THE ALGORITHM FOR GENERATION OF CONNECTED CLOSED LINEAR GRAPHS FOR LATTICE-SPIN SYSTEMS
The paper presents the algorithm and subroutine GRGEN for generation of connected closed linear graphs utilized in perturbation expansions. Starting with polygons and subsequently choosing pairs of not directly connected vertices in already generated graphs, the algorithm consequently projects one vertex onto the other one in the pair, generating only topologically different graphs. This algorithm is independent of the choice of a specific model and lattice geometry. The procedure is written in the FORTRAN 77 language, and is available at the Poznań Supercomputing and Networking Center on the SGI Power Challenge XL supercomputer.