### Description

The rl library provides C++ classes and templates for the robust and efficient design of reinforcement learning applications. Templates are used in order to fit the mathematical formalism of the reinforcment learning theory.

### Cite our work...

You can use the rl library freely for your research, for software design as well as education. Please cite the library as follows :

H. FREZZA-BUET, M. GEIST, *"A C++ Template-Based Reinforcement Learning Library : Fitting the Code to the Mathematics"*. In Journal of Machine Learning Research, 14:625 - 628, 2013.

### JMLR Publication

The library has been published in JMLR. The published version is rl-2.04.00, but **this is not the latest release**. For the latest release (recommended), read next section. We still provide the sources and the documentation related to the publication.

### Download and installation

The rl source code, since version 2.04.00, only consists of a set of headers. It is thus quite easy to install manually. Nevertheless, we propose some packaging support.

You can download the latest rl-*.tar.gz library, and then install form sources (see here). You can also use yum if you are using Fedora (see here).

### Documentation

You can find rl documentation here. It is a Doxygen documentation, where examples are numbered. Read them in the suggested order, this will provide you with an up-to-date user manual.

**rl-example-000-002-agents**

This example implements a 50-armed bandit. An agent chooses one of the arms, according to some Q-function associated to each arm. The example plots the histograms of the agent choices (20000 choices are made).

This is the Q-function :

This is the histogram for the random agent :

This is the histogram for the greedy agent :

This is the histogram for the epsilon-greedy agent :

This is the histograms for the Soft-Max agent when the temperature varies :

**rl-example-001-*-cliff-walking-***

The cliff-walking problem, solved with sarsa and Q-learning.

**rl-example-003-003-mountain-car-ktdsarsa**

The command

rl-example-003-003-mountain-car-ktdsarsa learnandmovie 300

generates the Q-function movie. Try with 100 epsides instead of 300, it works.

The command

rl-example-003-003-mountain-car-ktdsarsa test bottom

generates an episode like this