Under what circumstances were you violating the rule? It would be good to know in case it seems unecessarily restrictive.

Volume space shows a good example of why "violation" might be desired. A single slice dataset might get written as 2-D (with nz=0). But perhaps that would cause a "volumetric" program to fail to read it, when it would otherwise be okay (if nz were set to 1).

On the flip side, part of the question may be with respect to memory allocation. If the data is 4-D one might allocate 3 levels of pointers. But if the highest dimension size is 1, that is an unneeded complication to the coding.

Should we ponder this, or stick with the current wording, in which case I can make an update to the library? Does anyone else want to chime in?

- rick