test: epoc32/include/stdapis/boost/graph/johnson_all_pairs

     1 //=======================================================================

     2 // Copyright 1997, 1998, 1999, 2000 University of Notre Dame.

     3 // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek

     4 //

     5 // Distributed under the Boost Software License, Version 1.0. (See

     6 // accompanying file LICENSE_1_0.txt or copy at

     7 // http://www.boost.org/LICENSE_1_0.txt)

     8 //=======================================================================

    10 /*

    11   This file implements the function

    13   template <class VertexAndEdgeListGraph, class DistanceMatrix,

    14             class P, class T, class R>

    15   bool

    16   johnson_all_pairs_shortest_paths

    17     (VertexAndEdgeListGraph& g,

    18      DistanceMatrix& D,

    19      const bgl_named_params<P, T, R>& params)

    20  */

    22 #ifndef BOOST_GRAPH_JOHNSON_HPP

    23 #define BOOST_GRAPH_JOHNSON_HPP

    25 #include <boost/graph/graph_traits.hpp>

    26 #include <boost/property_map.hpp>

    27 #include <boost/graph/bellman_ford_shortest_paths.hpp>

    28 #include <boost/graph/dijkstra_shortest_paths.hpp>

    29 #include <boost/graph/adjacency_list.hpp>

    30 #include <boost/pending/ct_if.hpp>

    31 #include <boost/type_traits/same_traits.hpp>

    33 namespace boost {

    35   template <class VertexAndEdgeListGraph, class DistanceMatrix,

    36             class VertexID, class Weight, typename BinaryPredicate,

    37             typename BinaryFunction, typename Infinity, class DistanceZero>

    38   bool

    39   johnson_all_pairs_shortest_paths(VertexAndEdgeListGraph& g1,

    40                DistanceMatrix& D,

    41                VertexID id1, Weight w1, const BinaryPredicate& compare,

    42                const BinaryFunction& combine, const Infinity& inf,

    43                DistanceZero zero)

    44   {

    45     typedef graph_traits<VertexAndEdgeListGraph> Traits1;

    46     typedef typename property_traits<Weight>::value_type DT;

    47     function_requires< BasicMatrixConcept<DistanceMatrix,

    48       typename Traits1::vertices_size_type, DT> >();

    50     typedef typename Traits1::directed_category DirCat;

    51     bool is_undirected = is_same<DirCat, undirected_tag>::value;

    53     typedef adjacency_list<vecS, vecS, directedS,

    54       property< vertex_distance_t, DT>,

    55       property< edge_weight_t, DT,

    56       property< edge_weight2_t, DT > > > Graph2;

    57     typedef graph_traits<Graph2> Traits2;

    59     Graph2 g2(num_vertices(g1) + 1);

    60     typename property_map<Graph2, edge_weight_t>::type

    61       w = get(edge_weight, g2);

    62     typename property_map<Graph2, edge_weight2_t>::type

    63       w_hat = get(edge_weight2, g2);

    64     typename property_map<Graph2, vertex_distance_t>::type

    65       d = get(vertex_distance, g2);

    66     typedef typename property_map<Graph2, vertex_index_t>::type VertexID2;

    67     VertexID2 id2 = get(vertex_index, g2);

    69     // Construct g2 where V[g2] = V[g1] U {s}

    70     //   and  E[g2] = E[g1] U {(s,v)| v in V[g1]}

    71     std::vector<typename Traits1::vertex_descriptor>

    72       verts1(num_vertices(g1) + 1);

    73     typename Traits2::vertex_descriptor s = *vertices(g2).first;

    74     {

    75       typename Traits1::vertex_iterator v, v_end;

    76       int i = 1;

    77       for (tie(v, v_end) = vertices(g1); v != v_end; ++v, ++i) {

    78         typename Traits2::edge_descriptor e; bool z;

    79         tie(e, z) = add_edge(s, get(id1, *v) + 1, g2);

    80         put(w, e, zero);

    81         verts1[i] = *v;

    82       }

    83       typename Traits1::edge_iterator e, e_end;

    84       for (tie(e, e_end) = edges(g1); e != e_end; ++e) {

    85         typename Traits2::edge_descriptor e2; bool z;

    86         tie(e2, z) = add_edge(get(id1, source(*e, g1)) + 1,

    87                               get(id1, target(*e, g1)) + 1, g2);

    88         put(w, e2, get(w1, *e));

    89         if (is_undirected) {

    90           tie(e2, z) = add_edge(get(id1, target(*e, g1)) + 1,

    91                                 get(id1, source(*e, g1)) + 1, g2);

    92           put(w, e2, get(w1, *e));

    93         }

    94       }

    95     }

    96     typename Traits2::vertex_iterator v, v_end, u, u_end;

    97     typename Traits2::edge_iterator e, e_end;

    98     std::vector<DT> h_vec(num_vertices(g2));

    99     typedef typename std::vector<DT>::iterator iter_t;

   100     iterator_property_map<iter_t,VertexID2,DT,DT&> h(h_vec.begin(), id2);

   102     for (tie(v, v_end) = vertices(g2); v != v_end; ++v)

   103       d[*v] = inf;

   105     put(d, s, zero);

   106     // Using the non-named parameter versions of bellman_ford and

   107     // dijkstra for portability reasons.

   108     dummy_property_map pred; bellman_visitor<> bvis;

   109     if (bellman_ford_shortest_paths

   110         (g2, num_vertices(g2), w, pred, d, combine, compare, bvis)) {

   111       for (tie(v, v_end) = vertices(g2); v != v_end; ++v)

   112         put(h, *v, get(d, *v));

   113       // Reweight the edges to remove negatives

   114       for (tie(e, e_end) = edges(g2); e != e_end; ++e) {

   115         typename Traits2::vertex_descriptor a = source(*e, g2),

   116           b = target(*e, g2);

   117         put(w_hat, *e, get(w, *e) + get(h, a) - get(h, b));

   118       }

   119       for (tie(u, u_end) = vertices(g2); u != u_end; ++u) {

   120         dijkstra_visitor<> dvis;

   121         dijkstra_shortest_paths

   122           (g2, *u, pred, d, w_hat, id2, compare, combine, inf, zero,dvis);

   123         for (tie(v, v_end) = vertices(g2); v != v_end; ++v) {

   124           if (*u != s && *v != s) {

   125             typename Traits1::vertex_descriptor u1, v1;

   126             u1 = verts1[id2[*u]]; v1 = verts1[id2[*v]];

   127             D[id2[*u]-1][id2[*v]-1] = get(d, *v) + get(h, *v) - get(h, *u);

   128           }

   129         }

   130       }

   131       return true;

   132     } else

   133       return false;

   134   }

   136   template <class VertexAndEdgeListGraph, class DistanceMatrix,

   137             class VertexID, class Weight, class DistanceZero>

   138   bool

   139   johnson_all_pairs_shortest_paths(VertexAndEdgeListGraph& g1,

   140                DistanceMatrix& D,

   141                VertexID id1, Weight w1, DistanceZero zero)

   142   {

   143     typedef typename property_traits<Weight>::value_type WT;

   144     return johnson_all_pairs_shortest_paths(g1, D, id1, w1,

   145                                             std::less<WT>(),

   146                                             closed_plus<WT>(),

   147                                             (std::numeric_limits<WT>::max)(),

   148                                             zero);

   149   }

   151   namespace detail {

   153     template <class VertexAndEdgeListGraph, class DistanceMatrix,

   154               class P, class T, class R, class Weight,

   155               class VertexID>

   156     bool

   157     johnson_dispatch(VertexAndEdgeListGraph& g,

   158                      DistanceMatrix& D,

   159                      const bgl_named_params<P, T, R>& params,

   160                      Weight w, VertexID id)

   161     {

   162       typedef typename property_traits<Weight>::value_type WT;

   164       return johnson_all_pairs_shortest_paths

   165         (g, D, id, w,

   166         choose_param(get_param(params, distance_compare_t()),

   167           std::less<WT>()),

   168         choose_param(get_param(params, distance_combine_t()),

   169           closed_plus<WT>()),

   170         choose_param(get_param(params, distance_inf_t()),

   171           std::numeric_limits<WT>::max BOOST_PREVENT_MACRO_SUBSTITUTION()),

   172          choose_param(get_param(params, distance_zero_t()), WT()) );

   173     }

   175   } // namespace detail

   177   template <class VertexAndEdgeListGraph, class DistanceMatrix,

   178             class P, class T, class R>

   179   bool

   180   johnson_all_pairs_shortest_paths

   181     (VertexAndEdgeListGraph& g,

   182      DistanceMatrix& D,

   183      const bgl_named_params<P, T, R>& params)

   184   {

   185     return detail::johnson_dispatch

   186       (g, D, params,

   187        choose_const_pmap(get_param(params, edge_weight), g, edge_weight),

   188        choose_const_pmap(get_param(params, vertex_index), g, vertex_index)

   189        );

   190   }

   192   template <class VertexAndEdgeListGraph, class DistanceMatrix>

   193   bool

   194   johnson_all_pairs_shortest_paths

   195     (VertexAndEdgeListGraph& g, DistanceMatrix& D)

   196   {

   197     bgl_named_params<int,int> params(1);

   198     return detail::johnson_dispatch

   199       (g, D, params, get(edge_weight, g), get(vertex_index, g));

   200   }

   202 } // namespace boost

   204 #endif // BOOST_GRAPH_JOHNSON_HPP

author	William Roberts <williamr@symbian.org>
	Wed, 31 Mar 2010 12:33:34 +0100 (2010-03-31)
branch	Symbian3
changeset 4	837f303aceeb
permissions	-rw-r--r--