This paper on "Object-Oriented Finite Element Programming Languages, Symbolic Derivations, Reasoning Capabilities" was presented at the NAFEMS World Congress on Design, Simulation & Optimisation: Reliability & Applicability of Computational Methods - 9-11 April 1997, Stuttgart, Germany.

Abstract

The object-oriented approach provides an appropriate context for an integrated description of finite element related techniques within a single unified environment, combining symbolic and numerical manipulations, graphics and expertise.
The research work presented in this paper started about ten years ago with the development of a small finite element package written in Smalltalk. The tremendous advantages of the novel approach, which leads to smaller programs and easier code maintenance and extension, was immediately apparent, but the performance (Smalltalk is interpreted) was unsatisfactory. Newer developments in C⁺⁺ led to more efficient codes but object-orientedness was lost to a large extent : until the occurrence of Java which seems to retain the most essential positive aspects of Smalltalk and C⁺⁺ .
A different research direction was undertaken more recently, which consists in developing symbolic manipulation tools which facilitate the derivation of finite element models. The new toolbox manipulating symbolic terms, expressions, integrals and functionals, provides now the means for the implementation of a new field theory in a matter of hours.
Finally, further enhancement of the environment was examined using logic programming techniques. The paper discusses the key aspects of all these developments.