Re: change variables in multivariant polynomials.

[Ariel Pacetti <apacetti@math.utexas.edu>]

>
> Usually the proper way to rename z to w in g is to do
> subst(g,z,w).
>
> changevar should never be used, it just does not work, it might
> even be removed completly in the future.
>

I had the following problem (some time ago): if I have a polynomial (let's
say in one variable) such that all the powers are even (multiples of 3, or
whatever), how can I make something like:

subst(g,x,x^(1/2)) ?

Clearly this expresion makes sence just formally, but pari tries to
compute "x^(1/2)" first. Is there a way to do this?
Cheers,

Ariel