On Feb 6, 4:12 am, Burcin Erocal <[email protected]> wrote:
> On Sat, 5 Feb 2011 18:16:54 -0800 (PST)
>
> kcrisman <[email protected]> wrote:
>
> > > Now browse into taylor?? source, and you see that sage call the
> > > taylor function in maxima.
>
> > > The taylor function in maxima seems very long to follow in
> > > ...maxima.../src/hayat.lisp.
>
> > More to the point, Maxima doesn't know about any 'special' things you
> > define like that.  Our basic differentiation is handled by Ginac/
> > Pynac, which does not have Taylor series (does it?).  So unfortunately
> > I don't know that this is something one can (yet) do directly in
> > Sage.  It might be possible in Maxima directly, if one can define
> > custom derivatives there.
>
> The series expansion from GiNaC can be accessed with the .series()
> method. This should take into account the custom differentiation
> function.

I didn't realize this.  Is there anything (such as multivariate, order
etc.) that this is missing from Maxima series?

> Unfortunately, GiNaC has problems with series expansions around
> singularities. This was fixed recently in upstream [1], but I haven't
> checked if the fix covers all the cases reported on trac [2].
>
> [1]http://www.ginac.de/ginac.git?p=ginac.git;a=commit;h=079c558d4f9758cd...
>
> [2]http://trac.sagemath.org/sage_trac/ticket/9555
>    http://trac.sagemath.org/sage_trac/ticket/8943
>
> I really need to make a new pynac release...

In which case I really need to review it!

- kcrisman

-- 
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to 
[email protected]
For more options, visit this group at 
http://groups.google.com/group/sage-support
URL: http://www.sagemath.org

Reply via email to