Commit bf174831 authored by Tiago Peixoto's avatar Tiago Peixoto
Browse files

shortest_distance(): Remove redundant initializations

parent 2c7cab20

src/graph/topology/graph_distance.cc

+84 −76
Original line number Diff line number Diff line
@@ -47,16 +47,14 @@ public: 
        : _dist_map(dist_map), _pred(pred), _max_dist(max_dist),

          _source(source), _target(target), _dist(0) {}



    template <class Graph>

    void initialize_vertex(typename graph_traits<Graph>::vertex_descriptor v,

                           Graph&)

    ~bfs_max_visitor()

    {

        typedef typename property_traits<DistMap>::value_type dist_t;

        dist_t inf = std::is_floating_point<dist_t>::value ?

        constexpr dist_t inf = std::is_floating_point<dist_t>::value ?

            numeric_limits<dist_t>::infinity() :

            numeric_limits<dist_t>::max();

        _dist_map[v] = (v == _source) ? 0 : inf;

        _pred[v] = v;

        for (auto v : _unreached)

            _dist_map[v] = inf;

    }



    template <class Graph>
@@ -70,8 +68,7 @@ public: 
    void examine_vertex(typename graph_traits<Graph>::vertex_descriptor v,

                        Graph&)

    {

        typedef typename property_traits<DistMap>::value_type val_t;

        if ( _dist_map[v] > val_t(_max_dist))

        if ( _dist_map[v] > _max_dist)

            throw stop_search();

    }
@@ -79,9 +76,12 @@ public: 
    void discover_vertex(typename graph_traits<Graph>::vertex_descriptor v,

                         Graph&)

    {

        if (size_t(_pred[v]) == v)

        auto p = _pred[v];

        if (size_t(p) == v)

            return;

        _dist_map[v] = _dist_map[_pred[v]] + 1;

        _dist_map[v] = _dist_map[p] + 1;

        if (_dist_map[v] > _max_dist)

            _unreached.push_back(v);

        if (v == _target)

            throw stop_search();

    }
@@ -89,10 +89,11 @@ public: 
private:

    DistMap _dist_map;

    PredMap _pred;

    size_t _max_dist;

    typename property_traits<DistMap>::value_type _max_dist;

    size_t _source;

    size_t _target;

    size_t _dist;

    std::vector<size_t> _unreached;

};



template <class DistMap, class PredMap>
@@ -106,16 +107,14 @@ public: 
        : _dist_map(dist_map), _pred(pred), _max_dist(max_dist),

          _source(source), _target(target), _dist(0) {}



    template <class Graph>

    void initialize_vertex(typename graph_traits<Graph>::vertex_descriptor v,

                           Graph&)

    ~bfs_max_multiple_targets_visitor()

    {

        typedef typename property_traits<DistMap>::value_type dist_t;

        dist_t inf = std::is_floating_point<dist_t>::value ?

        constexpr dist_t inf = std::is_floating_point<dist_t>::value ?

            numeric_limits<dist_t>::infinity() :

            numeric_limits<dist_t>::max();

        _dist_map[v] = (v == _source) ? 0 : inf;

        _pred[v] = v;

        for (auto v : _unreached)

            _dist_map[v] = inf;

    }



    template <class Graph>
@@ -129,8 +128,7 @@ public: 
    void examine_vertex(typename graph_traits<Graph>::vertex_descriptor v,

                        Graph&)

    {

        typedef typename property_traits<DistMap>::value_type val_t;

        if ( _dist_map[v] > val_t(_max_dist))

        if ( _dist_map[v] > _max_dist)

            throw stop_search();

    }
@@ -138,9 +136,13 @@ public: 
    void discover_vertex(typename graph_traits<Graph>::vertex_descriptor v,

                         Graph&)

    {

        if (size_t(_pred[v]) == v)

        auto p = _pred[v];

        if (size_t(p) == v)

            return;

        _dist_map[v] = _dist_map[_pred[v]] + 1;

        _dist_map[v] = _dist_map[p] + 1;



        if (_dist_map[v] > _max_dist)

            _unreached.push_back(v);



        auto iter = _target.find(v);

        if (iter != _target.end())
@@ -154,10 +156,11 @@ public: 
private:

    DistMap _dist_map;

    PredMap _pred;

    size_t _max_dist;

    typename property_traits<DistMap>::value_type _max_dist;

    size_t _source;

    gt_hash_set<std::size_t> _target;

    size_t _dist;

    std::vector<size_t> _unreached;

};
@@ -168,9 +171,16 @@ class djk_max_visitor: 
public:

    djk_max_visitor(DistMap dist_map,

                    typename property_traits<DistMap>::value_type max_dist,

                    typename property_traits<DistMap>::value_type inf,

                    size_t target)

        : _dist_map(dist_map), _max_dist(max_dist), _target(target) {}

        : _dist_map(dist_map), _max_dist(max_dist), _inf(inf),

          _target(target) {}



    ~djk_max_visitor()

    {

        for (auto v : _unreached)

            _dist_map[v] = _inf;

    }



    template <class Graph>

    void examine_vertex(typename graph_traits<Graph>::vertex_descriptor u,
@@ -183,11 +193,20 @@ public: 
            throw stop_search();

    }



    template <class Graph>

    void discover_vertex(typename graph_traits<Graph>::vertex_descriptor u,

                         Graph&)

    {

        if (_dist_map[u] > _max_dist)

            _unreached.push_back(u);

    }



private:

    DistMap _dist_map;

    typename property_traits<DistMap>::value_type _max_dist;

    typename property_traits<DistMap>::value_type _inf;

    size_t _target;

    std::vector<size_t> _unreached;

};
@@ -198,9 +217,16 @@ class djk_max_multiple_targets_visitor: 
public:

    djk_max_multiple_targets_visitor(DistMap dist_map,

                                     typename property_traits<DistMap>::value_type max_dist, 

                                     typename property_traits<DistMap>::value_type inf, 

                                     gt_hash_set<std::size_t> target)

        : _dist_map(dist_map), _max_dist(max_dist), _target(target) {}

        : _dist_map(dist_map), _max_dist(max_dist), _inf(inf),

          _target(target) {}



    ~djk_max_multiple_targets_visitor()

    {

        for (auto v : _unreached)

            _dist_map[v] = _inf;

    }



    template <class Graph>

    void examine_vertex(typename graph_traits<Graph>::vertex_descriptor u,
@@ -218,11 +244,20 @@ public: 
        };

    }



    template <class Graph>

    void discover_vertex(typename graph_traits<Graph>::vertex_descriptor u,

                         Graph&)

    {

        if (_dist_map[u] > _max_dist)

            _unreached.push_back(u);

    }



private:

    DistMap _dist_map;

    typename property_traits<DistMap>::value_type _max_dist;

    typename property_traits<DistMap>::value_type _inf;

    gt_hash_set<std::size_t> _target;

    std::vector<size_t> _unreached;

};



struct do_bfs_search
@@ -245,6 +280,8 @@ struct do_bfs_search 


        dist_t max_d = (max_dist > 0) ? max_dist : inf;



        dist_map[source] = 0;



        unchecked_vector_property_map<boost::default_color_type, VertexIndexMap>

        color_map(vertex_index, num_vertices(g));

        try
@@ -254,7 +291,7 @@ struct do_bfs_search 
                size_t target = tgt.empty() ?

                    graph_traits<GraphInterface::multigraph_t>::null_vertex() :

                    *tgt.begin();

                breadth_first_search(g, vertex(source, g),

                breadth_first_visit(g, vertex(source, g),

                                    visitor(bfs_max_visitor<DistMap, PredMap>

                                            (dist_map, pred_map, max_d,

                                             source, target)).
@@ -263,7 +300,7 @@ struct do_bfs_search 
            }

            else

            {

                breadth_first_search(g, vertex(source, g),

                breadth_first_visit(g, vertex(source, g),

                                    visitor(bfs_max_multiple_targets_visitor<DistMap, PredMap>

                                            (dist_map, pred_map, max_d,

                                             source, tgt)).
@@ -273,17 +310,6 @@ struct do_bfs_search 


        }

        catch (stop_search&) {}



        if (max_dist > 0)

        {

            parallel_vertex_loop(g,

                                 [&](auto v)

                                 {

                                     auto& d = dist_map[v];

                                     if (d > max_dist)

                                         d = inf;

                                 });

        }

    }

};
@@ -309,7 +335,6 @@ struct do_djk_search 
        gt_hash_set<std::size_t> tgt(target_list.begin(),

                                     target_list.end());



        parallel_vertex_loop(g, [&](auto v) { dist_map[v] = inf; });

        dist_map[source] = 0;



        try
@@ -319,42 +344,25 @@ struct do_djk_search 
                size_t target = tgt.empty() ?

                    graph_traits<GraphInterface::multigraph_t>::null_vertex() :

                    *tgt.begin();

                dijkstra_shortest_paths_no_color_map

                    (g, vertex(source, g),

                     weight_map(weight).

                     distance_map(dist_map).

                     vertex_index_map(vertex_index).

                     predecessor_map(pred_map).

                     distance_inf(inf).

                     visitor(djk_max_visitor<DistMap>

                             (dist_map, max_d, target)));

                dijkstra_shortest_paths_no_color_map_no_init

                    (g, vertex(source, g), pred_map, dist_map, weight,

                     vertex_index, std::less<dist_t>(),

                     boost::closed_plus<dist_t>(), inf, dist_t(),

                     djk_max_visitor<DistMap>(dist_map, max_d, inf, target));

            }

            else

            {

                dijkstra_shortest_paths_no_color_map

                    (g, vertex(source, g),

                     weight_map(weight).

                     distance_map(dist_map).

                     vertex_index_map(vertex_index).

                     predecessor_map(pred_map).

                     distance_inf(inf).

                     visitor(djk_max_multiple_targets_visitor<DistMap>

                             (dist_map, max_d, tgt)));

                dijkstra_shortest_paths_no_color_map_no_init

                    (g, vertex(source, g), pred_map, dist_map, weight,

                     vertex_index, std::less<dist_t>(),

                     boost::closed_plus<dist_t>(), inf, dist_t(),

                     djk_max_multiple_targets_visitor<DistMap>(dist_map, max_d,

                                                               inf, tgt));

            }



        }

        catch (stop_search&) {}



        if (max_dist > 0)

        {

            parallel_vertex_loop(g,

                                 [&](auto v)

                                 {

                                     auto& d = dist_map[v];

                                     if (d > max_dist)

                                         d = inf;

                                 });

        }

    }

};

src/graph_tool/topology/__init__.py

+5 −1
Original line number Diff line number Diff line
@@ -1671,7 +1671,11 @@ def shortest_distance(g, source=None, target=None, weights=None, 
        u = g



    if source is not None:

        pmap = g.copy_property(u.vertex_index, value_type="int64_t")

        if numpy.issubdtype(dist_map.a.dtype, numpy.integer):

            dist_map.fa = numpy.iinfo(dist_map.a.dtype).max

        else:

            dist_map.fa = numpy.inf

        pmap = u.copy_property(u.vertex_index, value_type="int64_t")

        libgraph_tool_topology.get_dists(u._Graph__graph,

                                         int(source),

                                         target,