Function: nfhnf
Section: number_fields
C-Name: nfhnf
Prototype: GG
Help: nfhnf(nf,x): if x=[A,I], gives a pseudo-basis of the module sum A_jI_j
Doc: given a pseudo-matrix $(A,I)$, finds a
 pseudo-basis in \idx{Hermite normal form} of the module it generates.
Variant: Also available:

 \fun{GEN}{rnfsimplifybasis}{GEN bnf, GEN x} simplifies the pseudo-basis
 given by $x = (A,I)$. The ideals in the list $I$ are integral, primitive and
 either trivial (equal to the full ring of integer) or non-principal.