English

A direct fast FFT-based implementation for high order finite element method on rectangular parallelepipeds for PDE

Numerical Analysis 2026-01-05 v1 Numerical Analysis

Abstract

We present a new direct logarithmically optimal in theory and fast in practice algorithm to implement the high order finite element method on multi-dimensional rectangular parallelepipeds for solving PDEs of the Poisson kind. The key points are the fast direct and inverse FFT-based algorithms for decomposition in eigenvectors of the 1D eigenvalue problems for the high order FEM. The algorithm can further be used for numerous applications, in particular, to implement the high order finite element methods for various time-dependent PDEs.

Keywords

Cite

@article{arxiv.1609.07758,
  title  = {A direct fast FFT-based implementation for high order finite element method on rectangular parallelepipeds for PDE},
  author = {Alexander Zlotnik and Ilya Zlotnik},
  journal= {arXiv preprint arXiv:1609.07758},
  year   = {2026}
}

Comments

7 pages, 1 figure, 1 table

R2 v1 2026-06-22T16:00:33.299Z