Three short notes on the Python data stack, written in 2018 as the working minimum for someone coming into data work from application development: NumPy for n-dimensional arrays, Pandas for tabular data, and Matplotlib with Seaborn for plotting.

None of this is a course. It is the set of operations I found myself looking up over and over, collected so I would stop looking them up. The APIs have moved since, and Pandas in particular has changed enough that some of the indexing patterns here now raise warnings.