Implementation issues for three-dimensional vector FEM programs

Theoretical and practical issues that impact on the development of (especially) three-dimensional vector finite-element (FEM) programs are discussed. The theory of vector elements is briefly reviewed, and some troublesome aspects are highlighted: in particular, the interpretation of the degrees of freedom. The choice of element shape is briefly addressed, as is the evaluation of the elemental matrices. Several useful references are provided in this context. Data structures appropriate for a three-dimensional code are outlined, as is the issue of establishing mesh interconnectivity. The topics of mesh generation and linear algebra are very briefly considered. The paper concludes with some comments on post-processing, in particular, the computation of fields within the FE mesh.