I know how to program so I don’t need that although numerical recipes are sometimes useful (Knuth’s mean in one pass my beloved).

I’m a solo hobbiest and not a formal education hater. There’s so much you only learn by following a good teacher (or at least only learn in a timely manner), reinventing the wheel is for experimental archeologists.

When you ask this the sort of people who have never read the art of computer programming (and it shows in their code believe me) tell you that you just need hands on the tools. Fingertip knowledge is essential sure, but hopefully there’s some more formally educated people here willing to share what reference material they’ve found the most useful.