def test__different_number_of_slices_between_planes(self):
ordered_plane_redshifts = [(1.0 / 3.0), (2.0 / 3.0), 1.0, 1.25, 1.5, 1.75, 2.0]
galaxies = [
ag.Galaxy(redshift=0.1),
ag.Galaxy(redshift=0.2),
ag.Galaxy(redshift=1.25),
ag.Galaxy(redshift=1.35),
ag.Galaxy(redshift=1.45),
ag.Galaxy(redshift=1.55),
ag.Galaxy(redshift=1.9),
]
galaxies_in_redshift_ordered_planes = galaxies_in_redshift_ordered_planes_from(
galaxies=galaxies, plane_redshifts=ordered_plane_redshifts
)
assert galaxies_in_redshift_ordered_planes[0][0].redshift == 0.1
assert galaxies_in_redshift_ordered_planes[0][1].redshift == 0.2
assert galaxies_in_redshift_ordered_planes[1] == []
assert galaxies_in_redshift_ordered_planes[2] == []
assert galaxies_in_redshift_ordered_planes[3][0].redshift == 1.25
assert galaxies_in_redshift_ordered_planes[3][1].redshift == 1.35
assert galaxies_in_redshift_ordered_planes[4][0].redshift == 1.45
assert galaxies_in_redshift_ordered_planes[4][1].redshift == 1.55
assert galaxies_in_redshift_ordered_planes[6][0].redshift == 1.9
def test__6_galaxies_producing_4_planes__galaxy_redshift_match_planes(self):
g0 = ag.Galaxy(redshift=1.0)
g1 = ag.Galaxy(redshift=1.0)
g2 = ag.Galaxy(redshift=0.1)
g3 = ag.Galaxy(redshift=1.05)
g4 = ag.Galaxy(redshift=0.95)
g5 = ag.Galaxy(redshift=1.05)
galaxies = [g0, g1, g2, g3, g4, g5]
ordered_plane_redshifts = [0.1, 0.95, 1.0, 1.05]
galaxies_in_redshift_ordered_planes = galaxies_in_redshift_ordered_planes_from(
galaxies=galaxies, plane_redshifts=ordered_plane_redshifts
)
assert galaxies_in_redshift_ordered_planes[0][0].redshift == 0.1
assert galaxies_in_redshift_ordered_planes[1][0].redshift == 0.95
assert galaxies_in_redshift_ordered_planes[2][0].redshift == 1.0
assert galaxies_in_redshift_ordered_planes[2][1].redshift == 1.0
assert galaxies_in_redshift_ordered_planes[3][0].redshift == 1.05
assert galaxies_in_redshift_ordered_planes[3][1].redshift == 1.05
assert galaxies_in_redshift_ordered_planes[0] == [g2]
assert galaxies_in_redshift_ordered_planes[1] == [g4]
assert galaxies_in_redshift_ordered_planes[2] == [g0, g1]
assert galaxies_in_redshift_ordered_planes[3] == [g3, g5]
def from_galaxies(cls, galaxies, cosmology=cosmo.Planck15):
plane_redshifts = plane_util.ordered_plane_redshifts_from(
galaxies=galaxies)
galaxies_in_planes = plane_util.galaxies_in_redshift_ordered_planes_from(
galaxies=galaxies, plane_redshifts=plane_redshifts)
planes = []
for plane_index in range(0, len(plane_redshifts)):
planes.append(pl.Plane(galaxies=galaxies_in_planes[plane_index]))
return Tracer(planes=planes, cosmology=cosmology)
def test_3_galaxies_x2_same_redshift__order_is_size_2_with_redshifts__plane_match_galaxy_redshifts(
self, ):
galaxies = [
ag.Galaxy(redshift=1.0),
ag.Galaxy(redshift=1.0),
ag.Galaxy(redshift=0.1),
]
ordered_plane_redshifts = [0.1, 1.0]
galaxies_in_redshift_ordered_planes = galaxies_in_redshift_ordered_planes_from(
galaxies=galaxies, plane_redshifts=ordered_plane_redshifts)
assert galaxies_in_redshift_ordered_planes[0][0].redshift == 0.1
assert galaxies_in_redshift_ordered_planes[1][0].redshift == 1.0
assert galaxies_in_redshift_ordered_planes[1][1].redshift == 1.0
def test__3_galaxies_reordered_in_ascending_redshift__planes_match_galaxy_redshifts(
self, ):
galaxies = [
ag.Galaxy(redshift=2.0),
ag.Galaxy(redshift=1.0),
ag.Galaxy(redshift=0.1),
]
ordered_plane_redshifts = [0.1, 1.0, 2.0]
galaxies_in_redshift_ordered_planes = galaxies_in_redshift_ordered_planes_from(
galaxies=galaxies, plane_redshifts=ordered_plane_redshifts)
assert galaxies_in_redshift_ordered_planes[0][0].redshift == 0.1
assert galaxies_in_redshift_ordered_planes[1][0].redshift == 1.0
assert galaxies_in_redshift_ordered_planes[2][0].redshift == 2.0
def test__galaxy_redshifts_dont_match_plane_redshifts__tied_to_nearest_plane(self):
ordered_plane_redshifts = [0.5, 1.0, 2.0, 3.0]
galaxies = [
ag.Galaxy(redshift=0.2),
ag.Galaxy(redshift=0.4),
ag.Galaxy(redshift=0.8),
ag.Galaxy(redshift=1.2),
ag.Galaxy(redshift=2.9),
]
galaxies_in_redshift_ordered_planes = galaxies_in_redshift_ordered_planes_from(
galaxies=galaxies, plane_redshifts=ordered_plane_redshifts
)
assert galaxies_in_redshift_ordered_planes[0][0].redshift == 0.2
assert galaxies_in_redshift_ordered_planes[0][1].redshift == 0.4
assert galaxies_in_redshift_ordered_planes[1][0].redshift == 0.8
assert galaxies_in_redshift_ordered_planes[1][1].redshift == 1.2
assert galaxies_in_redshift_ordered_planes[2] == []
assert galaxies_in_redshift_ordered_planes[3][0].redshift == 2.9
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)
