Hi Martin, On Aug 1, 4:09 pm, Martin Albrecht <m...@informatik.uni-bremen.de> wrote: > sage: R.<a111,a112,a121,a122,b111,b112,b211,b212,c111,c112> = > BooleanPolynomialRing(order='lex') > sage: I=(a111 * b111 * c111 + a112 * b112 * c112 - 1 , a111 * b211 * c111 + > ....: a112 * b212 * c112 - 0 , a121 * b111 * c111 + a122 * b112 * c112 , > ....: a121 * b211 * c111 + a122 * b212 * c112 - 1)*R > > sage: I.groebner_basis() > [a111 + b212, a112 + b211, a121 + b112, a122 + b111, c111 + 1, c112 + 1]
Why do I get a different result? Bug in PolyBoRi, a changed interpretation of the meaning of "lex" (I use sage 4.1, and you?), or a misprint on my side (but so far I can't see any)? sage: RB.<a111,a112,a121,a122,b111,b112,b211,b212,c111,c112>=BooleanPolynomialRing (order='lex') sage: IB = (a111 * b111 * c111 + a112 * b112 * c112 - 1 , a111 * b211 * c111 + a112 * b212 * c112 - 0 , a121 * b111 * c111 + a122 * b112 * c112 , a121 * b211 * c111 + a122 * b212 * c112 - 1)*RB sage: GB = IB.groebner_basis() sage: GB [a111 + b212, a112 + b211, a121 + b112, a122 + b111, b111*b112 + b111 + b112 + 1, b111*b211 + b111 + b211 + 1, b111*b212 + b112*b211 + 1, b112*b212 + b112 + b212 + 1, b211*b212 + b211 + b212 + 1, c111 + 1, c112 + 1] It seems that your answer is not a Groebner Basis: sage: G = Sequence([a111 + b212, a112 + b211, a121 + b112, a122 + b111, c111 + 1, c112 + 1]) sage: [p.reduce(G) for p in GB] [0, 0, 0, 0, b111*b112 + b111 + b112 + 1, b111*b211 + b111 + b211 + 1, b111*b212 + b112*b211 + 1, b112*b212 + b112 + b212 + 1, b211*b212 + b211 + b212 + 1, 0, 0] sage: [p.reduce(GB) for p in G] [0, 0, 0, 0, 0, 0] 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 -~----------~----~----~----~------~----~------~--~---
