Re: Getting the variable of a polynomial

[Jeroen Demeyer <jdemeyer@cage.ugent.be>]

Ariel Pacetti wrote:
> We wrote (with Fernando Villegas) a stupid function for doing this (and 
> some easy polynomials computations). You can found them in the web page:
>
> http://www.ma.utexas.edu/users/villegas/cnt/cnt-frames.html
>
> (the routine name is polynomials). Most routine are documented. This 
> specific one is "variables" (you can modify the routine or the name)
>
> ? variables(x^2-t)
> %1 = [t, x]

Thanks for the suggestion, but I don't know if this is what I want.  I 
just want the main variable of a t_POL.

For instance, I want to implement polfrobenius(), which raises all 
coefficients of a polynomial to a certain power.  The idea would be to 
convert the polynomial to a vector using Vec(), then raise all elements 
to the desired power, then convert back to a polynomial using Pol(). 
This works fine, except that the variable changes.