public static double Determinant_NonRecursive(MMatrix A)
{
double det = 1;
if (!A.IsSquared())
throw new MMatrixException("Determinant of a non-square matrix doesn't exist");
A.FactorLU_withP();
for (int i = 0; i < A.row; ++i)
det *= A.LU_L[i, i] * A.LU_U[i, i];
det *= Determinant(new MMatrix(A.LU_P));
return det;
}
public static void FactorLU(MMatrix squaredMatrix)
{
if (!squaredMatrix.IsSquared())
throw new MMatrixException("Matrix is non-square. LU factorization impossible.");
FactorLU(squaredMatrix, squaredMatrix.row);
}
public static double SpectralRadius(MMatrix A)
{
Vector Eigenvalues = new Vector();
if (!A.IsSquared())
throw new MMatrixException("Matrix must be squared.");
Eigenvalues = A.QRIterationBasic(GlobalMath.MAXITER).DiagVector();
Eigenvalues.Sort(true);
return Math.Abs(Eigenvalues[0]);
}
