Differentiation

Hi.

I have an equation that I'd like to differentiate without using the command diff(equation). I've been told that finite-differencing should be used to get the function derivative.

http://en.wikipedia.org/wiki/Finite_difference http://en.wikipedia.org/wiki/Finite_difference_method

Can someone demonstrate how a simple example would work using matlab? That way I can try to build on it. My code currently uses the command diff but I've been told I can't use it.

[Jan]

Please explain, why you cannot use DIFF: Is it a homework and you should learn how to differentiate manually, or are there numerical reasons, e.g. the time steps are not equidistant and you need a 2nd order method?

[J]

Its to do with the newton raphson method and my teacher said that it wouldn't work unless finite differencing was used.

[Jan]

But DIFF uses a finite difference.

I assume a meaningful answer is more likely, if you post the actual problem. What kind of equation do you have and which result do you want to get?