Eric, thanks very much for sharing. it's nice that you also provide the .org file on arXiv -- good marketing material! :) ah, and mention in the code appendix. it's very useful to have the .org file as a model of how to do various things.
i don't know if this is you, or is arXiv, but the ancillary files
("details" on the main page) claims to get .tar.gz (and, indeed,
downloads as a .tar.gz file) but is, in fact, an uncompressed .tar file.
cheers, Greg
