Chris@16: // Copyright 2004 The Trustees of Indiana University.
Chris@16: 
Chris@16: // Distributed under the Boost Software License, Version 1.0.
Chris@16: // (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: //  Authors: Jeremiah Willcock
Chris@16: //           Douglas Gregor
Chris@16: //           Andrew Lumsdaine
Chris@16: #ifndef BOOST_GRAPH_GURSOY_ATUN_LAYOUT_HPP
Chris@16: #define BOOST_GRAPH_GURSOY_ATUN_LAYOUT_HPP
Chris@16: 
Chris@16: // Gursoy-Atun graph layout, based on:
Chris@16: // "Neighbourhood Preserving Load Balancing: A Self-Organizing Approach"
Chris@16: // in EuroPar 2000, p. 234 of LNCS 1900
Chris@16: // http://springerlink.metapress.com/link.asp?id=pcu07ew5rhexp9yt
Chris@16: 
Chris@16: #include <boost/config/no_tr1/cmath.hpp>
Chris@16: #include <boost/throw_exception.hpp>
Chris@16: #include <boost/assert.hpp>
Chris@16: #include <vector>
Chris@16: #include <exception>
Chris@16: #include <algorithm>
Chris@16: 
Chris@16: #include <boost/graph/visitors.hpp>
Chris@16: #include <boost/graph/properties.hpp>
Chris@16: #include <boost/random/uniform_01.hpp>
Chris@16: #include <boost/random/linear_congruential.hpp>
Chris@16: #include <boost/shared_ptr.hpp>
Chris@16: #include <boost/graph/breadth_first_search.hpp>
Chris@16: #include <boost/graph/dijkstra_shortest_paths.hpp>
Chris@16: #include <boost/graph/named_function_params.hpp>
Chris@16: #include <boost/graph/topology.hpp>
Chris@16: 
Chris@16: namespace boost { 
Chris@16: 
Chris@16: namespace detail {
Chris@16: 
Chris@16: struct over_distance_limit : public std::exception {};
Chris@16: 
Chris@16: template <typename PositionMap, typename NodeDistanceMap,  typename Topology,
Chris@16:           typename Graph>
Chris@16: struct update_position_visitor {
Chris@16:   typedef typename Topology::point_type Point;
Chris@16:   PositionMap position_map;
Chris@16:   NodeDistanceMap node_distance;
Chris@16:   const Topology& space;
Chris@16:   Point input_vector;
Chris@16:   double distance_limit;
Chris@16:   double learning_constant;
Chris@16:   double falloff_ratio;
Chris@16: 
Chris@16:   typedef boost::on_examine_vertex event_filter;
Chris@16: 
Chris@16:   typedef typename graph_traits<Graph>::vertex_descriptor
Chris@16:     vertex_descriptor;
Chris@16: 
Chris@16:   update_position_visitor(PositionMap position_map,
Chris@16:                           NodeDistanceMap node_distance,
Chris@16:                           const Topology& space,
Chris@16:                           const Point& input_vector,
Chris@16:                           double distance_limit,
Chris@16:                           double learning_constant,
Chris@16:                           double falloff_ratio):
Chris@16:     position_map(position_map), node_distance(node_distance), 
Chris@16:     space(space),
Chris@16:     input_vector(input_vector), distance_limit(distance_limit),
Chris@16:     learning_constant(learning_constant), falloff_ratio(falloff_ratio) {}
Chris@16: 
Chris@16:   void operator()(vertex_descriptor v, const Graph&) const 
Chris@16:   {
Chris@16: #ifndef BOOST_NO_STDC_NAMESPACE
Chris@16:     using std::pow;
Chris@16: #endif
Chris@16: 
Chris@16:     if (get(node_distance, v) > distance_limit)
Chris@16:       BOOST_THROW_EXCEPTION(over_distance_limit());
Chris@16:     Point old_position = get(position_map, v);
Chris@16:     double distance = get(node_distance, v);
Chris@16:     double fraction = 
Chris@16:       learning_constant * pow(falloff_ratio, distance * distance);
Chris@16:     put(position_map, v,
Chris@16:         space.move_position_toward(old_position, fraction, input_vector));
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: template<typename EdgeWeightMap>
Chris@16: struct gursoy_shortest
Chris@16: {
Chris@16:   template<typename Graph, typename NodeDistanceMap, typename UpdatePosition>
Chris@16:   static inline void 
Chris@16:   run(const Graph& g, typename graph_traits<Graph>::vertex_descriptor s,
Chris@16:       NodeDistanceMap node_distance,  UpdatePosition& update_position,
Chris@16:       EdgeWeightMap weight)
Chris@16:   {
Chris@16:     boost::dijkstra_shortest_paths(g, s, weight_map(weight).
Chris@16:       visitor(boost::make_dijkstra_visitor(std::make_pair(
Chris@16:        boost::record_distances(node_distance, boost::on_edge_relaxed()),
Chris@16:         update_position))));
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: template<>
Chris@16: struct gursoy_shortest<dummy_property_map>
Chris@16: {
Chris@16:   template<typename Graph, typename NodeDistanceMap, typename UpdatePosition>
Chris@16:   static inline void 
Chris@16:   run(const Graph& g, typename graph_traits<Graph>::vertex_descriptor s,
Chris@16:       NodeDistanceMap node_distance,  UpdatePosition& update_position,
Chris@16:       dummy_property_map)
Chris@16:   {
Chris@16:     boost::breadth_first_search(g, s,
Chris@16:       visitor(boost::make_bfs_visitor(std::make_pair(
Chris@16:         boost::record_distances(node_distance, boost::on_tree_edge()),
Chris@16:         update_position))));
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: } // namespace detail
Chris@16: 
Chris@16: template <typename VertexListAndIncidenceGraph,  typename Topology,
Chris@16:           typename PositionMap, typename Diameter, typename VertexIndexMap, 
Chris@16:           typename EdgeWeightMap>
Chris@16: void 
Chris@16: gursoy_atun_step
Chris@16:   (const VertexListAndIncidenceGraph& graph,  
Chris@16:    const Topology& space,
Chris@16:    PositionMap position,
Chris@16:    Diameter diameter,
Chris@16:    double learning_constant,
Chris@16:    VertexIndexMap vertex_index_map,
Chris@16:    EdgeWeightMap weight)
Chris@16: {
Chris@16: #ifndef BOOST_NO_STDC_NAMESPACE
Chris@16:   using std::pow;
Chris@16:   using std::exp;
Chris@16: #endif
Chris@16: 
Chris@16:   typedef typename graph_traits<VertexListAndIncidenceGraph>::vertex_iterator
Chris@16:     vertex_iterator;
Chris@16:   typedef typename graph_traits<VertexListAndIncidenceGraph>::vertex_descriptor
Chris@16:     vertex_descriptor;
Chris@16:   typedef typename Topology::point_type point_type;
Chris@16:   vertex_iterator i, iend;
Chris@16:   std::vector<double> distance_from_input_vector(num_vertices(graph));
Chris@16:   typedef boost::iterator_property_map<std::vector<double>::iterator, 
Chris@16:                                        VertexIndexMap,
Chris@16:                                        double, double&>
Chris@16:     DistanceFromInputMap;
Chris@16:   DistanceFromInputMap distance_from_input(distance_from_input_vector.begin(),
Chris@16:                                            vertex_index_map);
Chris@16:   std::vector<double> node_distance_map_vector(num_vertices(graph));
Chris@16:   typedef boost::iterator_property_map<std::vector<double>::iterator, 
Chris@16:                                        VertexIndexMap,
Chris@16:                                        double, double&>
Chris@16:     NodeDistanceMap;
Chris@16:   NodeDistanceMap node_distance(node_distance_map_vector.begin(),
Chris@16:                                 vertex_index_map);
Chris@16:   point_type input_vector = space.random_point();
Chris@16:   vertex_descriptor min_distance_loc 
Chris@16:     = graph_traits<VertexListAndIncidenceGraph>::null_vertex();
Chris@16:   double min_distance = 0.0;
Chris@16:   bool min_distance_unset = true;
Chris@16:   for (boost::tie(i, iend) = vertices(graph); i != iend; ++i) {
Chris@16:     double this_distance = space.distance(get(position, *i), input_vector);
Chris@16:     put(distance_from_input, *i, this_distance);
Chris@16:     if (min_distance_unset || this_distance < min_distance) {
Chris@16:       min_distance = this_distance;
Chris@16:       min_distance_loc = *i;
Chris@16:     }
Chris@16:     min_distance_unset = false;
Chris@16:   }
Chris@16:   BOOST_ASSERT (!min_distance_unset); // Graph must have at least one vertex
Chris@16:   boost::detail::update_position_visitor<
Chris@16:       PositionMap, NodeDistanceMap, Topology,
Chris@16:       VertexListAndIncidenceGraph> 
Chris@16:     update_position(position, node_distance, space,
Chris@16:                     input_vector, diameter, learning_constant, 
Chris@16:                     exp(-1. / (2 * diameter * diameter)));
Chris@16:   std::fill(node_distance_map_vector.begin(), node_distance_map_vector.end(), 0);
Chris@16:   try {
Chris@16:     typedef detail::gursoy_shortest<EdgeWeightMap> shortest;
Chris@16:     shortest::run(graph, min_distance_loc, node_distance, update_position,
Chris@16:                   weight);    
Chris@16:   } catch (detail::over_distance_limit) { 
Chris@16:     /* Thrown to break out of BFS or Dijkstra early */ 
Chris@16:   }
Chris@16: }
Chris@16: 
Chris@16: template <typename VertexListAndIncidenceGraph,  typename Topology,
Chris@16:           typename PositionMap, typename VertexIndexMap, 
Chris@16:           typename EdgeWeightMap>
Chris@16: void gursoy_atun_refine(const VertexListAndIncidenceGraph& graph,  
Chris@16:                         const Topology& space,
Chris@16:                         PositionMap position,
Chris@16:                         int nsteps,
Chris@16:                         double diameter_initial,
Chris@16:                         double diameter_final,
Chris@16:                         double learning_constant_initial,
Chris@16:                         double learning_constant_final,
Chris@16:                         VertexIndexMap vertex_index_map,
Chris@16:                         EdgeWeightMap weight) 
Chris@16: {
Chris@16: #ifndef BOOST_NO_STDC_NAMESPACE
Chris@16:   using std::pow;
Chris@16:   using std::exp;
Chris@16: #endif
Chris@16: 
Chris@16:   typedef typename graph_traits<VertexListAndIncidenceGraph>::vertex_iterator
Chris@16:     vertex_iterator;
Chris@16:   vertex_iterator i, iend;
Chris@16:   double diameter_ratio = (double)diameter_final / diameter_initial;
Chris@16:   double learning_constant_ratio = 
Chris@16:     learning_constant_final / learning_constant_initial;
Chris@16:   std::vector<double> distance_from_input_vector(num_vertices(graph));
Chris@16:   typedef boost::iterator_property_map<std::vector<double>::iterator, 
Chris@16:                                        VertexIndexMap,
Chris@16:                                        double, double&>
Chris@16:     DistanceFromInputMap;
Chris@16:   DistanceFromInputMap distance_from_input(distance_from_input_vector.begin(),
Chris@16:                                            vertex_index_map);
Chris@16:   std::vector<int> node_distance_map_vector(num_vertices(graph));
Chris@16:   typedef boost::iterator_property_map<std::vector<int>::iterator, 
Chris@16:                                        VertexIndexMap, double, double&>
Chris@16:     NodeDistanceMap;
Chris@16:   NodeDistanceMap node_distance(node_distance_map_vector.begin(),
Chris@16:                                 vertex_index_map);
Chris@16:   for (int round = 0; round < nsteps; ++round) {
Chris@16:     double part_done = (double)round / (nsteps - 1);
Chris@16:     // fprintf(stderr, "%2d%% done\n", int(rint(part_done * 100.)));
Chris@16:     int diameter = (int)(diameter_initial * pow(diameter_ratio, part_done));
Chris@16:     double learning_constant = 
Chris@16:       learning_constant_initial * pow(learning_constant_ratio, part_done);
Chris@16:     gursoy_atun_step(graph, space, position, diameter, learning_constant, 
Chris@16:                      vertex_index_map, weight);
Chris@16:   }
Chris@16: }
Chris@16: 
Chris@16: template <typename VertexListAndIncidenceGraph,  typename Topology,
Chris@16:           typename PositionMap, typename VertexIndexMap, 
Chris@16:           typename EdgeWeightMap>
Chris@16: void gursoy_atun_layout(const VertexListAndIncidenceGraph& graph,  
Chris@16:                         const Topology& space,
Chris@16:                         PositionMap position,
Chris@16:                         int nsteps,
Chris@16:                         double diameter_initial,
Chris@16:                         double diameter_final,
Chris@16:                         double learning_constant_initial,
Chris@16:                         double learning_constant_final,
Chris@16:                         VertexIndexMap vertex_index_map,
Chris@16:                         EdgeWeightMap weight)
Chris@16: {
Chris@16:   typedef typename graph_traits<VertexListAndIncidenceGraph>::vertex_iterator
Chris@16:     vertex_iterator;
Chris@16:   vertex_iterator i, iend;
Chris@16:   for (boost::tie(i, iend) = vertices(graph); i != iend; ++i) {
Chris@16:     put(position, *i, space.random_point());
Chris@16:   }
Chris@16:   gursoy_atun_refine(graph, space,
Chris@16:                      position, nsteps,
Chris@16:                      diameter_initial, diameter_final, 
Chris@16:                      learning_constant_initial, learning_constant_final,
Chris@16:                      vertex_index_map, weight);
Chris@16: }
Chris@16: 
Chris@16: template <typename VertexListAndIncidenceGraph,  typename Topology,
Chris@16:           typename PositionMap, typename VertexIndexMap>
Chris@16: void gursoy_atun_layout(const VertexListAndIncidenceGraph& graph,  
Chris@16:                         const Topology& space,
Chris@16:                         PositionMap position,
Chris@16:                         int nsteps,
Chris@16:                         double diameter_initial,
Chris@16:                         double diameter_final,
Chris@16:                         double learning_constant_initial,
Chris@16:                         double learning_constant_final,
Chris@16:                         VertexIndexMap vertex_index_map)
Chris@16: {
Chris@16:   gursoy_atun_layout(graph, space, position, nsteps, 
Chris@16:                      diameter_initial, diameter_final, 
Chris@16:                      learning_constant_initial, learning_constant_final, 
Chris@16:                      vertex_index_map, dummy_property_map());
Chris@16: }
Chris@16: 
Chris@16: template <typename VertexListAndIncidenceGraph, typename Topology,
Chris@16:           typename PositionMap>
Chris@16: void gursoy_atun_layout(const VertexListAndIncidenceGraph& graph,  
Chris@16:                         const Topology& space,
Chris@16:                         PositionMap position,
Chris@16:                         int nsteps,
Chris@16:                         double diameter_initial,
Chris@16:                         double diameter_final = 1.0,
Chris@16:                         double learning_constant_initial = 0.8,
Chris@16:                         double learning_constant_final = 0.2)
Chris@16: { 
Chris@16:   gursoy_atun_layout(graph, space, position, nsteps, diameter_initial,
Chris@16:                      diameter_final, learning_constant_initial,
Chris@16:                      learning_constant_final, get(vertex_index, graph)); 
Chris@16: }
Chris@16: 
Chris@16: template <typename VertexListAndIncidenceGraph, typename Topology,
Chris@16:           typename PositionMap>
Chris@16: void gursoy_atun_layout(const VertexListAndIncidenceGraph& graph,  
Chris@16:                         const Topology& space,
Chris@16:                         PositionMap position,
Chris@16:                         int nsteps)
Chris@16: {
Chris@16: #ifndef BOOST_NO_STDC_NAMESPACE
Chris@16:   using std::sqrt;
Chris@16: #endif
Chris@16: 
Chris@16:   gursoy_atun_layout(graph, space, position, nsteps, 
Chris@16:                      sqrt((double)num_vertices(graph)));
Chris@16: }
Chris@16: 
Chris@16: template <typename VertexListAndIncidenceGraph, typename Topology,
Chris@16:           typename PositionMap>
Chris@16: void gursoy_atun_layout(const VertexListAndIncidenceGraph& graph,  
Chris@16:                         const Topology& space,
Chris@16:                         PositionMap position)
Chris@16: {
Chris@16:   gursoy_atun_layout(graph, space, position, num_vertices(graph));
Chris@16: }
Chris@16: 
Chris@16: template<typename VertexListAndIncidenceGraph, typename Topology,
Chris@16:          typename PositionMap, typename P, typename T, typename R>
Chris@16: void 
Chris@16: gursoy_atun_layout(const VertexListAndIncidenceGraph& graph,  
Chris@16:                    const Topology& space,
Chris@16:                    PositionMap position,
Chris@16:                    const bgl_named_params<P,T,R>& params)
Chris@16: {
Chris@16: #ifndef BOOST_NO_STDC_NAMESPACE
Chris@16:   using std::sqrt;
Chris@16: #endif
Chris@16: 
Chris@16:   std::pair<double, double> diam(sqrt(double(num_vertices(graph))), 1.0);
Chris@16:   std::pair<double, double> learn(0.8, 0.2);
Chris@16:   gursoy_atun_layout(graph, space, position,
Chris@16:                      choose_param(get_param(params, iterations_t()),
Chris@16:                                   num_vertices(graph)),
Chris@16:                      choose_param(get_param(params, diameter_range_t()), 
Chris@16:                                   diam).first,
Chris@16:                      choose_param(get_param(params, diameter_range_t()), 
Chris@16:                                   diam).second,
Chris@16:                      choose_param(get_param(params, learning_constant_range_t()), 
Chris@16:                                   learn).first,
Chris@16:                      choose_param(get_param(params, learning_constant_range_t()), 
Chris@16:                                   learn).second,
Chris@16:                      choose_const_pmap(get_param(params, vertex_index), graph,
Chris@16:                                        vertex_index),
Chris@16:                      choose_param(get_param(params, edge_weight), 
Chris@16:                                   dummy_property_map()));
Chris@16: }
Chris@16: 
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #endif // BOOST_GRAPH_GURSOY_ATUN_LAYOUT_HPP