1.7.0

    The results have only been tested up to degree 100, higher degrees may
    be problematic. The weights are determined by using the fact that

    .. math:: w_k = c / (H'_n(x_k) * H_{n-1}(x_k))

    where :math:`c` is a constant independent of :math:`k` and :math:`x_k`
    is the k'th root of :math:`H_n`, and then scaling the results to get
    the right value when integrating 1.

    r-