Calculation of partition function for zero-field planar Ising models, based on code from https://github.com/ValeryTyumen/planar_ising.
Implementation of the paper "Inference and Sampling of K33-free Ising Models", Valerii Likhosherstov, Yury Maximov, Michael Chertkov. https://arxiv.org/abs/1812.09587, accepted to ICML 2019.