def _xarray_affine_impl(obj):
sdims = spatial_dims(obj, relaxed=True)
if sdims is None:
return None, None
yy, xx = (obj[dim] for dim in sdims)
fallback_res = (coord.attrs.get('resolution', None) for coord in (xx, yy))
return affine_from_axis(xx.values, yy.values, fallback_res), sdims
def test_utils_affine_from_axis():
assert affine_from_axis(np.asarray([1.5, 2.5, 3.5]),
np.asarray([10.5, 11.5])) * (0, 0) == (1.0, 10.0)
assert affine_from_axis(np.asarray([1.5, 2.5, 3.5]),
np.asarray([10.5, 11.5])) * (2, 1) == (3, 11)
(sx, z1, tx, z2, sy, ty, *_) = affine_from_axis(np.asarray([1, 2, 3]),
np.asarray([10, 20]))
assert z1 == 0 and z2 == 0
assert sx == 1 and sy == 10
assert tx == 0.5 and ty == 5
(sx, _, tx, _, sy, ty, *_) = affine_from_axis(np.asarray([1]),
np.asarray([10, 20]), 1)
assert sx == 1 and sy == 10
assert tx == 0.5 and ty == 5
(sx, _, tx, _, sy, ty, *_) = affine_from_axis(np.asarray([1]),
np.asarray([10, 20]), (1, 1))
assert sx == 1 and sy == 10
assert tx == 0.5 and ty == 5
(sx, _, tx, _, sy, ty, *_) = affine_from_axis(np.asarray([1]),
np.asarray([10]), (2, 10))
assert sx == 2 and sy == 10
assert tx == 0 and ty == 5