Exemplo n.º 1
0
  private double scoreGraphChange(Node y, Set<Node> parents1, Set<Node> parents2) {
    int yIndex = hashIndices.get(y);

    double score1, score2;

    int[] parentIndices1 = new int[parents1.size()];

    int count = -1;
    for (Node parent : parents1) {
      parentIndices1[++count] = hashIndices.get(parent);
    }

    if (isDiscrete()) {
      score1 = localDiscreteScore(yIndex, parentIndices1);
    } else {
      score1 = localSemScore(yIndex, parentIndices1);
    }

    int[] parentIndices2 = new int[parents2.size()];

    int count2 = -1;
    for (Node parent : parents2) {
      parentIndices2[++count2] = hashIndices.get(parent);
    }

    if (isDiscrete()) {
      score2 = localDiscreteScore(yIndex, parentIndices2);
    } else {
      score2 = localSemScore(yIndex, parentIndices2);
    }

    return score1 - score2;
  }
Exemplo n.º 2
0
  // ===========================SCORING METHODS===================//
  public double scoreDag(Graph graph) {
    Graph dag = new EdgeListGraphSingleConnections(graph);
    buildIndexing(graph);

    double score = 0.0;

    for (Node y : dag.getNodes()) {
      Set<Node> parents = new HashSet<Node>(dag.getParents(y));
      int nextIndex = -1;
      for (int i = 0; i < getVariables().size(); i++) {
        nextIndex = hashIndices.get(variables.get(i));
      }
      int parentIndices[] = new int[parents.size()];
      Iterator<Node> pi = parents.iterator();
      int count = 0;
      while (pi.hasNext()) {
        Node nextParent = pi.next();
        parentIndices[count++] = hashIndices.get(nextParent);
      }

      if (this.isDiscrete()) {
        score += localDiscreteScore(nextIndex, parentIndices);
      } else {
        score += localSemScore(nextIndex, parentIndices);
      }
    }
    return score;
  }
Exemplo n.º 3
0
  private boolean existsUnblockedSemiDirectedPath(Node from, Node to, List<Node> cond, Graph G) {
    Queue<Node> Q = new LinkedList<Node>();
    Set<Node> V = new HashSet<Node>();
    Q.offer(from);
    V.add(from);

    while (!Q.isEmpty()) {
      Node t = Q.remove();
      if (t == to) return true;

      for (Node u : G.getAdjacentNodes(t)) {
        Edge edge = G.getEdge(t, u);
        Node c = Edges.traverseSemiDirected(t, edge);
        if (c == null) continue;
        if (cond.contains(c)) continue;
        if (c == to) return true;

        if (!V.contains(c)) {
          V.add(c);
          Q.offer(c);
        }
      }
    }

    return false;
  }
Exemplo n.º 4
0
  /** Evaluate the Insert(X, Y, T) operator (Definition 12 from Chickering, 2002). */
  private double insertEval(Node x, Node y, List<Node> t, List<Node> naYX, Graph graph) {
    Set<Node> set1 = new HashSet<Node>(naYX);
    set1.addAll(t);
    List<Node> paY = graph.getParents(y);
    set1.addAll(paY);
    Set<Node> set2 = new HashSet<Node>(set1);
    set1.add(x);

    return scoreGraphChange(y, set1, set2);
  }
Exemplo n.º 5
0
  private void addLookupArrow(Node i, Node j, Arrow arrow) {
    OrderedPair<Node> pair = new OrderedPair<Node>(i, j);
    Set<Arrow> arrows = lookupArrows.get(pair);

    if (arrows == null) {
      arrows = new HashSet<Arrow>();
      lookupArrows.put(pair, arrows);
    }

    arrows.add(arrow);
  }
Exemplo n.º 6
0
  /**
   * Forward equivalence search.
   *
   * @param graph The graph in the state prior to the forward equivalence search.
   */
  private void fes(Graph graph, List<Node> nodes) {
    TetradLogger.getInstance().log("info", "** FORWARD EQUIVALENCE SEARCH");

    lookupArrows = new HashMap<OrderedPair, Set<Arrow>>();

    initializeArrowsForward(nodes);

    while (!sortedArrows.isEmpty()) {
      Arrow arrow = sortedArrows.first();
      sortedArrows.remove(arrow);

      Node x = arrow.getX();
      Node y = arrow.getY();

      clearArrow(x, y);

      if (graph.isAdjacentTo(x, y)) {
        continue;
      }

      if (!validInsert(x, y, arrow.getHOrT(), arrow.getNaYX(), graph)) {
        continue;
      }

      List<Node> t = arrow.getHOrT();
      double bump = arrow.getBump();

      Set<Edge> edges = graph.getEdges();

      insert(x, y, t, graph, bump);
      score += bump;
      rebuildPattern(graph);

      // Try to avoid duplicating scoring calls. First clear out all of the edges that need to be
      // changed,
      // then change them, checking to see if they're already been changed. I know, roundabout, but
      // there's
      // a performance boost.
      for (Edge edge : graph.getEdges()) {
        if (!edges.contains(edge)) {
          reevaluateForward(graph, nodes, edge.getNode1(), edge.getNode2());
        }
      }

      storeGraph(graph);
    }
  }
Exemplo n.º 7
0
  // Can be done concurrently.
  private double deleteEval(Node x, Node y, List<Node> h, List<Node> naYX, Graph graph) {
    List<Node> paY = graph.getParents(y);
    Set<Node> paYMinuxX = new HashSet<Node>(paY);
    paYMinuxX.remove(x);

    Set<Node> set1 = new HashSet<Node>(naYX);
    set1.removeAll(h);
    set1.addAll(paYMinuxX);

    Set<Node> set2 = new HashSet<Node>(naYX);
    set2.removeAll(h);
    set2.addAll(paY);

    return scoreGraphChange(y, set1, set2);
  }