@Override
public double[][] getKernelMatrix(List<TrainingSample<T>> list) {
final List<TrainingSample<T>> l = list;
// init matrix with ones
double matrix[][] = new double[l.size()][l.size()];
for (double[] lines : matrix) Arrays.fill(lines, 1.);
for (final Kernel<T> k : kernels.keySet()) {
final double w = kernels.get(k);
// check w
if (w == 0) continue;
final double[][] m = k.getKernelMatrix(l);
// specific factory
ThreadedMatrixOperator tmo =
new ThreadedMatrixOperator() {
@Override
public void doLine(int index, double[] line) {
for (int i = line.length - 1; i >= 0; i--) {
line[i] *= Math.pow(m[index][i], w);
}
};
};
tmo.getMatrix(matrix);
}
return matrix;
}
@Override
public double valueOf(T t1, T t2) {
double sum = 1.;
for (Kernel<T> k : kernels.keySet()) {
double w = kernels.get(k);
if (w != 0) sum *= Math.pow(k.valueOf(t1, t2), kernels.get(k));
}
return sum;
}