Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

boost/graph/matrix_as_graph.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_MATRIX2GRAPH_HPP
#define BOOST_GRAPH_MATRIX2GRAPH_HPP

#include <utility>
#include <cstddef>
#include <iterator>
#include <boost/config.hpp>
#include <boost/operators.hpp>
#include <boost/pending/detail/int_iterator.hpp>
#include <boost/graph/graph_traits.hpp>

namespace boost
{

template < class Iter, class Vertex > class matrix_adj_iterator;

template < class Iter, class Vertex > class matrix_incidence_iterator;

}

#define BOOST_GRAPH_ADAPT_MATRIX_TO_GRAPH(Matrix)                             \
    namespace boost                                                           \
    {                                                                         \
        template <> struct graph_traits< Matrix >                             \
        {                                                                     \
            typedef Matrix::OneD::const_iterator Iter;                        \
            typedef Matrix::size_type V;                                      \
            typedef V vertex_descriptor;                                      \
            typedef Iter E;                                                   \
            typedef E edge_descriptor;                                        \
            typedef boost::matrix_incidence_iterator< Iter, V >               \
                out_edge_iterator;                                            \
            typedef boost::matrix_adj_iterator< Iter, V > adjacency_iterator; \
            typedef Matrix::size_type size_type;                              \
            typedef boost::int_iterator< size_type > vertex_iterator;         \
                                                                              \
            friend std::pair< vertex_iterator, vertex_iterator > vertices(    \
                const Matrix& g)                                              \
            {                                                                 \
                typedef vertex_iterator VIter;                                \
                return std::make_pair(VIter(0), VIter(g.nrows()));            \
            }                                                                 \
                                                                              \
            friend std::pair< out_edge_iterator, out_edge_iterator >          \
            out_edges(V v, const Matrix& g)                                   \
            {                                                                 \
                typedef out_edge_iterator IncIter;                            \
                return std::make_pair(                                        \
                    IncIter(g[v].begin()), IncIter(g[v].end()));              \
            }                                                                 \
            friend std::pair< adjacency_iterator, adjacency_iterator >        \
            adjacent_vertices(V v, const Matrix& g)                           \
            {                                                                 \
                typedef adjacency_iterator AdjIter;                           \
                return std::make_pair(                                        \
                    AdjIter(g[v].begin()), AdjIter(g[v].end()));              \
            }                                                                 \
            friend vertex_descriptor source(E e, const Matrix& g)             \
            {                                                                 \
                return e.row();                                               \
            }                                                                 \
            friend vertex_descriptor target(E e, const Matrix& g)             \
            {                                                                 \
                return e.column();                                            \
            }                                                                 \
            friend size_type num_vertices(const Matrix& g)                    \
            {                                                                 \
                return g.nrows();                                             \
            }                                                                 \
            friend size_type num_edges(const Matrix& g) { return g.nnz(); }   \
            friend size_type out_degree(V i, const Matrix& g)                 \
            {                                                                 \
                return g[i].nnz();                                            \
            }                                                                 \
        };                                                                    \
    }

namespace boost
{

template < class Iter, class Vertex > class matrix_adj_iterator
{
    typedef matrix_adj_iterator self;

public:
    typedef std::input_iterator_tag iterator_category;
    typedef Vertex value_type;
    typedef std::ptrdiff_t difference_type;
    typedef Vertex* pointer;
    typedef Vertex& reference;
    matrix_adj_iterator() {}
    matrix_adj_iterator(Iter i) : _iter(i) {}
    matrix_adj_iterator(const self& x) : _iter(x._iter) {}
    self& operator=(const self& x)
    {
        _iter = x._iter;
        return *this;
    }
    Vertex operator*() { return _iter.column(); }
    self& operator++()
    {
        ++_iter;
        return *this;
    }
    self operator++(int)
    {
        self t = *this;
        ++_iter;
        return t;
    }
    bool operator==(const self& x) const { return _iter == x._iter; }
    bool operator!=(const self& x) const { return _iter != x._iter; }

protected:
    Iter _iter;
};

template < class Iter, class Vertex > class matrix_incidence_iterator
{
    typedef matrix_incidence_iterator self;

public:
    typedef std::input_iterator_tag iterator_category;
    typedef Iter value_type;
    typedef std::ptrdiff_t difference_type;
    typedef Iter* pointer;
    typedef Iter& reference;
    matrix_incidence_iterator() {}
    matrix_incidence_iterator(Iter i) : _iter(i) {}
    matrix_incidence_iterator(const self& x) : _iter(x._iter) {}
    self& operator=(const self& x)
    {
        _iter = x._iter;
        return *this;
    }
    Iter operator*() { return _iter; }
    self& operator++()
    {
        ++_iter;
        return *this;
    }
    self operator++(int)
    {
        self t = *this;
        ++_iter;
        return t;
    }
    bool operator==(const self& x) const { return _iter == x._iter; }
    bool operator!=(const self& x) const { return _iter != x._iter; }

protected:
    Iter _iter;
};

} /* namespace boost */

#endif /* BOOST_GRAPH_MATRIX2GRAPH_HPP*/