def test_box_coordinates():
"""Check that pixel and frequency coordinates are returned."""
# Realise Gaussian box
np.random.seed(22)
box = CosmoBox(cosmo=default_cosmo,
box_scale=(1e3, 1e3, 1e3),
nsamp=16,
realise_now=True,
redshift=0.8)
# Check pixel array
ang_x, ang_y = box.pixel_array()
ang_x2, ang_y2 = box.pixel_array(redshift=0.82)
# ^Higher z, so further away, so smaller angle
# Check for valid output
assert np.all(~np.isnan(ang_x))
assert np.all(~np.isnan(ang_y))
assert np.all(~np.isnan(ang_x2))
assert np.all(~np.isnan(ang_y2))
# Square box => equal pixel sizes
assert np.isclose(ang_x[1] - ang_x[0], ang_y[1] - ang_y[0])
# Check that higher redshift pixels are smaller
assert ang_x[1] - ang_x[0] > ang_x2[1] - ang_x2[0]
assert ang_y[1] - ang_y[0] > ang_y2[1] - ang_y2[0]
# Check that frequency array goes in descending order (highest z coord =>
# lowest frequency)
assert np.all(np.diff(box.freq_array()) < 0.) # negative differences
assert np.all(
np.diff(box.freq_array(redshift=2.)) < 0.) # negative differences
#-------------------------------------------------------------------------------
# Add foregrounds
#-------------------------------------------------------------------------------
print("(2) Adding foregrounds...")
t0 = time.time()
# Create new foreground model
fg = ForegroundModel(box)
fg_map = fg.realise_foreground_amp(amp=57.,
beta=1.1,
monopole=10.,
smoothing_scale=4.,
redshift=box.redshift) # in mK
# Construct spectral index map
ang_x, ang_y = box.pixel_array(redshift=box.redshift)
alpha = fg.realise_spectral_index(mean_spec_idx=2.07,
std_spec_idx=0.0002,
smoothing_scale=15.,
redshift=box.redshift)
# Construct foreground datacube
fg_cube = fg.construct_cube(fg_map,
alpha,
freq_ref=130.,
redshift=box.redshift)
# Add to data cube
data_cube = signal_cube + fg_cube
print("\t(2) Adding foregrounds complete (%3.3f sec)" % (time.time() - t0))