.assertIsInstance(point1 != point1, bool)
if point1.isFinite():
self.assertTrue(point1 == point1)
self.assertFalse(point1 != point1)
pointCopy = copy.deepcopy(point1)
self.assertIsNot(pointCopy, point1)
self.assertEqual(pointCopy, point1)
self.assertEqual(point1, pointCopy)
self.assertFalse(pointCopy != point1)
self.assertFalse(point1 != pointCopy)
else:
self.assertFalse(point1 == point1)
self.assertTrue(point1 != point1)
for lon2, lat2 in self._dataset:
point2 = SpherePoint(lon2, lat2)
if lon1 == lon2 and lat1 == lat2 and point1.isFinite(
) and point2.isFinite():
# note: the isFinite checks are needed because if longitude is infinite
# then the resulting SpherePoint has nan as its longitude, due to wrapping
self.assertFalse(point2 != point1)
self.assertFalse(point1 != point2)
self.assertTrue(point2 == point1)
self.assertTrue(point1 == point2)
else:
self.assertTrue(point2 != point1)
self.assertTrue(point1 != point2)
self.assertFalse(point2 == point1)
self.assertFalse(point1 == point2)
# Test for transitivity (may be assumed by algorithms).
for delta in [10.0**(0.1 * x) for x in range(-150, -49, 5)]:
self.checkTransitive(delta * radians)
def testGetLatitudeValue(self):
"""Test if getLatitude() returns the expected value.
"""
for lon, lat in self._dataset:
point = SpherePoint(lon, lat)
self.assertIsInstance(point.getLatitude(), afwGeom.Angle)
# Behavior for non-finite points is undefined; depends on internal
# data representation
if point.isFinite():
self.assertGreaterEqual(point.getLatitude().asDegrees(), -90.0)
self.assertLessEqual(point.getLatitude().asDegrees(), 90.0)
self.assertAnglesAlmostEqual(lat, point.getLatitude())
def testOffsetValue(self):
"""Test if offset() returns the expected value.
"""
# This should cover arcs over the meridian, across the pole, etc.
for lon1, lat1 in self._dataset:
point1 = SpherePoint(lon1, lat1)
if point1.atPole():
continue
for lon2, lat2 in self._dataset:
if lon1 == lon2 and lat1 == lat2:
continue
point2 = SpherePoint(lon2, lat2)
bearing = point1.bearingTo(point2)
distance = point1.separation(point2)
newPoint = point1.offset(bearing, distance)
self.assertIsInstance(newPoint, SpherePoint)
if point1.isFinite() and point2.isFinite():
if not point2.atPole():
self.assertAnglesAlmostEqual(
point2.getLongitude(), newPoint.getLongitude())
self.assertAnglesAlmostEqual(
point2.getLatitude(), newPoint.getLatitude())
else:
self.assertTrue(math.isnan(
newPoint.getLongitude().asRadians()))
self.assertTrue(math.isnan(
newPoint.getLatitude().asRadians()))
# Test precision near the poles
lon = 123.0*degrees
almostPole = SpherePoint(lon, self.nextDown(90.0*degrees))
goSouth = almostPole.offset(-90.0*degrees, 90.0*degrees)
self.assertAnglesAlmostEqual(lon, goSouth.getLongitude())
self.assertAnglesAlmostEqual(0.0*degrees, goSouth.getLatitude())
goEast = almostPole.offset(0.0*degrees, 90.0*degrees)
self.assertAnglesAlmostEqual(lon + 90.0*degrees, goEast.getLongitude())
self.assertAnglesAlmostEqual(0.0*degrees, goEast.getLatitude())
def testIterResult(self):
"""Test if iteration returns the expected values.
"""
for lon, lat in self._dataset:
point = SpherePoint(lon, lat)
if point.isFinite():
# Test mechanics directly
it = iter(point)
self.assertEqual(point.getLongitude(), next(it))
self.assertEqual(point.getLatitude(), next(it))
with self.assertRaises(StopIteration):
next(it)
# Intended use case
lon, lat = point
self.assertEqual(point.getLongitude(), lon)
self.assertEqual(point.getLatitude(), lat)
def testGetLongitudeValue(self):
"""Test if getLongitude() returns the expected value.
"""
for lon, lat in self._dataset:
point = SpherePoint(lon, lat)
self.assertIsInstance(point.getLongitude(), afwGeom.Angle)
# Behavior for non-finite points is undefined; depends on internal
# data representation
if point.isFinite():
self.assertGreaterEqual(point.getLongitude().asDegrees(), 0.0)
self.assertLess(point.getLongitude().asDegrees(), 360.0)
# Longitude not guaranteed to match input at pole
if not point.atPole():
# assertAnglesAlmostEqual handles angle wrapping internally
self.assertAnglesAlmostEqual(lon, point.getLongitude())
# Vector construction should return valid longitude even in edge cases.
point = SpherePoint(afwGeom.Point3D(0.0, 0.0, -1.0))
self.assertGreaterEqual(point.getLongitude().asDegrees(), 0.0)
self.assertLess(point.getLongitude().asDegrees(), 360.0)
def testOffsetValue(self):
"""Test if offset() returns the expected value.
"""
# This should cover arcs over the meridian, across the pole, etc.
for lon1, lat1 in self._dataset:
point1 = SpherePoint(lon1, lat1)
for lon2, lat2 in self._dataset:
if lon1 == lon2 and lat1 == lat2:
continue
point2 = SpherePoint(lon2, lat2)
bearing = point1.bearingTo(point2)
distance = point1.separation(point2)
# offsetting point1 by bearing and distance should produce the same result as point2
newPoint = point1.offset(bearing, distance)
self.assertIsInstance(newPoint, SpherePoint)
self.assertSpherePointsAlmostEqual(point2, newPoint)
if newPoint.atPole():
self.assertAnglesAlmostEqual(newPoint.getLongitude(),
0 * degrees)
# measuring the separation and bearing from point1 to the new point
# should produce the requested separation and bearing
measuredDistance = point1.separation(newPoint)
self.assertAnglesAlmostEqual(measuredDistance, distance)
if abs(measuredDistance.asDegrees() - 180) > 1e-5:
# The two points are not opposite each other on the sphere,
# so the bearing has a well defined value
measuredBearing = point1.bearingTo(newPoint)
self.assertAnglesAlmostEqual(measuredBearing, bearing)
# offset by a negative amount in the opposite direction should produce the same result
newPoint2 = point1.offset(bearing + 180 * degrees, -distance)
self.assertIsInstance(newPoint2, SpherePoint)
# check angular separation (longitude is checked below)
self.assertSpherePointsAlmostEqual(newPoint, newPoint2)
if point1.isFinite() and point2.isFinite():
if not point2.atPole():
self.assertAnglesAlmostEqual(point2.getLongitude(),
newPoint.getLongitude())
self.assertAnglesAlmostEqual(point2.getLongitude(),
newPoint2.getLongitude())
self.assertAnglesAlmostEqual(point2.getLatitude(),
newPoint.getLatitude())
self.assertAnglesAlmostEqual(point2.getLatitude(),
newPoint2.getLatitude())
else:
self.assertTrue(
math.isnan(newPoint.getLongitude().asRadians()))
self.assertTrue(
math.isnan(newPoint2.getLongitude().asRadians()))
self.assertTrue(
math.isnan(newPoint.getLatitude().asRadians()))
self.assertTrue(
math.isnan(newPoint2.getLatitude().asRadians()))
# Test precision near the poles
lon = 123.0 * degrees
almostPole = SpherePoint(lon, self.nextDown(90.0 * degrees))
goSouth = almostPole.offset(-90.0 * degrees, 90.0 * degrees)
self.assertAnglesAlmostEqual(lon, goSouth.getLongitude())
self.assertAnglesAlmostEqual(0.0 * degrees, goSouth.getLatitude())
goEast = almostPole.offset(0.0 * degrees, 90.0 * degrees)
self.assertAnglesAlmostEqual(lon + 90.0 * degrees,
goEast.getLongitude())
self.assertAnglesAlmostEqual(0.0 * degrees, goEast.getLatitude())
def testDefaultConstructor(self):
sp = SpherePoint()
self.assertTrue(math.isnan(sp.getLongitude()))
self.assertTrue(math.isnan(sp.getLatitude()))
self.assertFalse(sp.isFinite())
