拉格朗日插值法只能算是数学意义上的插值，从插值基函数的巧妙选取，已经构造性的证明了插值法的存在性和惟一性-Lagrange interpolation can only be regarded as the mathematical sense of the interpolation, from the clever interpolation basis function selection, has been constructive proof of the existence of the interpolation method and uniqueness of