def test_tau_instant():
"""Check the optical depth we get using the WMAP z_reion.
"""
dz = 0.1
z = numpy.arange(80., 0. - 1.5 * dz, -1. * dz)
# Can't match WMAP7 optical depths exactly. Need to look into new
# treatment in CAMB as mentioned in the WMAP7 paper (see
# parameters.py).
cosmos = [
cparam.WMAP7_BAO_H0_mean(flat=True),
cparam.WMAP7_ML(flat=True),
cparam.WMAP5_BAO_SN_mean(flat=True),
cparam.WMAP5_ML(flat=True),
cparam.WMAP5_mean(flat=True)
]
# The WMAP5 numbers apparently assume He is neutral, while WMAP7
# includes simultaneous singly ionized He plus Helium (double)
# reionization at z=3.5.
x_ionHe_list = [1.0, 1.0, 0, 0, 0]
z_rHe_list = [3.5, 3.5, None, None, None] #[3.5, None, None, None]
for cosmo in cosmos:
# Fully ionized H
x_ionH = 1.0
# He ionization with H?
x_ionHe = x_ionHe_list.pop(0)
# Redshift for Helium double reionization?
z_rHe = z_rHe_list.pop(0)
zr = cosmo['z_reion']
tau_zr = cosmo['tau']
tau_calc = cr.optical_depth_instant(zr,
x_ionH=x_ionH,
x_ionHe=x_ionHe,
z_rHe=z_rHe,
verbose=1,
**cosmo)
print "z_r = %f, testing tau:" % zr,
print tu.fractional_diff_string(tau_zr, tau_calc, 3)
ntest.assert_approx_equal(tau_calc,
tau_zr,
significant=2,
err_msg="Optical depth doesn't match WMAP")
def test_t_0():
"""Check the age of the universe we get using WMAP cosmologies.
We only find agreement to 3 sig figs, not the 4 specified in the
WMAP paper.
The results of test_age.py show that we're doing the integral
correctly, so I think the problem is that we're not taking into
account some of the higher-order effects included in the WMAP
numbers.
"""
dz = 0.1
z = numpy.arange(80., 0. - 1.5 * dz, -1. * dz)
flat = True
cosmos = [
cparam.WMAP7_BAO_H0_mean(flat=True),
cparam.WMAP7_ML(flat=True),
cparam.WMAP5_BAO_SN_mean(flat=True),
cparam.WMAP5_ML(flat=True),
cparam.WMAP5_mean(flat=True)
]
for cosmo in cosmos:
age = cd.age(0.0, **cosmo)
age_flat = cd.age_flat(0.0, **cosmo)
gyr = 1e9 * cc.yr_s
age /= gyr
age_flat /= gyr
print "integrated age: ",
print tu.fractional_diff_string(age, cosmo['t_0'], 4)
ntest.assert_approx_equal(age,
cosmo['t_0'],
significant=3,
err_msg="Integrated age doesn't match WMAP")
print "analytical age: ",
print tu.fractional_diff_string(age_flat, cosmo['t_0'], 4)
ntest.assert_approx_equal(age_flat,
cosmo['t_0'],
significant=3,
err_msg="Analytical age doesn't match WMAP")
from __future__ import absolute_import, division, print_function
import numpy
import cosmolopy.perturbation as cp
import cosmolopy.parameters as cparam
import pylab
# Get WMAP5 cosmological parameters.
cosmo = cparam.WMAP5_BAO_SN_mean()
# Set up an array of z values.
z = numpy.arange(6.0, 20.0, 0.1)
# Calculate collapse fraction.
f_col = cp.collapse_fraction(*cp.sig_del(1e4, z, **cosmo))
pylab.figure(figsize=(8, 6))
pylab.plot(z, f_col)
pylab.xlabel('z')
pylab.ylabel(r'$f_\mathrm{col}$')
pylab.show()