low_rank_toolbox.cssp.utils.sRRQR

low_rank_toolbox.cssp.utils.sRRQR(A, eta, mode, param)[source]

Dispatcher for Strong Rank-Revealing QR factorization.

This function automatically detects if the input matrix A is real or complex and calls the appropriate implementation.

Parameters:

  • (np.ndarray) (A)

  • (float) (eta)

  • (str) (mode)

  • float) (param (int or) –

    • If mode is ‘rank’, param is the desired rank k.

    • If mode is ‘tol’, param is the error tolerance.

  • A (ndarray)

  • eta (float)

  • mode (str)

  • param (float)

Return type:

tuple[ndarray, ndarray, ndarray]

Returns:

tuple[np.ndarray, np.ndarray, np.ndarray]:

  • Q (np.ndarray): Truncated unitary/orthogonal matrix $Q_1$.

  • R (np.ndarray): Truncated upper triangular matrix $[R_{11}, R_{12}]$.

  • p (np.ndarray): The column permutation vector.