Elliptic Curve latex method can create new latex commands by accident

[williamstein]

sage: K.<phi> = NumberField(x^2-x-1)
sage: a = phi
sage: E = EllipticCurve([0,0,a,27*a-43,-80*a+128])
sage: latex(E)
y^2 + \phiy = x^3 + \left(27 \phi - 43\right)x + \left(-80 \phi + 128\right) 

See the \phiy. Not good

Component: elliptic curves

Keywords: latex, sd51

Author: Frédéric Chapoton

Reviewer: Alex Ghitza

Merged: sage-5.12.beta2

Issue created by migration from https://trac.sagemath.org/ticket/12524

[kcrisman]

comment:1

This is not a problem about latex().

sage: var('phi,y')
(phi, y)
sage: phi*y
phi*y
sage: latex(phi*y)
\phi y

It's a problem in E.latex():

        elif b[2]:
            s += "+ %sy "%a[2]

Umm, yeah. Probably the intended use case is

sage: L.<z>=NumberField(x^2-x-1)
sage: b = z
sage: F = EllipticCurve([0,0,b,27*b-43,-80*b+128])
sage: latex(F)
y^2 + zy = x^3 + \left(27 z - 43\right)x + \left(-80 z + 128\right) 

So do you think that a one-whitespace change would fix this? (Actually, there are a few similar places.)

[kcrisman]

comment:2

Sorry, E._latex_().

[fchapoton]

comment:3

Attachment: trac_12524_latex_elliptic.patch.gz

Here is a proposal, needs review

[fchapoton]

Author: Frédéric Chapoton

[fchapoton]

Changed keywords from none to latex

[aghitza]

Reviewer: Alex Ghitza

[aghitza]

Changed keywords from latex to latex, sd51