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import cupy as cp


def mvdr(x, sv, calc_cov=True):
    """
    Minimum variance distortionless response (MVDR) beamformer weights

    Parameters
    ----------
    x : ndarray
        Received signal or input covariance matrix, assume 2D array with
        size [num_sensors, num_samples]

    sv: ndarray
        Steering vector, assume 1D array with size [num_sensors, 1]

    calc_cov : bool
        Determine whether to calculate covariance matrix. Simply put, calc_cov
        defines whether x input is made of sensor/observation data or is
        a precalculated covariance matrix

    Note: Unlike MATLAB where input matrix x is of size MxN where N represents
    the number of array elements, we assume row-major formatted data where each
    row is assumed to be complex-valued data from a given sensor (i.e. NxM)
    """
    if x.shape[0] > x.shape[1]:
        raise ValueError(
            "Matrix has more sensors than samples. Consider \
            transposing and remember cuSignal is row-major, unlike MATLAB"
        )

    if x.shape[0] != sv.shape[0]:
        raise ValueError("Steering Vector and input data do not align")

    if calc_cov:
        x = cp.cov(x, dtype=x.dtype)

    wB = cp.linalg.inv(x).dot(sv)
    wA = sv.conj().dot(wB)  # 1x1 scalar
    return wB / wA