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; }
public static Graph erdosRenyiGraph(int n, int e) { List<Node> nodes = new ArrayList<Node>(); for (int i = 0; i < n; i++) nodes.add(new GraphNode("X" + i)); Graph graph = new EdgeListGraph(nodes); for (int e0 = 0; e0 < e; e0++) { int i1 = RandomUtil.getInstance().nextInt(n); int i2 = RandomUtil.getInstance().nextInt(n); if (i1 == i2) { e0--; continue; } Edge edge = Edges.undirectedEdge(nodes.get(i1), nodes.get(i2)); if (graph.containsEdge(edge)) { e0--; continue; } graph.addEdge(edge); } return graph; }
private Graph pickDag(Graph graph) { SearchGraphUtils.basicPattern(graph, false); addRequiredEdges(graph); boolean containsUndirected; do { containsUndirected = false; for (Edge edge : graph.getEdges()) { if (Edges.isUndirectedEdge(edge)) { containsUndirected = true; graph.removeEdge(edge); Edge _edge = Edges.directedEdge(edge.getNode1(), edge.getNode2()); graph.addEdge(_edge); } } meekOrient(graph, getKnowledge()); } while (containsUndirected); return graph; }
public static Graph weightedRandomGraph(int n, int e) { List<Node> nodes = new ArrayList<Node>(); for (int i = 0; i < n; i++) nodes.add(new GraphNode("X" + i)); Graph graph = new EdgeListGraph(nodes); for (int e0 = 0; e0 < e; e0++) { int i1 = weightedRandom(nodes, graph); // int i2 = RandomUtil.getInstance().nextInt(n); int i2 = weightedRandom(nodes, graph); if (!(shortestPath(nodes.get(i1), nodes.get(i2), graph) < 9)) { e0--; continue; } if (i1 == i2) { e0--; continue; } Edge edge = Edges.undirectedEdge(nodes.get(i1), nodes.get(i2)); if (graph.containsEdge(edge)) { e0--; continue; } graph.addEdge(edge); } for (Edge edge : graph.getEdges()) { Node n1 = edge.getNode1(); Node n2 = edge.getNode2(); if (!graph.isAncestorOf(n2, n1)) { graph.removeEdge(edge); graph.addDirectedEdge(n1, n2); } else { graph.removeEdge(edge); graph.addDirectedEdge(n2, n1); } } return graph; }
/** Get all nodes that are connected to Y by an undirected edge and not adjacent to X. */ private static List<Node> getTNeighbors(Node x, Node y, Graph graph) { List<Edge> yEdges = graph.getEdges(y); List<Node> tNeighbors = new ArrayList<Node>(); for (Edge edge : yEdges) { if (!Edges.isUndirectedEdge(edge)) { continue; } Node z = edge.getDistalNode(y); if (graph.isAdjacentTo(z, x)) { continue; } tNeighbors.add(z); } return tNeighbors; }
/** * Find all nodes that are connected to Y by an undirected edge that are adjacent to X (that is, * by undirected or directed edge). */ private static List<Node> getNaYX(Node x, Node y, Graph graph) { List<Edge> yEdges = graph.getEdges(y); List<Node> nayx = new ArrayList<Node>(); for (Edge edge : yEdges) { if (!Edges.isUndirectedEdge(edge)) { continue; } Node z = edge.getDistalNode(y); if (!graph.isAdjacentTo(z, x)) { continue; } nayx.add(z); } return nayx; }
private void initializeArrowsBackward(Graph graph) { sortedArrows.clear(); lookupArrows.clear(); for (Edge edge : graph.getEdges()) { Node x = edge.getNode1(); Node y = edge.getNode2(); if (!knowledgeEmpty()) { if (!getKnowledge().noEdgeRequired(x.getName(), y.getName())) { continue; } } if (Edges.isDirectedEdge(edge)) { calculateArrowsBackward(x, y, graph); } else { calculateArrowsBackward(x, y, graph); calculateArrowsBackward(y, x, graph); } } }
/** Do an actual deletion (Definition 13 from Chickering, 2002). */ private void delete(Node x, Node y, List<Node> subset, Graph graph, double bump) { Edge trueEdge = null; if (trueGraph != null) { Node _x = trueGraph.getNode(x.getName()); Node _y = trueGraph.getNode(y.getName()); trueEdge = trueGraph.getEdge(_x, _y); } if (log && verbose) { Edge oldEdge = graph.getEdge(x, y); String label = trueGraph != null && trueEdge != null ? "*" : ""; TetradLogger.getInstance() .log( "deletedEdges", (graph.getNumEdges() - 1) + ". DELETE " + oldEdge + " " + subset + " (" + bump + ") " + label); out.println( (graph.getNumEdges() - 1) + ". DELETE " + oldEdge + " " + subset + " (" + bump + ") " + label); } else { int numEdges = graph.getNumEdges() - 1; if (numEdges % 50 == 0) out.println(numEdges); } graph.removeEdge(x, y); for (Node h : subset) { Edge oldEdge = graph.getEdge(y, h); graph.removeEdge(y, h); graph.addDirectedEdge(y, h); if (log) { TetradLogger.getInstance() .log("directedEdges", "--- Directing " + oldEdge + " to " + graph.getEdge(y, h)); } if (verbose) { out.println("--- Directing " + oldEdge + " to " + graph.getEdge(y, h)); } if (Edges.isUndirectedEdge(graph.getEdge(x, h))) { if (!graph.isAdjacentTo(x, h)) throw new IllegalArgumentException("Not adjacent: " + x + ", " + h); oldEdge = graph.getEdge(x, h); graph.removeEdge(x, h); graph.addDirectedEdge(x, h); if (log) { TetradLogger.getInstance() .log("directedEdges", "--- Directing " + oldEdge + " to " + graph.getEdge(x, h)); } if (verbose) { out.println("--- Directing " + oldEdge + " to " + graph.getEdge(x, h)); } } } }