imports cosmology from astropy

instead of Planck18 directly

Author: sambit-giri

src/tools21cm/line_intensity.py

@@ -2,7 +2,7 @@
 from glob import glob
 import astropy
 from astropy import constants, units
-from astropy.cosmology import Planck18
+from astropy import cosmology
 
 from .nbody_file import halo_list_to_grid
 
@@ -39,7 +39,7 @@ def M_HI_on_grid(z, mass, pos_xyz, box_dim, n_grid, cosmo=None,
     assert recipe.lower() in ['padmanabhan2017']
     if cosmo is None:
         print('Assuming Planck18 cosmology.')
-        cosmo = Planck18
+        cosmo = cosmology.Planck18
     Ob = cosmo.Ob0
     Om = cosmo.Om0 
     hlittle = cosmo.h
@@ -109,7 +109,7 @@ def L_CII_on_grid(z, mass, pos_xyz, box_dim, n_grid, SFR=None, cosmo=None,
     assert recipe.lower() in ['silva2015m1', 'silva2015m2', 'silva2015m3', 'silva2015m4']
     if cosmo is None:
         print('Assuming Planck18 cosmology.')
-        cosmo = Planck18
+        cosmo = cosmology.Planck18
     Ob = cosmo.Ob0
     Om = cosmo.Om0 
     hlittle = cosmo.h

src/tools21cm/temperature.py

@@ -8,7 +8,7 @@
 from .helper_functions import print_msg, read_cbin, \
 	get_data_and_type, determine_redshift_from_filename
 from astropy import constants, units
-from astropy.cosmology import Planck18
+from astropy import cosmology
 
 def calc_dt_halo(mhalo, box_dim, z, Y_p=0.249, cosmo=None):
 	'''
@@ -28,7 +28,7 @@ def calc_dt_halo(mhalo, box_dim, z, Y_p=0.249, cosmo=None):
 	'''
 	if cosmo is None:
 		print('Assuming Planck18 cosmology.')
-		cosmo = Planck18
+		cosmo = cosmology.Planck18
 
 	if isinstance(mhalo, units.quantity.Quantity):
 		mhalo = mhalo.to('Msun')