-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi all,
I think I found a bug, or use singular in sage in the wrong way: sage: R = QQ['x1,x2,x3,x4,x5'] sage: (x1,x2,x3,x4,x5) = R.gens() sage: I = (x1*x4^2 - x2*x5^2, x1^3*x3^3 - x4^2*x2^4, x2*x4^8 - x3^3*x5^6)* R sage: I.quotient(x3*R) == I True sage: J = I + x1^2*R sage: J.quotient(x3*R) == J False sage: However, I think there is a theorem that guarantees that the last line is true. A quick computation in pure singular shows that it is in fact the case. Here is how to do it in singular, note that sometimes you explicitly have to request standard bases or singular messes up things. Could it be related to this ? ring R = 0,(x1,x2,x3,x4,x5),dp; ideal I = x1*x4^2-x2*x5^2, x1^3*x3^3-x2^4*x4^2, x2*x4^8-x3^3*x5^6; std(quotient(I,x3)) std(I) *** Here I compare the output manually since I dont know hot to compare ideals in singular **** ideal J = I + x1^2 std(quotient(J,x3)) std(J) Thanks Tom -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkk1pG8ACgkQrpEWPKIUt7N9LgCeIBpOWVLxwBuA+qpeTLylpjpv tkAAn3AcRNc8LV/1yPwllVpCQMOY/l7K =AVGl -----END PGP SIGNATURE----- --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sage-devel" group. 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-devel?hl=en -~----------~----~----~----~------~----~------~--~---
