Ok, I will do the upstream-report (Singular trac at http://www.singular.uni-kl.de:8002/trac/newticket)
John Cremona: [...] which I'm sure has been reported before. > I could not find a corresponding ticket in sage trac and cannot currently login. Could someone open a that ticket in sage-trac if necessary? Jack Am Montag, 27. Januar 2014 15:15:08 UTC+1 schrieb Peter Bruin: > > Hello, > > > I'm a bit confused about Sage's answer if Ideal(1) is prime. > > > > R.<x,y>= QQ[] > > I = Ideal(R(1)) > > I.is_prime() > > > > Sage (5.11, not only) says yes, > > conflicting to the definition, > > http://en.wikipedia.org/wiki/Prime_ideal > > Has somebody an expanation of this behaviour? > > The example Singular session below suggests that the problem lies in > Singular (I'm not too familiar with Singular, but I think the answers > should all be the same, and only primdecSY(J) seems to be correct). > > Peter > > > $ sage -singular > SINGULAR / > Development > A Computer Algebra System for Polynomial Computations / version > 3-1-5 > 0< > by: W. Decker, G.-M. Greuel, G. Pfister, H. Schoenemann \ Jul 2012 > FB Mathematik der Universitaet, D-67653 Kaiserslautern \ > > LIB "primdec.lib" > (...) > > ring R = 0, (x, y), dp; > > ideal I = 1; > > primdecSY(I); > [1]: > [1]: > _[1]=1 > [2]: > _[1]=1 > > primdecGTZ(I); > [1]: > [1]: > _[1]=1 > [2]: > _[1]=1 > > ideal J = x, x + 1; > > primdecSY(J); > empty list > > primdecGTZ(J); > [1]: > [1]: > _[1]=1 > [2]: > _[1]=1 > > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/groups/opt_out.
