On Fri, Feb 22, 2013 at 12:24 AM, Matthew Rocklin <[email protected]> wrote: > Ah, yes, that is helpful. > > In general I'm looking for an automated solution for problems like this. > I'd like to solve this problem without being smart :) >
maybe as ``` >>> e = (-L**2+6*L+4*f(i))/4/L >>> co, t = e.expand().as_independent(i, as_Add=True) >>> p, ei = factor_terms(t).as_independent(i, as_Add=False) >>> n*co+p*Sum(ei,(i,1,n)) n*(-L/4 + 3/2) + Sum(f(i), (i, 1, n))/L ``` If the expression is a Mul then we have separatevars that will try separate out the i-term(s); we don't have a general method for trying hard to make something an Add with terms separated out. Aaron and I discussed this a bit and I proposed a routine for doing mv separation at http://code.google.com/p/sympy/issues/detail?id=2032#c11. So perhaps you could use the apart part first, followed by a separatevars on the t-term if it was a Mul. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
