Elliptic integrals

It would be nice to have complete and incomplete elliptic integrals of the first and second kind available.

OK, I've figured out that

    E(k) = (pi/2)*hyperG2F1(-1/2, 1/2, 1, k^2)

and

    K(k) = (pi/2)*hyperG2F1(1/2, 1/2, 1, k^2).

Maybe not the most efficient implementation, but it will do the job.