def singular_values(self):
        mat = self.as_mutable()
        # Compute eigenvalues of A.H A
        valmultpairs = (mat.H*mat).eigenvals()

        # Expands result from eigenvals into a simple list
        vals = []
        for k, v in valmultpairs.items():
            vals += [sqrt(k)]*v  # dangerous! same k in several spots!
        # sort them in descending order
        vals.sort(reverse=True, key=default_sort_key)

        return vals
Compute the singular values of a Matrix
dataset/ETHPy150Open sympy/sympy/sympy/matrices/matrices.py/MatrixBase.singular_values