Sorry I sent the wrong counterexample:-) I deleted the post but you
were too fast. Now I submitted
the correct example.
Michel
On May 18, 4:33 pm, Martin Albrecht <[EMAIL PROTECTED]>
wrote:
> On Friday 18 May 2007 16:25, Michel wrote:
>
> > sage: Q=FractionField(QQ['x'])
> > sage: x=Q.gens()
> >
On Friday 18 May 2007 16:25, Michel wrote:
> sage: Q=FractionField(QQ['x'])
> sage: x=Q.gens()
> sage: V=Q['z']
> sage: z=V.gen()
> sage: x+z
Thats something different. x is a tuple as gens (note the plural) returns a
tuple.
Martin
--
name: Martin Albrecht
_pgp: http://pgp.mit.edu:11371/pks/
Now I could reproduce it.
sage: Q=FractionField(QQ['x','y'])
sage: x,y=Q.gens()
sage: V=Q['z']
sage: z=V.gen()
sage: x+z
---
Traceback (most recent call
last)
/home/vdbergh/sage-2.5/ in ()
/home/vdbergh/sage-
I could reproduce it!
sage: Q=FractionField(QQ['x'])
sage: x=Q.gens()
sage: V=Q['z']
sage: z=V.gen()
sage: x+z
: unsupported operand parent(s) for '+':
'' and 'Univariate Polynomial Ring in z over Fraction
Field of Univariate Polynomial Ring in x over Rational Field'
A missing automatic coercio
I am running the new libsingular and I get the following
sage: R = PolynomialRing(QQ, ['a','b','c','d','e'], 5)
sage: K = R.fraction_field()
sage: a,b,c,d,e = K.gens()
sage:
sage: ig = 12*a*e-3*b*d+c^2
sage: jg = 72*a*c*e+9*b*c*d-27*a*d^2-27*e*b^2-2*c^3
sage: hg = 8*a*c-3*b^2
sage: deltag = 4*ig^
