def test_absorption_spectrum_non_cosmo(self):
"""
This test generates an absorption spectrum from a simple light ray on a
grid dataset
"""
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=[('gas', 'temperature'),
('gas', 'density'),
('gas', 'H_p0_number_density')],
data_filename='lightray.h5')
sp = AbsorptionSpectrum(1200.0, 1300.0, 10001)
my_label = 'HI Lya'
field = ('gas', 'H_p0_number_density')
wavelength = 1215.6700 # Angstromss
f_value = 4.164E-01
gamma = 6.265e+08
mass = 1.00794
sp.add_line(my_label, field, wavelength, f_value,
gamma, mass, label_threshold=1.e10)
filename = "spectrum.h5"
wavelength, flux = sp.make_spectrum('lightray.h5',
output_file=filename,
output_absorbers_file='lines.txt',
use_peculiar_velocity=True)
return filename
def test_absorption_spectrum_with_continuum(self):
"""
This test generates an absorption spectrum from a simple light ray on a
grid dataset and adds Lyman alpha and Lyman continuum to it
"""
ds = load(ISO_GALAXY)
lr = LightRay(ds)
ray_start = ds.domain_left_edge
ray_end = ds.domain_right_edge
lr.make_light_ray(
start_position=ray_start,
end_position=ray_end,
fields=['temperature', 'density', 'H_number_density'],
data_filename='lightray.h5')
sp = AbsorptionSpectrum(800.0, 1300.0, 5001)
my_label = 'HI Lya'
field = 'H_number_density'
wavelength = 1215.6700 # Angstromss
f_value = 4.164E-01
gamma = 6.265e+08
mass = 1.00794
sp.add_line(my_label,
field,
wavelength,
f_value,
gamma,
mass,
label_threshold=1.e10)
my_label = 'Ly C'
field = 'H_number_density'
wavelength = 912.323660 # Angstroms
normalization = 1.6e17
index = 3.0
sp.add_continuum(my_label, field, wavelength, normalization, index)
filename = "spectrum.h5"
wavelength, flux = sp.make_spectrum('lightray.h5',
output_file=filename,
line_list_file='lines.txt',
use_peculiar_velocity=True)
return filename
def test_absorption_spectrum_cosmo(self):
"""
This test generates an absorption spectrum from a compound light ray on a
grid dataset
"""
lr = LightRay(COSMO_PLUS, 'Enzo', 0.0, 0.03)
lr.make_light_ray(
seed=1234567,
fields=['temperature', 'density', 'H_number_density'],
data_filename='lightray.h5')
sp = AbsorptionSpectrum(900.0, 1800.0, 10000)
my_label = 'HI Lya'
field = 'H_number_density'
wavelength = 1215.6700 # Angstromss
f_value = 4.164E-01
gamma = 6.265e+08
mass = 1.00794
sp.add_line(my_label,
field,
wavelength,
f_value,
gamma,
mass,
label_threshold=1.e10)
my_label = 'HI Lya'
field = 'H_number_density'
wavelength = 912.323660 # Angstroms
normalization = 1.6e17
index = 3.0
sp.add_continuum(my_label, field, wavelength, normalization, index)
filename = "spectrum.h5"
wavelength, flux = sp.make_spectrum('lightray.h5',
output_file=filename,
line_list_file='lines.txt',
use_peculiar_velocity=True)
return filename
def test_absorption_spectrum_fits(self):
"""
This test generates an absorption spectrum and saves it as a fits file.
"""
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')
sp = AbsorptionSpectrum(900.0, 1800.0, 10000)
my_label = 'HI Lya'
field = 'H_number_density'
wavelength = 1215.6700 # Angstromss
f_value = 4.164E-01
gamma = 6.265e+08
mass = 1.00794
sp.add_line(my_label,
field,
wavelength,
f_value,
gamma,
mass,
label_threshold=1.e10)
my_label = 'HI Lya'
field = 'H_number_density'
wavelength = 912.323660 # Angstroms
normalization = 1.6e17
index = 3.0
sp.add_continuum(my_label, field, wavelength, normalization, index)
wavelength, flux = sp.make_spectrum('lightray.h5',
output_file='spectrum.fits',
line_list_file='lines.txt',
use_peculiar_velocity=True)
def test_equivalent_width_conserved(self):
"""
This tests that the equivalent width of the optical depth is conserved
regardless of the bin width employed in wavelength space.
Unresolved lines should still deposit optical depth into the spectrum.
"""
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')
my_label = 'HI Lya'
field = 'H_number_density'
wave = 1215.6700 # Angstromss
f_value = 4.164E-01
gamma = 6.265e+08
mass = 1.00794
lambda_min = 1200
lambda_max = 1300
lambda_bin_widths = [1e-3, 1e-2, 1e-1, 1e0, 1e1]
total_tau = []
for lambda_bin_width in lambda_bin_widths:
n_lambda = ((lambda_max - lambda_min) / lambda_bin_width) + 1
sp = AbsorptionSpectrum(lambda_min=lambda_min,
lambda_max=lambda_max,
n_lambda=n_lambda)
sp.add_line(my_label, field, wave, f_value, gamma, mass)
wavelength, flux = sp.make_spectrum('lightray.h5')
total_tau.append((lambda_bin_width * sp.tau_field).sum())
# assure that the total tau values are all within 1e-3 of each other
for tau in total_tau:
assert_almost_equal(tau, total_tau[0], 3)
def test_absorption_spectrum_with_zero_field(self):
"""
This test generates an absorption spectrum with some
particle dataset
"""
ds = load(FIRE)
lr = LightRay(ds)
# Define species and associated parameters to add to continuum
# Parameters used for both adding the transition to the spectrum
# and for fitting
# Note that for single species that produce multiple lines
# (as in the OVI doublet), 'numLines' will be equal to the number
# of lines, and f,gamma, and wavelength will have multiple values.
HI_parameters = {
'name': 'HI',
'field': 'H_number_density',
'f': [.4164],
'Gamma': [6.265E8],
'wavelength': [1215.67],
'mass': 1.00794,
'numLines': 1,
'maxN': 1E22,
'minN': 1E11,
'maxb': 300,
'minb': 1,
'maxz': 6,
'minz': 0,
'init_b': 30,
'init_N': 1E14
}
species_dicts = {'HI': HI_parameters}
# Get all fields that need to be added to the light ray
fields = [('gas', 'temperature')]
for s, params in species_dicts.items():
fields.append(params['field'])
# With a single dataset, a start_position and
# end_position or trajectory must be given.
# Trajectory should be given as (r, theta, phi)
lr.make_light_ray(start_position=ds.arr([0., 0., 0.], 'unitary'),
end_position=ds.arr([1., 1., 1.], 'unitary'),
solution_filename='test_lightraysolution.txt',
data_filename='test_lightray.h5',
fields=fields)
# Create an AbsorptionSpectrum object extending from
# lambda = 900 to lambda = 1800, with 10000 pixels
sp = AbsorptionSpectrum(900.0, 1400.0, 50000)
# Iterate over species
for s, params in species_dicts.items():
# Iterate over transitions for a single species
for i in range(params['numLines']):
# Add the lines to the spectrum
sp.add_line(s,
params['field'],
params['wavelength'][i],
params['f'][i],
params['Gamma'][i],
params['mass'],
label_threshold=1.e10)
# Make and save spectrum
wavelength, flux = sp.make_spectrum('test_lightray.h5',
output_file='test_spectrum.h5',
line_list_file='test_lines.txt',
use_peculiar_velocity=True)