Function: elltatepairing
Section: elliptic_curves
C-Name: elltatepairing
Prototype: GGGG
Help: elltatepairing(E,P,Q,m): computes the Tate pairing of the two points
 P and Q on the elliptic curve E. The point P must be of m-torsion.
Doc: Let $E$ be an elliptic curve defined over a finite field $k$
 and $m \geq 1$ be an integer. This function computes the (nonreduced) Tate
 pairing of the points $P$ and $Q$ on $E$, where $P$ is an $m$-torsion point.
 More precisely, let $f_{m,P}$ denote a Miller function with divisor $m[P] -
 m[O_{E}]$; the algorithm returns $f_{m,P}(Q) \in k^{*}/(k^{*})^{m}$.
