Analysis and Efficient Sylvester-Based Implementation of a Dimension-Split ETD2RK Scheme for Multidimensional Reaction-Diffusion Equations

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Sarumi, Ibrahim O.
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908757254995968
author Sarumi, Ibrahim O.
author_facet Sarumi, Ibrahim O.
contents We propose and analyze a second-order, dimension-split exponential time differencing Runge--Kutta scheme (ETD2RK-DS) for multidimensional reaction--diffusion equations in two and three spatial dimensions. Under mild assumptions on the nonlinear source term, we establish uniform stability bounds and prove second-order temporal convergence for the underlying dimension-split scheme. To enable efficient implementation, we employ Padé approximations of the matrix exponential, converting each required matrix-exponential--vector product into the solution of a shifted linear system. A convergence analysis of the resulting Padé-based ETD2RK-DS formulation is provided. We derive explicit and reproducible tensor-slicing and reshaping algorithms that realize the dimension-splitting strategy, decomposing multidimensional systems into collections of independent one-dimensional problems. This leads to a reduction of the dominant per-time-step computational cost from $\mathcal{O}(m^3)$ to $\mathcal{O}(m^2)$ in two dimensions and from $\mathcal{O}(m^5)$ to $\mathcal{O}(m^3)$ in three dimensions when compared with banded LU solvers for the unsplit problem, where $m$ denotes the number of grid points per spatial direction. Furthermore, we develop a Sylvester-equation reformulation of the resulting one-dimensional systems, enabling a highly efficient spectral implementation based on reusable eigendecompositions, matrix--vector multiplications, and Hadamard divisions. Numerical experiments in two and three dimensions, including a coupled FitzHugh--Nagumo system, confirm the second-order temporal accuracy, stability of the underlying scheme, and scalability of the proposed ETD2RK-DS framework, as well as the substantial computational advantages of the Sylvester-based implementation over classical LU-based solvers.
format Preprint
id arxiv_https___arxiv_org_abs_2601_06849
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Analysis and Efficient Sylvester-Based Implementation of a Dimension-Split ETD2RK Scheme for Multidimensional Reaction-Diffusion Equations
Sarumi, Ibrahim O.
Numerical Analysis
65M06, 65L20, 65M20, 65F60, 65L05
We propose and analyze a second-order, dimension-split exponential time differencing Runge--Kutta scheme (ETD2RK-DS) for multidimensional reaction--diffusion equations in two and three spatial dimensions. Under mild assumptions on the nonlinear source term, we establish uniform stability bounds and prove second-order temporal convergence for the underlying dimension-split scheme. To enable efficient implementation, we employ Padé approximations of the matrix exponential, converting each required matrix-exponential--vector product into the solution of a shifted linear system. A convergence analysis of the resulting Padé-based ETD2RK-DS formulation is provided. We derive explicit and reproducible tensor-slicing and reshaping algorithms that realize the dimension-splitting strategy, decomposing multidimensional systems into collections of independent one-dimensional problems. This leads to a reduction of the dominant per-time-step computational cost from $\mathcal{O}(m^3)$ to $\mathcal{O}(m^2)$ in two dimensions and from $\mathcal{O}(m^5)$ to $\mathcal{O}(m^3)$ in three dimensions when compared with banded LU solvers for the unsplit problem, where $m$ denotes the number of grid points per spatial direction. Furthermore, we develop a Sylvester-equation reformulation of the resulting one-dimensional systems, enabling a highly efficient spectral implementation based on reusable eigendecompositions, matrix--vector multiplications, and Hadamard divisions. Numerical experiments in two and three dimensions, including a coupled FitzHugh--Nagumo system, confirm the second-order temporal accuracy, stability of the underlying scheme, and scalability of the proposed ETD2RK-DS framework, as well as the substantial computational advantages of the Sylvester-based implementation over classical LU-based solvers.
title Analysis and Efficient Sylvester-Based Implementation of a Dimension-Split ETD2RK Scheme for Multidimensional Reaction-Diffusion Equations
topic Numerical Analysis
65M06, 65L20, 65M20, 65F60, 65L05
url https://arxiv.org/abs/2601.06849