PR #518: from firedrakeproject/1D_courant_logging

Allow logging of Courant numbers for a scalar velocity field
firedrakeproject · Jul 23, 2024 · c0e65f3 · c0e65f3
2 parents 9930f6e + c360407
commit c0e65f3
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Showing 2 changed files with 7 additions and 3 deletions.
diff --git a/examples/shallow_water/shallow_water_1d.py b/examples/shallow_water/shallow_water_1d.py
@@ -24,8 +24,7 @@
                                 diffusion_options=diffusion_options)
 
 output = OutputParameters(dirname="1dsw_%s" % str(epsilon),
-                          dumpfreq=50,
-                          log_courant=False)
+                          dumpfreq=50)
 io = IO(domain, output)
 
 transport_methods = [DGUpwind(eqns, "u"), DGUpwind(eqns, "v"),

diff --git a/gusto/diagnostics/diagnostics.py b/gusto/diagnostics/diagnostics.py
@@ -322,7 +322,12 @@ def setup(self, domain, state_fields):
 
         # Set up form for DG flux
         n = FacetNormal(domain.mesh)
-        un = 0.5*(inner(-u_expr, n) + abs(inner(-u_expr, n)))
+
+        # Check if the velocity is a vector or scalar field
+        if u.ufl_shape == ():
+            un = 0.5*(-u_expr * n[0] + abs(-u_expr * n[0]))
+        else:
+            un = 0.5*(inner(-u_expr, n) + abs(inner(-u_expr, n)))
         self.cell_flux_form = 2*avg(un*test)*dS_calc + un*test*ds_calc
 
         # Final Courant number expression