Hi Florent, On Thu, 17 Nov 2011 14:44:35 +0100 Florent Hivert <florent.hiv...@lri.fr> wrote:
> On Wed, Nov 16, 2011 at 03:48:10PM +0100, Burcin Erocal wrote: > > On Wed, 16 Nov 2011 15:10:54 +0100 > > Florent Hivert <florent.hiv...@lri.fr> wrote: > > > > > > Pynac supports indexed expressions already. It just isn't > > > > wrapped in Sage yet. Again, there is an experimental patch > > > > available: > > > > > > > > http://sage.math.washington.edu/home/burcin/indexed_expression-20110727.patch > > > > > > > > Since you can wrap any hashable Python object in a symbolic > > > > expression with SR._force_pyobject(), this could replace your > > > > IndexedVarExpr class. > > > > > > > > I would appreciate any help with cleaning up these patches, > > > > adding doctests etc. so they can be merged. :) > > > > > > I'll try to cleanup this one, though I don't know anything about > > > Pynac's internal... Is there a lot more work to do than adding > > > doctests ? > > > > It should be only doctests, but you never know what comes up. :) > > > > I haven't looked at the patch in detail. I don't recall if any low > > level modification is needed. I'll be on IRC if you run into > > anything. > > I'm at a conference so I don't have that much time working on it right > now. I'll probably have more time next week. > > My two first attempts weren't successful: first of all, it seems that > you cannot index variables by any Python objects, only integers or > sequences of thereof. I typically want to put permutations, trees or > group elements in the index. Is that a limitation of Pynac or of your > wrapper ? This was a limitation of the wrapper. It tries to coerce the argument to SR. If Pynac doesn't need to do any arithmetic with these objects, one can skip the coercion rules with the SR._force_pyobject() function. I updated the patch to allow arbitrary (hashable) Python objects and omit the dimension argument. > Second, I got some Segfault so there is probably more work that only > doctest. I have to investigate more to get a simple reproducible > behavior. Can you check that I have the latest version of your patch: > it is called: indexed_expression-20110727.patch That was the latest version. :) Here is a new one: http://sage.math.washington.edu/home/burcin/indexed_expression_20111118.patch Note that I never actually used this. It is possible that there are problems. I can try to fix these when you have a simple example. It's possible that your segfault is caused by #9880. We are trying to finish that ticket off for the next release. Unfortunately, I am really short on time these days. Cheers, Burcin -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
