(3rd Edition) by Press et al., is written in C++ but remains the definitive theoretical reference for the algorithms. PDF Access : You can view the full table of contents and index on the Cambridge University Press Python Wrapper
Find a used copy of Numerical Recipes in C (the hardcover is cheap now). Read the chapter introductions. They explain why the algorithm works. Then, walk away from the C code and implement the logic using NumPy broadcasting. numerical recipes python pdf
However, there is a significant catch:
First published in 1986, Numerical Recipes became the "cookbook" for computational work. It didn't just give you formulas; it provided tested, ready-to-type code for: (3rd Edition) by Press et al
If you must implement a specific algorithm from the book (e.g., for educational purposes): They explain why the algorithm works