Skew-normal random variates.

def rskew_normal(mu, tau, alpha, size=()):
    """
    Skew-normal random variates.
    """
    size_ = size or (1,)
    len_ = np.prod(size_)
    return flib.rskewnorm(
        len_, mu, tau, alpha, np.random.normal(size=2 * len_)).reshape(size)