boost/graph/johnson_all_pairs_shortest.hpp
//=======================================================================
// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
//
// This file is part of the Boost Graph Library
//
// You should have received a copy of the License Agreement for the
// Boost Graph Library along with the software; see the file LICENSE.
// If not, contact Office of Research, University of Notre Dame, Notre
// Dame, IN 46556.
//
// Permission to modify the code and to distribute modified code is
// granted, provided the text of this NOTICE is retained, a notice that
// the code was modified is included with the above COPYRIGHT NOTICE and
// with the COPYRIGHT NOTICE in the LICENSE file, and that the LICENSE
// file is distributed with the modified code.
//
// LICENSOR MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.
// By way of example, but not limitation, Licensor MAKES NO
// REPRESENTATIONS OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY
// PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED SOFTWARE COMPONENTS
// OR DOCUMENTATION WILL NOT INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS
// OR OTHER RIGHTS.
//=======================================================================
/*
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.hpp>
#include <boost/graph/bellman_ford_shortest_paths.hpp>
#include <boost/graph/dijkstra_shortest_paths.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <boost/pending/ct_if.hpp>
#include <boost/type_traits/same_traits.hpp>
namespace boost {
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 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 (tie(v, v_end) = vertices(g1); v != v_end; ++v, ++i) {
typename Traits2::edge_descriptor e; bool z;
tie(e, z) = add_edge(s, id1[*v] + 1, g2);
w[e] = zero;
verts1[i] = *v;
}
typename Traits1::edge_iterator e, e_end;
for (tie(e, e_end) = edges(g1); e != e_end; ++e) {
typename Traits2::edge_descriptor e2; bool z;
tie(e2, z) = add_edge(id1[source(*e, g1)] + 1,
id1[target(*e, g1)] + 1, g2);
w[e2] = get(w1, *e);
if (is_undirected) {
tie(e2, z) = add_edge(id1[target(*e, g1)] + 1,
id1[source(*e, g1)] + 1, g2);
w[e2] = get(w1, *e);
}
}
}
typename Traits2::vertex_iterator v, v_end, u, u_end;
typename Traits2::edge_iterator e, e_end;
std::vector<DT> h_vec(num_vertices(g2));
typedef typename std::vector<DT>::iterator iter_t;
iterator_property_map<iter_t,VertexID2,DT,DT&> h(h_vec.begin(), id2);
DT inf = (std::numeric_limits<DT>::max)();
for (tie(v, v_end) = vertices(g2); v != v_end; ++v)
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; closed_plus<DT> combine;
std::less<DT> compare; bellman_visitor<> bvis;
if (bellman_ford_shortest_paths
(g2, num_vertices(g2), w, pred, d, combine, compare, bvis)) {
for (tie(v, v_end) = vertices(g2); v != v_end; ++v)
put(h, *v, get(d, *v));
// Reweight the edges to remove negatives
for (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, get(w, *e) + get(h, a) - get(h, b));
}
for (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 (tie(v, v_end) = vertices(g2); v != v_end; ++v) {
if (*u != s && *v != s) {
typename Traits1::vertex_descriptor u1, v1;
u1 = verts1[id2[*u]]; v1 = verts1[id2[*v]];
D[id2[*u]-1][id2[*v]-1] = get(d, *v) + get(h, *v) - get(h, *u);
}
}
}
return true;
} else
return false;
}
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_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