Function: nfnewprec
Section: number_fields
C-Name: nfnewprec
Prototype: Gp
Help: nfnewprec(nf): transform the number field data nf into new data using
 the current (usually larger) precision.
Doc: transforms the number field $\var{nf}$
 into the corresponding data using current (usually larger) precision. This
 function works as expected if \var{nf} is in fact a \var{bnf}, a \var{bnr}
 or a \var{rnf} (update structure to current precision). \emph{If} the original
 \var{bnf} structure was \emph{not} computed by \kbd{bnfinit(,1)}, then
 this may be quite slow and even fail: many
 generators of principal ideals have to be computed and the algorithm may
 fail because the accuracy is not sufficient to bootstrap the
 required generators and fundamental units.
Variant: See also \fun{GEN}{bnfnewprec}{GEN bnf, long prec} and
 \fun{GEN}{bnrnewprec}{GEN bnr, long prec}.
