On Nov 15, 2005, at 12:53 PM, Daniel Mitchell wrote:
I work with very large implicit graphs that use out-of-core storage for properties, including the vertex color property,
Very cool.
but the following bit of code in dijkstra_shortest_paths_no_init (boost-1.33.0) seems to preclude the use of a custom color map.
std::vector<default_color_type> color(num_vertices(g)); default_color_type c = white_color; breadth_first_visit(g, s, Q, bfs_vis, make_iterator_property_map(&color[0], index_map, c));
What is the rationale for the above code, and how should I work around it?
Well, I'd say that's a bug in dijkstra_shortest_paths_no_init, which should have a ColorMap template parameter. The best way to fix this would be to add a ColorMap parameter at the end, e.g., to turn dijkstra_shortest_paths_no_init into: template <class VertexListGraph, class DijkstraVisitor, class PredecessorMap, class DistanceMap, class WeightMap, class IndexMap, class Compare, class Combine, class DistZero, class ColorMap> inline void dijkstra_shortest_paths_no_init (const VertexListGraph& g, typename graph_traits<VertexListGraph>::vertex_descriptor s, PredecessorMap predecessor, DistanceMap distance, WeightMap weight, IndexMap index_map, Compare compare, Combine combine, DistZero zero, DijkstraVisitor vis, ColorMap color); Then just pass that color map through to the underlying breadth_first_search. For backward compatibility reasons, one would provide a helper function with the old signature that creates that iterator_property_map and forwards to the new, more-parameterized version. If you happen to make this change, I was greatly appreciate it if you would send it to the list so that we can incorporate it in future versions of the library. If we're quick, we can even get it into the upcoming 1.33.1 bug-fix release. Doug