Function: ellztopoint
Section: elliptic_curves
C-Name: pointell
Prototype: GGp
Help: ellztopoint(E,z): coordinates of point P on the curve E corresponding
 to the complex number z.
Doc:
 $E$ being an \var{ell} as output by
 \kbd{ellinit}, computes the coordinates $[x,y]$ on the curve $E$
 corresponding to the complex number $z$. Hence this is the inverse function
 of \kbd{ellpointtoz}. In other words, if the curve is put in Weierstrass
 form, $[x,y]$ represents the \idx{Weierstrass $\wp$-function} and its
 derivative. If $z$ is in the lattice defining $E$ over $\C$, the result is
 the point at infinity $[0]$.
