Function: _header_hyperelliptic_curves
Class: header
Section: hyperelliptic_curves
Doc:
 \section{Hyperelliptic curves}
 A hyperelliptic curve $C$ can be given either by a squarefree polynomial
 $P$ such that $C: y^{2} = P(x)$ or by a vector $[P,Q]$ such that $C: y^{2} +
 Q(x)\*y = P(x)$ and $Q^{2}+4\*P$ is squarefree.

 A few functions, sharing the prefix \kbd{genus2}, are specific to the
 genus~$2$ case ($Q^{2} + 4\*P$ has degree 5 or 6).

