Newton's Divided Difference

Using recursion, small file size

This can handle about vectors with size 20 (takes about 7 seconds for that size)
a vector of 10 only takes a fraction of a second.

Solves Newton's divided difference, which is naturally a recursive process. Seeing the recursion helps understand the process of finding divided differences.

Generally you'd only need a few coefficients, so 10 is not such a bad limit as far as speed.

Used to calculate coefficients of a interpolation polynomial

http://en.wikipedia.org/wiki/Divided_differences

Usage : divdiff(x,y), or divdiff(x,f(x)) if f is an anonymous function.

Steal my code... knowledge should be shared. Just don't try and sell it... unless you need lunch money and you've exhausted all your options, then I understand.