Hi Robert, On Mar 12, 8:42 am, Robert Bradshaw <rober...@math.washington.edu> wrote: > > So, why is the corresponding operation not done in the second example? > > Because the ordering of variables is ambiguous. Should it be QQ > [a,x,x1,y1,z] or QQ[a,x1,x,y1,z]?
Good point, thank you! > sage: R = QQ['a,b,c,d'] > sage: S = QQ['x,y,z'] > > sage: all_vars = list(set(R.variable_names() + S.variable_names())) > sage: PolynomialRing(R.base_ring(), all_vars) > Multivariate Polynomial Ring in a, c, b, d, y, x, z over Rational Field Ok, this is what I thought. If there is no more direct / quicker way (some libsingular method that I ignored) then I will do so. Cheers, Simon --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---