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This is the documentation for a snapshot of the develop branch, built from commit 7321adb29d.

boost/graph/graph_utility.hpp

//
//=======================================================================
// 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)
//=======================================================================
//
#ifndef BOOST_GRAPH_UTILITY_HPP
#define BOOST_GRAPH_UTILITY_HPP

#include <stdlib.h>
#include <iostream>
#include <algorithm>
#include <assert.h>
#include <boost/config.hpp>
#include <boost/tuple/tuple.hpp>

#include <boost/graph/graph_traits.hpp>
#include <boost/graph/properties.hpp>
#include <boost/pending/container_traits.hpp>
#include <boost/graph/depth_first_search.hpp>
// iota moved to detail/algorithm.hpp
#include <boost/detail/algorithm.hpp>

namespace boost
{

// Provide an undirected graph interface alternative to the
// the source() and target() edge functions.
template < class UndirectedGraph >
inline std::pair< typename graph_traits< UndirectedGraph >::vertex_descriptor,
    typename graph_traits< UndirectedGraph >::vertex_descriptor >
incident(typename graph_traits< UndirectedGraph >::edge_descriptor e,
    UndirectedGraph& g)
{
    return std::make_pair(source(e, g), target(e, g));
}

// Provide an undirected graph interface alternative
// to the out_edges() function.
template < class Graph >
inline std::pair< typename graph_traits< Graph >::out_edge_iterator,
    typename graph_traits< Graph >::out_edge_iterator >
incident_edges(typename graph_traits< Graph >::vertex_descriptor u, Graph& g)
{
    return out_edges(u, g);
}

template < class Graph >
inline typename graph_traits< Graph >::vertex_descriptor opposite(
    typename graph_traits< Graph >::edge_descriptor e,
    typename graph_traits< Graph >::vertex_descriptor v, const Graph& g)
{
    typedef typename graph_traits< Graph >::vertex_descriptor vertex_descriptor;
    if (v == source(e, g))
        return target(e, g);
    else if (v == target(e, g))
        return source(e, g);
    else
        return vertex_descriptor();
}

//===========================================================================
// Some handy predicates

template < typename Vertex, typename Graph > struct incident_from_predicate
{
    incident_from_predicate(Vertex u, const Graph& g) : m_u(u), m_g(g) {}
    template < class Edge > bool operator()(const Edge& e) const
    {
        return source(e, m_g) == m_u;
    }
    Vertex m_u;
    const Graph& m_g;
};
template < typename Vertex, typename Graph >
inline incident_from_predicate< Vertex, Graph > incident_from(
    Vertex u, const Graph& g)
{
    return incident_from_predicate< Vertex, Graph >(u, g);
}

template < typename Vertex, typename Graph > struct incident_to_predicate
{
    incident_to_predicate(Vertex u, const Graph& g) : m_u(u), m_g(g) {}
    template < class Edge > bool operator()(const Edge& e) const
    {
        return target(e, m_g) == m_u;
    }
    Vertex m_u;
    const Graph& m_g;
};
template < typename Vertex, typename Graph >
inline incident_to_predicate< Vertex, Graph > incident_to(
    Vertex u, const Graph& g)
{
    return incident_to_predicate< Vertex, Graph >(u, g);
}

template < typename Vertex, typename Graph > struct incident_on_predicate
{
    incident_on_predicate(Vertex u, const Graph& g) : m_u(u), m_g(g) {}
    template < class Edge > bool operator()(const Edge& e) const
    {
        return source(e, m_g) == m_u || target(e, m_g) == m_u;
    }
    Vertex m_u;
    const Graph& m_g;
};
template < typename Vertex, typename Graph >
inline incident_on_predicate< Vertex, Graph > incident_on(
    Vertex u, const Graph& g)
{
    return incident_on_predicate< Vertex, Graph >(u, g);
}

template < typename Vertex, typename Graph > struct connects_predicate
{
    connects_predicate(Vertex u, Vertex v, const Graph& g)
    : m_u(u), m_v(v), m_g(g)
    {
    }
    template < class Edge > bool operator()(const Edge& e) const
    {
        if (is_directed(m_g))
            return source(e, m_g) == m_u && target(e, m_g) == m_v;
        else
            return (source(e, m_g) == m_u && target(e, m_g) == m_v)
                || (source(e, m_g) == m_v && target(e, m_g) == m_u);
    }
    Vertex m_u, m_v;
    const Graph& m_g;
};
template < typename Vertex, typename Graph >
inline connects_predicate< Vertex, Graph > connects(
    Vertex u, Vertex v, const Graph& g)
{
    return connects_predicate< Vertex, Graph >(u, v, g);
}

// Need to convert all of these printing functions to take an ostream object
// -JGS

template < class IncidenceGraph, class Name >
void print_in_edges(
    const IncidenceGraph& G, Name name, std::ostream& os = std::cout)
{
    typename graph_traits< IncidenceGraph >::vertex_iterator ui, ui_end;
    for (boost::tie(ui, ui_end) = vertices(G); ui != ui_end; ++ui)
    {
        os << get(name, *ui) << " <-- ";
        typename graph_traits< IncidenceGraph >::in_edge_iterator ei, ei_end;
        for (boost::tie(ei, ei_end) = in_edges(*ui, G); ei != ei_end; ++ei)
            os << get(name, source(*ei, G)) << " ";
        os << '\n';
    }
}

template < class IncidenceGraph, class Name >
void print_graph_dispatch(const IncidenceGraph& G, Name name, directed_tag,
    std::ostream& os = std::cout)
{
    typename graph_traits< IncidenceGraph >::vertex_iterator ui, ui_end;
    for (boost::tie(ui, ui_end) = vertices(G); ui != ui_end; ++ui)
    {
        os << get(name, *ui) << " --> ";
        typename graph_traits< IncidenceGraph >::out_edge_iterator ei, ei_end;
        for (boost::tie(ei, ei_end) = out_edges(*ui, G); ei != ei_end; ++ei)
            os << get(name, target(*ei, G)) << " ";
        os << '\n';
    }
}
template < class IncidenceGraph, class Name >
void print_graph_dispatch(const IncidenceGraph& G, Name name, undirected_tag,
    std::ostream& os = std::cout)
{
    typename graph_traits< IncidenceGraph >::vertex_iterator ui, ui_end;
    for (boost::tie(ui, ui_end) = vertices(G); ui != ui_end; ++ui)
    {
        os << get(name, *ui) << " <--> ";
        typename graph_traits< IncidenceGraph >::out_edge_iterator ei, ei_end;
        for (boost::tie(ei, ei_end) = out_edges(*ui, G); ei != ei_end; ++ei)
            os << get(name, target(*ei, G)) << " ";
        os << '\n';
    }
}
template < class IncidenceGraph, class Name >
void print_graph(
    const IncidenceGraph& G, Name name, std::ostream& os = std::cout)
{
    typedef typename graph_traits< IncidenceGraph >::directed_category Cat;
    print_graph_dispatch(G, name, Cat(), os);
}
template < class IncidenceGraph >
void print_graph(const IncidenceGraph& G, std::ostream& os = std::cout)
{
    print_graph(G, get(vertex_index, G), os);
}

template < class EdgeListGraph, class Name >
void print_edges(
    const EdgeListGraph& G, Name name, std::ostream& os = std::cout)
{
    typename graph_traits< EdgeListGraph >::edge_iterator ei, ei_end;
    for (boost::tie(ei, ei_end) = edges(G); ei != ei_end; ++ei)
        os << "(" << get(name, source(*ei, G)) << ","
           << get(name, target(*ei, G)) << ") ";
    os << '\n';
}

template < class EdgeListGraph, class VertexName, class EdgeName >
void print_edges2(const EdgeListGraph& G, VertexName vname, EdgeName ename,
    std::ostream& os = std::cout)
{
    typename graph_traits< EdgeListGraph >::edge_iterator ei, ei_end;
    for (boost::tie(ei, ei_end) = edges(G); ei != ei_end; ++ei)
        os << get(ename, *ei) << "(" << get(vname, source(*ei, G)) << ","
           << get(vname, target(*ei, G)) << ") ";
    os << '\n';
}

template < class VertexListGraph, class Name >
void print_vertices(
    const VertexListGraph& G, Name name, std::ostream& os = std::cout)
{
    typename graph_traits< VertexListGraph >::vertex_iterator vi, vi_end;
    for (boost::tie(vi, vi_end) = vertices(G); vi != vi_end; ++vi)
        os << get(name, *vi) << " ";
    os << '\n';
}

template < class Graph, class Vertex >
bool is_adj_dispatch(Graph& g, Vertex a, Vertex b, bidirectional_tag)
{
    typename graph_traits< Graph >::adjacency_iterator vi, viend, adj_found;
    boost::tie(vi, viend) = adjacent_vertices(a, g);
    adj_found = std::find(vi, viend, b);
    if (adj_found == viend)
        return false;

    typename graph_traits< Graph >::out_edge_iterator oi, oiend, out_found;
    boost::tie(oi, oiend) = out_edges(a, g);
    out_found = std::find_if(oi, oiend, incident_to(b, g));
    if (out_found == oiend)
        return false;

    typename graph_traits< Graph >::in_edge_iterator ii, iiend, in_found;
    boost::tie(ii, iiend) = in_edges(b, g);
    in_found = std::find_if(ii, iiend, incident_from(a, g));
    if (in_found == iiend)
        return false;

    return true;
}
template < class Graph, class Vertex >
bool is_adj_dispatch(Graph& g, Vertex a, Vertex b, directed_tag)
{
    typename graph_traits< Graph >::adjacency_iterator vi, viend, found;
    boost::tie(vi, viend) = adjacent_vertices(a, g);
    found = std::find(vi, viend, b);
    if (found == viend)
        return false;

    typename graph_traits< Graph >::out_edge_iterator oi, oiend, out_found;
    boost::tie(oi, oiend) = out_edges(a, g);

    out_found = std::find_if(oi, oiend, incident_to(b, g));
    if (out_found == oiend)
        return false;
    return true;
}
template < class Graph, class Vertex >
bool is_adj_dispatch(Graph& g, Vertex a, Vertex b, undirected_tag)
{
    return is_adj_dispatch(g, a, b, directed_tag());
}

template < class Graph, class Vertex >
bool is_adjacent(Graph& g, Vertex a, Vertex b)
{
    typedef typename graph_traits< Graph >::directed_category Cat;
    return is_adj_dispatch(g, a, b, Cat());
}

template < class Graph, class Edge > bool in_edge_set(Graph& g, Edge e)
{
    typename Graph::edge_iterator ei, ei_end, found;
    boost::tie(ei, ei_end) = edges(g);
    found = std::find(ei, ei_end, e);
    return found != ei_end;
}

template < class Graph, class Vertex > bool in_vertex_set(Graph& g, Vertex v)
{
    typename Graph::vertex_iterator vi, vi_end, found;
    boost::tie(vi, vi_end) = vertices(g);
    found = std::find(vi, vi_end, v);
    return found != vi_end;
}

template < class Graph, class Vertex >
bool in_edge_set(Graph& g, Vertex u, Vertex v)
{
    typename Graph::edge_iterator ei, ei_end;
    for (boost::tie(ei, ei_end) = edges(g); ei != ei_end; ++ei)
        if (source(*ei, g) == u && target(*ei, g) == v)
            return true;
    return false;
}

// is x a descendant of y?
template < typename ParentMap >
inline bool is_descendant(typename property_traits< ParentMap >::value_type x,
    typename property_traits< ParentMap >::value_type y, ParentMap parent)
{
    if (get(parent, x) == x) // x is the root of the tree
        return false;
    else if (get(parent, x) == y)
        return true;
    else
        return is_descendant(get(parent, x), y, parent);
}

// is y reachable from x?
template < typename IncidenceGraph, typename VertexColorMap >
inline bool is_reachable(
    typename graph_traits< IncidenceGraph >::vertex_descriptor x,
    typename graph_traits< IncidenceGraph >::vertex_descriptor y,
    const IncidenceGraph& g,
    VertexColorMap color) // should start out white for every vertex
{
    typedef typename property_traits< VertexColorMap >::value_type ColorValue;
    dfs_visitor<> vis;
    depth_first_visit(g, x, vis, color);
    return get(color, y) != color_traits< ColorValue >::white();
}

// Is the undirected graph connected?
// Is the directed graph strongly connected?
template < typename VertexListGraph, typename VertexColorMap >
inline bool is_connected(const VertexListGraph& g, VertexColorMap color)
{
    typedef typename property_traits< VertexColorMap >::value_type ColorValue;
    typedef color_traits< ColorValue > Color;
    typename graph_traits< VertexListGraph >::vertex_iterator ui, ui_end, vi,
        vi_end, ci, ci_end;
    for (boost::tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui)
        for (boost::tie(vi, vi_end) = vertices(g); vi != vi_end; ++vi)
            if (*ui != *vi)
            {
                for (boost::tie(ci, ci_end) = vertices(g); ci != ci_end; ++ci)
                    put(color, *ci, Color::white());
                if (!is_reachable(*ui, *vi, g, color))
                    return false;
            }
    return true;
}

template < typename Graph >
bool is_self_loop(
    typename graph_traits< Graph >::edge_descriptor e, const Graph& g)
{
    return source(e, g) == target(e, g);
}

template < class T1, class T2 >
std::pair< T1, T2 > make_list(const T1& t1, const T2& t2)
{
    return std::make_pair(t1, t2);
}

template < class T1, class T2, class T3 >
std::pair< T1, std::pair< T2, T3 > > make_list(
    const T1& t1, const T2& t2, const T3& t3)
{
    return std::make_pair(t1, std::make_pair(t2, t3));
}

template < class T1, class T2, class T3, class T4 >
std::pair< T1, std::pair< T2, std::pair< T3, T4 > > > make_list(
    const T1& t1, const T2& t2, const T3& t3, const T4& t4)
{
    return std::make_pair(t1, std::make_pair(t2, std::make_pair(t3, t4)));
}

template < class T1, class T2, class T3, class T4, class T5 >
std::pair< T1, std::pair< T2, std::pair< T3, std::pair< T4, T5 > > > >
make_list(const T1& t1, const T2& t2, const T3& t3, const T4& t4, const T5& t5)
{
    return std::make_pair(
        t1, std::make_pair(t2, std::make_pair(t3, std::make_pair(t4, t5))));
}

namespace graph
{

    // Functor for remove_parallel_edges: edge property of the removed edge is
    // added to the remaining
    template < typename EdgeProperty > struct add_removed_edge_property
    {
        add_removed_edge_property(EdgeProperty ep) : ep(ep) {}

        template < typename Edge > void operator()(Edge stay, Edge away)
        {
            put(ep, stay, get(ep, stay) + get(ep, away));
        }
        EdgeProperty ep;
    };

    // Same as above: edge property is capacity here
    template < typename Graph >
    struct add_removed_edge_capacity
    : add_removed_edge_property<
          typename property_map< Graph, edge_capacity_t >::type >
    {
        typedef add_removed_edge_property<
            typename property_map< Graph, edge_capacity_t >::type >
            base;
        add_removed_edge_capacity(Graph& g) : base(get(edge_capacity, g)) {}
    };

    template < typename Graph > bool has_no_vertices(const Graph& g)
    {
        typedef typename boost::graph_traits< Graph >::vertex_iterator vi;
        std::pair< vi, vi > p = vertices(g);
        return (p.first == p.second);
    }

    template < typename Graph > bool has_no_edges(const Graph& g)
    {
        typedef typename boost::graph_traits< Graph >::edge_iterator ei;
        std::pair< ei, ei > p = edges(g);
        return (p.first == p.second);
    }

    template < typename Graph >
    bool has_no_out_edges(
        const typename boost::graph_traits< Graph >::vertex_descriptor& v,
        const Graph& g)
    {
        typedef typename boost::graph_traits< Graph >::out_edge_iterator ei;
        std::pair< ei, ei > p = out_edges(v, g);
        return (p.first == p.second);
    }

} // namespace graph

#include <boost/graph/iteration_macros.hpp>

template < class PropertyIn, class PropertyOut, class Graph >
void copy_vertex_property(PropertyIn p_in, PropertyOut p_out, Graph& g)
{
    BGL_FORALL_VERTICES_T(u, g, Graph)
    put(p_out, u, get(p_in, g));
}

template < class PropertyIn, class PropertyOut, class Graph >
void copy_edge_property(PropertyIn p_in, PropertyOut p_out, Graph& g)
{
    BGL_FORALL_EDGES_T(e, g, Graph)
    put(p_out, e, get(p_in, g));
}

// Return true if property_map1 and property_map2 differ
// for any of the vertices in graph.
template < typename PropertyMapFirst, typename PropertyMapSecond,
    typename Graph >
bool are_property_maps_different(const PropertyMapFirst property_map1,
    const PropertyMapSecond property_map2, const Graph& graph)
{

    BGL_FORALL_VERTICES_T(vertex, graph, Graph)
    {
        if (get(property_map1, vertex) != get(property_map2, vertex))
        {

            return (true);
        }
    }

    return (false);
}

} /* namespace boost */

#endif /* BOOST_GRAPH_UTILITY_HPP*/