Hi Maurizio, On Fri, 20 Feb 2009 16:21:36 -0800 (PST) Maurizio <maurizio.gran...@gmail.com> wrote:
> unfortunately, I don't have the code with me right now (I could give > you on monday), but I'm pretty sure it is something REALLY > straightforward and not optimized, like this: > > def coll(expr,s): > import sympy as sp > spexpr = sp.sympify(expand(expr)) > temp = sp.collect(spexpr,s) > return temp._sage_() > > var('a b c s') > prova = a*s + (b+s)*c > > coll(prova,s) > (c + a)*s + b*c Note that Pynac based symbolics already provides this functionality. sage: var('a b c s',ns=1) (a, b, c, s) sage: prova = a*s + (b+s)*c sage: prova.collect(s) (a + c)*s + b*c I hope to start the switch to use pynac as the default backend for symbolics soon, but I'm still reluctant to give a time frame. As to your original remark: > I am wondering what do you think about simplifying the access and use > of the external packages to accomplish some very simple operations. I > first say that I do intensive use of plot and symbolic analysis > (calculus) routines. Please point out other functionality that you think should be exposed through a better interface. I agree that we should do a better job in this area. Cheers, Burcin --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---