Try to use GraphAlgoFactory#dijkstra instead. 2011/11/14 Joel Cordeiro <jkorde...@gmail.com>
> Hi there, > > I'm having performance issues with Neo4J while using GraphAlgoFactory to > find a path between two nodes. I want to calculate the cost between the two > nodes (each relation type has a different cost), with the maximum depth of > 3 (paths with more length can be discarded). I'm using the findAllPaths > method, since the findShorthestPath method takes into account the path > length and not the cost associated to it. But this is not the ideal > solution, because of the performance issues I'm having. > > I'm thinking about using something like the Dijkstra algorithm, but with a > maximum depth of 3. I already took a look at the Neo4J source code and > found the class *org.neo4j.graphalgo.impl.shortestpath.Dijkstra, *which I > have tried to use with limitMaxRelationShipsToTraverse set to 3. Most of > the times it doesn't found any path, and throws the exception: > java.lang.RuntimeException: Trying to decrease to a greater key > at > > org.neo4j.graphalgo.impl.util.FibonacciHeap.decreaseKey(FibonacciHeap.java:318) > at > > org.neo4j.graphalgo.impl.shortestpath.DijkstraPriorityQueueFibonacciImpl.decreaseValue(DijkstraPriorityQueueFibonacciImpl.java:103) > at > > org.neo4j.graphalgo.impl.shortestpath.Dijkstra$DijstraIterator.next(Dijkstra.java:393) > at > org.neo4j.graphalgo.impl.shortestpath.Dijkstra.calculate(Dijkstra.java:516) > > Is this class appropriate for what I want to accomplish? I also would like > to know if this is a good solution for the discribed problem, or if there > is a better solution out there. > > Best regards, > Joel Filipe Antunes Cordeiro > jkorde...@gmail.com > j...@student.dei.uc.pt > _______________________________________________ > Neo4j mailing list > User@lists.neo4j.org > https://lists.neo4j.org/mailman/listinfo/user > -- Mattias Persson, [matt...@neotechnology.com] Hacker, Neo Technology www.neotechnology.com _______________________________________________ Neo4j mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user
