From: kanschat <kanschat@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Tue, 4 Oct 2011 02:23:51 +0000 (+0000)
Subject: eliminate interior boundaries
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3cd2019e1eb1f9cf704e8ed99777b8931d908586;p=dealii-svn.git

eliminate interior boundaries

git-svn-id: https://svn.dealii.org/trunk@24520 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/include/deal.II/dofs/dof_tools.h b/deal.II/include/deal.II/dofs/dof_tools.h
index cd27f3b21d..e387e694c4 100644
--- a/deal.II/include/deal.II/dofs/dof_tools.h
+++ b/deal.II/include/deal.II/dofs/dof_tools.h
@@ -1464,6 +1464,16 @@ namespace DoFTools
 				   // @}
 				   /**
 				    * @name Dof indices for patches
+				    *
+				    * Create structures containing a
+				    * large set of degrees of freedom
+				    * for small patches of cells. The
+				    * resulting objects can be used in
+				    * RelaxationBlockSOR and related
+				    * classes to implement Schwarz
+				    * preconditioners and smoothers,
+				    * where the subdomains consist of
+				    * small numbers of cells only.
 				    */
 				   //@{
 				   /**
@@ -1486,13 +1496,61 @@ namespace DoFTools
 				     * freedom associated to the
 				     * corresponding cells
 				     * corresponding to a vertex.
+				     *
+				     * The function has some boolean
+				     * arguments (lsited below)
+				     * controlling details of the
+				     * generated patches. The default
+				     * settings are those for
+				     * Arnold-Falk-Winther type
+				     * smoothers for divergence and
+				     * curl conforming finite elements
+				     * with essential boundary
+				     * conditions. Other applications
+				     * are possible, in particular
+				     * changing
+				     * <tt>boundary_patches</tt> for
+				     * non-essential boundary conditions.
+				     *
+				     * @arg <tt>block_list</tt>: the
+				     * SparsityPattern into which the
+				     * patches will be stored.
+				     * @arg <tt>dof_handler</tt>: The
+				     * multilevel dof handler
+				     * providing the topology operated
+				     * on.
+				     * @arg
+				     * <tt>interior_dofs_only</tt>:
+				     * for each patch of cells around
+				     * a vertex, collect only the
+				     * interior degrees of freedom of
+				     * the patch and disregard those
+				     * on the boundary of the
+				     * patch. This is for instance the
+				     * setting for smoothers of
+				     * Arnold-Falk-Winther type.
+				     * @arg <tt>boundary_patches</tt>:
+				     * include patches around vertices
+				     * at the boundary of the
+				     * domain. If not, only patches
+				     * around interior vertices will
+				     * be generated.
+				     * @arg
+				     * <tt>level_boundary_patches</tt>:
+				     * same for refinement edges
+				     * towards coarser cells.
+				     * @arg
+				     * <tt>single_cell_patches</tt>:
+				     * if not true, patches containing
+				     * a single cell are eliminated.
 				     */
    template <class DH>
    void make_vertex_patches(SparsityPattern& block_list,
 			    const DH& dof_handler,
 			    const unsigned int level,
 			    const bool interior_dofs_only,
-			    const bool boundary_patches = true,
+			    const bool boundary_patches = false,
+			    const bool level_boundary_patches = false,
 			    const bool single_cell_patches = false);
   
 				   //@}
diff --git a/deal.II/source/dofs/dof_tools.cc b/deal.II/source/dofs/dof_tools.cc
index 2d4eb64933..c78b30e51d 100644
--- a/deal.II/source/dofs/dof_tools.cc
+++ b/deal.II/source/dofs/dof_tools.cc
@@ -5913,8 +5913,15 @@ namespace DoFTools
 	  vertex_dof_count[vg] += cell->get_fe().dofs_per_cell;
 	  ++vertex_cell_count[vg];
 	  for (unsigned int d=0;d<DH::dimension;++d)
-	    if (cell->at_boundary(GeometryInfo<DH::dimension>::vertex_to_face[v][d]))
-	      vertex_boundary[vg] = true;
+	    {
+	      const unsigned int face = GeometryInfo<DH::dimension>::vertex_to_face[v][d];
+	      if (cell->at_boundary(face))
+		vertex_boundary[vg] = true;
+	      else
+		if ((!level_boundary_patches)
+		    && (cell->neighbor(face)->level() != (int) level))
+		  vertex_boundary[vg] = true;
+	    }
 	}
 				     // From now on, onlly vertices
 				     // with positive dof count are