Function: hyperellratpoints
Section: elliptic_curves
C-Name: hyperellratpoints
Prototype: GGD0,L,
Help: hyperellratpoints(X,h,{flag=0}): X being a nonsingular hyperelliptic
 curve given by an rational model, return a vector containing the affine
 rational points on the curve of naive height less than h.
 If fl=1, stop as soon as a point is found.
 X can be given either by a squarefree polynomial P such that
 X:y^2=P(x) or by a vector [P,Q] such that X:y^2+Q(x)y=P(x) and Q^2+4P is
 squarefree.
Doc: $X$ being a nonsingular hyperelliptic curve given by an rational model,
 return a vector containing the affine rational points on the curve of naive
 height less than $h$. If $\fl=1$, stop as soon as a point is found; return
 either an empty vector or a vector containing a single point.

 $X$ is given either by a squarefree polynomial $P$ such that $X: y^{2}=P(x)$
 or by a vector $[P,Q]$ such that $X: y^{2}+Q(x)\*y=P(x)$ and $Q^{2}+4\*P$ is
 squarefree.

 \noindent The parameter $h$ can be

 \item an integer $H$: find the points $[n/d,y]$ whose abscissas $x = n/d$ have
 naive height (= $\max(|n|, d)$) less than $H$;

 \item a vector $[N,D]$ with $D\leq N$: find the points $[n/d,y]$ with
 $|n| \leq N$, $d \leq D$.

 \item a vector $[N,[D_{1},D_{2}]]$ with $D_{1}<D_{2}\leq N$  find the points
 $[n/d,y]$ with $|n| \leq N$ and $D_{1} \leq d \leq D_{2}$.
