コード例 #1
0
  /** Calculate the shortest paths (not done per default) */
  private void lazyCalculatePaths() {
    // already we have calculated it once.
    if (paths != null) {
      return;
    }

    lazyCalculateMatrix();

    Map<VertexPair<V>, GraphPath<V, E>> sps = new HashMap<VertexPair<V>, GraphPath<V, E>>();
    int n = vertices.size();

    nShortestPaths = 0;
    for (int i = 0; i < n; i++) {
      V v_i = vertices.get(i);
      for (int j = 0; j < n; j++) {
        // don't count this.
        if (i == j) {
          continue;
        }

        V v_j = vertices.get(j);

        GraphPath<V, E> path = getShortestPathImpl(v_i, v_j);

        // we got a path
        if (path != null) {
          sps.put(new VertexPair<V>(v_i, v_j), path);
          nShortestPaths++;
        }
      }
    }

    this.paths = sps;
  }
コード例 #2
0
 private void shortestPathRecur(List<E> edges, int v_a, int v_b) {
   int k = backtrace[v_a][v_b];
   if (k == -1) {
     E edge = graph.getEdge(vertices.get(v_a), vertices.get(v_b));
     if (edge != null) {
       edges.add(edge);
     }
   } else {
     shortestPathRecur(edges, v_a, k);
     shortestPathRecur(edges, k, v_b);
   }
 }
コード例 #3
0
ファイル: CycleDetector.java プロジェクト: nicolas-f/jgrapht
    /** {@inheritDoc} */
    protected void encounterVertexAgain(V vertex, E edge) {
      super.encounterVertexAgain(vertex, edge);

      int i;

      if (root != null) {
        // For rooted detection, the path must either
        // double back to the root, or to a node of a cycle
        // which has already been detected.
        if (vertex.equals(root)) {
          i = 0;
        } else if ((cycleSet != null) && cycleSet.contains(vertex)) {
          i = 0;
        } else {
          return;
        }
      } else {
        i = path.indexOf(vertex);
      }

      if (i > -1) {
        if (cycleSet == null) {
          // we're doing yes/no cycle detection
          throw new CycleDetectedException();
        } else {
          for (; i < path.size(); ++i) {
            cycleSet.add(path.get(i));
          }
        }
      }
    }
コード例 #4
0
ファイル: GraphWalkTest.java プロジェクト: javierj/jgrapht
  public void testNonSimplePath() {
    List<Integer> vertexList = Arrays.asList(0, 1, 2, 3, 2, 3, 4);
    List<DefaultEdge> edgeList = new ArrayList<>();
    for (int i = 0; i < vertexList.size() - 1; i++)
      edgeList.add(completeGraph.getEdge(vertexList.get(i), vertexList.get(i + 1)));
    GraphPath<Integer, DefaultEdge> p1 = new GraphWalk<>(completeGraph, 0, 4, edgeList, 10);
    assertEquals(0, p1.getStartVertex().intValue());
    assertEquals(4, p1.getEndVertex().intValue());
    assertEquals(vertexList, p1.getVertexList());
    assertEquals(edgeList.size(), p1.getLength());
    assertEquals(10.0, p1.getWeight());

    GraphPath<Integer, DefaultEdge> p2 = new GraphWalk<>(completeGraph, vertexList, 10);
    assertEquals(0, p2.getStartVertex().intValue());
    assertEquals(4, p2.getEndVertex().intValue());
    assertEquals(edgeList, p2.getEdgeList());
    assertEquals(edgeList.size(), p2.getLength());
    assertEquals(10.0, p2.getWeight());
  }
コード例 #5
0
ファイル: CycleDetector.java プロジェクト: nicolas-f/jgrapht
    /** {@inheritDoc} */
    protected V provideNextVertex() {
      V v = super.provideNextVertex();

      // backtrack
      for (int i = path.size() - 1; i >= 0; --i) {
        if (graph.containsEdge(path.get(i), v)) {
          break;
        }

        path.remove(i);
      }

      path.add(v);

      return v;
    }
コード例 #6
0
ファイル: GJFfile.java プロジェクト: ekwan/utilities
  /**
   * Reads the geometry and connectivity.
   *
   * @param filename the location of the gjf file
   */
  public GJFfile(String filename) {
    super(filename);

    // read geometry
    String name = "";
    List<Atom> contents = new ArrayList<>();
    SimpleWeightedGraph<Atom, DefaultWeightedEdge> connectivity =
        new SimpleWeightedGraph<>(DefaultWeightedEdge.class);
    int blanks = 0;
    boolean lastBlank = false;
    boolean inGeometryBlock = false;
    for (List<String> line : fileContents) {
      // keep track of how many blanks we have seen
      if (line.size() == 1 && line.get(0).length() == 0) {
        if (lastBlank == false) {
          blanks++;
          lastBlank = true;
        }
        continue;
      } else lastBlank = false;

      // read the metadata
      if (blanks == 1) {
        for (String s : line) {
          String[] fields = s.split("@");
          if (fields.length != 3) continue;
          String identifier = fields[1].toLowerCase();
          String value = fields[2];
          // System.out.println(s);
          // System.out.println(identifier + " : " + value);

          if (identifier.equals("o1")) O1Number = Integer.parseInt(value);
          else if (identifier.equals("o2")) O2Number = Integer.parseInt(value);
          else if (identifier.equals("n3")) N3Number = Integer.parseInt(value);
          else if (identifier.equals("cl1")) Cl1Number = Integer.parseInt(value);
          else if (identifier.equals("su2")) Su2Number = Integer.parseInt(value);
          else if (identifier.equals("ol3")) Ol3Number = Integer.parseInt(value);
          else if (identifier.equals("mem")) mem = Integer.parseInt(value);
          else if (identifier.equals("nprocshared")) nprocshared = Integer.parseInt(value);
          else if (identifier.equals("method")) method = value;
          else if (identifier.equals("basis")) basis = value;
          else System.out.println("unrecognized entry: " + s);
        }

        continue;
      } else if (blanks != 2) continue;

      // deal with the charge and multiplicity card (by ignoring it)
      if (line.size() == 2 && inGeometryBlock == false) {
        inGeometryBlock = true;
        continue;
      }

      if (line.size() != 4 && inGeometryBlock == false)
        throw new IllegalArgumentException(
            "unexpected text in geometry block in " + filename + ":\n" + line.toString());

      // create atom
      // tinker atom types will be nonsense, of course
      Atom newAtom =
          new Atom(
              line.get(0),
              new Vector3D(
                  Double.parseDouble(line.get(1)),
                  Double.parseDouble(line.get(2)),
                  Double.parseDouble(line.get(3))),
              1);
      contents.add(newAtom);
      connectivity.addVertex(newAtom);
    }

    // read connectivity
    blanks = 0;
    lastBlank = false;
    for (List<String> line : fileContents) {
      // read the fourth block of text
      if (line.size() == 1 && line.get(0).length() == 0) {
        if (lastBlank == false) {
          blanks++;
          lastBlank = true;
        }
        continue;
      } else lastBlank = false;

      // only read connectivity lines
      if (blanks != 3) continue;

      Atom fromAtom = contents.get(Integer.parseInt(line.get(0)) - 1);
      for (int i = 1; i < line.size(); i += 2) {
        int toAtomIndex = Integer.parseInt(line.get(i)) - 1;
        Atom toAtom = contents.get(toAtomIndex);
        double bondOrder = Double.parseDouble(line.get(i + 1));
        DefaultWeightedEdge thisEdge = connectivity.addEdge(fromAtom, toAtom);
        connectivity.setEdgeWeight(thisEdge, bondOrder);
      }
    }

    // create the molecule
    molecule = new Molecule(name, contents, connectivity, 0.0);
  }