Hmm, I thought this was a bug, but the following works: sage: R = ZZ['u', 'v'].fraction_field()
sage: EllipticCurve(R, [1,1]) Elliptic Curve defined by y^2 = x^3 + x +1 over Fraction Field of Polynomial Ring in u, v over Integer Ring Maybe the previous post shouldn't work, because it's a ring, not a field? There are some algorithms that use the discrepancy, so whatever happens the situation should be clarified. Nick On Feb 6, 8:32 pm, "Nick Alexander" <[EMAIL PROTECTED]> wrote: > We still have problems coercing constants into polynomial rings, when > the constants are themselves in interesting rings... > > sage: R = ZZ['u', 'v'] > > sage: EllipticCurve(R, [1,1]) > --------------------------------------------------------------------------- > <type 'exceptions.TypeError'> Traceback (most recent call > last) > > /Users/nalexand/<ipython console> in <module>() > > /Users/nalexand/Devel/sage/local/lib/python2.5/site-packages/sage/ > schemes/elliptic_curves/constructor.py in EllipticCurve(x, y) > 97 return > ell_finite_field.EllipticCurve_finite_field(x, y) > 98 else: > ---> 99 return ell_generic.EllipticCurve_generic(x, y) > 100 > 101 if isinstance(x, str): > > /Users/nalexand/Devel/sage/local/lib/python2.5/site-packages/sage/ > schemes/elliptic_curves/ell_generic.py in __init__(self, ainvs, extra) > 95 a1, a2, a3, a4, a6 = ainvs > 96 f = y**2*z + (a1*x + a3*z)*y*z \ > ---> 97 - (x**3 + a2*x**2*z + a4*x*z**2 + a6*z**3) > 98 plane_curve.ProjectiveCurve_generic.__init__(self, PP, > f) > 99 if K.is_field(): > > /Users/nalexand/element.pyx in element.RingElement.__mul__() > > /Users/nalexand/element.pyx in element.bin_op_c() > > <type 'exceptions.TypeError'>: unsupported operand parent(s) for '*': > 'Polynomial Ring in u, v over Integer Ring' and 'Polynomial Ring in x, > y, z over Polynomial Ring in u, v over Integer Ring' > > Nick --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
