Exemplo n.º 1
0
def iddr_rsvd(m, n, matvect, matvec, k):
    """
    Compute SVD of a real matrix to a specified rank using random matrix-vector
    multiplication.

    :param m:
        Matrix row dimension.
    :type m: int
    :param n:
        Matrix column dimension.
    :type n: int
    :param matvect:
        Function to apply the matrix transpose to a vector, with call signature
        `y = matvect(x)`, where `x` and `y` are the input and output vectors,
        respectively.
    :type matvect: function
    :param matvec:
        Function to apply the matrix to a vector, with call signature
        `y = matvec(x)`, where `x` and `y` are the input and output vectors,
        respectively.
    :type matvec: function
    :param k:
        Rank of SVD.
    :type k: int

    :return:
        Left singular vectors.
    :rtype: :class:`numpy.ndarray`
    :return:
        Right singular vectors.
    :rtype: :class:`numpy.ndarray`
    :return:
        Singular values.
    :rtype: :class:`numpy.ndarray`
    """
    U, V, S, ier = _id.iddr_rsvd(m, n, matvect, matvec, k)
    if ier != 0:
        raise _RETCODE_ERROR
    return U, V, S
Exemplo n.º 2
0
def iddr_rsvd(m, n, matvect, matvec, k):
    """
    Compute SVD of a real matrix to a specified rank using random matrix-vector
    multiplication.

    :param m:
        Matrix row dimension.
    :type m: int
    :param n:
        Matrix column dimension.
    :type n: int
    :param matvect:
        Function to apply the matrix transpose to a vector, with call signature
        `y = matvect(x)`, where `x` and `y` are the input and output vectors,
        respectively.
    :type matvect: function
    :param matvec:
        Function to apply the matrix to a vector, with call signature
        `y = matvec(x)`, where `x` and `y` are the input and output vectors,
        respectively.
    :type matvec: function
    :param k:
        Rank of SVD.
    :type k: int

    :return:
        Left singular vectors.
    :rtype: :class:`numpy.ndarray`
    :return:
        Right singular vectors.
    :rtype: :class:`numpy.ndarray`
    :return:
        Singular values.
    :rtype: :class:`numpy.ndarray`
    """
    U, V, S, ier = _id.iddr_rsvd(m, n, matvect, matvec, k)
    if ier != 0:
        raise _RETCODE_ERROR
    return U, V, S