info prev up next book cdrom email home

Newton's Divided Difference Interpolation Formula

Let

\begin{displaymath}
\pi_n(x)\equiv \prod_{i=1}^n (x-x_n),
\end{displaymath} (1)

then
\begin{displaymath}
f(x)=f_0+\sum_{k=1}^n x_{k-1}(x)[x_0, x_1, \ldots, x_k]+R_n,
\end{displaymath} (2)

where $[x_1, \dots]$ is a Divided Difference, and the remainder is
\begin{displaymath}
R_n(x)=\pi_n(x)[x_0, \ldots, x_n, x]=\pi_n(x){f^{(n+1)}(\xi)\over (n+1)}
\end{displaymath} (3)

for $x_0<\xi<x_n$.

See also Divided Difference, Finite Difference


References

Abramowitz, M. and Stegun, C. A. (Eds.). Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 9th printing. New York: Dover, p. 880, 1972.

Hildebrand, F. B. Introduction to Numerical Analysis. New York: McGraw-Hill, pp.43-44 and 62-63, 1956.




© 1996-9 Eric W. Weisstein
1999-05-25