On Wed, Sep 9, 2009 at 7:14 AM, VictorMiller <[email protected]> wrote: > > I just ran the following on sagenb.org (so the latest release): > > PP.<x,y,z,w> = ProjectiveSpace(3,QQ) > f = x^3 + y^3 + z^3 + w^3 > R = f.parent() > I = [f] + [f.derivative(zz) for zz in PP.gens()] > V = PP.subscheme(I) > V.irreducible_components() > > The output is: > > > > [ > Closed subscheme of Projective Space of dimension 3 over Rational > Field > defined by: > w > z > y > x > ] > > [ > Closed subscheme of Projective Space of dimension 3 over Rational > Field defined by: > w > z > y > x > ] > > > I think that the problem is that normally Proj(R) is defined to be all > prime ideals that do not contain > > sum_{d > 0} S_d > > where R is a graded ring graded by non-negative integers, and S_d is > the ideal generated by homogeneous elements of degree d. I glanced at > irreducible_components and it just returns all of the prime ideals > coming from the primary decomposition. In the case that the ambient > scheme is projective, it should exclude some. > > Victor
Thanks! This is now: http://trac.sagemath.org/sage_trac/ticket/6920 And, see you in a few days at Sage Days 17! William --~--~---------~--~----~------------~-------~--~----~ 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-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
