Function: nfbasistoalg
Section: number_fields
C-Name: basistoalg
Prototype: GG
Help: nfbasistoalg(nf,x): transforms the column vector x on the integral
basis into an algebraic number.
Doc: Given an algebraic number $x$ in the number field \var{nf}, transforms it
into \typ{POLMOD} form.
\bprog
? nf = nfinit(y^2 + 4);
? nf.zk
%2 = [1, 1/2*y]
? nfbasistoalg(nf, [1,1]~)
%3 = Mod(1/2*y + 1, y^2 + 4)
? nfbasistoalg(nf, y)
%4 = Mod(y, y^2 + 4)
? nfbasistoalg(nf, Mod(y, y^2+4))
%5 = Mod(y, y^2 + 4)
@eprog
This is the inverse function of \kbd{nfalgtobasis}.