The deal.II finite element library: design, features, and insights

TL;DR

The paper presents deal.II, a comprehensive finite element library emphasizing generality, parallelism, and extensibility, along with insights into its design, features, and community-driven development over two decades.

Contribution

It details the design principles, advanced features, and community aspects of deal.II, highlighting its role as a versatile tool and educational platform in finite element analysis.

Findings

Successful implementation of distributed meshes and $hp$-adaptivity.

Support for complex geometries and matrix-free algorithms.

Insights into managing a large, diverse development community.

Abstract

deal.II is a state-of-the-art finite element library focused on generality, dimension-independent programming, parallelism, and extensibility. Herein, we outline its primary design considerations and its sophisticated features such as distributed meshes, $hp$-adaptivity, support for complex geometries, and matrix-free algorithms. But deal.II is more than just a software library: It is also a diverse and worldwide community of developers and users, as well as an educational platform. We therefore also discuss some of the technical and social challenges and lessons learned in running a large community software project over the course of two decades.