Will definitely check out this book. I recently learned some R and just used it for a very specific type of programming task (Morphometrics for a biologist).

Very happy to have learned a new language outside of my normal Python/PHP/JavaScript realm. If you're looking to learn a new language that is a bit different than what you might be used to and want to brush up on some math, I highly recommend playing with R for a while.

Another book to checkout is O'Reilly's Data Analysis with Open Source Tools, which has sections on R and NumPy.