def MakeNearRay( ipix, lr=None, observer_position=observer_position, collect=False ):
## reads data of LoS in constrained spherical volume around observer in z=0 snapshot
### provide lr = Lightray( dsz0 ) for pool computation
## write ray data to
filename = FileNearRay( ipix, model=model, npix=npix )
## skip if ray was produced already
if os.path.isfile( filename ):
print 'skip %i' % ipix,
return;
if lr is None:
lr = LightRay( dsz0 ) ## initialize trident.LightRay
for off in [ 0., 0.0001, -0.0001]: ## sometimes fails, when LoS is on axis. Try again with small offset
try:
direction = np.array( hp.pix2vec( nside, ipix) ) + off # shift to not move along edge of cells
start_position = path_length_code * direction + observer_position
lr.make_light_ray( ## compute LoS and save to .h5 file
start_position = start_position, # LoS starts at the edge and ends at observer
end_position = observer_position,
data_filename = filename,
fields = fields[:],
redshift = redshift_max_near, ## starting redshift, chosen to end at observer with z=0
use_peculiar_velocity=False, # do not correct redshift for doppler shift from peculiar velocity
)
break
except:
continue
if collect:
## write to collection file
### !!! not possible to write to same file in multi processing. Use separate function CollectRays
CollectRay( ipix )
def test_light_ray_cosmo_nonperiodic(self):
"""
This test generates a cosmological light ray using non-periodic segments
"""
lr = LightRay(COSMO_PLUS, 'Enzo', 0.0, 0.03)
lr.make_light_ray(seed=1234567, periodic=False,
fields=['temperature', 'density', 'H_number_density'],
data_filename='lightray.h5')
ds = load('lightray.h5')
compare_light_ray_solutions(lr, ds)
def test_light_ray_cosmo(self):
"""
This test generates a cosmological light ray
"""
lr = LightRay(COSMO_PLUS, 'Enzo', 0.0, 0.03)
lr.make_light_ray(
seed=1234567,
fields=['temperature', 'density', 'H_p0_number_density'],
data_filename='lightray.h5')
ds = load('lightray.h5')
compare_light_ray_solutions(lr, ds)
def test_light_ray_non_cosmo(self):
"""
This test generates a non-cosmological light ray
"""
lr = LightRay(COSMO_PLUS_SINGLE)
ray_start = [0,0,0]
ray_end = [1,1,1]
lr.make_light_ray(start_position=ray_start, end_position=ray_end,
fields=['temperature', 'density', 'H_number_density'],
data_filename='lightray.h5')
ds = load('lightray.h5')
compare_light_ray_solutions(lr, ds)
def test_light_ray_cosmo_nested(self):
"""
This test generates a cosmological light ray confing the ray to a subvolume
"""
left = np.ones(3) * 0.25
right = np.ones(3) * 0.75
lr = LightRay(COSMO_PLUS, 'Enzo', 0.0, 0.03)
lr.make_light_ray(seed=1234567, left_edge=left, right_edge=right,
fields=['temperature', 'density', 'H_number_density'],
data_filename='lightray.h5')
ds = load('lightray.h5')
compare_light_ray_solutions(lr, ds)
def test_light_ray_non_cosmo_from_dataset(self):
"""
This test generates a non-cosmological light ray created from an already
loaded dataset
"""
ds = load(COSMO_PLUS_SINGLE)
lr = LightRay(ds)
ray_start = [0,0,0]
ray_end = [1,1,1]
lr.make_light_ray(start_position=ray_start, end_position=ray_end,
fields=[('gas', 'temperature'),
('gas', 'density'),
('gas', 'H_p0_number_density')],
data_filename='lightray.h5')
ds = load('lightray.h5')
compare_light_ray_solutions(lr, ds)
def CreateLoSSegments( ipixs, redshift_snapshots=redshift_snapshots[:], redshift_max=redshift_max, ts=ts[:], redshift_accuracy=redshift_accuracy, seed=seed, force=False ):
## creates files with random segments of LoS data of ray through yt-TimeSeries ts that contains grid data of snapshots at redshift_snapshots
## ipixs is a list of the indices given to the rays, defines how many rays are produced
## if not forced to, produce ray only if its data isn't already written to file
if not force:
try:
with h5.File( LoS_observables_file, 'r' ) as f:
for ipix in ipixs[:]:
try:
tmp = f[ '/'.join( [ model, 'chopped', str(ipix), 'DM' + 'overestimate'*overestimate_SM] ) ]
ipixs.remove(ipix)
except:
pass
except:
pass
## prevent the case of call with empty ipixs
if len(ipixs) == 0:
return;
''' remove completely
## exclude constrained near ray, go to z=0 instead
try:
redshift_snapshots.remove( redshift_max_near )
except:
pass
'''
RS = np.random.RandomState( seed * ( 1 + ipixs[0] ) )
## index of earliest snapshot to be probed == number of snapshots to be probed
# n_snaps = np.where( np.round( redshift_snapshots, redshift_accuracy ) >= redshift_max )[0][0]
n_snaps = len( redshift_snapshots ) - 1
# redshift = redshift_max
n = np.zeros( len(ipixs) )
## for all snapshots, starting with the earliest
for i_snap in range(n_snaps)[::-1]:
## load snapshot
lr = LightRay( ts[i_snap] )
## set time when rays should enter the snapshot
redshift = redshift_snapshots[1+i_snap]
new = True
flags = np.ones( len(ipixs) ) ## flag whether more segments are needed
while np.any( flags ):
## create round of segments
for i_flag, ipix in enumerate(ipixs):
## skip those that finished current snapshot
if not flags[i_flag]:
continue
## in later rounds: for each, read final redshift from previous and continue with that
if not new:
redshift = h5.File( FilenameSegment( ipix, n[i_flag]-1 ) )['grid/redshift'].value[-1]
## in case redshift is past next snapshot, skip and deflag
if redshift <= redshift_snapshots[i_snap]: ###!!!!
flags[i_flag] = 0
continue
# print 'make segment from z=%.4f' % redshift
CreateSegment( lr, RS, redshift, n[i_flag], ipix )
n[i_flag] += 1
## round finished
new = False
