diff options
| -rw-r--r-- | fg21sim/utils/cosmology.py | 49 |
1 files changed, 38 insertions, 11 deletions
diff --git a/fg21sim/utils/cosmology.py b/fg21sim/utils/cosmology.py index c5a5119..3a4d5fd 100644 --- a/fg21sim/utils/cosmology.py +++ b/fg21sim/utils/cosmology.py @@ -5,6 +5,8 @@ Flat ΛCDM cosmological model. """ +import logging + import numpy as np from scipy import integrate from astropy.cosmology import FlatLambdaCDM @@ -13,6 +15,9 @@ from ..configs import configs from .units import (UnitConversions as AUC, Constants as AC) +logger = logging.getLogger(__name__) + + class Cosmology: """ Flat ΛCDM cosmological model. @@ -21,6 +26,7 @@ class Cosmology: ---------- H0 : float Hubble parameter at present day (z=0) + Unit: [km/s/Mpc] Om0 : float Density parameter of (dark and baryon) matter at present day Ob0 : float @@ -30,6 +36,13 @@ class Cosmology: sigma8 : float Present-day rms density fluctuation on a scale of 8 h^-1 Mpc. + Internal attributes + ------------------- + _cosmo : `~astropy.cosmology.Cosmology` + Astropy cosmology instance to help calculations. + _growth_factor0 : float + Present day (z=0) growth factor + References ---------- [1] https://astro.uni-bonn.de/~pavel/WIKIPEDIA/Lambda-CDM_model.html @@ -38,16 +51,30 @@ class Cosmology: http://adsabs.harvard.edu/abs/2002ApJ...577..579R Sec.(2) """ - def __init__(self, H0=configs.getn("cosmology/H0"), - Om0=configs.getn("cosmology/OmegaM0"), - Ob0=configs.getn("cosmology/Omegab0"), - sigma8=configs.getn("cosmology/sigma8")): - self.H0 = H0 # [km/s/Mpc] - self.Om0 = Om0 - self.Ob0 = Ob0 - self.Ode0 = 1.0 - Om0 - self.sigma8 = sigma8 - self._cosmo = FlatLambdaCDM(H0=H0, Om0=Om0, Ob0=Ob0) + # Present day (z=0) growth factor + _growth_factor0 = None + + def __init__(self, + H0=configs.cosmology["H0"], + Om0=configs.cosmology["OmegaM0"], + Ob0=configs.cosmology["Omegab0"], + sigma8=configs.cosmology["sigma8"]): + self.setup(H0=H0, Om0=Om0, Ob0=Ob0, sigma8=sigma8) + + def setup(self, **kwargs): + """ + Setup/update the parameters of the cosmology model. + """ + for key, value in kwargs: + if key in ["H0", "Om0", "Ob0", "sigma8"]: + setattr(self, key, value) + else: + raise ValueError("unknown parameter: %s" % key) + + self.Ode0 = 1.0 - self.Om0 + self._cosmo = FlatLambdaCDM(H0=self.H0, Om0=self.Om0, Ob0=self.Ob0) + self._growth_factor0 = None + logger.info("Setup cosmology with: {0}".format(kwargs)) @property def h(self): @@ -228,6 +255,6 @@ class Cosmology: """ Present-day (z=0) growth factor. """ - if not hasattr(self, "_growth_factor0"): + if self._growth_factor0 is None: self._growth_factor0 = self.growth_factor(0) return self._growth_factor0 |