from __future__ import division
import numpy as np

c          = 3*10**5          #km/s
h          = 6.626*10**-34    #J s
kb         = 1.3805*10**-23   #J/K

ergps2Lsun = 1/(3.826*10**33) #ergs/s to L_sun
Jps2Lsun   = 1/(3.826*10**26) #J/s to L_sun
ergs2Jy    = 10**23           #erg/s/cm^2/Hz to Jy
eV2J       = 1.60218E-19
J2erg      = 10**7
Mpc2cm     = 3.086E24
Mpc2km     = 3.086E19
kpc2cm     = 3.086E21
pc2cm      = 3.086E18
Lsun2Jps   = 3.826*10**26
Gyr2s      = 10**9*365*24*3600
Msun2kg    = 1.989E30
mH2kg      = 1.6735575*10**-27 #H mass in unit of kg
