def test_varying_transform_pc():
varying_matrix_lt = [
rotation_matrix(a)[:2, :2] for a in np.linspace(0, 90, 10)
] * u.arcsec
vct = VaryingCelestialTransform(crpix=(5, 5) * u.pix,
cdelt=(1, 1) * u.arcsec / u.pix,
crval_table=(0, 0) * u.arcsec,
pc_table=varying_matrix_lt,
lon_pole=180 * u.deg)
trans5 = vct.transform_at_index(5)
assert isinstance(trans5, CompoundModel)
# Verify that we have the 5th matrix in the series
affine = trans5.left.left.right
assert isinstance(affine, m.AffineTransformation2D)
assert u.allclose(affine.matrix, varying_matrix_lt[5])
# x.shape=(1,), y.shape=(1,), z.shape=(1,)
pixel = (0 * u.pix, 0 * u.pix, 5 * u.pix)
world = vct(*pixel)
assert np.array(world[0]).shape == ()
assert u.allclose(world, (359.99804329 * u.deg, 0.00017119 * u.deg))
assert u.allclose(vct.inverse(*world, 5 * u.pix),
pixel[:2],
atol=0.01 * u.pix)
def test_varying_transform_pc_unitless():
varying_matrix_lt = [
rotation_matrix(a)[:2, :2] for a in np.linspace(0, 90, 10)
]
vct = VaryingCelestialTransform(
crpix=(5, 5),
# without units everything is deg, so make this arcsec in deg
cdelt=((1, 1) * u.arcsec).to_value(u.deg),
crval_table=(0, 0),
pc_table=varying_matrix_lt,
lon_pole=180)
trans5 = vct.transform_at_index(5)
assert isinstance(trans5, CompoundModel)
# Verify that we have the 5th matrix in the series
affine = trans5.left.left.right
assert isinstance(affine, m.AffineTransformation2D)
assert u.allclose(affine.matrix, varying_matrix_lt[5])
pixel = (0, 0, 5)
world = vct(*pixel)
assert np.allclose(world, (359.99804329, 0.00017119))
assert np.allclose(vct.inverse(*world, 5), pixel[:2], atol=0.01)
def test_varying_transform_pc_shapes(pixel, lon_shape):
varying_matrix_lt = [
rotation_matrix(a)[:2, :2] for a in np.linspace(0, 90, 10)
] * u.arcsec
vct = VaryingCelestialTransform(crpix=(5, 5) * u.pix,
cdelt=(1, 1) * u.arcsec / u.pix,
crval_table=(0, 0) * u.arcsec,
pc_table=varying_matrix_lt,
lon_pole=180 * u.deg)
world = vct(*pixel)
assert np.array(world[0]).shape == lon_shape
new_pixel = vct.inverse(*world, pixel[-1])
assert u.allclose(new_pixel,
np.broadcast_arrays(*pixel, subok=True)[:2],
atol=0.01 * u.pix)
def test_varying_transform_crval():
crval_table = ((0, 1), (2, 3), (4, 5)) * u.arcsec
vct = VaryingCelestialTransform(crpix=(5, 5) * u.pix,
cdelt=(1, 1) * u.arcsec / u.pix,
crval_table=crval_table,
pc_table=np.identity(2) * u.arcsec,
lon_pole=180 * u.deg)
trans2 = vct.transform_at_index(2)
assert isinstance(trans2, CompoundModel)
# Verify that we have the 2nd crval pair in the series
crval1 = trans2.right.lon
crval2 = trans2.right.lat
assert u.allclose(crval1, crval_table[2][0])
assert u.allclose(crval2, crval_table[2][1])
pixel = (0 * u.pix, 0 * u.pix, 2 * u.pix)
world = vct(*pixel)
assert u.allclose(world, (3.59999722e+02, 2.78325906e-13) * u.deg)
assert u.allclose(vct.inverse(*world, 2 * u.pix),
pixel[:2],
atol=0.01 * u.pix)