Merge pull request #96 from brittonsmith/vu

add proper and comoving velocity units to python scripts
grackle-project · Feb 17, 2022 · 8feca8e · 8feca8e
2 parents a4e05a4 + 8b42f96
commit 8feca8e
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Showing 3 changed files with 30 additions and 7 deletions.
diff --git a/src/python/examples/cooling_cell.py b/src/python/examples/cooling_cell.py
@@ -61,9 +61,16 @@
     my_chemistry.density_units = mass_hydrogen_cgs # rho = 1.0 is 1.67e-24 g
     my_chemistry.length_units = cm_per_mpc         # 1 Mpc in cm
     my_chemistry.time_units = sec_per_Myr          # 1 Myr in s
-    my_chemistry.velocity_units = my_chemistry.a_units * \
-        (my_chemistry.length_units / my_chemistry.a_value) / \
-        my_chemistry.time_units
+
+    if my_chemistry.comoving_coordinates:
+        # velocity units for comoving coordinates
+        my_chemistry.velocity_units = my_chemistry.a_units * \
+          (my_chemistry.length_units / my_chemistry.a_value) / \
+          my_chemistry.time_units
+    else:
+        # velocity units for proper coordinates
+        my_chemistry.velocity_units = my_chemistry.length_units / \
+          my_chemistry.time_units
 
     rval = my_chemistry.initialize()
 

diff --git a/src/python/examples/cooling_rate.py b/src/python/examples/cooling_rate.py
@@ -56,9 +56,16 @@
     my_chemistry.density_units = mass_hydrogen_cgs # rho = 1.0 is 1.67e-24 g
     my_chemistry.length_units = cm_per_mpc         # 1 Mpc in cm
     my_chemistry.time_units = sec_per_Myr          # 1 Gyr in s
-    my_chemistry.velocity_units = my_chemistry.a_units * \
-        (my_chemistry.length_units / my_chemistry.a_value) / \
-        my_chemistry.time_units
+
+    if my_chemistry.comoving_coordinates:
+        # velocity units for comoving coordinates
+        my_chemistry.velocity_units = my_chemistry.a_units * \
+          (my_chemistry.length_units / my_chemistry.a_value) / \
+          my_chemistry.time_units
+    else:
+        # velocity units for proper coordinates
+        my_chemistry.velocity_units = my_chemistry.length_units / \
+          my_chemistry.time_units
 
     # Call convenience function for setting up a fluid container.
     # This container holds the solver parameters, units, and fields.

diff --git a/src/python/examples/freefall.py b/src/python/examples/freefall.py
@@ -66,7 +66,16 @@
     my_chemistry.density_units  = mass_hydrogen_cgs # rho = 1.0 is 1.67e-24 g
     my_chemistry.length_units   = cm_per_mpc        # 1 Mpc in cm
     my_chemistry.time_units     = sec_per_Myr       # 1 Myr in s
-    my_chemistry.velocity_units = my_chemistry.length_units / my_chemistry.time_units
+
+    if my_chemistry.comoving_coordinates:
+        # velocity units for comoving coordinates
+        my_chemistry.velocity_units = my_chemistry.a_units * \
+          (my_chemistry.length_units / my_chemistry.a_value) / \
+          my_chemistry.time_units
+    else:
+        # velocity units for proper coordinates
+        my_chemistry.velocity_units = my_chemistry.length_units / \
+          my_chemistry.time_units
 
     # set initial density and temperature
     initial_temperature = 50000. # start the gas at this temperature