1 | initial version |
The three polynomials used to describe the particular ideal in your example are a Groebner basis for it.
sage: R.<x,y,z> = PolynomialRing(QQ,3)
sage: I = Ideal([x^2+y+z-1,x+y^2+z-1,x+y+z^2-1])
sage: B = I.groebner_basis(); B
[x^2 + y + z - 1, y^2 + x + z - 1, z^2 + x + y - 1]
However, the ideal and its Groebner basis are not the same. Check their type and their parent.
sage: type(I)
<class 'sage.rings.polynomial.multi_polynomial_ideal.MPolynomialIdeal'>
sage: I.parent()
Monoid of ideals of Multivariate Polynomial Ring in x, y, z over Rational Field
sage: type(B)
<class 'sage.rings.polynomial.multi_polynomial_sequence.PolynomialSequence_generic'>
sage: B.parent()
Category of sequences in Multivariate Polynomial Ring in x, y, z over Rational Field
Also, if you check the documentation for groebner_basis
, you
will find examples of families of polynomials who are not a
Groebner basis for the ideal they generate.
sage: I.groebner_basis?