航空学报 > 1989, Vol. 10 Issue (10): 540-544

由等距基点直接构造插值多项式的一种新算法

孙德辉   

  1. 北京航空航天大学
  • 收稿日期:1988-04-25 修回日期:1900-01-01 出版日期:1989-10-25 发布日期:1989-10-25

A NEW ALGORITHM ALLOWING DIRECT CONSTRUCTION OF POLYNOMIAL INTERPOLATING FUNCTIONS WITH EQUALLY-SPACED DATA POINTS

Sun Dehui   

  1. Beijing University of Aeronautics and Astronautics
  • Received:1988-04-25 Revised:1900-01-01 Online:1989-10-25 Published:1989-10-25

摘要:

现有插值方法,一般都不把插值函数直接表示为代数多项式。本文将提出一种求取插值多项式的分次算法(split-degree argorithm),可由插值多项式的高次项到其相邻的低次项,通过十分简单的运算,每次算出两个项的系数。本算法的使用限制是插值基点必须等间距。由于本法使用的是相邻差商或差分,故计算工作量小,计算速度快,且可手算。本文算法非常独特,它既不是拉格朗日法,也不是牛顿法。

关键词: 数值逼近, 代数插值, 曲线拟合

Abstract:

Interpolation methods so far available do not give the interpolating functions directly in the form of algebraic polynomials. The split-degree method of interpolation which the present paper has put forward gives a unique algorithm. With this method the construction of interpolating algebraic polynomials can be carried out by obtaining simultaneously two coefficients of a higher-degree term and its adjacent lower-degree term at a time and in a very simple way. The new algorithm involves only the calculation of adjacent quotient-differences or simply, adjacent differences, thus minimizing the calculation and allowing a fast computing speed. The method is neither Lagrange nor Newton method. A limitation of its application is the requirement of equally-spaced data points.

Key words: numerical approximation, algebraic interpolation, curve fitting