Hi I am trying to graph-tool solve specific path finding problems. I have been using NetworkX in past but found it too slow and read good thing about graph-tool's speed. Basically I have 2 million + vertices and I want to find best path between 2 points (considering their weight and travel time i.e. cost). Now Im really interested in astar I can't seem to get it work for some reason. So in my scenario Im trying to do this: from graph_tool.all import * g = Graph() v0 = g.add_vertex() v1 = g.add_vertex() v2 = g.add_vertex() v3 = g.add_vertex() v4 = g.add_vertex() weight = g.new_edge_property("double") e_1_2 = g.add_edge(v1,v2) weight[e_1_2] = 1000 e_1_3 = g.add_edge(v1,v3) weight[e_1_3] = 100 e_3_4 = g.add_edge(v3,v4) weight[e_3_4] = 200 e_4_2 = g.add_edge(v4,v2) weight[e_4_2] = 40 class VisitorExample(graph_tool.search.AStarVisitor): def __init__(self, touched_v, touched_e, target): self.touched_v = touched_v self.touched_e = touched_e self.target = target def discover_vertex(self, u): self.touched_v[u] = True def examine_edge(self, e): self.touched_e[e] = True def edge_relaxed(self, e): if e.target() == self.target: raise gt.StopSearch() touch_v = g.new_vertex_property("bool") touch_e = g.new_edge_property("bool") target = v2 gt = graph_tool.search time = g.new_vertex_property("int") pred = g.new_vertex_property("int") dist, pred = gt.astar_search(g, v1, weight, VisitorExample(touch_v, touch_e, target), heuristic=lambda v: 1) Now I would "astar" to consider weights and choose the best path based on weight. For example weight for edge (1 & 2) = 1000, so travel from 1 -> 2 I would like to get a path 1 -> 3 -> 4 > 2 because combined weight of this is still less than that of 1 -> 2. But when I get the results it only gives edge 1 & 2 and wouldn't consider the above path. Could you also shed some light on setting up heuristics and costing functions for the above scenario. Thank you. -- View this message in context: http://main-discussion-list-for-the-graph-tool-project.982480.n3.nabble.com/... Sent from the Main discussion list for the graph-tool project mailing list archive at Nabble.com.