Function: idealappr
Section: number_fields
C-Name: idealappr0
Prototype: GGD0,L,
Help: idealappr(nf,x,{flag}): x being a fractional ideal, gives an element
 b such that v_p(b)=v_p(x) for all prime ideals p dividing x, and v_p(b)>=0
 for all other p; x may also be a prime ideal factorization with possibly
 zero exponents. flag is deprecated (ignored), kept for backward compatibility.
Doc: if $x$ is a fractional ideal
 (given in any form), gives an element $\alpha$ in $\var{nf}$ such that for
 all prime ideals $\goth{p}$ such that the valuation of $x$ at $\goth{p}$ is
 non-zero, we have $v_{\goth{p}}(\alpha)=v_{\goth{p}}(x)$, and
 $v_{\goth{p}}(\alpha)\ge0$ for all other $\goth{p}$.

 The argument $x$ may also be given as a prime ideal factorization, as
 output by \kbd{idealfactor}, but allowing zero exponents.
 This yields an element $\alpha$ such that for all prime ideals $\goth{p}$
 occurring in $x$, $v_{\goth{p}}(\alpha) = v_{\goth{p}}(x)$;
 for all other prime ideals, $v_{\goth{p}}(\alpha)\ge0$.

 flag is deprecated (ignored), kept for backward compatibility.

Variant: Use directly \fun{GEN}{idealappr}{GEN nf, GEN x} since \fl is ignored.