ooops. So sorry for not reading the doc fully. The answer is to use cycle_string(singletons= True).
pierre On Jul 3, 7:38 pm, Pierre <[EMAIL PROTECTED]> wrote: > hi all, > > I'm confused with the cycle notation for permutations (bug ?) > While the following works: > > sage: Permutation( '(1,2)' ) > > the following yields an error: > > sage: Permutation( '(4,5)' ) > IndexError: list assignment index out of range > > What's confusing is that if you go: > > sage: x= Permutation( (4,5) ) > sage: s= x.cycle_string(); s > '(4,5)' > > I'm trying to build a dictionnary whose keys are permutations; since > the keys have to be hashable, i'm relying on the cycle_string() > strings. But the above issue prevents me from recovering a permutation > from its string ! > > Is there a way around this ? > > thanks > pierre --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
