def test__from_main_plane_redshifts_and_slices(self): ordered_plane_redshifts = ordered_plane_redshifts_with_slicing_from( lens_redshifts=[1.0], source_plane_redshift=3.0, planes_between_lenses=[1, 1], ) assert ordered_plane_redshifts == [0.5, 1.0, 2.0]
def test__different_number_of_slices_between_planes(self): ordered_plane_redshifts = ordered_plane_redshifts_with_slicing_from( lens_redshifts=[1.0], source_plane_redshift=2.0, planes_between_lenses=[2, 3], ) assert ordered_plane_redshifts == [ (1.0 / 3.0), (2.0 / 3.0), 1.0, 1.25, 1.5, 1.75, ]
def test__if_number_of_input_slices_is_not_equal_to_number_of_plane_intervals__raises_errror( self, ): with pytest.raises(exc.PlaneException): ordered_plane_redshifts_with_slicing_from( lens_redshifts=[1.0], source_plane_redshift=2.0, planes_between_lenses=[2, 3, 1], ) with pytest.raises(exc.PlaneException): ordered_plane_redshifts_with_slicing_from( lens_redshifts=[1.0], source_plane_redshift=2.0, planes_between_lenses=[2], ) with pytest.raises(exc.PlaneException): ordered_plane_redshifts_with_slicing_from( lens_redshifts=[1.0, 3.0], source_plane_redshift=2.0, planes_between_lenses=[2], )
def sliced_tracer_from_lens_line_of_sight_and_source_galaxies( cls, lens_galaxies, line_of_sight_galaxies, source_galaxies, planes_between_lenses, cosmology=cosmo.Planck15, ): """Ray-tracer for a lens system with any number of planes. The redshift of these planes are specified by the input parameters *lens_redshifts* and \ *slices_between_main_planes*. Every galaxy is placed in its closest plane in redshift-space. To perform multi-plane ray-tracing, a cosmology must be supplied so that deflection-angles can be rescaled \ according to the lens-geometry of the multi-plane system. All galaxies input to the tracer must therefore \ have redshifts. This tracer has only one grid (see gridStack) which is used for ray-tracing. Parameters ---------- lens_galaxies : [Galaxy] The list of galaxies in the ray-tracing calculation. image_plane_grid : grid_stacks.GridStack The image-plane grid which is traced. (includes the grid, sub-grid, blurring-grid, etc.). planes_between_lenses : [int] The number of slices between each main plane. The first entry in this list determines the number of slices \ between Earth (redshift 0.0) and main plane 0, the next between main planes 0 and 1, etc. border : masks.GridBorder The border of the grid, which is used to relocate demagnified traced pixels to the \ source-plane borders. cosmology : astropy.cosmology The cosmology of the ray-tracing calculation. """ lens_redshifts = plane_util.ordered_plane_redshifts_from( galaxies=lens_galaxies) plane_redshifts = plane_util.ordered_plane_redshifts_with_slicing_from( lens_redshifts=lens_redshifts, planes_between_lenses=planes_between_lenses, source_plane_redshift=source_galaxies[0].redshift, ) galaxies_in_planes = plane_util.galaxies_in_redshift_ordered_planes_from( galaxies=lens_galaxies + line_of_sight_galaxies, plane_redshifts=plane_redshifts, ) plane_redshifts.append(source_galaxies[0].redshift) galaxies_in_planes.append(source_galaxies) planes = [] for plane_index in range(0, len(plane_redshifts)): planes.append( pl.Plane( redshift=plane_redshifts[plane_index], galaxies=galaxies_in_planes[plane_index], )) return Tracer(planes=planes, cosmology=cosmology)