# invariant_theory package

I am trying to follow the tutorial on the invariant_theory package: http://www.sagemath.org/doc/reference...

I asked sage to execute the first example:

sage: R.<x,y> = QQ[]

sage: q = x^4 + y^4

sage: quartic = invariant_theory.binary_quartic(q); quartic

But received the following error: Traceback (click to the left of this block for traceback) ... NameError: name 'invariant_theory' is not defined

I have the newest version of sage installed. What's going wrong here?

Exactly what version of Sage do you have installed? You need 5.7 or later to use this feature.