Until recently, the testing of ODE/DAE solvers has been limited to comparing software. The complex development of adaptive software from a mathematically specified method entails constructing control structures and objectives, selecting termination criteria for iterative methods, choosing norms and many more decisions. Most software constructors have taken a heuristic approach to these design choices, invalidating the process of deducing from software comparisons that one method is better than another. We argue that ODE/DAE software can be constructed and analyzed by proven, ``standard'' scientific techniques instead of heuristics. The goal is reproducibility as well as improved software quality. We discuss several issues which are of importance both from the point of view of software design and software/method evaluation.

MINISIMPOSIUM SESSION: 17. Software isues in ODEs