def test_against_jpl_horizons():
"""Check that Astropy gives consistent results with the JPL Horizons example.
The input parameters and reference results are taken from this page:
(from the first row of the Results table at the bottom of that page)
http://ssd.jpl.nasa.gov/?horizons_tutorial
"""
print('NASA JPL')
obstime = Time('1998-07-28 03:00')
location = EarthLocation(lon=Angle('248.405300d'),
lat=Angle('31.9585d'),
height=2.06 * u.km)
# No atmosphere
altaz_frame = AltAz(obstime=obstime, location=location)
altaz = SkyCoord('143.2970d 2.6223d', frame=altaz_frame)
radec_actual = altaz.transform_to('icrs')
print('Astropy: ', radec_actual)
radec_expected = SkyCoord('19h24m55.01s -40d56m28.9s', frame='icrs')
print('Source: ', radec_expected)
distance = radec_actual.separation(radec_expected).to('arcsec')
#assert distance < 1 * u.arcsec
# SAPPHiRE
longitude = 248.405300
latitude = 31.9585
utc = datetime.datetime(1998, 7, 28, 3, 0)
elevation = np.radians(2.6223)
azi = np.radians(143.2970)
gps = clock.utc_to_gps(calendar.timegm(utc.utctimetuple()))
zenith, azimuth = celestial.horizontal_to_zenithazimuth(elevation, azi)
ra, dec = celestial.zenithazimuth_to_equatorial(longitude, latitude, gps,
zenith, azimuth)
print('SAPPHiRE: ra=%f, dec=%f' % (np.degrees(ra), np.degrees(dec)))
def test_against_jpl_horizons(self):
"""Check for consistent results with the JPL Horizons example.
The input parameters and reference results are taken from this page:
(from the first row of the Results table at the bottom of that page)
http://ssd.jpl.nasa.gov/?horizons_tutorial
"""
# NASA JPL
ra_expected = np.radians(291.229208333)
dec_expected = np.radians(-40.9413611111)
# Astropy 1.0rc1
ra_astropy = np.radians(291.229161499)
dec_astropy = np.radians(-40.9413052259)
# Data
# Kitt Peak
longitude = 248.405300
latitude = 31.9585
utc = datetime.datetime(1998, 7, 28, 3, 0)
altitude = np.radians(2.6223)
azi = np.radians(143.2970)
# SAPPHiRE
gps = clock.utc_to_gps(calendar.timegm(utc.utctimetuple()))
zenith, azimuth = celestial.horizontal_to_zenithazimuth(altitude, azi)
ra, dec = celestial.zenithazimuth_to_equatorial(
longitude, latitude, gps, zenith, azimuth)
self.assertAlmostEqual(ra, ra_expected, 3)
self.assertAlmostEqual(ra, ra_astropy, 3)
self.assertAlmostEqual(dec, dec_expected, 2)
self.assertAlmostEqual(dec, dec_astropy, 2)
def test_against_pyephem(self):
"""Check for consistent results with one PyEphem example.
PyEphem: http://rhodesmill.org/pyephem/
See example input and output here:
https://gist.github.com/zonca/1672906
https://github.com/phn/pytpm/issues/2#issuecomment-3698679
"""
# PyEphem
ra_expected = np.radians(196.497518)
dec_expected = np.radians(-4.569323)
# Astropy 1.0rc1
ra_astropy = np.radians(196.49537283)
dec_astropy = np.radians(-4.5606942763)
# Data
longitude = base.sexagesimal_to_decimal(-109, -24, -53.1)
latitude = base.sexagesimal_to_decimal(33, 41, 46.0)
utc = datetime.datetime(2011, 9, 18, 8, 50)
altitude = np.radians(-60.7665)
azi = np.radians(6.8927)
# SAPPHiRE
gps = clock.utc_to_gps(calendar.timegm(utc.utctimetuple()))
zenith, azimuth = celestial.horizontal_to_zenithazimuth(altitude, azi)
ra, dec = celestial.zenithazimuth_to_equatorial(
longitude, latitude, gps, zenith, azimuth)
self.assertAlmostEqual(ra, ra_expected, 2)
self.assertAlmostEqual(ra, ra_astropy, 2)
self.assertAlmostEqual(dec, dec_expected, 2)
self.assertAlmostEqual(dec, dec_astropy, 2)
def test_against_pyephem(self):
"""Check for consistent results with one PyEphem example.
PyEphem: http://rhodesmill.org/pyephem/
See example input and output here:
https://gist.github.com/zonca/1672906
https://github.com/phn/pytpm/issues/2#issuecomment-3698679
"""
# PyEphem
ra_expected = np.radians(196.497518)
dec_expected = np.radians(-4.569323)
# Astropy 1.0rc1
ra_astropy = np.radians(196.49537283)
dec_astropy = np.radians(-4.5606942763)
# Data
longitude = base.sexagesimal_to_decimal(-109, -24, -53.1)
latitude = base.sexagesimal_to_decimal(33, 41, 46.0)
utc = datetime.datetime(2011, 9, 18, 8, 50)
altitude = np.radians(-60.7665)
azi = np.radians(6.8927)
# SAPPHiRE
gps = clock.utc_to_gps(calendar.timegm(utc.utctimetuple()))
zenith, azimuth = celestial.horizontal_to_zenithazimuth(altitude, azi)
ra, dec = celestial.zenithazimuth_to_equatorial(latitude, longitude,
gps, zenith, azimuth)
self.assertAlmostEqual(ra, ra_expected, 2)
self.assertAlmostEqual(ra, ra_astropy, 2)
self.assertAlmostEqual(dec, dec_expected, 2)
self.assertAlmostEqual(dec, dec_astropy, 2)
def test_against_jpl_horizons(self):
"""Check for consistent results with the JPL Horizons example.
The input parameters and reference results are taken from this page:
(from the first row of the Results table at the bottom of that page)
http://ssd.jpl.nasa.gov/?horizons_tutorial
"""
# NASA JPL
ra_expected = np.radians(291.229208333)
dec_expected = np.radians(-40.9413611111)
# Astropy 1.0rc1
ra_astropy = np.radians(291.229161499)
dec_astropy = np.radians(-40.9413052259)
# Data
# Kitt Peak
longitude = 248.405300
latitude = 31.9585
utc = datetime.datetime(1998, 7, 28, 3, 0)
altitude = np.radians(2.6223)
azi = np.radians(143.2970)
# SAPPHiRE
gps = clock.utc_to_gps(calendar.timegm(utc.utctimetuple()))
zenith, azimuth = celestial.horizontal_to_zenithazimuth(altitude, azi)
ra, dec = celestial.zenithazimuth_to_equatorial(latitude, longitude,
gps, zenith, azimuth)
self.assertAlmostEqual(ra, ra_expected, 3)
self.assertAlmostEqual(ra, ra_astropy, 3)
self.assertAlmostEqual(dec, dec_expected, 2)
self.assertAlmostEqual(dec, dec_astropy, 2)
def test_against_hor2eq():
"""Check that Astropy gives consistent results with an IDL hor2eq example.
See EXAMPLE input and output here:
http://idlastro.gsfc.nasa.gov/ftp/pro/astro/hor2eq.pro
"""
print('IDL hor2eq')
# Observatory position for `kpno` from here:
# http://idlastro.gsfc.nasa.gov/ftp/pro/astro/observatory.pro
location = EarthLocation(lon=Angle('-111d36.0m'),
lat=Angle('31d57.8m'),
height=2120. * u.m)
# obstime = Time('2041-12-26 05:00:00')
obstime = Time(2466879.7083333, format='jd')
# obstime += TimeDelta(-2, format='sec')
altaz_frame = AltAz(obstime=obstime, location=location)
altaz = SkyCoord('264d55m06s 37d54m41s', frame=altaz_frame)
radec_frame = 'icrs'
# The following transformation throws a warning about precision problems
# because the observation date is in the future
with catch_warnings() as _:
radec_actual = altaz.transform_to(radec_frame)
print('Astropy: ', radec_actual)
radec_expected = SkyCoord('00h13m14.1s +15d11m0.3s', frame=radec_frame)
print('Source: ', radec_expected)
distance = radec_actual.separation(radec_expected).to('arcsec')
# print(distance)
# TODO: why is there a difference of 2.6 arcsec currently?
# radec_expected = ra=3.30875 deg, dec=15.183416666666666 deg
# radec_actual = ra=3.3094193224314625 deg, dec=15.183757021354532 deg
# distance = 2.6285 arcsec
# assert distance < 5 * u.arcsec
# SAPPHiRE
longitude = -111.6
latitude = 31.9633
jd = 2466879.7083333
elevation = (37, 54, 41)
azi = (264, 55, 6)
# lst = clock.gmst_to_lst(clock.juliandate_to_gmst(jd), longitude)
# Matches LAST = +03 53 53.6 in the hor2eq.pro
gps = clock.utc_to_gps(
calendar.timegm(clock.juliandate_to_utc(jd).utctimetuple()))
zenith, azimuth = celestial.horizontal_to_zenithazimuth(
np.radians(base.sexagesimal_to_decimal(*elevation)),
np.radians(base.sexagesimal_to_decimal(*azi)))
ra, dec = celestial.zenithazimuth_to_equatorial(longitude, latitude, gps,
zenith, azimuth)
print('SAPPHiRE: ra=%f, dec=%f' % (np.degrees(ra), np.degrees(dec)))
def calc_sapphire():
"""Calculate coordinates using SAPPHiRE
"""
ra, dec = celestial.zenithazimuth_to_equatorial(LONGITUDE, LATITUDE, GPS,
ZENITH, AZIMUTH)
sra = base.decimal_to_sexagesimal(angles.radians_to_hours(ra))
sdec = base.decimal_to_sexagesimal(np.degrees(dec))
print 'SAPPHiRE: %10.6f %10.6f' % (np.degrees(ra), np.degrees(dec))
def test_against_hor2eq(self):
"""Check for consistent results with an IDL hor2eq example.
See EXAMPLE input and output here:
http://idlastro.gsfc.nasa.gov/ftp/pro/astro/hor2eq.pro
Observatory position for ``kpno`` from here:
http://idlastro.gsfc.nasa.gov/ftp/pro/astro/observatory.pro
"""
# IDL hor2eq
ra_expected = np.radians(3.30875)
dec_expected = np.radians(15.183416666666666)
# Astropy 1.0rc1
ra_astropy = np.radians(3.3094193224314625)
dec_astropy = np.radians(15.183757021354532)
# KPNO observatory
longitude = -111.6
latitude = 31.9633
# Observation time
jd = 2466879.7083333
# Altitude Azimuth
altitude = (37, 54, 41)
azi = (264, 55, 6)
# lst = clock.gmst_to_lst(clock.juliandate_to_gmst(jd), longitude)
# Matches LAST = +03 53 53.6 in the hor2eq.pro
# SAPPHiRE
utc = calendar.timegm(clock.juliandate_to_utc(jd).utctimetuple())
gps = clock.utc_to_gps(utc)
zenith, azimuth = celestial.horizontal_to_zenithazimuth(
np.radians(base.sexagesimal_to_decimal(*altitude)),
np.radians(base.sexagesimal_to_decimal(*azi)))
ra, dec = celestial.zenithazimuth_to_equatorial(latitude, longitude,
gps, zenith, azimuth)
# Test eq_to_zenaz merely against IDL
zencalc, azcalc = celestial.equatorial_to_zenithazimuth(
latitude, longitude, gps, ra_expected, dec_expected)
self.assertAlmostEqual(ra, ra_expected, 1)
self.assertAlmostEqual(ra, ra_astropy, 1)
self.assertAlmostEqual(dec, dec_expected, 2)
self.assertAlmostEqual(dec, dec_astropy, 2)
self.assertAlmostEqual(zencalc, zenith, 1)
self.assertAlmostEqual(azcalc, azimuth, 2)
def test_against_hor2eq(self):
"""Check for consistent results with an IDL hor2eq example.
See EXAMPLE input and output here:
http://idlastro.gsfc.nasa.gov/ftp/pro/astro/hor2eq.pro
Observatory position for ``kpno`` from here:
http://idlastro.gsfc.nasa.gov/ftp/pro/astro/observatory.pro
"""
# IDL hor2eq
ra_expected = np.radians(3.30875)
dec_expected = np.radians(15.183416666666666)
# Astropy 1.0rc1
ra_astropy = np.radians(3.3094193224314625)
dec_astropy = np.radians(15.183757021354532)
# KPNO observatory
longitude = -111.6
latitude = 31.9633
# Observation time
jd = 2466879.7083333
# Altitude Azimuth
altitude = (37, 54, 41)
azi = (264, 55, 6)
# lst = clock.gmst_to_lst(clock.juliandate_to_gmst(jd), longitude)
# Matches LAST = +03 53 53.6 in the hor2eq.pro
# SAPPHiRE
utc = calendar.timegm(clock.juliandate_to_utc(jd).utctimetuple())
gps = clock.utc_to_gps(utc)
zenith, azimuth = celestial.horizontal_to_zenithazimuth(
np.radians(base.sexagesimal_to_decimal(*altitude)),
np.radians(base.sexagesimal_to_decimal(*azi)))
ra, dec = celestial.zenithazimuth_to_equatorial(
latitude, longitude, gps, zenith, azimuth)
# Test eq_to_zenaz merely against IDL
zencalc, azcalc = celestial.equatorial_to_zenithazimuth(
latitude, longitude, gps, ra_expected, dec_expected)
self.assertAlmostEqual(ra, ra_expected, 1)
self.assertAlmostEqual(ra, ra_astropy, 1)
self.assertAlmostEqual(dec, dec_expected, 2)
self.assertAlmostEqual(dec, dec_astropy, 2)
self.assertAlmostEqual(zencalc, zenith, 1)
self.assertAlmostEqual(azcalc, azimuth, 2)
def test_against_pyephem():
"""Check that Astropy gives consistent results with one PyEphem example.
PyEphem: http://rhodesmill.org/pyephem/
See example input and output here:
https://gist.github.com/zonca/1672906
https://github.com/phn/pytpm/issues/2#issuecomment-3698679
"""
print('PyEphem')
obstime = Time('2011-09-18 08:50:00')
location = EarthLocation(lon=Angle('-109d24m53.1s'),
lat=Angle('33d41m46.0s'),
height=0. * u.m)
# We are using the default pressure and temperature in PyEphem
altaz_frame = AltAz(obstime=obstime, location=location)
altaz = SkyCoord('6.8927d -60.7665d', frame=altaz_frame)
radec_actual = altaz.transform_to('icrs')
print('Astropy: ', radec_actual)
radec_expected = SkyCoord('196.497518d -4.569323d', frame='icrs') # EPHEM
print('Source: ', radec_expected)
# radec_expected = SkyCoord('196.496220d -4.569390d', frame='icrs') # HORIZON
distance = radec_actual.separation(radec_expected).to('arcsec')
# TODO: why is this difference so large?
# It currently is: 31.45187984720655 arcsec
assert distance < 1e3 * u.arcsec
# Add assert on current Astropy result so that we notice if something changes
radec_expected = SkyCoord('196.495372d -4.560694d', frame='icrs')
distance = radec_actual.separation(radec_expected).to('arcsec')
# Current value: 0.0031402822944751997 arcsec
#assert distance < 1 * u.arcsec
# SAPPHiRE
longitude = base.sexagesimal_to_decimal(-109, -24, -53.1)
latitude = base.sexagesimal_to_decimal(33, 41, 46.0)
utc = datetime.datetime(2011, 9, 18, 8, 50, 00)
elevation = np.radians(-60.7665)
azi = np.radians(6.8927)
gps = clock.utc_to_gps(calendar.timegm(utc.utctimetuple()))
zenith, azimuth = celestial.horizontal_to_zenithazimuth(elevation, azi)
ra, dec = celestial.zenithazimuth_to_equatorial(longitude, latitude, gps,
zenith, azimuth)
print('SAPPHiRE: ra=%f, dec=%f' % (np.degrees(ra), np.degrees(dec)))