Jerome Lefebvre wrote: > > Bizarre error reporting with symmetric functions; > > ---------------------------------------------------------------------- > | Sage Version 4.1, Release Date: 2009-07-09 | > | Type notebook() for the GUI, and license() for information. | > ---------------------------------------------------------------------- > sage: H = SymmetricFunctionAlgebra(QQ, basis='homogeneous') > sage: f = H(0) > sage: print f > 0 > sage: g = f.expand(3, alphabet=['x_1','x_2','x_3']) > > This then gives me;
<Boom> > > If it's not implemented, why such a round about error message? > > Also, shouldn't H([0]) work to give 1? and H([-1]) work to give me > zero? I.e. H([0]) is the sum of all the monomials of degree 0, i.e. 1. > I'm using Harris and Fulton's Representation theory a first course as > a guide for theses things. Dear Jerome, You are completely correct that this should work. Thank you for reporting it. Sage currently uses the 'Symmetrica' library for these sorts of calculations, and we've discovered that it often has problems with 'zero' functions. We've fixed some of these bugs, but clearly not all of them. I've created a ticket for what you reported at http://sagetrac.org/sage_trac/ticket/6665 A closely related ticket is at http://sagetrac.org/sage_trac/ticket/6487 Cheers, Jason --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sage-combinat-devel" group. To post to this group, send email to sage-combinat-devel@googlegroups.com To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en -~----------~----~----~----~------~----~------~--~---
