Thanks for your reply. I am still learning the library so I don't know the source very well. How would one provide new functions to DSP? Is there some sort of internal mechanism to allow for this?
Sorry... I was in a hurry when I wrote last. The DSP algorithm takes function objects as parameters that can be used to change the default behavior of distance comparison and combination. It's mentioned here, but I doubt that there are any good examples. http://www.boost.org/doc/libs/1_38_0/libs/graph/doc/dijkstra_shortest_paths.... For example, you might call it as: dijkstra_shortest_paths(g, v, weight_map(weights). distance_map(results). distance_compare(my_compare)); Where my_compare is a BinaryPredicate (like std::less), taking the value_type of the weights. You might also look at ways using or modifying the color_map, which is also an optional parameter. Hope that's more clear. Andrew Sutton andrew.n.sutton@gmail.com