def zerocross(eigenvec):
    """
    Compute the amount of zero-crossing of an eigenvector matrix (for each eigenvector).

    Parameters
    ----------
    eigenvec : numpy.ndarray
        The eigenvectors from a decomposition.

    Returns
    -------
    numpy.ndarray
        A 1D array with the amount of zero-crossing for each eigenvector.
    """
    return (eigenvec[:-1, ...] * eigenvec[1:, ...] < 0).sum(axis=0)