LinApart2: efficient parallel partial fraction decomposition algorithm for denominators with polynomials of general degree
Levente Fekésházy, Oliver Schnetz
TL;DR
LinApart2 delivers a scalable univariate partial fraction decomposition method that handles denominators of arbitrary degree without explicit factorization by marrying a parallelizable Laurent-series approach with Galois-theoretic reductions. The paper details complex-analytic (complex-root) and algebraic (number-field) factorization perspectives, and provides Euclidean- and Galois-based strategies to compute expansion coefficients, including explicit examples. Benchmark results show substantial runtime and memory savings over Mathematica's $\Apart$ and over the Euclidean method, especially for high-complexity problems and when parallelization is leveraged, though some simple cases may still favor classical methods. The work provides an open-source Mathematica implementation, discusses performance trade-offs, and suggests future extensions and cross-language porting to maximize parallel efficiency in PFD tasks for quantum-field-theory computations and related symbolic workloads.
Abstract
We present LinApart2, a major update to the LinApart algorithm for univariate partial fraction decomposition. Unlike its predecessor, LinApart2 can handle denominators of arbitrary polynomial degree without explicit factorization, while retaining the efficiency and parallelizability of the Laurent series method. Benchmarks show substantial speedups in both runtime and memory usage compared to Mathematica's built-in routine Apart and to the Euclidean algorithm, enabling computations that were previously intractable.
