コード例 #1
0
 /**
  * The basic method for splitting off a clause of a tree. This modifies the tree in place.
  *
  * @param tree The tree to split a clause from.
  * @param toKeep The edge representing the clause to keep.
  */
 static void splitToChildOfEdge(SemanticGraph tree, SemanticGraphEdge toKeep) {
   Queue<IndexedWord> fringe = new LinkedList<>();
   List<IndexedWord> nodesToRemove = new ArrayList<>();
   // Find nodes to remove
   // (from the root)
   for (IndexedWord root : tree.getRoots()) {
     nodesToRemove.add(root);
     for (SemanticGraphEdge out : tree.outgoingEdgeIterable(root)) {
       if (!out.equals(toKeep)) {
         fringe.add(out.getDependent());
       }
     }
   }
   // (recursively)
   while (!fringe.isEmpty()) {
     IndexedWord node = fringe.poll();
     nodesToRemove.add(node);
     for (SemanticGraphEdge out : tree.outgoingEdgeIterable(node)) {
       if (!out.equals(toKeep)) {
         fringe.add(out.getDependent());
       }
     }
   }
   // Remove nodes
   nodesToRemove.forEach(tree::removeVertex);
   // Set new root
   tree.setRoot(toKeep.getDependent());
 }
コード例 #2
0
  /**
   * A helper to add an entire subtree to a given dependency tree.
   *
   * @param toModify The tree to add the subtree to.
   * @param root The root of the tree where we should be adding the subtree.
   * @param rel The relation to add the subtree with.
   * @param originalTree The orignal tree (i.e., {@link ClauseSplitterSearchProblem#tree}).
   * @param subject The root of the clause to add.
   * @param ignoredEdges The edges to ignore adding when adding this subtree.
   */
  private static void addSubtree(
      SemanticGraph toModify,
      IndexedWord root,
      String rel,
      SemanticGraph originalTree,
      IndexedWord subject,
      Collection<SemanticGraphEdge> ignoredEdges) {
    if (toModify.containsVertex(subject)) {
      return; // This subtree already exists.
    }
    Queue<IndexedWord> fringe = new LinkedList<>();
    Collection<IndexedWord> wordsToAdd = new ArrayList<>();
    Collection<SemanticGraphEdge> edgesToAdd = new ArrayList<>();
    // Search for subtree to add
    for (SemanticGraphEdge edge : originalTree.outgoingEdgeIterable(subject)) {
      if (!ignoredEdges.contains(edge)) {
        if (toModify.containsVertex(edge.getDependent())) {
          // Case: we're adding a subtree that's not disjoint from toModify. This is bad news.
          return;
        }
        edgesToAdd.add(edge);
        fringe.add(edge.getDependent());
      }
    }
    while (!fringe.isEmpty()) {
      IndexedWord node = fringe.poll();
      wordsToAdd.add(node);
      for (SemanticGraphEdge edge : originalTree.outgoingEdgeIterable(node)) {
        if (!ignoredEdges.contains(edge)) {
          if (toModify.containsVertex(edge.getDependent())) {
            // Case: we're adding a subtree that's not disjoint from toModify. This is bad news.
            return;
          }
          edgesToAdd.add(edge);
          fringe.add(edge.getDependent());
        }
      }
    }
    // Add subtree
    // (add subject)
    toModify.addVertex(subject);
    toModify.addEdge(
        root,
        subject,
        GrammaticalRelation.valueOf(Language.English, rel),
        Double.NEGATIVE_INFINITY,
        false);

    // (add nodes)
    wordsToAdd.forEach(toModify::addVertex);
    // (add edges)
    for (SemanticGraphEdge edge : edgesToAdd) {
      assert !toModify.incomingEdgeIterator(edge.getDependent()).hasNext();
      toModify.addEdge(
          edge.getGovernor(),
          edge.getDependent(),
          edge.getRelation(),
          edge.getWeight(),
          edge.isExtra());
    }
  }