def METHOD_NAME(self, x, x0):
    """
    @brief 虚单元基函数在边上lagrange插值
    @param x0 是插值点
    @param x 是已知点,此处值为1 其余为0
    @example qf = GaussLobattoQuadrature(p + 2) # NQ
        qf0 = GaussLobattoQuadrature(p+1)
        phi = space.edge_basis(qf0.quadpts[:, 0], qf.quadpts[:, 0])
    """
    A = x[:, None] - x[None, :]
    A[np.arange(len(A)), np.arange(len(A))] = 1.0
    A = np.prod(A, axis=1)
    val = np.zeros((len(x0), len(x)), dtype=np.float_)
    for i in range(len(x)):
        flag = np.ones(len(x), dtype=np.bool_)
        flag[i] = False
        val[:, i] = np.prod(x0[:, None] - x[flag][None, :], axis=1)/A[i]
    return val