PeaPods

A Python library for simulating Ising spin systems with modern Monte Carlo methods. The core simulation loop is written in Rust (via PyO3) for performance, with a thin Python wrapper for ease of use.

Features

• Ising ferromagnets and spin glasses on periodic Bravais lattices (hypercubic, triangular, or any custom neighbor offsets)
• Arbitrary, bimodal (±J), or Gaussian coupling distributions
• Multiple replicas with overlap statistics for spin glass order parameters
• Metropolis, Gibbs, Swendsen-Wang, Wolff, parallel tempering, Houdayer ICM, Jörg, and CMR algorithms

Quickstart

import numpy as np
from peapods import Ising

# 2D ferromagnet with cluster updates and parallel tempering
model = Ising((32, 32), temperatures=np.linspace(1.5, 3.0, 32), n_replicas=2)
model.sample(n_sweeps=5000, sweep_mode="metropolis",
             cluster_update_interval=1, pt_interval=1)
print(model.binder_cumulant)

Installation

uv pip install peapods

Pre-built wheels are available for Linux (x86_64, aarch64), macOS (Intel, Apple Silicon), and Windows (x86_64).