Hi David, On Mon, 12 Jul 2010 02:24:41 -0700 (PDT) David Sanders <dpsand...@gmail.com> wrote:
> On Jul 11, 8:13 pm, "ma...@mendelu.cz" <ma...@mendelu.cz> wrote: > > On 11 čnc, 12:22, William Stein <wst...@gmail.com> wrote: > > > > > On Sat, Jul 10, 2010 at 10:04 PM, David Sanders > > > <dpsand...@gmail.com> wrote: > > > > > Maybe > > > > > http://sagemath.org/doc/reference/calculus.html > > > > Perhaps > > alsohttp://www.ginac.de/tutorial/Pattern-matching-and-advanced-substituti... > > > > OK, that is also useful, thanks. > In particular, I notice that there is the concept of indexed objects > in GiNaC. > Is this accessible from Sage? There is an experimental patch. I'm really busy these days, but this is close to the top of my list. :) http://groups.google.com/group/sage-devel/t/69ab50fe11672111 > > Or pass to Maxima and use pattern matching from Maxima, which is > > well documented in documantation to Maxima. > > I am now confused about which system is used for the symbolics in > Sage? Is it GiNaC, or Maxima, or a mixture? How can I find out which > system is being used for which operation? It's a mixture, though we are trying to move as much as possible to GiNaC and native Sage. AFAIK, the only way to tell what is being used is to read the code. As a general rule, basic arithmetic and pattern matching is done with GiNaC, more advanced functionality, limits, simplification, factorization, etc. calls maxima. > I would very much prefer not to have to learn Maxima if I can help it, > since the whole point is that Sage is supposed to provide the nice, > coherent interface which makes this unnecessary! I can totally understand that. We definitely need to improve the interface to cover this functionality. Thanks for pointing it out. > I also note that after reading the documentation, I am still left > without an answer to my original question, which is how to do pattern > matching in Sage (or if it's even possible) for something of the > form > f(i) ! I don't think this is supported by GiNaC expressions at the moment. If using wildcards for functions is available in GiNaC, we can wrap it easily. Implementing it would take more time though. Can you ask the GiNaC list if this is possible purely using GiNaC (from C++)? Cheers, Burcin -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
