Hi Rob! (CC to sage-combinat; this is thread [1] on sage-devel)
On Tue, Sep 04, 2012 at 07:36:51AM -0700, Rob Beezer wrote: > On Tuesday, September 4, 2012 6:21:11 AM UTC-7, John Cremona wrote: > > If pi is a permutation, e.g. defined by pi=permutations(4)[3], then > pi.signature() returns what I have always called the "sign" of pi, and > none of pi.sign(), pi.sgn(), sign(pi), sgn(pi) work. > > But: > > sage: G = SymmetricGroup(2) > sage: a = G("(1,2)") > sage: a.sign() > -1 > > So I'd say +1 to greater coordination between group element permutations > and purely combinatorial permutations overall, and in particular having > .sign() as John suggests for the "other" permutations. +1! This miscoordination has been an itch for us for quite a while. In general, Permutations need some heavy refactoring which will be best done all at once; but a simple change like this can be done right away. Cheers, Nicolas PS: https://groups.google.com/forum/?hl=fr&fromgroups=#!topic/sage-devel/DYVbTWWOMtE) -- Nicolas M. ThiƩry "Isil" <nthi...@users.sf.net> http://Nicolas.Thiery.name/ -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To post to this group, send email to sage-devel@googlegroups.com. To unsubscribe from this group, send email to sage-devel+unsubscr...@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel?hl=en.