def testRotatedAlias(self):
"""White-box test: all representations of a pole should rotate into the same point.
"""
longitudes = [0.0, 90.0, 242.0]
latitude = 90.0
arcLen = 10.0
pole = SpherePoint(90.0 * degrees, 0.0 * degrees)
for longitude in longitudes:
point = SpherePoint(longitude * degrees, latitude * degrees)
newPoint = point.rotated(pole, arcLen * degrees)
self.assertAlmostEqual(0.0, newPoint.getLongitude().asDegrees())
self.assertAlmostEqual(80.0, newPoint.getLatitude().asDegrees())
def testRotatedValue(self):
"""Test if rotated() returns the expected value.
"""
# Try rotating about the equatorial pole (ie. along a parallel).
longitude = 90.0
latitudes = [0.0, 30.0, 60.0]
arcLen = 10.0
pole = SpherePoint(0.0 * degrees, 90.0 * degrees)
for latitude in latitudes:
point = SpherePoint(longitude * degrees, latitude * degrees)
newPoint = point.rotated(pole, arcLen * degrees)
self.assertIsInstance(newPoint, SpherePoint)
self.assertAlmostEqual(longitude + arcLen,
newPoint.getLongitude().asDegrees())
self.assertAlmostEqual(latitude,
newPoint.getLatitude().asDegrees())
# Try with pole = vernal equinox and rotate up the 90 degree meridian.
pole = SpherePoint(0.0 * degrees, 0.0 * degrees)
for latitude in latitudes:
point = SpherePoint(longitude * degrees, latitude * degrees)
newPoint = point.rotated(pole, arcLen * degrees)
self.assertAlmostEqual(longitude,
newPoint.getLongitude().asDegrees())
self.assertAlmostEqual(latitude + arcLen,
newPoint.getLatitude().asDegrees())
# Test accuracy close to coordinate pole
point = SpherePoint(90.0 * degrees, np.nextafter(90.0, -inf) * degrees)
newPoint = point.rotated(pole, 90.0 * degrees)
self.assertAlmostEqual(270.0, newPoint.getLongitude().asDegrees())
self.assertAlmostEqual(90.0 - np.nextafter(90.0, -inf),
newPoint.getLatitude().asDegrees())
# Generic pole; can't predict position, but test for rotation
# invariant.
pole = SpherePoint(283.5 * degrees, -23.6 * degrees)
for lon, lat in self._dataset:
point = SpherePoint(lon, lat)
dist = point.separation(pole)
newPoint = point.rotated(pole, -32.4 * afwGeom.radians)
self.assertNotAlmostEqual(point.getLongitude().asDegrees(),
newPoint.getLongitude().asDegrees())
self.assertNotAlmostEqual(point.getLatitude().asDegrees(),
newPoint.getLatitude().asDegrees())
self.assertAnglesAlmostEqual(dist, newPoint.separation(pole))
# Non-finite values give undefined rotations
for latitude in latitudes:
point = SpherePoint(longitude * degrees, latitude * degrees)
nanPoint = point.rotated(pole, nan * degrees)
infPoint = point.rotated(pole, inf * degrees)
self.assertTrue(math.isnan(nanPoint.getLongitude().asRadians()))
self.assertTrue(math.isnan(nanPoint.getLatitude().asRadians()))
self.assertTrue(math.isnan(infPoint.getLongitude().asRadians()))
self.assertTrue(math.isnan(infPoint.getLatitude().asRadians()))
# Non-finite points rotate into non-finite points
for point in [
SpherePoint(-inf * degrees, 1.0 * radians),
SpherePoint(32.0 * degrees, nan * radians),
]:
newPoint = point.rotated(pole, arcLen * degrees)
self.assertTrue(math.isnan(nanPoint.getLongitude().asRadians()))
self.assertTrue(math.isnan(nanPoint.getLatitude().asRadians()))
self.assertTrue(math.isnan(infPoint.getLongitude().asRadians()))
self.assertTrue(math.isnan(infPoint.getLatitude().asRadians()))
# Rotation around non-finite poles undefined
for latitude in latitudes:
point = SpherePoint(longitude * degrees, latitude * degrees)
for pole in [
SpherePoint(-inf * degrees, 1.0 * radians),
SpherePoint(32.0 * degrees, nan * radians),
]:
newPoint = point.rotated(pole, arcLen * degrees)
self.assertTrue(math.isnan(
nanPoint.getLongitude().asRadians()))
self.assertTrue(math.isnan(nanPoint.getLatitude().asRadians()))
self.assertTrue(math.isnan(
infPoint.getLongitude().asRadians()))
self.assertTrue(math.isnan(infPoint.getLatitude().asRadians()))
