public static double ComputeResidual(CompressedColumnStorage <Complex> A, Complex[] x, Complex[] b, bool relativeError = true)
{
var e = Vector.Clone(b);
A.Multiply(-1.0, x, 1.0, e);
if (relativeError)
{
return(Vector.Norm(e) / (A.FrobeniusNorm() * Vector.Norm(b)));
}
return(Vector.Norm(e));
}