That's great! I have made a few attempts to learn PDL, and while I've been able to do a few things, I think going through this exercise will help me solidify some ideas.

Once the TODOs get fleshed out, I think this should be added to the Tutorials. I would suggest wrapping the code/answers in <spoilers> tags for the final version of the tutorial. Also, for (at least some of) the "n/a" or numpy-specific questions, it may be possible to convert them to perl equivalents.