CHAPLIN - Complex Harmonic Polylogarithms in Fortran

TL;DR

This paper introduces CHAPLIN, a Fortran library that efficiently evaluates harmonic polylogarithms up to weight four for complex arguments using series expansions, enabling fast and reliable computations.

Contribution

The paper presents a novel Fortran library that reduces harmonic polylogarithms to basis functions for rapid numerical evaluation up to weight four.

Findings

Fast and reliable numerical evaluation of harmonic polylogarithms up to weight four.

Implementation based on series expansions for complex arguments.

Applicable to various scientific computations requiring polylogarithm evaluations.

Abstract

We present a new Fortran library to evaluate all harmonic polylogarithms up to weight four numerically for any complex argument. The algorithm is based on a reduction of harmonic polylogarithms up to weight four to a minimal set of basis functions that are computed numerically using series expansions allowing for fast and reliable numerical results.