def test_against_pytpm_doc_example(): """ Check that Astropy's Ecliptic systems give answers consistent with pyTPM Currently this is only testing against the example given in the pytpm docs """ fk5_in = SkyCoord('12h22m54.899s', '15d49m20.57s', frame=FK5(equinox='J2000')) pytpm_out = BarycentricMeanEcliptic(lon=178.78256462*u.deg, lat=16.7597002513*u.deg, equinox='J2000') astropy_out = fk5_in.transform_to(pytpm_out) assert pytpm_out.separation(astropy_out) < (1*u.arcsec)
def test_against_pytpm_doc_example(): """ Check that Astropy's Ecliptic systems give answers consistent with pyTPM Currently this is only testing against the example given in the pytpm docs """ fk5_in = SkyCoord('12h22m54.899s', '15d49m20.57s', frame=FK5(equinox='J2000')) pytpm_out = BarycentricMeanEcliptic(lon=178.78256462*u.deg, lat=16.7597002513*u.deg, equinox='J2000') astropy_out = fk5_in.transform_to(pytpm_out) assert pytpm_out.separation(astropy_out) < (1*u.arcsec)
def test_arraytransforms(): """ Test that transforms to/from ecliptic coordinates work on array coordinates (not testing for accuracy.) """ ra = np.ones((4, ), dtype=float) * u.deg dec = 2 * np.ones((4, ), dtype=float) * u.deg distance = np.ones((4, ), dtype=float) * u.au test_icrs = ICRS(ra=ra, dec=dec, distance=distance) test_gcrs = GCRS(test_icrs.data) bary_arr = test_icrs.transform_to(BarycentricMeanEcliptic()) assert bary_arr.shape == ra.shape helio_arr = test_icrs.transform_to(HeliocentricMeanEcliptic()) assert helio_arr.shape == ra.shape geo_arr = test_gcrs.transform_to(GeocentricMeanEcliptic()) assert geo_arr.shape == ra.shape # now check that we also can go back the other way without shape problems bary_icrs = bary_arr.transform_to(ICRS()) assert bary_icrs.shape == test_icrs.shape helio_icrs = helio_arr.transform_to(ICRS()) assert helio_icrs.shape == test_icrs.shape geo_gcrs = geo_arr.transform_to(GCRS()) assert geo_gcrs.shape == test_gcrs.shape
def test_roundtrip_scalar(): icrs = ICRS(ra=1 * u.deg, dec=2 * u.deg, distance=3 * u.au) gcrs = GCRS(icrs.cartesian) bary = icrs.transform_to(BarycentricMeanEcliptic()) helio = icrs.transform_to(HeliocentricMeanEcliptic()) geo = gcrs.transform_to(GeocentricMeanEcliptic()) bary_icrs = bary.transform_to(ICRS()) helio_icrs = helio.transform_to(ICRS()) geo_gcrs = geo.transform_to(GCRS()) assert quantity_allclose(bary_icrs.cartesian.xyz, icrs.cartesian.xyz) assert quantity_allclose(helio_icrs.cartesian.xyz, icrs.cartesian.xyz) assert quantity_allclose(geo_gcrs.cartesian.xyz, gcrs.cartesian.xyz)
def test_ecliptic_heliobary(): """ Check that the ecliptic transformations for heliocentric and barycentric at least more or less make sense """ icrs = ICRS(1 * u.deg, 2 * u.deg, distance=1.5 * R_sun) bary = icrs.transform_to(BarycentricMeanEcliptic()) helio = icrs.transform_to(HeliocentricMeanEcliptic()) # make sure there's a sizable distance shift - in 3d hundreds of km, but # this is 1D so we allow it to be somewhat smaller assert np.abs(bary.distance - helio.distance) > 1 * u.km # now make something that's got the location of helio but in bary's frame. # this is a convenience to allow `separation` to work as expected helio_in_bary_frame = bary.realize_frame(helio.cartesian) assert bary.separation(helio_in_bary_frame) > 1 * u.arcmin