Boundary value ordinary differential equations (BVODEs) arise in a many applications and take on a variety of forms, including mixed order systems of nonliner equations with multi-point conditions. In this talk we will survey user interfaces currently provided by a number of BVODE solvers, and discuss and compare their capabilities and limitations. A central issue for code developers is reaching an effective compromise between clarity/ease-of-use and sophistication/flexibility. We will consider various examples of how user interface design decisions affect performance, supporting the discussion with numerical examples. It will be shown that some user interface decisions can be considered quite independently of performance, while others can have a dominant impact on the overall performance of the code.

MINISIMPOSIUM SESSION: 8. Software issues