def mean_field_rho_mean(snapshot, field, ret_rho_mean=False):
'''
Computes mean (volume and mass weighted) temperature at the mean density
'''
import numpy as np
from seren3.cosmology import rho_mean_z
from seren3.utils import approx_equal
cosmo = snapshot.cosmo
rho_mean = snapshot.array(rho_mean_z(cosmo["omega_b_0"], **cosmo),
"kg m**-3")
field_list = []
mass = []
units = None
for dset in snapshot.g[["rho", "mass", field]]:
ix = np.where(approx_equal(rho_mean, dset['rho'], tol=None, rel=1e-5))
if (len(ix[0]) > 0):
if (units is None):
units = str(dset[field].units)
field_list.extend(dset[field][ix])
mass.extend(dset["mass"][ix])
mass = np.array(mass)
field_list = np.array(field_list)
mw = snapshot.array(np.sum(field_list * mass) / mass.sum(), units)
if ret_rho_mean:
return mw, rho_mean
return mw
def __init__(self, **cosmo):
self.gammaF = 4 * math.pi / 3
self.cosmo = cosmo
omega0 = cosmo["omega_M_0"]
rho_bar = SimArray(cosmology.rho_mean_z(omega0, **cosmo), "kg m**-3")
self.rho_bar = rho_bar.in_units("Msol Mpc^-3") # h^2 a^-3")
self.rho_bar *= cosmo['h']**2 * cosmo['aexp']**3
self.rho_bar.units = "Msol Mpc^-3 h^2 a^-3"
def dm_delta(context, dset, **kwargs):
from seren3.cosmology import rho_mean_z
rhoc = dm_rho(context, dset, **kwargs)
cosmo = context.cosmo
omega0 = cosmo['omega_M_0'] - cosmo['omega_b_0']
rho_mean = rho_mean_z(omega0, **cosmo)
delta = (rhoc - rho_mean) / rho_mean
return delta
def deltab(sim):
from seren3 import cosmology
from seren3.array import SimArray
omega_b_0 = 0.045
cosmo = sim.properties.copy()
cosmo["z"] = (1. / cosmo['a']) - 1.
rho_mean = SimArray(cosmology.rho_mean_z(omega_b_0, **cosmo), "kg m**-3")
rho = sim.g["rho"].in_units("kg m**-3")
db = (rho - rho_mean) / rho_mean
return db
def deltac(self):
'''
Returns CDM overdensity field
'''
from seren3.cosmology import rho_mean_z
cosmo = self.base.cosmo
omega0 = cosmo['omega_M_0'] - cosmo['omega_b_0']
rho_mean = rho_mean_z(omega0, **cosmo)
rhoc = self.rhoc
delta = (rhoc - rho_mean) / rho_mean
return delta
def deltac_cic(context, rhoc=None):
'''
Returns CDM overdensity field
'''
from seren3.cosmology import rho_mean_z
cosmo = context.cosmo # get the cosmological context - this is a dictionary
omega0 = cosmo['omega_M_0'] - cosmo['omega_b_0'] # CDM density param.
rho_mean = rho_mean_z(omega0, **cosmo) # mean (CDM) density at this redshift
if (rhoc is None):
rhoc = rhoc_cic(context)
delta = (rhoc - rho_mean) / rho_mean # the CDM overdensity
return delta
def rho_mean(self, species='baryon'):
'''
Mean density at current redshift of baryons or cdm
'''
from seren3.cosmology import rho_mean_z
cosmo = self.base.cosmo
omega_0 = 0.
if (species == 'b') or (species == 'baryon'):
omega_0 = cosmo['omega_b_0']
elif (species == 'c') or (species == 'cdm'):
omega_0 = cosmo['omega_M_0'] - cosmo['omega_b_0']
else:
raise Exception("Unknown species %s" % species)
rho_mean = rho_mean_z(omega_0, **cosmo)
return SimArray(rho_mean, "kg m**-3")
def rho_mean(self, species):
'''
Compute mean density of given species at current redshift
'''
from seren3 import cosmology
cosmo = self.header.cosmo
cosmo["z"] = int(cosmo["z"])
omega0 = 0.
if ('b' == species) or ('baryons' == species):
omega0 = cosmo['omega_b_0']
elif ('c' == species) or ('cdm' == species):
omega0 = cosmo['omega_M_0'] - cosmo['omega_b_0']
elif ('tot' == species) or ('total' == species):
omega0 = cosmo['omega_M_0']
else:
raise Exception("Unknown species: %s" % species)
rho_mean = SimArray(cosmology.rho_mean_z(omega0, **cosmo), "kg m**-3")
return rho_mean