Number field arithmetic in Pari/gp
I would like to do number field arithmetic in Pari. To be more precise, I would like let Pari do the following job as Sage does,
K.<a> = NumberField(f(x)) L.<b> = NumberField(g(x))
where f(x), g(x) are irreducible polynomials over the rational. I would like to do arithmetic with a,b. This is easily done in Sage. How can I do this by Pari?