boost/graph/dijkstra_shortest_paths_no_color_map.hpp
//=======================================================================
// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
// Copyright 2009 Trustees of Indiana University.
// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek, Michael Hansen
//
// 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)
//=======================================================================
#ifndef BOOST_GRAPH_DIJKSTRA_NO_COLOR_MAP_HPP
#define BOOST_GRAPH_DIJKSTRA_NO_COLOR_MAP_HPP
#include <boost/pending/indirect_cmp.hpp>
#include <boost/graph/relax.hpp>
#include <boost/graph/detail/d_ary_heap.hpp>
#include <boost/graph/dijkstra_shortest_paths.hpp>
#include <boost/graph/iteration_macros.hpp>
namespace boost
{
// No init version
template < typename Graph, typename DijkstraVisitor, typename PredecessorMap,
typename DistanceMap, typename WeightMap, typename VertexIndexMap,
typename DistanceCompare, typename DistanceWeightCombine,
typename DistanceInfinity, typename DistanceZero >
void dijkstra_shortest_paths_no_color_map_no_init(const Graph& graph,
typename graph_traits< Graph >::vertex_descriptor start_vertex,
PredecessorMap predecessor_map, DistanceMap distance_map,
WeightMap weight_map, VertexIndexMap index_map,
DistanceCompare distance_compare,
DistanceWeightCombine distance_weight_combine,
DistanceInfinity distance_infinity, DistanceZero distance_zero,
DijkstraVisitor visitor)
{
typedef typename graph_traits< Graph >::vertex_descriptor Vertex;
typedef typename property_traits< DistanceMap >::value_type Distance;
typedef indirect_cmp< DistanceMap, DistanceCompare >
DistanceIndirectCompare;
DistanceIndirectCompare distance_indirect_compare(
distance_map, distance_compare);
// Default - use d-ary heap (d = 4)
typedef detail::vertex_property_map_generator< Graph, VertexIndexMap,
std::size_t >
IndexInHeapMapHelper;
typedef typename IndexInHeapMapHelper::type IndexInHeapMap;
typedef d_ary_heap_indirect< Vertex, 4, IndexInHeapMap, DistanceMap,
DistanceCompare >
VertexQueue;
boost::scoped_array< std::size_t > index_in_heap_map_holder;
IndexInHeapMap index_in_heap = IndexInHeapMapHelper::build(
graph, index_map, index_in_heap_map_holder);
VertexQueue vertex_queue(distance_map, index_in_heap, distance_compare);
// Add vertex to the queue
vertex_queue.push(start_vertex);
// Starting vertex will always be the first discovered vertex
visitor.discover_vertex(start_vertex, graph);
while (!vertex_queue.empty())
{
Vertex min_vertex = vertex_queue.top();
vertex_queue.pop();
visitor.examine_vertex(min_vertex, graph);
// Check if any other vertices can be reached
Distance min_vertex_distance = get(distance_map, min_vertex);
if (!distance_compare(min_vertex_distance, distance_infinity))
{
// This is the minimum vertex, so all other vertices are unreachable
return;
}
// Examine neighbors of min_vertex
BGL_FORALL_OUTEDGES_T(min_vertex, current_edge, graph, Graph)
{
visitor.examine_edge(current_edge, graph);
// Check if the edge has a negative weight
if (distance_compare(get(weight_map, current_edge), distance_zero))
{
boost::throw_exception(negative_edge());
}
// Extract the neighboring vertex and get its distance
Vertex neighbor_vertex = target(current_edge, graph);
Distance neighbor_vertex_distance
= get(distance_map, neighbor_vertex);
bool is_neighbor_undiscovered = !distance_compare(
neighbor_vertex_distance, distance_infinity);
// Attempt to relax the edge
bool was_edge_relaxed
= relax_target(current_edge, graph, weight_map, predecessor_map,
distance_map, distance_weight_combine, distance_compare);
if (was_edge_relaxed)
{
visitor.edge_relaxed(current_edge, graph);
if (is_neighbor_undiscovered)
{
visitor.discover_vertex(neighbor_vertex, graph);
vertex_queue.push(neighbor_vertex);
}
else
{
vertex_queue.update(neighbor_vertex);
}
}
else
{
visitor.edge_not_relaxed(current_edge, graph);
}
} // end out edge iteration
visitor.finish_vertex(min_vertex, graph);
} // end while queue not empty
}
// Full init version
template < typename Graph, typename DijkstraVisitor, typename PredecessorMap,
typename DistanceMap, typename WeightMap, typename VertexIndexMap,
typename DistanceCompare, typename DistanceWeightCombine,
typename DistanceInfinity, typename DistanceZero >
void dijkstra_shortest_paths_no_color_map(const Graph& graph,
typename graph_traits< Graph >::vertex_descriptor start_vertex,
PredecessorMap predecessor_map, DistanceMap distance_map,
WeightMap weight_map, VertexIndexMap index_map,
DistanceCompare distance_compare,
DistanceWeightCombine distance_weight_combine,
DistanceInfinity distance_infinity, DistanceZero distance_zero,
DijkstraVisitor visitor)
{
// Initialize vertices
BGL_FORALL_VERTICES_T(current_vertex, graph, Graph)
{
visitor.initialize_vertex(current_vertex, graph);
// Default all distances to infinity
put(distance_map, current_vertex, distance_infinity);
// Default all vertex predecessors to the vertex itself
put(predecessor_map, current_vertex, current_vertex);
}
// Set distance for start_vertex to zero
put(distance_map, start_vertex, distance_zero);
// Pass everything on to the no_init version
dijkstra_shortest_paths_no_color_map_no_init(graph, start_vertex,
predecessor_map, distance_map, weight_map, index_map, distance_compare,
distance_weight_combine, distance_infinity, distance_zero, visitor);
}
namespace detail
{
// Handle defaults for PredecessorMap, DistanceCompare,
// DistanceWeightCombine, DistanceInfinity and DistanceZero
template < typename Graph, typename DistanceMap, typename WeightMap,
typename VertexIndexMap, typename Params >
inline void dijkstra_no_color_map_dispatch2(const Graph& graph,
typename graph_traits< Graph >::vertex_descriptor start_vertex,
DistanceMap distance_map, WeightMap weight_map,
VertexIndexMap index_map, const Params& params)
{
// Default for predecessor map
dummy_property_map predecessor_map;
typedef
typename property_traits< DistanceMap >::value_type DistanceType;
DistanceType inf = choose_param(get_param(params, distance_inf_t()),
(std::numeric_limits< DistanceType >::max)());
dijkstra_shortest_paths_no_color_map(graph, start_vertex,
choose_param(
get_param(params, vertex_predecessor), predecessor_map),
distance_map, weight_map, index_map,
choose_param(get_param(params, distance_compare_t()),
std::less< DistanceType >()),
choose_param(get_param(params, distance_combine_t()),
std::plus< DistanceType >()),
inf,
choose_param(get_param(params, distance_zero_t()), DistanceType()),
choose_param(get_param(params, graph_visitor),
make_dijkstra_visitor(null_visitor())));
}
template < typename Graph, typename DistanceMap, typename WeightMap,
typename IndexMap, typename Params >
inline void dijkstra_no_color_map_dispatch1(const Graph& graph,
typename graph_traits< Graph >::vertex_descriptor start_vertex,
DistanceMap distance_map, WeightMap weight_map, IndexMap index_map,
const Params& params)
{
// Default for distance map
typedef typename property_traits< WeightMap >::value_type DistanceType;
typename std::vector< DistanceType >::size_type vertex_count
= is_default_param(distance_map) ? num_vertices(graph) : 1;
std::vector< DistanceType > default_distance_map(vertex_count);
detail::dijkstra_no_color_map_dispatch2(graph, start_vertex,
choose_param(distance_map,
make_iterator_property_map(default_distance_map.begin(),
index_map, default_distance_map[0])),
weight_map, index_map, params);
}
} // namespace detail
// Named parameter version
template < typename Graph, typename Param, typename Tag, typename Rest >
inline void dijkstra_shortest_paths_no_color_map(const Graph& graph,
typename graph_traits< Graph >::vertex_descriptor start_vertex,
const bgl_named_params< Param, Tag, Rest >& params)
{
// Default for edge weight and vertex index map is to ask for them
// from the graph. Default for the visitor is null_visitor.
detail::dijkstra_no_color_map_dispatch1(graph, start_vertex,
get_param(params, vertex_distance),
choose_const_pmap(get_param(params, edge_weight), graph, edge_weight),
choose_const_pmap(get_param(params, vertex_index), graph, vertex_index),
params);
}
} // namespace boost
#endif // BOOST_GRAPH_DIJKSTRA_NO_COLOR_MAP_HPP