def _1d_correlation(pos, min_cut, max_cut, end_s=0.02, ns=15, n_randoms=1, n_cores=1):
"""
Does a 1d correlation in either redshift or comoving distance space.
"""
if pos.max() < 10.0:
A, g, t = sf.fit_selection_simple_z(pos)
else:
A, g, t = sf.fit_selection_simple(pos)
DD = _correlation_1d_DD_wrapper(pos1=pos, end_s=end_s, ns=ns, n_cores=n_cores)
print "Done DD"
RR = np.zeros((ns))
DR = np.zeros((ns))
print "made zeros"
for i in range(n_randoms):
rand_r = sf.create_radial_selection(A, g, t, min_cut, max_cut, len(pos))
if i == 0:
plt.hist(rand_r, normed=True)
plt.hist(pos, normed=True)
plt.show()
go_ahead = str(raw_input("do you like what you see?? [Y/n]"))
if go_ahead == 'n':
raise ValueError("Okay we'll stop then")
print len(rand_r)
RR += _correlation_1d_DD_wrapper(pos1=rand_r, end_s=end_s, ns=ns, n_cores=n_cores)
print "Done RR"
DR += _correlation_1d_DR_wrapper(pos1=pos, pos2=rand_r, end_s=end_s, ns=ns, n_cores=n_cores)
print "done DR"
RR /= n_randoms
DR /= n_randoms
#Use the Landy-Szalay Estimator
Corr = 1 + DD / RR - 2 * DR * (len(pos) - 1.0) / len(pos) / RR
#Calculate the centre of bins
s_bins = np.linspace(end_s / (2 * ns), end_s * (1 - 0.5 / ns), ns)
print "got to the end..."
print Corr
return s_bins.copy(), Corr.copy()
def radial_mock(self, method="EEP", N=None, bins=100,
new_lumfunc=False, min_acceptable=1, eps=0.01,
max_iter=10, selbins=100):
"""
Creates a random catalogue of particles based on a defined selection function. Only radial co-ords.
Ouput: radii :: length N vector (default length of survey) of radii
"""
z_min = self.survey_data['redshift'].min()
z_max = self.survey_data['redshift'].max()
if N is None:
N = self.N
if method is None:
radii = sf.create_radial_selection_simple(z_min, z_max, N)
else:
M, phi = self.lum_func(Np=bins, method=method,
new=new_lumfunc, min_acceptable=min_acceptable,
eps=eps, max_iter=max_iter)
s_of_z = sf.selection_of_z(selbins, phi, M, self.survey_data["mag_r"],
self.survey_data["absmag"],
self.survey_data["redshift"])
radii = sf.create_mock(s_of_z, z_min, z_max, N)
#Plot it
plt.clf()
plt.hist(radii, bins=100, normed=True, label="Mock")
plt.hist(self.survey_data['redshift'], bins=100, normed=True, label="Data")
plt.legend()
plt.savefig(self._dirs['SelectionFunction'] +
'N(z)_' + method + '_L' + str(bins)
+ "_S" + str(selbins) + '.' + self.plottype)
return radii
def selection_function(self, method="EEP", bins=None,
new_lumfunc=False, min_acceptable=1, eps=0.01,
max_iter=10, selbins=100):
"""
Calculate a selection function value for each galaxy.
INPUT PARAMETERS
method ["EEP"] -- A method with which to calculate the lumfunc. If None,
will use a simple parametrisation for the N(z) distribution.
bins [None] -- How many bins to use in the given method
new_lumfunc [False] -- Whether to force a new lumfunc calculation even if previous
results exist
new_selection [False] -- Whether to force a new selection function calcualtion even
if previous results exit.
min_acceptable -- Lowest acceptable number of galaxies per bin
eps -- Target uncertainty for convergence in EEP
max_iter -- Maximum iterations for EEP
"""
if method is None:
A, g, t = sf.fit_selection_simple(self.survey_data['c_dist'],
bins=bins, verbose=self.verbose)
self.survey_data['weight'] = 1.0 / sf.get_sel_from_nd(A, g, t)(self.survey_data['c_dist'])
#WRITE OUT A SIMPLE PLOT FOR CHECKING!
if not bins:
bins = utils.FD_bins(self.survey_data['c_dist'])
plt.clf()
plt.title("N(d) with selection function for Sample " + self.sample_name + " from " + self.survey_name)
hist, edges = np.histogram(self.survey_data['c_dist'], density=True, bins=bins)
centres = edges[:-1] + (edges[1] - edges[0]) / 2.0
plt.plot(centres, hist)
plt.plot(centres, sf.selection_simple(centres, A, g, t))
plt.xlabel("Comoving Distance")
plt.ylabel("Normalised Count")
plt.savefig(self._dirs['SelectionFunction'] + 'N(d)_' + str(bins) + "bins.eps")
plt.show()
self.selection_params = {'A':A, 'g':g, 't':t}
else:
M, phi = self.lum_func(Np=bins, method=method,
new=new_lumfunc, min_acceptable=min_acceptable,
eps=eps, max_iter=max_iter)
if selbins is None:
self.survey_data['weight'] = 1. / sf.selection_of_galaxies(phi, M,
self.survey_data['mag_r'],
self.survey_data["absmag"])
#Plot it up
plt.clf()
plt.plot(self.survey_data["redshift"], 1. / self.survey_data["weight"],
linestyle="None", marker='.', markersize=1)
plt.xlabel("Redshift")
plt.ylabel("Selection Function")
plt.yscale("log")
plt.savefig(self._dirs['SelectionFunction'] + 'SelectionFunction_' + method + '_' + str(bins) + '.' + self.plottype)
else:
s_of_z = sf.selection_of_z(selbins, phi, M, self.survey_data["mag_r"],
self.survey_data["absmag"],
self.survey_data["redshift"])
self.survey_data['weight'] = 1. / np.exp(s_of_z(self.survey_data['redshift']))
#Make a plot
z = np.linspace(self.survey_data['redshift'].min(),
self.survey_data['redshift'].max(),
1000)
plt.clf()
plt.plot(z, np.exp(s_of_z(z)))
plt.yscale('log')
plt.xlabel("Redshift")
plt.ylabel("Selection Function")
plt.savefig(self._dirs['SelectionFunction'] +
'SelectionFunctionAve_' + method + '_L' + str(bins)
+ "_S" + str(selbins) + '.' + self.plottype)
