From: kanschat <kanschat@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Fri, 23 Mar 2012 22:04:50 +0000 (+0000)
Subject: compute the norm of the divergence
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e4258b34e4b8f8e5d4108471ef8210af3c2e7a7d;p=dealii-svn.git

compute the norm of the divergence

git-svn-id: https://svn.dealii.org/trunk@25323 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/include/deal.II/integrators/divergence.h b/deal.II/include/deal.II/integrators/divergence.h
index e8f7e95303..9ae0c14120 100644
--- a/deal.II/include/deal.II/integrators/divergence.h
+++ b/deal.II/include/deal.II/integrators/divergence.h
@@ -366,6 +366,27 @@ namespace LocalIntegrators
 		}
 	}
     }
+
+    template <int dim>
+    double norm(const FEValuesBase<dim>& fe,
+		const VectorSlice<const std::vector<std::vector<Tensor<1,dim> > > >& Du)
+    {
+      unsigned int fecomp = fe.get_fe().n_components();
+      
+      AssertDimension(fecomp, dim);
+      AssertVectorVectorDimension (Du, dim, fe.n_quadrature_points);
+
+      double result = 0;
+      for (unsigned k=0;k<fe.n_quadrature_points;++k)
+	{
+	  double div = Du[0][k][0];
+	  for (unsigned int d=1;d<dim;++d)
+	    div += Du[d][k][d];
+	  result += div+div;
+	}
+      return result;
+    }
+
   }
 }