Implementing an Algorithm for Solving Block Hessenberg Systems

Abstract

This paper describes the implementation of a recursive descent method for solving block Hessenberg systems. Although the algorithm is conceptually simple, its implementation in C (a natural choice of language given the recursive nature of the algorithm and its data) is nontrivial. Particularly important is the balance between ease of use, computational efficiency, and flexibility. (Also cross-referenced as UMIACS-TR-94-70)