diff options
| -rw-r--r-- | acispy/cosmo.py | 3 | ||||
| -rwxr-xr-x | scripts/cosmo_calc.py | 91 |
2 files changed, 93 insertions, 1 deletions
diff --git a/acispy/cosmo.py b/acispy/cosmo.py index c3d6096..62b9191 100644 --- a/acispy/cosmo.py +++ b/acispy/cosmo.py @@ -57,7 +57,7 @@ class Calculator: 1 ACIS pixel (i.e., 0.492 arcsec) at the *angular diameter distance* of z. """ - return self.kpc_per_pix * au.kpc.to(au.cm) + return self.kpc_per_pix(z) * au.kpc.to(au.cm) def norm_apec(self, z): """ @@ -65,6 +65,7 @@ class Calculator: EM = 1 (i.e., n_e = n_H = 1 cm^-3, and V = 1 cm^3) norm = 1e-14 / (4*pi* (D_A * (1+z))^2) * int(n_e * n_H) dV + unit: [cm^-5] This value will be used to calculate the cooling function values. diff --git a/scripts/cosmo_calc.py b/scripts/cosmo_calc.py new file mode 100755 index 0000000..7381da0 --- /dev/null +++ b/scripts/cosmo_calc.py @@ -0,0 +1,91 @@ +#!/usr/bin/env python3 +# +# Copyright (c) 2017 Weitian LI <liweitianux@live.com> +# MIT license + +""" +Cosmology calculator with support of Chandra ACIS-specific quantities. +""" + +import argparse + +from context import acispy +from acispy.cosmo import Calculator + + +def main(): + parser = argparse.ArgumentParser( + description="Cosmology calculator with Chandra-specific quantities") + parser.add_argument("-H", "--hubble", dest="H0", + type=float, default=71.0, + help="Present-day Hubble parameter " + + "(default: 71 km/s/Mpc)") + parser.add_argument("-M", "--omega-m", dest="Om0", + type=float, default=0.27, + help="Present-day matter density (default: 0.27") + parser.add_argument("-b", "--brief", dest="brief", action="store_true", + help="be brief") + parser.add_argument("-U", "--unit", dest="unit", + help="unit for output quantity if supported") + group = parser.add_mutually_exclusive_group(required=True) + group.add_argument("-L", "--luminosity-distance", + dest="luminosity_distance", + action="store_true", + help="calculate the luminosity distance (DL)") + group.add_argument("-A", "--angular-diameter-distance", + dest="angular_diameter_distance", + action="store_true", + help="calculate the angular diameter distance (DA)") + group.add_argument("--kpc-per-arcsec", dest="kpc_per_arcsec", + action="store_true", + help="calculate the transversal length [kpc] " + + "w.r.t. 1 arcsec at DA(z)") + group.add_argument("--kpc-per-pix", dest="kpc_per_pix", + action="store_true", + help="calculate the transversal length [kpc] " + + "w.r.t. 1 ACIS pixel (0.492 arcsec) at DA(z)") + group.add_argument("--cm-per-pix", dest="cm_per_pix", + action="store_true", + help="calculate the transversal length [cm] " + + "w.r.t. 1 ACIS pixel (0.492 arcsec) at DA(z)") + group.add_argument("--norm-apec", dest="norm_apec", + action="store_true", + help="calculate the normalization factor " + + "of the XSPEC APEC model assuming EM=1") + parser.add_argument("z", type=float, help="redshift") + args = parser.parse_args() + + cosmocalc = Calculator(H0=args.H0, Om0=args.Om0) + + if args.luminosity_distance: + kwargs = {"z": args.z} + kwargs["unit"] = args.unit if args.unit else "Mpc" + label = "Luminosity distance [%s]" % kwargs["unit"] + value = cosmocalc.luminosity_distance(**kwargs) + elif args.angular_diameter_distance: + kwargs = {"z": args.z} + kwargs["unit"] = args.unit if args.unit else "Mpc" + label = "Angular diameter distance [%s]" % kwargs["unit"] + value = cosmocalc.angular_diameter_distance(**kwargs) + elif args.kpc_per_arcsec: + label = "kpc/arcsec (DA)" + value = cosmocalc.kpc_per_arcsec(args.z) + elif args.kpc_per_pix: + label = "kpc/pix (DA)" + value = cosmocalc.kpc_per_pix(args.z) + elif args.cm_per_pix: + label = "cm/pix (DA)" + value = cosmocalc.cm_per_pix(args.z) + elif args.norm_apec: + label = "norm (APEC) [cm^-5]" + value = cosmocalc.norm_apec(args.z) + else: + raise ValueError("no quantity to calculate") + + if not args.brief: + print(label + ": ", end="", flush=True) + print(value) + + +if __name__ == "__main__": + main() |