Update swm_cartesian.py

fixing the read_val array orders

Author: supreethms1809

swm_python/swm_cartesian.py

@@ -461,7 +461,7 @@ def copy_var(
         vval = np.zeros((M_LEN, N_LEN))
         pval = np.zeros((M_LEN, N_LEN))
 
-        uref, vref, pref = read_arrays(v_val_f, u_val_f, p_val_f)
+        uref, vref, pref = read_arrays(u_val_f, v_val_f, p_val_f)
         uval = uref-unew[:,:,0]
         vval = vref-vnew[:,:,0]
         pval = pref-pnew[:,:,0]
@@ -612,7 +612,7 @@ def calc_h_program(
         vval = np.zeros((M_LEN, N_LEN))
         pval = np.zeros((M_LEN, N_LEN))
 
-        uref, vref, pref = read_arrays(v_val_f, u_val_f, p_val_f)
+        uref, vref, pref = read_arrays(u_val_f, v_val_f, p_val_f)
         uval = uref-unew
         vval = vref-vnew
         pval = pref-pnew