Let $f:\mathbb{C}\to \mathbb{C}$ be an elliptic function, with lattice $L={\omega }_1\mathbb{Z}+{\omega }_2\mathbb{Z}$. Let $z_0\in \mathbb{C}$, then we have a tuple $(z_0,z_0+{\omega }_1,z_0+{\omega }_1+{\omega }_2,z_0+{\omega }_2)$. Let $P^{\prime }$ be the convex hull of these points, which is a parallelogram. We need to delete two sides, since $f$ is doubly periodic and we don't want repeated points mod $L$, and we choose the sides $(z_0+{\omega }_1+{\omega }_2,z_0+{\omega }_2)$ and $(z_0,z_0+{\omega }_2)$. We say that this $P$ is now a fundamental domain. Furthermore:

1. $P$ is positively oriented 1;;if $im({\omega }_2/{\omega }_1)>0$.
2. $P$ is called a cell if 1;; There are no poles on the boundary of $P$