Welcome to handyG’s documentation!

Generalised polylogarithms naturally appear in higher-order calculations of quantum field theories. We present handyG [6], a Fortran 90 library for the evaluation of such functions, by implementing the algorithm proposed by Vollinga and Weinzierl. This allows fast numerical evaluation of generalised polylogarithms with currently relevant weights, suitable for Monte Carlo integration.

Contents:

• Getting started
  • Obtaining the code
  • Installation using meson and ninja (recommended)
  • Installing using make
  • Usage in Fortran
  • Usage in Mathematica
• Notation
  • Multiple polylogarithms
  • Convergence properties
  • Shuffle algebra and trailing zeros
• The algorithm
  • Removal of trailing zeros
  • Making GPLs convergent
  • Evaluation of pending integrals
  • Increase rate of convergence
  • An example reduction
• Fortran reference guide
  • User-facing functions
  • Internal functions
  • Cache system
• Known Issues
  • Segmentation fault for arguments on the complex unit circle
  • GPLs with arguments close to one are not precise
  • Parallel builds are not supported
• Bibliography