| //======================================================================= | |
| // Copyright 1997, 1998, 1999, 2000 University of Notre Dame. | |
| // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek | |
| // | |
| // Distributed under the Boost Software License, Version 1.0. (See | |
| // accompanying file LICENSE_1_0.txt or copy at | |
| // http://www.boost.org/LICENSE_1_0.txt) | |
| //======================================================================= | |
| /* | |
| This file implements the function | |
| template <class VertexAndEdgeListGraph, class DistanceMatrix, | |
| class P, class T, class R> | |
| bool | |
| johnson_all_pairs_shortest_paths | |
| (VertexAndEdgeListGraph& g, | |
| DistanceMatrix& D, | |
| const bgl_named_params<P, T, R>& params) | |
| */ | |
| #ifndef BOOST_GRAPH_JOHNSON_HPP | |
| #define BOOST_GRAPH_JOHNSON_HPP | |
| #include <boost/graph/graph_traits.hpp> | |
| #include <boost/property_map/property_map.hpp> | |
| #include <boost/property_map/shared_array_property_map.hpp> | |
| #include <boost/graph/bellman_ford_shortest_paths.hpp> | |
| #include <boost/graph/dijkstra_shortest_paths.hpp> | |
| #include <boost/graph/adjacency_list.hpp> | |
| #include <boost/type_traits/same_traits.hpp> | |
| namespace boost { | |
| template <class VertexAndEdgeListGraph, class DistanceMatrix, | |
| class VertexID, class Weight, typename BinaryPredicate, | |
| typename BinaryFunction, typename Infinity, class DistanceZero> | |
| bool | |
| johnson_all_pairs_shortest_paths(VertexAndEdgeListGraph& g1, | |
| DistanceMatrix& D, | |
| VertexID id1, Weight w1, const BinaryPredicate& compare, | |
| const BinaryFunction& combine, const Infinity& inf, | |
| DistanceZero zero) | |
| { | |
| typedef graph_traits<VertexAndEdgeListGraph> Traits1; | |
| typedef typename property_traits<Weight>::value_type DT; | |
| function_requires< BasicMatrixConcept<DistanceMatrix, | |
| typename Traits1::vertices_size_type, DT> >(); | |
| typedef typename Traits1::directed_category DirCat; | |
| bool is_undirected = is_same<DirCat, undirected_tag>::value; | |
| typedef adjacency_list<vecS, vecS, directedS, | |
| property< vertex_distance_t, DT>, | |
| property< edge_weight_t, DT, | |
| property< edge_weight2_t, DT > > > Graph2; | |
| typedef graph_traits<Graph2> Traits2; | |
| Graph2 g2(num_vertices(g1) + 1); | |
| typename property_map<Graph2, edge_weight_t>::type | |
| w = get(edge_weight, g2); | |
| typename property_map<Graph2, edge_weight2_t>::type | |
| w_hat = get(edge_weight2, g2); | |
| typename property_map<Graph2, vertex_distance_t>::type | |
| d = get(vertex_distance, g2); | |
| typedef typename property_map<Graph2, vertex_index_t>::type VertexID2; | |
| VertexID2 id2 = get(vertex_index, g2); | |
| // Construct g2 where V[g2] = V[g1] U {s} | |
| // and E[g2] = E[g1] U {(s,v)| v in V[g1]} | |
| std::vector<typename Traits1::vertex_descriptor> | |
| verts1(num_vertices(g1) + 1); | |
| typename Traits2::vertex_descriptor s = *vertices(g2).first; | |
| { | |
| typename Traits1::vertex_iterator v, v_end; | |
| int i = 1; | |
| for (boost::tie(v, v_end) = vertices(g1); v != v_end; ++v, ++i) { | |
| typename Traits2::edge_descriptor e; bool z; | |
| boost::tie(e, z) = add_edge(s, get(id1, *v) + 1, g2); | |
| put(w, e, zero); | |
| verts1[i] = *v; | |
| } | |
| typename Traits1::edge_iterator e, e_end; | |
| for (boost::tie(e, e_end) = edges(g1); e != e_end; ++e) { | |
| typename Traits2::edge_descriptor e2; bool z; | |
| boost::tie(e2, z) = add_edge(get(id1, source(*e, g1)) + 1, | |
| get(id1, target(*e, g1)) + 1, g2); | |
| put(w, e2, get(w1, *e)); | |
| if (is_undirected) { | |
| boost::tie(e2, z) = add_edge(get(id1, target(*e, g1)) + 1, | |
| get(id1, source(*e, g1)) + 1, g2); | |
| put(w, e2, get(w1, *e)); | |
| } | |
| } | |
| } | |
| typename Traits2::vertex_iterator v, v_end, u, u_end; | |
| typename Traits2::edge_iterator e, e_end; | |
| shared_array_property_map<DT,VertexID2> h(num_vertices(g2), id2); | |
| for (boost::tie(v, v_end) = vertices(g2); v != v_end; ++v) | |
| put(d, *v, inf); | |
| put(d, s, zero); | |
| // Using the non-named parameter versions of bellman_ford and | |
| // dijkstra for portability reasons. | |
| dummy_property_map pred; bellman_visitor<> bvis; | |
| if (bellman_ford_shortest_paths | |
| (g2, num_vertices(g2), w, pred, d, combine, compare, bvis)) { | |
| for (boost::tie(v, v_end) = vertices(g2); v != v_end; ++v) | |
| put(h, *v, get(d, *v)); | |
| // Reweight the edges to remove negatives | |
| for (boost::tie(e, e_end) = edges(g2); e != e_end; ++e) { | |
| typename Traits2::vertex_descriptor a = source(*e, g2), | |
| b = target(*e, g2); | |
| put(w_hat, *e, combine(get(w, *e), (get(h, a) - get(h, b)))); | |
| } | |
| for (boost::tie(u, u_end) = vertices(g2); u != u_end; ++u) { | |
| dijkstra_visitor<> dvis; | |
| dijkstra_shortest_paths | |
| (g2, *u, pred, d, w_hat, id2, compare, combine, inf, zero,dvis); | |
| for (boost::tie(v, v_end) = vertices(g2); v != v_end; ++v) { | |
| if (*u != s && *v != s) { | |
| typename Traits1::vertex_descriptor u1, v1; | |
| u1 = verts1[get(id2, *u)]; v1 = verts1[get(id2, *v)]; | |
| D[get(id2, *u)-1][get(id2, *v)-1] = combine(get(d, *v), (get(h, *v) - get(h, *u))); | |
| } | |
| } | |
| } | |
| return true; | |
| } else | |
| return false; | |
| } | |
| template <class VertexAndEdgeListGraph, class DistanceMatrix, | |
| class VertexID, class Weight, class DistanceZero> | |
| bool | |
| johnson_all_pairs_shortest_paths(VertexAndEdgeListGraph& g1, | |
| DistanceMatrix& D, | |
| VertexID id1, Weight w1, DistanceZero zero) | |
| { | |
| typedef typename property_traits<Weight>::value_type WT; | |
| return johnson_all_pairs_shortest_paths(g1, D, id1, w1, | |
| std::less<WT>(), | |
| closed_plus<WT>(), | |
| (std::numeric_limits<WT>::max)(), | |
| zero); | |
| } | |
| namespace detail { | |
| template <class VertexAndEdgeListGraph, class DistanceMatrix, | |
| class P, class T, class R, class Weight, | |
| class VertexID> | |
| bool | |
| johnson_dispatch(VertexAndEdgeListGraph& g, | |
| DistanceMatrix& D, | |
| const bgl_named_params<P, T, R>& params, | |
| Weight w, VertexID id) | |
| { | |
| typedef typename property_traits<Weight>::value_type WT; | |
| return johnson_all_pairs_shortest_paths | |
| (g, D, id, w, | |
| choose_param(get_param(params, distance_compare_t()), | |
| std::less<WT>()), | |
| choose_param(get_param(params, distance_combine_t()), | |
| closed_plus<WT>()), | |
| choose_param(get_param(params, distance_inf_t()), | |
| std::numeric_limits<WT>::max BOOST_PREVENT_MACRO_SUBSTITUTION()), | |
| choose_param(get_param(params, distance_zero_t()), WT()) ); | |
| } | |
| } // namespace detail | |
| template <class VertexAndEdgeListGraph, class DistanceMatrix, | |
| class P, class T, class R> | |
| bool | |
| johnson_all_pairs_shortest_paths | |
| (VertexAndEdgeListGraph& g, | |
| DistanceMatrix& D, | |
| const bgl_named_params<P, T, R>& params) | |
| { | |
| return detail::johnson_dispatch | |
| (g, D, params, | |
| choose_const_pmap(get_param(params, edge_weight), g, edge_weight), | |
| choose_const_pmap(get_param(params, vertex_index), g, vertex_index) | |
| ); | |
| } | |
| template <class VertexAndEdgeListGraph, class DistanceMatrix> | |
| bool | |
| johnson_all_pairs_shortest_paths | |
| (VertexAndEdgeListGraph& g, DistanceMatrix& D) | |
| { | |
| bgl_named_params<int,int> params(1); | |
| return detail::johnson_dispatch | |
| (g, D, params, get(edge_weight, g), get(vertex_index, g)); | |
| } | |
| } // namespace boost | |
| #endif // BOOST_GRAPH_JOHNSON_HPP | |