def METHOD_NAME(t, t_, alpha, beta, gamma=None, alpha_=0, u0=0, s0=0, sorted=False):
    """TODO."""
    with warnings.catch_warnings():
        warnings.simplefilter("ignore")
        o = np.array(t < t_, dtype=int)
    tau = t * o + (t - t_) * (1 - o)
    u0_ = unspliced(t_, u0, alpha, beta)
    s0_ = spliced(t_, s0, u0, alpha, beta, gamma if gamma is not None else beta / 2)
    # vectorize u0, s0 and alpha
    u0 = u0 * o + u0_ * (1 - o)
    s0 = s0 * o + s0_ * (1 - o)
    alpha = alpha * o + alpha_ * (1 - o)
    if sorted:
        idx = np.argsort(t)
        tau, alpha, u0, s0 = tau[idx], alpha[idx], u0[idx], s0[idx]
    return tau, alpha, u0, s0