I = gfanLatticeIdeal L
This method computes the generators for the lattice ideal. The input should be a list of points that generate the lattice.

The lattice ideal of a free abelian subgroup $L$ of $\mathbb Z^n$ is the ideal generated by $ \mathbf{x}^{\alpha^+}  \mathbf{x}^{\alpha^}$ for $\alpha =\alpha^+  \alpha^ \in L$.
gfan Documentation
This program computes the lattice ideal of a lattice. The input is a list of generators for the lattice.
Options:
t:
Compute the toric ideal of the matrix whose rows are given on the input instead.
convert:
Does not do any computation, but just converts the vectors to binomials.
The object gfanLatticeIdeal is a method function with options.