Re: Finding Taylor Coefficients Using Octave

[Carlo de Falco]

On 24/mar/08, at 03:33, Gregg Anderson wrote:
> Sirs,
> In MATLAB one can find the 15th-order Taylor polynomial of f(x) =  
> x^3*tan(x^2) (assuming you have the symbolic module installed) by  
> typing at the command line the following:
>
>        >> taylor(x^3*tan(x^2),16)       ->ans = x^5+1/3*x^9+2/15*x^13
>
> MATLAB is using n! = gamma(n+1).
>
> How can I do this using Octave?

Octave is intended to perform numerical computions,
things like the one you want to do are done better with a symbolic  
manipulation tool
like for example Maxima.
Nevertheless I suspect that something similar can be done within  
Octave using the "symbolic"
package which links to GiNaC.
I am not familiar with that package but at least it does contain a  
function called "differentiate" which looks promising.

<snip>
> Also, any documentation on how to actually use these packages?

pkg describe -verbose symbolic

will give you a list of functions in the package
then, for example,

help differentiate

tells you how to use the function, for more help on managing packages  
try

doc pkg

> Thanks.
> Gregg  Anderson

c.