dpnp.linalg.matrix_rank

dpnp.linalg.matrix_rank(A, tol=None, hermitian=False)[source]

Return matrix rank of array using SVD method.

Rank of the array is the number of singular values of the array that are greater than tol.

Parameters:

  • A ({(M,), (..., M, N)} {dpnp.ndarray, usm_ndarray}) – Input vector or stack of matrices.

  • tol ((...) {float, dpnp.ndarray, usm_ndarray}, optional) – Threshold below which SVD values are considered zero. If tol is None, and S is an array with singular values for M, and eps is the epsilon value for datatype of S, then tol is set to S.max() * max(M.shape) * eps.

  • hermitian (bool, optional) – If True, A is assumed to be Hermitian (symmetric if real-valued), enabling a more efficient method for finding singular values. Defaults to False.

Returns:

rank – Rank of A.

Return type:

(…) dpnp.ndarray

See also

dpnp.linalg.svd

Singular Value Decomposition.

Examples

>>> import dpnp as np
>>> from dpnp.linalg import matrix_rank
>>> matrix_rank(np.eye(4)) # Full rank matrix
array(4)
>>> I=np.eye(4); I[-1,-1] = 0. # rank deficient matrix
>>> matrix_rank(I)
array(3)
>>> matrix_rank(np.ones((4,))) # 1 dimension - rank 1 unless all 0
array(1)
>>> matrix_rank(np.zeros((4,)))
array(0)