public void run() {
System.out.println("markov 0");
// Get the number of students who visit each node.
List<Trajectory> trajectories = TrajectoryLoader.load(TRAJECTORY_DIR);
System.out.println("next");
Map<String, Integer> nodeCount = new HashMap<String, Integer>();
for (Trajectory t : trajectories) {
List<String> visited = t.getProgramIds();
List<String> noCycle = new ArrayList<String>();
for (int i = 0; i < visited.size(); i++) {
String state = visited.get(i);
noCycle.add(state);
int lastIndex = visited.lastIndexOf(state);
i = lastIndex;
}
for (String v : noCycle) {
if (!nodeCount.containsKey(v)) {
nodeCount.put(v, 0);
}
int newCount = nodeCount.get(v) + t.getCount();
nodeCount.put(v, newCount);
}
}
double sumCount = 0.0;
for (String s : nodeCount.keySet()) {
sumCount += nodeCount.get(s);
}
roadMap = GraphLoader.loadRoadMap();
groundTruth = GraphLoader.loadGroundTruth();
// Make a graph where each edge has cost = coherence of the next node
System.out.println("make coherenceCost");
DirectedGraph<String> coherenceCost = new DirectedGraph<String>();
for (String node : roadMap.vertexSet()) {
double count = EPSILON;
if (nodeCount.containsKey(node)) {
count = nodeCount.get(node);
}
for (String previous : roadMap.getIncoming(node)) {
double cost = -Math.log(count / sumCount);
coherenceCost.addEdge(previous, node, cost);
}
}
// Turn it all into a prediction
System.out.println("predict");
DirectedGraph<String> bestNext = new DirectedGraph<String>();
String soln = "0";
for (String node : groundTruth.vertexSet()) {
if (node.equals(soln)) continue;
if (groundTruth.getOutgoing(node).size() == 0) continue;
List<Edge<String>> path = coherenceCost.getShortestPath(node, soln);
if (path != null) {
Edge<String> firstEdge = path.get(0);
String next = firstEdge.getTarget();
bestNext.addEdge(node, next);
}
}
System.out.println("connected: " + roadMap.getInConnected("0").size());
System.out.println("node count size: " + nodeCount.size());
System.out.println("best next size: " + bestNext.vertexSet().size());
DirectedGraph<String> toSave = new DirectedGraph<String>();
for (int i = 0; i < 1000; i++) {
String node = "" + i;
if (!bestNext.containsVertex(node)) continue;
String next = null;
for (String s : bestNext.getOutgoing(node)) {
next = s;
break;
}
if (next != null) {
toSave.addEdge(node, next);
}
}
GraphLoader.savePolicy(toSave, OUTPUT_FILE);
System.out.println("done");
}
