It might work if you try coercing f = B[0] first into
R2.<x,y> = PolynomialRing(CC, 2, 'xy')
then applying factor or whatever to R2(f). I haven't tried it with your
problem but that general idea has worked for me in similar situations.
On Tue, Mar 25, 2008 at 5:18 AM, continuum121 <[EMAIL PROTECTED]> wrote:
>
> Hi!
>
> I have a problem. Here is its formulation. I work in some polynomial
> ring - lets say
> R,(x,y) = PolynomialRing(QQ, 2, 'xy', order='lex').objgens()
> and consider ideal in R
> I = ideal(x+y^3-2,y+x^3-2)
> then I calculate grobner basis for ideal I
> B = I.groebner_basis(); B
> B[0] is univariate polynomial. Here the real problem begins. I would
> like to get real roots of polynomial B[0]. I can do B[0].factor() but
> it gives only part of information us factorization is over Q[x,y].
> More intuitive way for me is to treat it symbolicly. I want to write
> solve(B[0] == 0, x) but it doesn't work us function solve() needs
> symbolic object and gets boolean expression.
>
> The question is: how to find real roots for polynomial object either
> symbolicly (more desired) or numericly?
>
> The only solution I have figured out is as follow. I write
> x,y=var('x,y') and then declare f = ... (here I copy paste B[0]) but
> it's not the way I want do this.
>
> Does anyone know how to solve it?
>
> Best regards
>
> >
>
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