def v23tosky(input_model, wrap_v2_at=180, wrap_lon_at=360):
v2_ref = input_model.meta.wcsinfo.v2_ref / 3600
v3_ref = input_model.meta.wcsinfo.v3_ref / 3600
roll_ref = input_model.meta.wcsinfo.roll_ref
ra_ref = input_model.meta.wcsinfo.ra_ref
dec_ref = input_model.meta.wcsinfo.dec_ref
angles = np.array([v2_ref, -v3_ref, roll_ref, dec_ref, -ra_ref])
axes = "zyxyz"
rot = RotationSequence3D(angles, axes_order=axes)
# The sky rotation expects values in deg.
# This should be removed when models work with quantities.
m = ((Scale(1 / 3600) & Scale(1 / 3600)) | SphericalToCartesian(wrap_lon_at=wrap_v2_at)
| rot | CartesianToSpherical(wrap_lon_at=wrap_lon_at))
m.name = 'v23tosky'
return m
def _tpcorr_init(v2_ref, v3_ref, roll_ref):
s2c = SphericalToCartesian(name='s2c', wrap_lon_at=180)
c2s = CartesianToSpherical(name='c2s', wrap_lon_at=180)
unit_conv = Scale(1.0 / 3600.0, name='arcsec_to_deg_1D')
unit_conv = unit_conv & unit_conv
unit_conv.name = 'arcsec_to_deg_2D'
unit_conv_inv = Scale(3600.0, name='deg_to_arcsec_1D')
unit_conv_inv = unit_conv_inv & unit_conv_inv
unit_conv_inv.name = 'deg_to_arcsec_2D'
affine = AffineTransformation2D(name='tp_affine')
affine_inv = AffineTransformation2D(name='tp_affine_inv')
rot = RotationSequence3D([v2_ref, -v3_ref, roll_ref],
'zyx',
name='det_to_optic_axis')
rot_inv = rot.inverse
rot_inv.name = 'optic_axis_to_det'
# projection submodels:
c2tan = ((Mapping((0, 1, 2), name='xyz') / Mapping(
(0, 0, 0), n_inputs=3, name='xxx')) | Mapping((1, 2), name='xtyt'))
c2tan.name = 'Cartesian 3D to TAN'
tan2c = (Mapping((0, 0, 1), n_inputs=2, name='xtyt2xyz') |
(Const1D(1, name='one') & Identity(2, name='I(2D)')))
tan2c.name = 'TAN to cartesian 3D'
total_corr = (unit_conv | s2c | rot | c2tan | affine | tan2c | rot_inv
| c2s | unit_conv_inv)
total_corr.name = 'JWST tangent-plane linear correction. v1'
inv_total_corr = (unit_conv | s2c | rot | c2tan | affine_inv | tan2c
| rot_inv | c2s | unit_conv_inv)
inv_total_corr.name = 'Inverse JWST tangent-plane linear correction. v1'
# TODO
# re-enable circular inverse definitions once
# https://github.com/spacetelescope/asdf/issues/744 or
# https://github.com/spacetelescope/asdf/issues/745 are resolved.
#
# inv_total_corr.inverse = total_corr
total_corr.inverse = inv_total_corr
return total_corr
def test_v23_to_sky():
"""
Test taken from INS report.
"""
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 = [v2_ref, -v3_ref, r0, dec_ref, -ra_ref]
axes = "zyxyz"
rot = RotationSequence3D(angles, axes_order=axes)
v2s = SphericalToCartesian() | rot | CartesianToSpherical()
radec = v2s(v2, v3)
assert_allclose(radec, expected_ra_dec, atol=1e-10)