# Ticket #11347: trac_11347.patch

File trac_11347.patch, 1.6 KB (added by William Stein, 12 years ago)
• ## sage/schemes/elliptic_curves/ell_number_field.py

```# HG changeset patch
# User William Stein <wstein@gmail.com>
# Date 1305659615 25200
# Node ID 380fa8eae288e260a5cbd827500df9f7e0fabb41
# Parent  04d8a77851fa24a8f7f8902b92e17bdbb5eccd4a
trac 11347 -- global_minimal_model function is sometimes wrong over number fields, when input model isn't integral

diff --git a/sage/schemes/elliptic_curves/ell_number_field.py b/sage/schemes/elliptic_curves/ell_number_field.py```
 a sage: E2.local_data() [] See trac \#11347:: sage: K. = NumberField(x^2 - x - 1) sage: E = EllipticCurve(K,[0,0,0,-1/48,161/864]).integral_model().global_minimal_model(); E Elliptic Curve defined by y^2 + x*y + y = x^3 + x^2 over Number Field in g with defining polynomial x^2 - x - 1 sage: [(p.norm(), e) for p, e in E.conductor().factor()] [(9, 1), (5, 1)] sage: [(p.norm(), e) for p, e in E.discriminant().factor()] [(9, 1), (-5, 2)] """ if proof is None: import sage.structure.proof.proof raise ValueError, "global minimal models only exist in general for class number 1" E = self.global_integral_model() primes = self.base_ring()(self.discriminant()).support() primes = E.base_ring()(E.discriminant()).support() for P in primes: E = E.local_data(P,proof).minimal_model() return E._reduce_model()