Machine Learning Libraries for Programmers

This is a list of machine learning libraries that I originally posted on my blog. It is organized by programming language and I tried to list the libraries in order of popularity and available resources.

Python ( Python 2.7 / Python 3.X)

Tensorflow Google's super popular library that reached version 1.0 this year (2017).

PyTorch A great Python library inspired by Torch. It is used a lot in research and is a serious contender to Tensorflow

Keras A higher level abstraction library built on top of Tensorflow

scikit-learn Another high level library geared towards learning.

Jupyter Notebook style workflow with IPython

Java

Deeplearning4j Java deep learning library

Apache OpenNLP Natural Language Processing

C++

Tensorflow C++ API API for C++

MLPACK Scalable ML library

R 

I'm not familiar with R myself, but here's some stuff I found:
Introducing: Machine Learning in R
Top 20 R machine learning and data packages