ALF — Algorithms for Lattice Fermions

Welcome to the ALF wiki! This is the practical companion to the formal documentation (PDF). Here you’ll find installation guides, tutorials, parameter tuning advice, and developer resources.

Project website: https://alf.physik.uni-wuerzburg.de/

• ALF Wiki
• Installation
• Quick Start
  • Running with pyALF
  • Running without pyALF
• Configuration
• Production Run Cycle
• Writing a New Model
  • Predefined Lattices
  • Predefined Observables
• Analysis Tools
  • HDF5 Output Format
  • Bin Conversion
  • Analytic Continuation
• Tuning and Best Practices
  • Discretization
  • Stabilization Parameters
  • HMC Parameters
  • Tempering
• Running on Clusters
• Troubleshooting and FAQ
• Developer Guide
  • Test Suite
  • Code Architecture
  • Release Process
• Glossary

Getting Started¶

• Installation — Build ALF from source on macOS or Linux

• Quick Start — Run your first simulation in minutes

  • Running with pyALF — Python interface (recommended for new users)

  • Running without pyALF — Direct Fortran workflow

• Configuration — Compiler options, MPI, HDF5, and build modes

Using ALF¶

• Production Run Cycle — Systematic study of an existing model from setup to results

• Writing a New Model — Implement your own Hamiltonian using the ALF framework

  • Predefined Lattices — Square, Honeycomb, Bilayer, Triangular, Kagome, and more

  • Predefined Observables — Equal-time and time-displaced measurements

• Analysis Tools — Post-processing, binning, and analytic continuation

  • HDF5 Output Format — Structure of simulation output files

  • Bin Conversion — Converting and rebinning data

  • Analytic Continuation — Maximum entropy methods

Tuning & Best Practices¶

Practical advice on choosing simulation parameters:

• Tuning and Best Practices — Overview and general guidance

  • Discretization — Dtau and Trotter error tradeoffs

  • Stabilization Parameters — Nwrap and numerical stabilization

  • HMC Parameters — Step size, leap-frog steps, mass matrix

  • Tempering — Parallel tempering configuration

Operations¶

• Running on Clusters — Job scripts and tips for HPC systems

• Troubleshooting and FAQ — Common issues and solutions

Development¶

• Developer Guide — Contributing to ALF

  • Test Suite — Running and writing tests

  • Code Architecture — Module structure and data flow

  • Release Process — Versioning and release cycle

• Glossary — QMC terminology and ALF-specific concepts