ahh now i see, because of the (shared) pointer to the priority_queue the forward declaration 'struct degree_compare;' works. This is really good to know. So this was my missing part. Thank you for your patience! On Wed, 2011-10-26 at 15:52 -0400, Jeremiah Willcock wrote:
On Wed, 26 Oct 2011, Christoph wrote:
i am sorry but i can't find the solution to my problem. I know how to use
boost::adjacency_list_traits<boost::listS, boost::vecS, boost::bidirectionalS>::vertex_descriptor
and
boost::adjacency_list_traits<boost::listS, boost::vecS, boost::bidirectionalS>::edge_descriptor
inside of bundled graph properties but i need the graph type itself to use 'vertex_degree (u, g)' in the comparison object given to a priority_queue inside of the graph_property struct (see first example).
Is having a shared_ptr (or scoped_ptr) to the priority_queue acceptable to have in your graph property? If so, I have it working:
// begin code
#include <iostream> #include <map> #include <queue> #include <boost/graph/adjacency_list.hpp> #include <boost/smart_ptr.hpp>
typedef boost::adjacency_list_traits<boost::listS, boost::vecS, boost::bidirectionalS> link_adjacency_list_traits;
struct vertex_properties; struct edge_properties; struct graph_properties;
struct vertex_properties { std::map <int, link_adjacency_list_traits::edge_descriptor > used_colors; // this one works fine, i can use a traits::edge_descriptor };
struct degree_compare;
struct graph_properties { int delta; boost::shared_ptr< std::priority_queue< link_adjacency_list_traits::vertex_descriptor, std::vector<link_adjacency_list_traits::vertex_descriptor>, degree_compare> > pq; // link_adjacency_list_traits::??? g; // i need a 'traits_graph', too // link_graph g; is not possible because its definition needs // the definition of graph_properties // how to declare it? // but out_degree (u, g) does not need to know any properties };
struct edge_properties { int color; };
typedef boost::adjacency_list < boost::listS, boost::listS, boost::bidirectionalS, vertex_properties, edge_properties, graph_properties> link_graph;
struct degree_compare { const link_graph& g; degree_compare(const link_graph& g): g(g) {} bool operator()(const boost::graph_traits<link_graph>::vertex_descriptor& a, const boost::graph_traits<link_graph>::vertex_descriptor& b) const { return out_degree(a, g) < out_degree(b, g); } };
int main () { link_graph g; }
// end code
-- Jeremiah Willcock _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users
-- Christoph <c_p@gmx-topmail.de>