To pull apart expressions in general in SymPy, use .args, like >>> Sum(f(x), (x, 0, oo)).args (f(x), (x, 0, ∞)) >>> Sum(f(x), (x, 0, oo)).args[0] f(x)
See http://docs.sympy.org/0.7.3/tutorial/manipulation.html. Aaron Meurer On Sat, Aug 17, 2013 at 5:04 PM, <echelon3.ns...@wanadoo.fr> wrote: > Hi everyone, > > I'm trying to solve linear ODEs, using the Frobenius method (ie. with power > series). The idea is to obtain a_n in a summation with the following form : > > y_n(x) = Sum(a_n, (n, 0, oo)) > > > I guess such a mehod already exist but I didn't manage to find it. > > Thanks in advance > > -- > 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 sympy+unsubscr...@googlegroups.com. > To post to this group, send email to sympy@googlegroups.com. > Visit this group at http://groups.google.com/group/sympy. > For more options, visit https://groups.google.com/groups/opt_out. -- 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 sympy+unsubscr...@googlegroups.com. To post to this group, send email to sympy@googlegroups.com. Visit this group at http://groups.google.com/group/sympy. For more options, visit https://groups.google.com/groups/opt_out.
