vide_public/python_source/backend/surveyTools.py

129 lines
4 KiB
Python

#+
# VIDE -- Void IDentification and Examination -- ./python_tools/vide/apTools/chi2/cosmologyTools.py
# Copyright (C) 2010-2014 Guilhem Lavaux
# Copyright (C) 2011-2014 P. M. Sutter
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License.
#
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#+
# a suite of functions to compute expansion rates, angular diameter
# distances, and expected void stretching
import numpy as np
import healpy as healpy
import os
from backend import *
__all__=['getSurveyProps', 'getNside', 'figureOutMask', 'findEdgeGalaxies']
# -----------------------------------------------------------------------------
# returns the volume and galaxy density for a given redshit slice
def getSurveyProps(maskFile, zmin, zmax, selFunMin, selFunMax, portion, selectionFuncFile=None, useComoving=False):
LIGHT_SPEED = 299792.458
mask = healpy.read_map(maskFile)
area = (1.*np.size(np.where(mask > 0)) / np.size(mask)) * 4.*np.pi
if useComoving:
zmin = LIGHT_SPEED/100.*angularDiameter(zmin, Om=0.27)
zmax = LIGHT_SPEED/100.*angularDiameter(zmax, Om=0.27)
selFunMin = LIGHT_SPEED/100.*angularDiameter(selFunMin, Om=0.27)
selFunMax = LIGHT_SPEED/100.*angularDiameter(selFunMax, Om=0.27)
else:
zmin = zmin * 3000
zmax = zmax * 3000
selFunMin *= 3000
selFunMax *= 3000
volume = area * (zmax**3 - zmin**3) / 3
if selectionFuncFile == None:
nbar = 1.0
elif not os.access(selectionFuncFile, os.F_OK):
print(" Warning, selection function file %s not found, using default of uniform selection." % selectionFuncFile)
nbar = 1.0
else:
selfunc = np.genfromtxt(selectionFuncFile)
selfunc = np.array(selfunc)
selfunc[:,0] = selfunc[:,0]/100.
selfuncUnity = selfunc
selfuncUnity[:,1] = 1.0
selfuncMin = selfunc[0,0]
selfuncMax = selfunc[-1,0]
selfuncDx = selfunc[1,0] - selfunc[0,0]
selfuncN = np.size(selfunc[:,0])
selFunMin = max(selFunMin, selfuncMin)
selFunMax = min(selFunMax, selfuncMax)
def f(z): return selfunc[np.ceil((z-selfuncMin)/selfuncDx), 1]*z**2
def fTotal(z): return selfuncUnity[np.ceil((z-selfuncMin)/selfuncDx), 1]*z**2
zrange = np.linspace(selFunMin, selFunMax)
nbar = scipy.integrate.quad(f, selFunMin, selFunMax)
nbar = nbar[0]
ntotal = scipy.integrate.quad(fTotal, 0.0, max(selfuncUnity[:,0]))
ntotal = ntotal[0]
nbar = ntotal / area / nbar
return (volume, nbar)
# -----------------------------------------------------------------------------
# returns the nside resolution from the given maskfile
def getNside(maskFile):
nside = 1.0
return nside
# -----------------------------------------------------------------------------
# computes the mask from a given datafile and writes it to a file
def figureOutMask(galFile, nside, outMaskFile):
npix = healpy.nside2npix(nside)
mask = np.zeros((npix))
for line in open(galFile):
line = line.split()
RA = np.float(line[3])
Dec = np.float(line[4])
z = np.float(line[5])
phi = np.pi/180.*RA
theta = Dec*np.pi/180.
theta = np.pi/2. - Dec*np.pi/180.
pos = np.zeros((3))
pix = healpy.ang2pix(nside, theta, phi)
mask[pix] = 1.
healpy.write_map(outMaskFile, mask)
return mask
# -----------------------------------------------------------------------------
# figures out which galaxies live on a mask edge, and also writes the edge
# map to an auxillary file
def findEdgeGalaxies(galFile, maskFile):
return