A LaTeX/TikZ/PGF package for drawing directed graphs, such as neural network schematics.
I started a project to create an open-source mid-level Machine Learning textbook, based on some notes from a Caltech course and a Coursera course. The contributions from the community were of poor quality and laden with mistakes, so I eventually terminated the project (having rejected all public submissions).
I will work on the book as an occasional project for my own benefit, but it is not a priority any more. I have stopped working on the book.
To rapidly produce neural network illustrations in the book, I created a LaTeX package to wrap all the TikZ/PGF clutter. The result is a set of LaTeX macros that allow high quality neural-network graphs to be drawn rapidly, and I have since made the package publicly available via my github repository.