Re: [Boost-users] Graph Library Question

Subject: Re: [Boost-users] Graph Library Question
From: alex (alexhighviz_at_[hidden])
Date: 2014-05-20 12:31:01

>I tried to implement the simplified code but I guess I really do not
understand
>the Boost Graph lib.
>

You might find it easier to use shared_array_property_maps (I do). Try if
the following works for you.

typedef typename boost::graph_traits<graph_t>::vertex_descriptor
vertex_type;
typedef typename boost::property_map<graph_t, vertex_index_t>::type
index_map_type;
typedef typename boost::shared_array_property_map<int, index_map_type >
distance_map_type;
typedef typename boost::shared_array_property_map<vertex_type,
index_map_type > predecessor_map_type;

vertex_type start = 24; // or whatever
vertex_type end = 13;  // or whatever

index_map_type vertex_id = get(vertex_index, g);
distance_map_type distance(boost::num_vertices(g), vertex_id);
predecessor_map_type predecessor(boost::num_vertices(g), vertex_id);

boost::dijkstra_shortest_paths(g, start,
boost::distance_map(distance).predecessor_map(predecessor)));

std::vector<vertex_type> path;
for(vertex_type current = end; current != start; current =
predecessor[current] )
{
  path.push_back(current);
}
path.push_back(start);
std::reverse(path.begin(), path.end());