import numpy as np
from typing import cast, List
from numpy.typing import NDArray

def null( A: NDArray[ np.float64 ] ) -> NDArray[ np.float64 ]:
    A = np.atleast_2d(A)
    u, s, vh = np.linalg.svd(A)
    tol = max(1e-13, 0)
    nnz = (s >= tol).sum()
    return vh[nnz:].conj()

import run_tests