Function: quadregulator
Section: number_theoretical
C-Name: quadregulator
Prototype: Gp
Help: quadregulator(x): regulator of the real quadratic field of
discriminant x.
Doc: regulator of the quadratic field of positive discriminant $x$. Returns
an error if $x$ is not a discriminant (fundamental or not) or if $x$ is a
square. See also \kbd{quadclassunit} if $x$ is large.