三階拉格朗日內差法。使用了Farrow結構，簡化三階多項式係數之運算。-third-order Lagrange interpolation algorithm. use Farrow structure to simplify the coefficients of the polynomial of Lagrange method.

lagrange插值,用于分数时延滤波器farrow结构系数求解(Lagrange interpolation for fractional delay filter Farrow structure coefficient solution)