There's no consistency here. Aside from the two issues you mentioned, there's also https://code.google.com/p/sympy/issues/detail?id=2571. So Lambda, Subs, and Integral are three classes that use bound variables, and each treats them slightly differently. We need to figure out which treatment makes the most sense and use it everywhere.
Sum and Product are two others. I assume they work the same as Integral, though without https://code.google.com/p/sympy/issues/detail?id=3662 it's hard to be sure. Aaron Meurer On Tue, Mar 12, 2013 at 6:34 PM, Renato Coutinho <renato.couti...@gmail.com> wrote: > Hi Chris, > > I rebased my two-years-old branch and noticed that things changed > quite a bit, so I tried again and I think I managed to do it. Please > take a look at PR 1888 (https://github.com/sympy/sympy/pull/1888). > > I was caught by surprise by the changes in Subs, now it doesn't use > dummies internally anymore. In the end, issues 2440 and 2442 were > settled in favor of always keeping the original variables and > comparing complex objects different if internal variables are > different? Also, looking at commit aac30a2ba7, I see that > > Subs(f(x), x, 0).subs(x, 1).doit() == f(1) > > so subs() should be interpreted as structural substitution, being able > to break mathematical consistency. Are there other ways to substitute > variables ignoring bound variables? This behavior is producing some > bugs in the code I just submitted, but they are a bit hard to detect > because they are triggered by cache (that is, they don't appear with > cache turned off). > > Cheers, > Renato > > On Sun, Mar 10, 2013 at 3:16 AM, Chris Smith <smi...@gmail.com> wrote: >> Thanks for the heads up! >> >> -- >> 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?hl=en. >> 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?hl=en. > 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?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
