Module org.jgrapht.core
Package org.jgrapht.alg.shortestpath

Class MartinShortestPath<V,E>

java.lang.Object
org.jgrapht.alg.shortestpath.MartinShortestPath<V,E>
Type Parameters:
V - the vertex type
E - the edge type
All Implemented Interfaces:
MultiObjectiveShortestPathAlgorithm<V,E>
public class MartinShortestPath<V,E> extends Object
Martin's algorithm for the multi-objective shortest paths problem.

Martin's label setting algorithm is a multiple objective extension of Dijkstra's algorithm, where the minimum operator is replaced by a dominance test. It computes a maximal complete set of efficient paths when all the cost values are non-negative.

Note that the multi-objective shortest path problem is a well-known NP-hard problem.

Author:
Dimitrios Michail

  • Field Details

    • graph

      protected final Graph<V,E> graph
      The underlying graph.

  • Constructor Details

    • MartinShortestPath

      public MartinShortestPath(Graph<V,E> graph, Function<E,double[]> edgeWeightFunction)
      Create a new shortest path algorithm
      Parameters:
      graph - the input graph
      edgeWeightFunction - the edge weight function

  • Method Details

    • getPaths

      public List<GraphPath<V,E>> getPaths(V source, V sink)
      Description copied from interface: MultiObjectiveShortestPathAlgorithm
      Get a shortest path from a source vertex to a sink vertex.
      Parameters:
      source - the source vertex
      sink - the target vertex
      Returns:
      a shortest path or null if no path exists

    • getPaths

      public MultiObjectiveShortestPathAlgorithm.MultiObjectiveSingleSourcePaths<V,E> getPaths(V source)
      Description copied from interface: MultiObjectiveShortestPathAlgorithm
      Compute all shortest paths starting from a single source vertex.
      Specified by:
      getPaths in interface MultiObjectiveShortestPathAlgorithm<V,E>
      Parameters:
      source - the source vertex
      Returns:
      the shortest paths

    • createEmptyPath

      protected final GraphPath<V,E> createEmptyPath(V source, V sink)
      Create an empty path. Returns null if the source vertex is different than the target vertex.
      Parameters:
      source - the source vertex
      sink - the sink vertex
      Returns:
      an empty path or null null if the source vertex is different than the target vertex

    • validateEdgeWeightFunction

      protected int validateEdgeWeightFunction(Function<E,double[]> edgeWeightFunction)
      Check the validity of an edge weight function. The function must return a non-null vector of non-negative values of the same length for every edge of the graph.
      Parameters:
      edgeWeightFunction - the edge weight function
      Returns:
      the number of dimensions