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 b  
    12951295           
    12961296            sage: E2.local_data()
    12971297            []
     1298
     1299        See trac \#11347::
     1300
     1301            sage: K.<g> = NumberField(x^2 - x - 1)
     1302            sage: E = EllipticCurve(K,[0,0,0,-1/48,161/864]).integral_model().global_minimal_model(); E
     1303            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
     1304            sage: [(p.norm(), e) for p, e in E.conductor().factor()]
     1305            [(9, 1), (5, 1)]
     1306            sage: [(p.norm(), e) for p, e in E.discriminant().factor()]
     1307            [(9, 1), (-5, 2)]
    12981308        """
    12991309        if proof is None:
    13001310            import sage.structure.proof.proof
     
    13051315            raise ValueError, "global minimal models only exist in general for class number 1"
    13061316
    13071317        E = self.global_integral_model()
    1308         primes = self.base_ring()(self.discriminant()).support()
     1318        primes = E.base_ring()(E.discriminant()).support()
    13091319        for P in primes:
    13101320            E = E.local_data(P,proof).minimal_model()
    13111321        return E._reduce_model()