/*
* Should return path from initial node to terminal;
* Means getting new path-backtracker
*/
public Counter bfs(int initNode, int terminalNode) {
Counter shortestPaths = new Counter();
Counter currentNodes = new Counter();
Counter newNodes = new Counter();
shortestPaths.add(initNode, 0);
newNodes.add(initNode, 0);
while (!newNodes.isEmpty()) {
currentNodes = new Counter(newNodes);
newNodes = new Counter();
for (int r : currentNodes.keySet()) {
Counter row = this.getRow(r);
for (int c : row.keySet()) {
// Weighted case: later paths can be shorter than first path
double pathLength = currentNodes.get(r) + row.get(c);
if (pathLength < shortestPaths.getPath(c)) {
newNodes.put(c, pathLength);
shortestPaths.put(c, pathLength);
}
}
}
if (shortestPaths.getPath(terminalNode) < Double.MAX_VALUE / 2.0) {
break;
}
}
return shortestPaths;
}
public void add(int r, int c, double v) {
Counter newRow = new Counter();
newRow.add(c, v);
this.addRow(r, newRow);
rows.add(r);
cols.add(c);
}
public static Counter ConstrainedEig(SparseMatrix mat, SparseMatrix orthogMat) {
double trimEps = 0;
int iterLimit = 10000;
long start;
long end;
Counter vector = new Counter();
int vecLen = mat.colDim;
for (int i = 0; i < vecLen; i++) {
// vector.add(i, 1.0/Math.sqrt(vecLen));
vector.add(i, Math.random() - 0.5);
}
Counter oldVector = new Counter();
// vector = mat.multiply(vector);
// for(int r: orthogMat.rows){
// Counter orthogRow = orthogMat.getRow(r);
// vector.orthogonalize(orthogRow);
//// System.out.println(vector.dot(orthogRow));
// }
double norm = 0;
double sim = 0;
double diff = 1.0;
double diffNeg = 1.0;
int t = 0;
start = System.currentTimeMillis();
while (diff > Math.pow(10.0, -16.0) && diffNeg > Math.pow(10.0, -16.0) && t < iterLimit) {
t += 1;
// vector.trimKeys(trimEps);
oldVector = new Counter(vector);
vector = mat.multiply(vector);
for (int r : orthogMat.rows) {
Counter orthogRow = orthogMat.getRow(r);
// System.out.println("before: "+vector.dot(orthogRow));
vector.orthogonalize(orthogRow);
// System.out.println("after: "+vector.dot(orthogRow));
}
norm = 0;
norm = vector.norm();
vector.multiply(1.0 / norm);
diff = 0;
diffNeg = 0;
Set<Integer> vecOldUnion = vector.concreteKeySet();
vecOldUnion.addAll(oldVector.concreteKeySet());
for (int i : vecOldUnion) {
// for(int i = 0; i < mat.colDim; i++){
diff += (oldVector.get(i) - vector.get(i)) * (oldVector.get(i) - vector.get(i));
diffNeg += (oldVector.get(i) + vector.get(i)) * (oldVector.get(i) + vector.get(i));
}
sim = vector.dot(oldVector);
// System.out.println(diff+" "+diffNeg+" "+sim+" "+norm+"
// "+vector.dot(orthogMat.getRow(0)));
// System.out.println(vector.toString());
// System.out.println(oldVector.toString());
}
System.out.println(norm + " " + orthogMat.rows.size() + " " + sim);
// System.out.println(mat.toStringValues());
end = System.currentTimeMillis();
System.out.println("Time: " + (end - start) + " iterations: " + t);
return vector;
}
public static Counter TopEig(SparseMatrix mat) {
double trimEps = 0.0;
int iterLimit = 1000;
long start;
long end;
Counter vector = new Counter();
int vecLen = mat.colDim;
// for(int i = 0; i < vecLen; i++){
// vector.add(i, Math.random()-0.5);
// }
for (int i = 0; i < vecLen; i++) {
vector.add(i, 1.0 / (double) vecLen);
}
Counter oldVector = new Counter(vector);
vector = mat.multiply(vector);
double diff = 1;
int t = 0;
start = System.currentTimeMillis();
while (diff > Math.pow(10.0, -10.0) && (diff < 3.99999 || diff > 4.00001) && t < iterLimit) {
t += 1;
vector.trimKeys(trimEps);
vector = mat.multiply(vector);
double norm = 0;
for (int i : vector.keySet()) {
norm += vector.get(i) * vector.get(i);
// norm += Math.abs(vector.get(i));
}
norm = Math.sqrt(norm);
vector.multiply(1.0 / norm);
diff = 0;
Set<Integer> vecOldUnion = vector.concreteKeySet();
vecOldUnion.addAll(oldVector.concreteKeySet());
for (int i : vecOldUnion) {
diff += (oldVector.get(i) - vector.get(i)) * (oldVector.get(i) - vector.get(i));
}
System.out.println(diff + " " + norm);
// System.out.println(vector.toString());
// System.out.println(oldVector.toString());
oldVector = new Counter(vector);
}
// System.out.println(mat.toStringValues());
end = System.currentTimeMillis();
System.out.println("Time: " + (end - start) + " iterations: " + t);
return vector;
}