def convertlineartostokes(vis): """Convert linear polarisations (XX, XY, YX, YY) into Stokes parameters. Args: vis (obj): ARL visibility data. Returns: vis: Converted visibility data. """ vis.data['vis'] = convert_linear_to_stokes(vis.data['vis'], polaxis=1) vis.polarisation_frame = PolarisationFrame('stokesIQUV') return vis
def convert_polimage_to_stokes(im: Image): """Convert a polarisation image to stokes (complex) """ assert type(im) == Image assert im.data.dtype == 'complex' if im.polarisation_frame == PolarisationFrame('linear'): cimarr = convert_linear_to_stokes(im.data) return create_image_from_array(cimarr, im.wcs, PolarisationFrame('stokesIQUV')) elif im.polarisation_frame == PolarisationFrame('circular'): cimarr = convert_circular_to_stokes(im.data) return create_image_from_array(cimarr, im.wcs, PolarisationFrame('stokesIQUV')) else: raise ValueError("Cannot convert %s to stokes" % (im.polarisation_frame.type))