libcarla/include/system/boost/graph/create_condensation_graph.hpp
2024-10-18 13:19:59 +08:00

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C++

//=======================================================================
// Copyright 2002 Indiana University.
// 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)
//=======================================================================
#ifndef BOOST_CREATE_CONDENSATION_GRAPH_HPP
#define BOOST_CREATE_CONDENSATION_GRAPH_HPP
#include <boost/graph/graph_traits.hpp>
#include <boost/property_map/property_map.hpp>
namespace boost
{
template < typename Graph, typename ComponentLists, typename ComponentNumberMap,
typename CondensationGraph, typename EdgeMultiplicityMap >
void create_condensation_graph(const Graph& g, const ComponentLists& components,
ComponentNumberMap component_number, CondensationGraph& cg,
EdgeMultiplicityMap edge_mult_map)
{
typedef typename graph_traits< Graph >::vertex_descriptor vertex;
typedef typename graph_traits< Graph >::vertices_size_type size_type;
typedef
typename graph_traits< CondensationGraph >::vertex_descriptor cg_vertex;
std::vector< cg_vertex > to_cg_vertex(components.size());
for (size_type s = 0; s < components.size(); ++s)
to_cg_vertex[s] = add_vertex(cg);
for (size_type si = 0; si < components.size(); ++si)
{
cg_vertex s = to_cg_vertex[si];
std::vector< cg_vertex > adj;
for (size_type i = 0; i < components[si].size(); ++i)
{
vertex u = components[s][i];
typename graph_traits< Graph >::adjacency_iterator v, v_end;
for (boost::tie(v, v_end) = adjacent_vertices(u, g); v != v_end;
++v)
{
cg_vertex t = to_cg_vertex[component_number[*v]];
if (s != t) // Avoid loops in the condensation graph
adj.push_back(t);
}
}
std::sort(adj.begin(), adj.end());
if (!adj.empty())
{
size_type i = 0;
cg_vertex t = adj[i];
typename graph_traits< CondensationGraph >::edge_descriptor e;
bool inserted;
boost::tie(e, inserted) = add_edge(s, t, cg);
put(edge_mult_map, e, 1);
++i;
while (i < adj.size())
{
if (adj[i] == t)
put(edge_mult_map, e, get(edge_mult_map, e) + 1);
else
{
t = adj[i];
boost::tie(e, inserted) = add_edge(s, t, cg);
put(edge_mult_map, e, 1);
}
++i;
}
}
}
}
template < typename Graph, typename ComponentLists, typename ComponentNumberMap,
typename CondensationGraph >
void create_condensation_graph(const Graph& g, const ComponentLists& components,
ComponentNumberMap component_number, CondensationGraph& cg)
{
create_condensation_graph(
g, components, component_number, cg, dummy_property_map());
}
} // namespace boost
#endif // BOOST_CREATE_CONDENSATION_GRAPH_HPP