#15239: Nondegeneracy for subschemes of toric varieties
-------------------------------------+-------------------------------------
Reporter: vbraun | Owner:
Type: enhancement | Status: needs_work
Priority: major | Milestone: sage-6.4
Component: algebraic | Resolution:
geometry | Merged in:
Keywords: | Reviewers:
Authors: Volker Braun | Work issues:
Report Upstream: N/A | Commit:
Branch: | f885028d7ab463ff6e870ffa1ff61558304a5986
u/vbraun/is_nondegenerate | Stopgaps:
Dependencies: |
-------------------------------------+-------------------------------------
Comment (by kedlaya):
I think I see the problem with this example. In `restrict`, at some point
`Jac_patch` takes the value
{{{
Ideal (t0^12 - 2*t0^6*t3^2 + t3^4, 12*t0^11 - 12*t0^5*t3^2, 0, t0^10,
-4*t0^6*t3 + 4*t3^3) of Multivariate Polynomial Ring in t0, t1, t2, t3, t4
over Rational Field
}}}
but the third value in the tuple ought to be 0. The point is that
specializing to 0 does not commute with forming the Jacobian ideal when
you have a linear factor of a monomial, that is, the line
{{{
Jac_patch = Jac.subs(patch)
}}}
is incorrect.
--
Ticket URL: <http://trac.sagemath.org/ticket/15239#comment:11>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
