def test_get_observer_units(self):
"""Alt,az must have angular units for get_observer()"""
t = astropy.time.Time('2020-01-01')
with self.assertRaises(TypeError):
utils.get_observer(t, alt=1, az=1)
with self.assertRaises(u.UnitsError):
utils.get_observer(t, alt=1 * u.m, az=1 * u.m)
def test_get_observer_args(self):
"""Must provide both alt and az to get_observer()"""
t = astropy.time.Time('2020-01-01')
with self.assertRaises(ValueError):
utils.get_observer(t, alt=0 * u.deg)
with self.assertRaises(ValueError):
utils.get_observer(t, az=0 * u.deg)
def test_get_observer_from_sky(self):
"""Check (alt,az) -> (ra,dec) against JPL Horizons"""
ra, dec = self.table['ra'], self.table['dec']
alt, az = self.table['alt'], self.table['az']
when = astropy.time.Time(self.table['jd'], format='jd')
sky = astropy.coordinates.ICRS(ra=ra * u.deg, dec=dec * u.deg)
true_altaz = utils.get_observer(when, alt * u.deg, az * u.deg)
obs_altaz = sky.transform_to(utils.get_observer(when))
sep = true_altaz.separation(obs_altaz).to(u.arcsec).value
# Opening angle between true and observed (alt,az) unit vectors
# must be within 30 arcsec.
self.assertTrue(np.max(np.fabs(sep)) < 30)
def test_get_observer_time(self):
"""Must pass arg convertible to astropy Time to get_observer()"""
utils.get_observer('2020-01-01')
utils.get_observer(datetime.datetime(2020, 1, 1, 0, 0))
with self.assertRaises(ValueError):
utils.get_observer(datetime.date(2020, 1, 1))
with self.assertRaises(ValueError):
utils.get_observer(50000.)