예제 #1
0
  public Set<Cloudlet> allCloudletLinked(Cloudlet cloudlet) {
    Set<Cloudlet> set = new HashSet<Cloudlet>();

    // adds all the cloudlets in the same vertex
    ApplicationVertex av = this.getVertexForCloudlet(cloudlet);
    set.addAll(av.getCloudlets());

    // adds the cloudlets from the connected vertex
    for (ApplicationEdge ae : graph.edgesOf(av)) {
      ApplicationVertex source = graph.getEdgeSource(ae);
      if (source.equals(av) == false) set.addAll(source.getCloudlets());

      ApplicationVertex target = graph.getEdgeTarget(ae);
      if (target.equals(av) == false) set.addAll(source.getCloudlets());
    }

    return set;
  }
예제 #2
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  // Calculate the contribution of current vertex's shortest-path graph to final edge betweenness
  // (Newman algorithm)
  // M. E. J. Newman and M. Girvan, Finding and evaluating community structure in networks, Physical
  // Review E69, 026113 (2004)
  private SimpleWeightedGraph<String, DefaultWeightedEdge> NewmanAlgorithm(
      Multigraph<String, DefaultEdge> shortestPathGraph, String thisVertex) {

    if (shortestPathGraph.edgeSet().size() == 0) // No outer degree
    return null;

    // 1. Initialize the edge betweenness digraph
    SimpleWeightedGraph<String, DefaultWeightedEdge> edgeBetweennessDigraph =
        new SimpleWeightedGraph<String, DefaultWeightedEdge>(DefaultWeightedEdge.class);
    // Add vertices
    for (String curVertex : shortestPathGraph.vertexSet())
      edgeBetweennessDigraph.addVertex(curVertex);

    // 2. Deal with corresponding edges
    // 2.1. Calculate vertex distance and weight
    // 2.1.1. Initialize related variables
    HashMap<String, Integer> mapVertexDistance = new HashMap<String, Integer>(); // Vertex distance
    for (String curVertex : shortestPathGraph.vertexSet()) mapVertexDistance.put(curVertex, 0);
    HashMap<String, Double> mapVertexWeight = new HashMap<String, Double>(); // Vertex weight
    for (String curVertex : shortestPathGraph.vertexSet()) mapVertexWeight.put(curVertex, 1.0);
    Queue<String> verticesQueue = new LinkedList<String>(); // Store the queue of operated vertices
    // 2.1.2. Traverse the shortest-path digraph, get corresponding vertex distance and weight
    verticesQueue.add(thisVertex);
    String currentVertex = thisVertex;
    while (!verticesQueue.isEmpty()) {
      // 2.1.2.1. Read the bottom vertex in the queue, deal with all adjacent edges
      for (DefaultEdge curEdge : shortestPathGraph.edgesOf(currentVertex)) {
        String targetVertex = shortestPathGraph.getEdgeTarget(curEdge);
        if (mapVertexDistance.get(targetVertex)
            == 0) { // Target vertex value hasn't been evaluated yet
          mapVertexDistance.put(targetVertex, mapVertexDistance.get(currentVertex) + 1);
          mapVertexWeight.put(targetVertex, mapVertexWeight.get(currentVertex));
          verticesQueue.add(targetVertex);
        }
        // Target vertex value has already been set to source vertex distance plus 1
        else if (mapVertexDistance.get(targetVertex) == (mapVertexDistance.get(currentVertex) + 1))
          mapVertexWeight.put(
              targetVertex, mapVertexWeight.get(targetVertex) + mapVertexWeight.get(currentVertex));
      }
      // 2.1.2.2. All adjacent edges have been treated, remove the bottom element
      verticesQueue.remove();
      currentVertex = verticesQueue.peek();
    }

    // 2.2. Calculate the contribution of every edges to the edge betweenness
    // 2.2.1. Sort the vertices descendingly by the distance to the first vertex
    List<Map.Entry<String, Integer>> listVertexDistance =
        new ArrayList<Map.Entry<String, Integer>>(mapVertexDistance.entrySet());
    Collections.sort(
        listVertexDistance,
        new Comparator<Map.Entry<String, Integer>>() { // Sorting the list descendingly

          @Override
          public int compare(Entry<String, Integer> o1, Entry<String, Integer> o2) {
            return (o2.getValue().compareTo(o1.getValue()));
          }
        });
    // 2.2.2. Traverse the shortest-path digraph with the sorted vertices list
    for (Map.Entry<String, Integer> thisVertexDistance : listVertexDistance) {
      currentVertex = thisVertexDistance.getKey();
      for (DefaultEdge curEdge : shortestPathGraph.edgesOf(currentVertex)) {
        // 2.2.2.1. Get the source vertex
        String sourceVertex = shortestPathGraph.getEdgeSource(curEdge);
        String targetVertex = shortestPathGraph.getEdgeTarget(curEdge);
        String anotherVertex = "";
        if (currentVertex.equals(sourceVertex)) anotherVertex = targetVertex;
        else if (currentVertex.equals(targetVertex)) anotherVertex = sourceVertex;
        // 2.2.2.2. Calculate the value of the sum of all adjacent edges plus 1
        double totalSubWeights = 1.0;
        for (DefaultWeightedEdge curSubEdge : edgeBetweennessDigraph.edgesOf(currentVertex))
          totalSubWeights += edgeBetweennessDigraph.getEdgeWeight(curSubEdge);
        // 2.2.2.3. The new edge weight is calculated as totalSubWeights * (the quotient of the
        // weights of the two terminals)
        double wi = mapVertexWeight.get(anotherVertex);
        double wj = mapVertexWeight.get(currentVertex);
        totalSubWeights /= wi / wj;
        // 2.2.2.4. Add new edge with correct weight into the edge betweenness digraph
        DefaultWeightedEdge newEdge = new DefaultWeightedEdge();
        edgeBetweennessDigraph.addEdge(anotherVertex, currentVertex, newEdge);
        edgeBetweennessDigraph.setEdgeWeight(newEdge, totalSubWeights);
      }
    }

    return edgeBetweennessDigraph;
  }