The Permutation0 might be a good idea, I don't know... It wouldn't change the tuple vs. list thing which is used to distinguish between the cycle notation and the word notation.
I agree some of the syntax could be improved. But I do think backward compatibility is important. It's really annoying when you have to rewrite ALL your old personal code when you update your sage version (which happens all the time), and I know it's a put-off for many people (and Sage has quite a bad reputation for it). Also, Nathann, please do not assume that you represent all the Sage coders. I'm a Sage coder and user, and I use 1-Permutation. I use them ALL THE TIME and I need them. In every single of my programs, because permutation is my main object of study! And the users you seem to so easily ignore are contributors too. They contribute to algorithms and maps on permutations that are useful to everyone. The fact is that in the math world, in every single paper about the symmetric group, the permutations are 1-Permutations and it makes sense to have them. As Volker says, it's an old debate and you can't just erase everyone else's work and point of views because it suits you. The fact that it makes you lose time is bad and yes, we have to do something about it. But there is no simple answer and people are making efforts to handle all these different situations as best as they could. Cheers Viviane 2014-09-05 22:16 GMT+02:00 Volker Braun <vbraun.n...@gmail.com>: > The whole 0 vs. 1 based permutations (Python vs. Matlab :-) is always > confusing. And there is good reason and history in both conventions, so we > should IMHO accept that we'll have to live with it. Its not something that > can be solved satisfactorily by trying to guess the user's intentions, you > can never say for sure if thats a 0-based permutation that just doesn't act > on 0. > > So how about making it explicit, have separate Permutation and > Permutation0 (instead of tuple vs list). They can share most of the > backend, its just a slightly different set that they operate on. In Code, > you just call sigma = Permutation0(sigma) on user input in the beginning to > convert it to your desired presentation if you depend on the actual > integers. > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
