def testRaDecFromPupil(self):
"""
Test conversion from pupil coordinates back to Ra, Dec
"""
mjd = ModifiedJulianDate(TAI=52000.0)
solarRA, solarDec = solarRaDec(mjd)
# to make sure that we are more than 45 degrees from the Sun as required
# for _icrsFromObserved to be at all accurate
raCenter = solarRA + 100.0
decCenter = solarDec - 30.0
obs = ObservationMetaData(pointingRA=raCenter,
pointingDec=decCenter,
boundType='circle',
boundLength=0.1,
rotSkyPos=23.0,
mjd=mjd)
nSamples = 1000
rng = np.random.RandomState(42)
ra = (rng.random_sample(nSamples) * 0.1 - 0.2) + np.radians(raCenter)
dec = (rng.random_sample(nSamples) * 0.1 - 0.2) + np.radians(decCenter)
xp, yp = _pupilCoordsFromRaDec(ra, dec, obs_metadata=obs, epoch=2000.0)
raTest, decTest = _raDecFromPupilCoords(xp,
yp,
obs_metadata=obs,
epoch=2000.0)
distance = arcsecFromRadians(haversine(ra, dec, raTest, decTest))
dex = np.argmax(distance)
worstSolarDistance = distanceToSun(np.degrees(ra[dex]),
np.degrees(dec[dex]), mjd)
msg = "_raDecFromPupilCoords off by %e arcsec at distance to Sun of %e degrees" % \
(distance.max(), worstSolarDistance)
self.assertLess(distance.max(), 1.0e-6, msg=msg)
# now check that passing in the xp, yp values one at a time still gives
# the right answer
for ix in range(len(ra)):
ra_f, dec_f = _raDecFromPupilCoords(xp[ix],
yp[ix],
obs_metadata=obs,
epoch=2000.0)
self.assertIsInstance(ra_f, np.float)
self.assertIsInstance(dec_f, np.float)
dist_f = arcsecFromRadians(
haversine(ra_f, dec_f, raTest[ix], decTest[ix]))
self.assertLess(dist_f, 1.0e-9)
def testRaDecFromPupil_noRefraction(self):
"""
Test conversion from pupil coordinates back to Ra, Dec
with includeRefraction=False
"""
mjd = ModifiedJulianDate(TAI=52000.0)
solarRA, solarDec = solarRaDec(mjd)
# to make sure that we are more than 45 degrees from the Sun as required
# for _icrsFromObserved to be at all accurate
raCenter = solarRA + 100.0
decCenter = solarDec - 30.0
obs = ObservationMetaData(pointingRA=raCenter,
pointingDec=decCenter,
boundType='circle',
boundLength=0.1,
rotSkyPos=23.0,
mjd=mjd)
nSamples = 1000
rng = np.random.RandomState(42)
ra = (rng.random_sample(nSamples) * 0.1 - 0.2) + np.radians(raCenter)
dec = (rng.random_sample(nSamples) * 0.1 - 0.2) + np.radians(decCenter)
xp, yp = _pupilCoordsFromRaDec(ra, dec, obs_metadata=obs, epoch=2000.0,
includeRefraction=False)
raTest, decTest = _raDecFromPupilCoords(
xp, yp, obs_metadata=obs, epoch=2000.0,
includeRefraction=False)
distance = arcsecFromRadians(haversine(ra, dec, raTest, decTest))
dex = np.argmax(distance)
worstSolarDistance = distanceToSun(
np.degrees(ra[dex]), np.degrees(dec[dex]), mjd)
msg = "_raDecFromPupilCoords off by %e arcsec at distance to Sun of %e degrees" % \
(distance.max(), worstSolarDistance)
self.assertLess(distance.max(), 1.0e-6, msg=msg)
# now check that passing in the xp, yp values one at a time still gives
# the right answer
for ix in range(len(ra)):
ra_f, dec_f = _raDecFromPupilCoords(xp[ix], yp[ix], obs_metadata=obs, epoch=2000.0,
includeRefraction=False)
self.assertIsInstance(ra_f, np.float)
self.assertIsInstance(dec_f, np.float)
dist_f = arcsecFromRadians(haversine(ra_f, dec_f, raTest[ix], decTest[ix]))
self.assertLess(dist_f, 1.0e-9)
def testRaDecFromPupil(self):
"""
Test conversion from pupil coordinates back to Ra, Dec
"""
mjd = ModifiedJulianDate(TAI=52000.0)
solarRA, solarDec = solarRaDec(mjd.TDB)
# to make sure that we are more than 45 degrees from the Sun as required
# for _icrsFromObserved to be at all accurate
raCenter = solarRA + 100.0
decCenter = solarDec - 30.0
obs = ObservationMetaData(pointingRA=raCenter,
pointingDec=decCenter,
boundType='circle',
boundLength=0.1,
rotSkyPos=23.0,
mjd=mjd)
nSamples = 1000
numpy.random.seed(42)
ra = (numpy.random.random_sample(nSamples)*0.1-0.2) + numpy.radians(raCenter)
dec = (numpy.random.random_sample(nSamples)*0.1-0.2) + numpy.radians(decCenter)
xp, yp = _pupilCoordsFromRaDec(ra, dec, obs_metadata=obs, epoch=2000.0)
raTest, decTest = _raDecFromPupilCoords(xp, yp, obs_metadata=obs, epoch=2000.0)
distance = arcsecFromRadians(haversine(ra, dec, raTest, decTest))
dex = numpy.argmax(distance)
worstSolarDistance = distanceToSun(numpy.degrees(ra[dex]), numpy.degrees(dec[dex]), mjd.TDB)
msg = "_raDecFromPupilCoords off by %e arcsec at distance to Sun of %e degrees" % \
(distance.max(), worstSolarDistance)
self.assertLess(distance.max(), 0.005, msg=msg)
def testraDecFromPupilCoords(self):
obs = ObservationMetaData(pointingRA=23.5, pointingDec=-115.0, mjd=42351.0, rotSkyPos=127.0)
xpList = np.random.random_sample(100)*0.25*np.pi
ypList = np.random.random_sample(100)*0.25*np.pi
raRad, decRad = utils._raDecFromPupilCoords(xpList, ypList, obs_metadata=obs, epoch=2000.0)
raDeg, decDeg = utils.raDecFromPupilCoords(xpList, ypList, obs_metadata=obs, epoch=2000.0)
dRa = utils.arcsecFromRadians(raRad-np.radians(raDeg))
np.testing.assert_array_almost_equal(dRa, np.zeros(len(xpList)), 9)
dDec = utils.arcsecFromRadians(decRad-np.radians(decDeg))
np.testing.assert_array_almost_equal(dDec, np.zeros(len(xpList)), 9)
def testraDecFromPupilCoords(self):
obs = ObservationMetaData(pointingRA=23.5,
pointingDec=-115.0,
mjd=42351.0,
rotSkyPos=127.0)
xpList = self.rng.random_sample(100) * 0.25 * np.pi
ypList = self.rng.random_sample(100) * 0.25 * np.pi
raRad, decRad = utils._raDecFromPupilCoords(xpList,
ypList,
obs_metadata=obs,
epoch=2000.0)
raDeg, decDeg = utils.raDecFromPupilCoords(xpList,
ypList,
obs_metadata=obs,
epoch=2000.0)
dRa = utils.arcsecFromRadians(raRad - np.radians(raDeg))
np.testing.assert_array_almost_equal(dRa, np.zeros(len(xpList)), 9)
dDec = utils.arcsecFromRadians(decRad - np.radians(decDeg))
np.testing.assert_array_almost_equal(dDec, np.zeros(len(xpList)), 9)
def _raDecFromPixelCoordsLSST(xPix,
yPix,
chipName,
band='r',
obs_metadata=None,
epoch=2000.0,
includeDistortion=True):
"""
Convert pixel coordinates into RA, Dec
@param [in] xPix is the x pixel coordinate. It can be either
a float or a numpy array.
@param [in] yPix is the y pixel coordinate. It can be either
a float or a numpy array.
@param [in] chipName is the name of the chip(s) on which the pixel coordinates
are defined. This can be a list (in which case there should be one chip name
for each (xPix, yPix) coordinate pair), or a single value (in which case, all
of the (xPix, yPix) points will be reckoned on that chip).
@param [in] band is the filter we are simulating (default=r)
@param [in] obs_metadata is an ObservationMetaData defining the pointing
@param [in] epoch is the mean epoch in years of the celestial coordinate system.
Default is 2000.
@param [in] includeDistortion is a boolean. If True (default), then this method will
expect the true pixel coordinates with optical distortion included. If False, this
method will expect TAN_PIXEL coordinates, which are the pixel coordinates with
estimated optical distortion removed. See the documentation in afw.cameraGeom for more
details.
@param [out] a 2-D numpy array in which the first row is the RA coordinate
and the second row is the Dec coordinate (both in radians; in the International
Celestial Reference System)
WARNING: This method does not account for apparent motion due to parallax.
This method is only useful for mapping positions on a theoretical focal plane
to positions on the celestial sphere.
"""
are_arrays, \
chipNameList = _validate_inputs_and_chipname([xPix, yPix],
['xPix', 'yPix'],
'raDecFromPixelCoords',
chipName,
chipname_can_be_none=False)
if epoch is None:
raise RuntimeError(
"You cannot call raDecFromPixelCoords without specifying an epoch")
if obs_metadata is None:
raise RuntimeError(
"You cannot call raDecFromPixelCoords without an ObservationMetaData"
)
if obs_metadata.mjd is None:
raise RuntimeError(
"The ObservationMetaData in raDecFromPixelCoords must have an mjd")
if obs_metadata.rotSkyPos is None:
raise RuntimeError(
"The ObservationMetaData in raDecFromPixelCoords must have a rotSkyPos"
)
xPupilList, yPupilList = pupilCoordsFromPixelCoordsLSST(
xPix,
yPix,
chipNameList,
band=band,
includeDistortion=includeDistortion)
raOut, decOut = _raDecFromPupilCoords(xPupilList,
yPupilList,
obs_metadata=obs_metadata,
epoch=epoch)
return np.array([raOut, decOut])
def _raDecFromPixelCoords(xPix, yPix, chipName, camera=None,
obs_metadata=None, epoch=2000.0, includeDistortion=True):
"""
Convert pixel coordinates into RA, Dec
@param [in] xPix is the x pixel coordinate. It can be either
a float or a numpy array.
@param [in] yPix is the y pixel coordinate. It can be either
a float or a numpy array.
@param [in] chipName is the name of the chip(s) on which the pixel coordinates
are defined. This can be a list (in which case there should be one chip name
for each (xPix, yPix) coordinate pair), or a single value (in which case, all
of the (xPix, yPix) points will be reckoned on that chip).
@param [in] camera is an afw.CameraGeom.camera object defining the camera
@param [in] obs_metadata is an ObservationMetaData defining the pointing
@param [in] epoch is the mean epoch in years of the celestial coordinate system.
Default is 2000.
@param [in] includeDistortion is a boolean. If True (default), then this method will
expect the true pixel coordinates with optical distortion included. If False, this
method will expect TAN_PIXEL coordinates, which are the pixel coordinates with
estimated optical distortion removed. See the documentation in afw.cameraGeom for more
details.
@param [out] a 2-D numpy array in which the first row is the RA coordinate
and the second row is the Dec coordinate (both in radians; in the International
Celestial Reference System)
WARNING: This method does not account for apparent motion due to parallax.
This method is only useful for mapping positions on a theoretical focal plane
to positions on the celestial sphere.
"""
are_arrays, \
chipNameList = _validate_inputs_and_chipname([xPix, yPix],
['xPix', 'yPix'],
'raDecFromPixelCoords',
chipName,
chipname_can_be_none=False)
if camera is None:
raise RuntimeError("You cannot call raDecFromPixelCoords without specifying a camera")
if epoch is None:
raise RuntimeError("You cannot call raDecFromPixelCoords without specifying an epoch")
if obs_metadata is None:
raise RuntimeError("You cannot call raDecFromPixelCoords without an ObservationMetaData")
if obs_metadata.mjd is None:
raise RuntimeError("The ObservationMetaData in raDecFromPixelCoords must have an mjd")
if obs_metadata.rotSkyPos is None:
raise RuntimeError("The ObservationMetaData in raDecFromPixelCoords must have a rotSkyPos")
xPupilList, yPupilList = pupilCoordsFromPixelCoords(xPix, yPix, chipNameList,
camera=camera, includeDistortion=includeDistortion)
raOut, decOut = _raDecFromPupilCoords(xPupilList, yPupilList,
obs_metadata=obs_metadata, epoch=epoch)
return np.array([raOut, decOut])
def _raDecFromPixelCoords(xPixList, yPixList, chipNameList, camera=None,
obs_metadata=None, epoch=None, includeDistortion=True):
"""
Convert pixel coordinates into RA, Dec
@param [in] xPixList is a numpy array of x pixel coordinates
@param [in] yPixList is a numpy array of y pixel coordinates
@param [in] chipNameList is a numpy array of chip names (corresponding to the points
in xPixList and yPixList)
@param [in] camera is an afw.CameraGeom.camera object defining the camera
@param [in] obs_metadata is an ObservationMetaData defining the pointing
@param [in] epoch is the mean epoch in years of the celestial coordinate system
@param [in] includeDistortion is a boolean. If True (default), then this method will
expect the true pixel coordinates with optical distortion included. If False, this
method will expect TAN_PIXEL coordinates, which are the pixel coordinates with
estimated optical distortion removed. See the documentation in afw.cameraGeom for more
details.
@param [out] a 2-D numpy array in which the first row is the RA coordinate
and the second row is the Dec coordinate (both in radians; in the International
Celestial Reference System)
"""
if camera is None:
raise RuntimeError("You cannot call raDecFromPixelCoords without specifying a camera")
if epoch is None:
raise RuntimeError("You cannot call raDecFromPixelCoords without specifying an epoch")
if obs_metadata is None:
raise RuntimeError("You cannot call raDecFromPixelCoords without an ObservationMetaData")
if obs_metadata.mjd is None:
raise RuntimeError("The ObservationMetaData in raDecFromPixelCoords must have an mjd")
if obs_metadata.rotSkyPos is None:
raise RuntimeError("The ObservationMetaData in raDecFromPixelCoords must have a rotSkyPos")
if not isinstance(xPixList, numpy.ndarray) or not isinstance(yPixList, numpy.ndarray):
raise RuntimeError("You must pass numpy arrays of xPix and yPix to raDecFromPixelCoords")
if len(xPixList)!=len(yPixList):
raise RuntimeError("You passed %d xPix coordinates but %d yPix coordinates " \
% (len(xPixList), len(yPixList)) \
+"to raDecFromPixelCoords")
if len(xPixList)!=len(chipNameList):
raise RuntimeError("You passed %d pixel coordinate pairs but %d chip names " \
% (len(xPixList), len(chipNameList)) \
+"to raDecFromPixelCoords")
xPupilList, yPupilList = pupilCoordsFromPixelCoords(xPixList, yPixList, chipNameList,
camera=camera, includeDistortion=includeDistortion)
raOut, decOut = _raDecFromPupilCoords(xPupilList, yPupilList,
obs_metadata=obs_metadata, epoch=epoch)
return numpy.array([raOut, decOut])