Switch back to the same matrix terms in the Stokes preconditioner we

have been using in step-31. The formula yields the same terms up to
roundoff anyway.

git-svn-id: https://svn.dealii.org/trunk@24528 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/examples/step-32/step-32.cc b/deal.II/examples/step-32/step-32.cc
index ccd6bf525250ec11c0d62b21e39c0ec200258970..6d5fc9cbcabe50da42919dbf4553b3b61802c820 100644 (file)
--- a/deal.II/examples/step-32/step-32.cc
+++ b/deal.II/examples/step-32/step-32.cc
@@ -437,10 +437,10 @@ namespace Step32
          StokesPreconditioner (const StokesPreconditioner &data);
 
 
-         FEValues<dim>                        stokes_fe_values;
+         FEValues<dim>               stokes_fe_values;
 
-         std::vector<SymmetricTensor<2,dim> > grads_phi_u;
-         std::vector<double>                  phi_p;
+         std::vector<Tensor<2,dim> > grad_phi_u;
+         std::vector<double>         phi_p;
       };
 
       template <int dim>
@@ -452,7 +452,7 @@ namespace Step32
                      :
                      stokes_fe_values (mapping, stokes_fe, stokes_quadrature,
                                        update_flags),
-                     grads_phi_u (stokes_fe.dofs_per_cell),
+                     grad_phi_u (stokes_fe.dofs_per_cell),
                      phi_p (stokes_fe.dofs_per_cell)
       {}
 
@@ -466,7 +466,7 @@ namespace Step32
                                        scratch.stokes_fe_values.get_fe(),
                                        scratch.stokes_fe_values.get_quadrature(),
                                        scratch.stokes_fe_values.get_update_flags()),
-                     grads_phi_u (scratch.grads_phi_u),
+                     grad_phi_u (scratch.grad_phi_u),
                      phi_p (scratch.phi_p)
       {}
 
@@ -2682,25 +2682,21 @@ namespace Step32
       {
        for (unsigned int k=0; k<dofs_per_cell; ++k)
          {
-           scratch.grads_phi_u[k] = scratch.stokes_fe_values[velocities].symmetric_gradient(k,q);
-           scratch.phi_p[k]       = scratch.stokes_fe_values[pressure].value (k, q);
+           scratch.grad_phi_u[k] = scratch.stokes_fe_values[velocities].gradient(k,q);
+           scratch.phi_p[k]      = scratch.stokes_fe_values[pressure].value (k, q);
          }
 
        for (unsigned int i=0; i<dofs_per_cell; ++i)
          for (unsigned int j=0; j<dofs_per_cell; ++j)
-           if (stokes_fe.system_to_component_index(i).first
-               ==
-               stokes_fe.system_to_component_index(j).first)
-//@todo figure this out...
-             data.local_matrix(i,j) += (EquationData::eta *
-                                        (scratch.grads_phi_u[i] *
-                                         scratch.grads_phi_u[j])
-                                        +
-                                        (1./EquationData::eta) *
-                                        EquationData::pressure_scaling *
-                                        EquationData::pressure_scaling *
-                                        (scratch.phi_p[i] * scratch.phi_p[j]))
-                                       * scratch.stokes_fe_values.JxW(q);
+           data.local_matrix(i,j) += (EquationData::eta *
+                                      scalar_product (scratch.grad_phi_u[i],
+                                                      scratch.grad_phi_u[j])
+                                      +
+                                      (1./EquationData::eta) *
+                                      EquationData::pressure_scaling *
+                                      EquationData::pressure_scaling *
+                                      (scratch.phi_p[i] * scratch.phi_p[j]))
+                                     * scratch.stokes_fe_values.JxW(q);
       }
   }