Hi Bj�rn, On Mon, 15 Jul 2002, [iso-8859-1] Bj�rn Lindberg wrote: yg-boo> > 2. Use the traverse_tree function in boost/graph/tree_traits.hpp and yg-boo> > the graph_as_tree adaptor from boost/graph/graph_as_tree.hpp. Note yg-boo> > that these two files are undocumented and untested :( However, yg-boo> > if you find bugs I promise to fix them :) yg-boo> yg-boo> It looks to me like the second suggestion would be the simplest and most yg-boo> elegant solution. I have a couple of questions though, I can't get it to yg-boo> quite work. I think I'm misunderstanding the template parameters to the yg-boo> graph_as_tree class. What is ParentMap in this context? yg-boo> yg-boo> Let's say I have the following graph type: yg-boo> yg-boo> typedef boost::adjacency_list<boost::vecS, boost::vecS, yg-boo> boost::directedS, vertex_property, edge_property> tree; yg-boo> yg-boo> How would I make a graph_as_tree object out of such a graph for use with yg-boo> the traverse_tree function? The ParentMap maps a vertex to its parent vertex in the tree. So, for example, you could do the following: tree G; // fill G with vertices and edges ... typedef boost::adjacency_list_traits<boost::vecS, boost::vecS, boost::directedS>::vertex_descriptor vertex_t; std::vector<vertex_t> parent_vec(num_vertices(G)); typedef iterator_property_map<std::vector<vertex_t>::iterator> parent_map_t; parent_map_t parent_map(parent_vec.begin()); typedef graph_as_tree<tree, parent_map_t> real_tree_t; vertex_t root = *vertices(G).begin(); real_tree_t T(G, root, parent_map); The above call to the constructor for T fills in the parent map. One question... do you need to access parents? If not, you could fabricate a dummy property map of the right type and pass that in. Or you could hack graph_as_tree and remove all the stuff about parents. Cheers, Jeremy ---------------------------------------------------------------------- Jeremy Siek http://php.indiana.edu/~jsiek/ Ph.D. Student, Indiana Univ. B'ton email: jsiek@osl.iu.edu C++ Booster (http://www.boost.org) office phone: (812) 855-3608 ----------------------------------------------------------------------