Actually, I don't understand the merits. Why do we do it? Your case gives a clear instance where it would not be desired. Doing so manually would not be hard (just expand_log).
Aaron Meurer On Thu, May 2, 2013 at 10:04 PM, Ben Lucato <ben.luc...@gmail.com> wrote: > That's fine - I understand the merits of pulling out the powers. I'm just > looking to be able to rewrite things like 2 * log(2) as log(4) when I so > desire. Thanks for your suggestions and I will play around with them! > > On Friday, 3 May 2013 13:40:29 UTC+10, Aaron Meurer wrote: >> >> Unfortunately, log automatically pulls out powers like this. If you >> want, we could certainly discuss the merits of not having it do this. >> >> As a workaround, you can use log(4, evaluate=False). I think you could >> also subclass log and give it a custom eval that doesn't do that. >> >> Something like this seems to work >> >> class mylog(log): >> @classmethod >> def eval(self, *args): >> if args[0].is_Number: >> return None >> return super(mylog, self).eval(*args) >> >> Aaron Meurer >> >> On Thu, May 2, 2013 at 9:25 PM, Ben Lucato <ben.l...@gmail.com> wrote: >> > Not sure how to get this behavior in sympy - or even if it's possible. >> > It >> > doesn't just go for this particular example, I want to be able to do it >> > for >> > all such logs. >> > >> > >> > Many thanks!!! Sympy rocks >> > >> > -- >> > 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+un...@googlegroups.com. >> > To post to this group, send email to sy...@googlegroups.com. >> > Visit this group at http://groups.google.com/group/sympy?hl=en-US. >> > 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-US. > 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-US. For more options, visit https://groups.google.com/groups/opt_out.
