/**
* Computes the "cost" for the parameters given.
*
* cost = (1/N) Sum (f(x;p) - y)^2
*/
private double cost(DMatrixRMaj param, DMatrixRMaj X, DMatrixRMaj Y)
{
func.compute(param, X, temp0);
double error = SpecializedOps_DDRM.diffNormF(temp0, Y);
return(error * error / (double)X.numRows);
}
public static double quality(DMatrixRMaj orig, DMatrixRMaj U, DMatrixRMaj W, DMatrixRMaj Vt)
{
// foundA = U*W*Vt
DMatrixRMaj UW = new DMatrixRMaj(U.numRows, W.numCols);
CommonOps_DDRM.mult(U, W, UW);
DMatrixRMaj foundA = new DMatrixRMaj(UW.numRows, Vt.numCols);
CommonOps_DDRM.mult(UW, Vt, foundA);
double normA = NormOps_DDRM.normF(foundA);
return(SpecializedOps_DDRM.diffNormF(orig, foundA) / normA);
}
