This afternoon myself, a colleague and a new graduate spent 4 hours trying to debug a Mathcad sheet we were transcribing of an optical performance model that was failing because of unit scaling problems on angles. We were simply including dimensions checks as we went, but...
While there were other problems with the original documentation (e.g. using a function parameter as a variable of integration and it's own integral limit, but we were copying the functional form exactly) the crux of the problem was that Mathcad (this was V14 M030) still doesn't have spare dimensions to allow users to track key independent parameters. In this case it was the lack of the Angle dimension.
For those that don't know Angle, as a dimension, is
- The division of two independent orthogonal length measure (radius and arc are tangential!)
- a count of the number of times that Length has been canceled out of equations, while
- Length, which is 3d, has 3 orthogonal dimensions for dimensional analysis.
12 man hours to find a dimensional analysis scaling problem is not a great result for a tool that prides itself on its dimensional analysis capability.
Come on Mathcad, provide extra dimensions for such analysis checking (You've done currency, so it can be done!)
Philip.
