I work with a few linear algebra types, so I decided a refresher was in order. Many years ago in college, the course I took worked up through idea of the Gram-Schmidt orthonomalizing process. This means I paid some of my dues, but stopping just shy of where the useful concepts start to kick in (processing data in a smaller/sparse basis, PCA, etc.). I selected this book because of its use of Python, and slowly worked through the content (however, I didn't code up the exercises). The FFT explanation is quite good. It was nice to see the author clearly state that determinants are good for making mathematical arguments, but are rarely useful in computation. That seems consistent with much in linear algebra, as it's not uncommon for me to be reading an algorithm paper that leads with a linear algebra explanation, but then goes on to say that it could never be computed using such an approach, and falls back on something more practical.