def test_from_altaz_needs_topos():
p = positionlib.ICRF([0.0, 0.0, 0.0])
with assert_raises(ValueError, 'the orientation of the horizon'):
p.from_altaz(alt_degrees=0, az_degrees=0)
def test_from_altaz_needs_topos():
p = positionlib.ICRF([0.0, 0.0, 0.0])
with assert_raises(ValueError, 'to compute an altazimuth position'):
p.from_altaz(alt_degrees=0, az_degrees=0)