def test_spherical_rotation():
"""
Test taken from JWST INS report - converts
JWST telescope (V2, V3) coordinates to RA, DEC.
"""
ra_ref = 165 # in deg
dec_ref = 54 # in deg
v2_ref = -503.654472 / 3600 # in deg
v3_ref = -318.742464 / 3600 # in deg
r0 = 37 # in deg
v2 = 210 # in deg
v3 = -75 # in deg
expected_ra_dec = (107.12810484789563, -35.97940247128502) # in deg
angles = np.array([v2_ref, -v3_ref, r0, dec_ref, -ra_ref])
axes = "zyxyz"
v2s = rotations.RotationSequence3D(angles, axes_order=axes)
x, y, z = rotations.spherical2cartesian(v2, v3)
x1, y1, z1 = v2s(x, y, z)
radec = rotations.cartesian2spherical(x1, y1, z1)
assert_allclose(radec, expected_ra_dec, atol=1e-10)
v2s = rotations.SphericalRotationSequence(angles, axes_order=axes)
radec = v2s(v2, v3)
assert_allclose(radec, expected_ra_dec, atol=1e-10)
def from_tree_transform(self, node):
angles = node['angles']
axes_order = node['axes_order']
rotation_type = node['rotation_type']
if rotation_type == 'cartesian':
return rotations.RotationSequence3D(angles, axes_order=axes_order)
elif rotation_type == 'spherical':
return rotations.SphericalRotationSequence(angles,
axes_order=axes_order)
else:
raise ValueError(f"Unrecognized rotation_type: {rotation_type}")
def from_yaml_tree_transform(self, node, tag, ctx):
from astropy.modeling import rotations
angles = node["angles"]
axes_order = node["axes_order"]
rotation_type = node["rotation_type"]
if rotation_type == "cartesian":
return rotations.RotationSequence3D(angles, axes_order=axes_order)
elif rotation_type == "spherical":
return rotations.SphericalRotationSequence(angles,
axes_order=axes_order)
else:
raise ValueError(f"Unrecognized rotation_type: {rotation_type}")
