ndcube.utils.wcs.array_indices_for_world_objects(wcs, axes=None)[source]

Calculate the array indices corresponding to each high level world object.

This function is to assist in comparing the return values from NDCube.axis_world_coords or world_to_pixel it returns a tuple of the same length as the output from those methods with each element being the array indices corresponding to those objects.

  • wcs (astropy.wcs.wcsapi.BaseHighLevelWCS) – The wcs object used to calculate world coordinates.

  • axes (iterable of int or str) – Axis number in numpy ordering or unique substring of wcs.world_axis_physical_types of axes for which real world coordinates are desired. axes=None implies all axes will be returned.


array_indices – For each world object, a tuple of array axes identified by their number. Array indices in each sub-tuple are not guaranteed to be ordered with respect to the arrays in the object, as the object could be an object like SkyCoord where there is a separation of the two coordinates. The array indices will be returned in the sub-tuple in array index order, i.e ascending.

Return type:

tuple of tuple of int