#include <deal.II/base/thread_management.h>
#include <boost/unordered_map.hpp>
#include <boost/unordered_set.hpp>
+#include <deal.II/lac/sparsity_tools.h>
#include <functional>
#include <set>
return internal::gather_colors(partition_coloring);
}
+ /**
+ * GraphColoring::color_sparsity_pattern, a wrapper function for
+ * SparsityTools::color_sparsity_pattern, is an alternate method for
+ * coloring using graph connections represented by SparsityPattern.
+ * For further details, refer to SparsityTools::color_sparsity_pattern.
+ */
+ unsigned int color_sparsity_pattern (const SparsityPattern &sparsity_pattern,
+ std::vector<unsigned int> &color_indices);
+
} // End graph_coloring namespace
DEAL_II_NAMESPACE_CLOSE
* an edge between two nodes. The goal is to assign each node a color index
* such that no two directly connected nodes have the same color.
* The assigned colors are listed in @p color_indices indexed from one and
- * the function returns total number of colors used. Note that this function
- * requires that SparsityPattern be symmetric (and hence square) i.e an
- * undirected graph representation. We do not check for symmetry of the
- * sparsity pattern, since this is an expensive operation, but rather leave
- * this as the responsibility of caller of this function.
+ * the function returns total number of colors used. ZOLTAN coloring
+ * algorithm is run in serial by each processor. Hence all processors have
+ * coloring information of all the nodes. A wrapper function to this
+ * function is available in GraphColoring namespace as well.
*
- * ZOLTAN coloring algorithm is run in serial by each processor. Hence all
- * processors have coloring information of all the nodes.
+ * Note that this function requires that SparsityPattern be symmetric
+ * (and hence square) i.e an undirected graph representation. We do not
+ * check for symmetry of the sparsity pattern, since this is an expensive
+ * operation, but rather leave this as the responsibility of caller of
+ * this function.
*
* @image html color_undirected_graph.png
- * For example, the above image shows 5 nodes numbered from 0 to 4.
- * The connections shown are bidirectional. After coloring, no two connected
- * nodes have the same color.
+ * The usage of the function is illustrated by the image above, showing five
+ * nodes numbered from 0 to 4. The connections shown are bidirectional.
+ * After coloring, it is clear that no two directly connected nodes are
+ * assigned the same color.
*
* If deal.II was not installed with package ZOLTAN, this function will
* generate an error.
function_time.cc
geometry_info.cc
geometric_utilities.cc
+ graph_coloring.cc
index_set.cc
job_identifier.cc
logstream.cc
--- /dev/null
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 1998 - 2015 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// The deal.II library is free software; you can use it, redistribute
+// it, and/or modify it under the terms of the GNU Lesser General
+// Public License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+// The full text of the license can be found in the file LICENSE at
+// the top level of the deal.II distribution.
+//
+// ---------------------------------------------------------------------
+
+#include <deal.II/base/graph_coloring.h>
+
+
+DEAL_II_NAMESPACE_OPEN
+
+namespace GraphColoring
+{
+ unsigned int color_sparsity_pattern (const SparsityPattern &sparsity_pattern,
+ std::vector<unsigned int> &color_indices)
+ {
+ return SparsityTools::color_sparsity_pattern (sparsity_pattern, color_indices);
+ }
+}
+
+DEAL_II_NAMESPACE_CLOSE
color_exp.data());
//Check for error code
- Assert (rc == ZOLTAN_OK , ExcInternalError());
+ Assert (rc == ZOLTAN_OK ,
+ ExcInternalError());
+
+ //Allocate and assign color indices
+ color_indices.resize(num_objects);
+ Assert (color_exp.size() == color_indices.size(),
+ ExcDimensionMismatch (color_exp.size(),color_indices.size()));
- //Allocate and assign color
std::copy (color_exp.begin(), color_exp.end(), color_indices.begin());
unsigned int n_colors = *(std::max_element (color_indices.begin(),
#include "../tests.h"
-#include <deal.II/grid/tria.h>
-#include <deal.II/grid/tria_accessor.h>
-#include <deal.II/grid/tria_iterator.h>
-#include <deal.II/grid/grid_tools.h>
-#include <deal.II/grid/grid_generator.h>
#include <deal.II/lac/sparsity_tools.h>
-#include <deal.II/numerics/data_out.h>
-
-#include <fstream>
-#include <vector>
-
void fill_graph (DynamicSparsityPattern &graph)
{
--- /dev/null
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2004 - 2015 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// The deal.II library is free software; you can use it, redistribute
+// it, and/or modify it under the terms of the GNU Lesser General
+// Public License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+// The full text of the license can be found in the file LICENSE at
+// the top level of the deal.II distribution.
+//
+// ---------------------------------------------------------------------
+
+
+// check wrapper function GraphColoring::color_sparsity_pattern
+
+
+#include "../tests.h"
+#include <deal.II/base/graph_coloring.h>
+
+
+void fill_graph (DynamicSparsityPattern &graph)
+{
+ //Edges in only one direction
+ graph.add(0,1);
+ graph.add(0,2);
+ graph.add(1,2);
+ graph.add(1,4);
+ graph.add(4,3);
+ graph.add(2,4);
+ graph.add(3,2);
+
+ //Edges in opposite direction
+ graph.add(1,0);
+ graph.add(2,0);
+ graph.add(2,1);
+ graph.add(4,1);
+ graph.add(3,4);
+ graph.add(4,2);
+ graph.add(2,3);
+}
+
+
+int main (int argc, char **argv)
+{
+ //Initialize MPI and Zoltan
+ Utilities::MPI::MPI_InitFinalize mpi_initialization (argc, argv);
+ MPILogInitAll all;
+
+ //Number of nodes
+ unsigned int num_indices = 5;
+
+ //Create temporary object to hold graph connection info.
+ DynamicSparsityPattern dynamic_sparse_graph;
+ dynamic_sparse_graph.reinit(num_indices,num_indices);
+
+ //fill dynamic sparsity pattern
+ fill_graph(dynamic_sparse_graph);
+
+ //Create sparity pattern to hold graph connection info.
+ SparsityPattern sp_graph;
+ sp_graph.copy_from(dynamic_sparse_graph);
+
+ Assert( num_indices == sp_graph.n_rows() , ExcInternalError() );
+
+ std::vector<unsigned int> color_indices;
+ unsigned int num_colors;
+
+ color_indices.resize(num_indices);
+ num_colors = GraphColoring::color_sparsity_pattern (sp_graph, color_indices);
+
+ //color
+ deallog << "Coloring" << std::endl;
+ deallog << "Number of colors used: " << num_colors << std::endl;
+ for (unsigned int i=0; i<num_indices; i++)
+ {
+ deallog << i << " " << color_indices[i] << std::endl;
+ }
+}
--- /dev/null
+
+DEAL:0::Coloring
+DEAL:0::Number of colors used: 4
+DEAL:0::0 1
+DEAL:0::1 2
+DEAL:0::2 3
+DEAL:0::3 1
+DEAL:0::4 4
projects / dealii.git / commitdiff