Hi, I'm fairly new to BGL so this may not be a bug after all......but I get a fair number of warnings about possible loss of data due to conversions (mainly between signed/unsigned types) with MSVC7 trying to compile the example below. Some may be ignored but at least line 188 of minimum_degree_ordering.hpp seems wrong: data[id[i]] = - (id[j] + offset); id[j] is unsigned, making (id[j] + offset) unsigned thus making the unary minus rather spurious. Also, compile time checks for correctly using signed types for the permutations would be nice :-) rgds Jeppe #include <iostream> #include <boost/graph/adjacency_list.hpp> #include "boost/graph/minimum_degree_ordering.hpp" #include <iostream> #include <boost/graph/adjacency_list.hpp> #include "boost/graph/minimum_degree_ordering.hpp" using namespace std; using namespace boost; int main(int, char **) { typedef adjacency_list <vecS, vecS, directedS> Graph; Graph G; add_edge(0, 1, G); add_edge(1, 0, G); add_edge(0, 2, G); add_edge(2, 0, G); add_edge(0, 5, G); add_edge(5, 0, G); add_edge(1, 2, G); add_edge(2, 1, G); add_edge(1, 3, G); add_edge(3, 1, G); add_edge(1, 6, G); add_edge(6, 1, G); add_edge(2, 4, G); add_edge(4, 2, G); add_edge(3, 4, G); add_edge(4, 3, G); add_edge(4, 5, G); add_edge(5, 4, G); std::vector<size_t> degree(num_vertices(G), 0); std::vector<int> inverse_perm(num_vertices(G), 0), perm(num_vertices(G), 0); std::vector<size_t> supernode_sizes(num_vertices(G), 1); property_map<Graph, vertex_index_t>::type id = get(vertex_index, G); minimum_degree_ordering (G, make_iterator_property_map(°ree[0], id, degree[0]), &inverse_perm[0], &perm[0], make_iterator_property_map(&supernode_sizes[0], id, supernode_sizes[0]), 0, id); for(size_t i = 0; i < num_vertices(G); ++i) std::cout << inverse_perm[i] << "\n"; return 0; }