The Goresky-Kottwitz-MacPherson (GKM) graph is a combinatorial analogue of a compact connected symplectic manifold with a Hamiltonian action of a compact torus. This graph has been intensively studied by Guillemin and Zara, who discovered analogues in graph theory of classical results such as: symplectic reduction and "quantization and reduction commute.'' In this paper, we describe the implementation of algorithms illustrating their results.
"Effective reduction of Goresky-Kottwitz-MacPherson graphs." Experiment. Math. 14 (2) 133 - 144, 2005.