What was left out
We did not cover every machine learning package available for Python. Given the limited space, we chose to focus on Scikit-learn. However, there are other options, and we list a few of them here:
Modular toolkit for Data Processing (MDP ) at http://mdp-toolkit.sourceforge.net
Pybrain at http://pybrain.org
Machine Learning Toolkit (MILK) at http://luispedro.org/software/milk
This package was developed by one of the authors of this book, and covers some algorithms and techniques that are not included in Scikit-learn.
A more general resource is at http://mloss.org, which is a repository of open source machine learning software. As is usually the case with repositories such as this one, the quality varies between excellent, well-maintained software and projects that were one-offs and then abandoned. It may be worth checking out if your problem is very specific and none of the more general packages address it.
