A fast, safe and easy to use reinforcement learning framework in Rust.
Switch branches/tags
Clone or download
Latest commit 11fcf65 Nov 22, 2018


RSRL (api)

Crates.io Build Status Coverage Status

Reinforcement learning should be fast, safe and easy to use.


rsrl provides generic constructs for running reinforcement learning (RL) experiments by providing a simple, extensible framework and efficient implementations of existing methods for rapid prototyping.


rsrl = "0.6"


The code below shows how one could use rsrl to evaluate a GreedyGQ agent using a Fourier basis function approximator to solve the canonical mountain car problem.

See examples/ for more...

extern crate rsrl;
extern crate slog;

use rsrl::{
    core::{run, Evaluation, Parameter, SerialExperiment, make_shared, Trace},
    domains::{Domain, MountainCar},
    fa::{projectors::fixed::Fourier, LFA},

fn main() {
    let logger = logging::root(logging::stdout());

    let domain = MountainCar::default();
    let mut agent = {
        let n_actions = domain.action_space().card().into();

        // Build the linear value functions using a fourier basis projection.
        let bases = Fourier::from_space(3, domain.state_space());
        let v_func = make_shared(LFA::simple(bases.clone()));
        let q_func = make_shared(LFA::multi(bases, n_actions));

        // Build a stochastic behaviour policy with exponential epsilon.
        let eps = Parameter::exponential(0.99, 0.05, 0.99);
        let policy = make_shared(EpsilonGreedy::new(q_func.clone(), eps));

        GreedyGQ::new(q_func, v_func, policy, 1e-1, 1e-3, 0.99)

    let domain_builder = Box::new(MountainCar::default);

    // Training phase:
    let _training_result = {
        // Start a serial learning experiment up to 1000 steps per episode.
        let e = SerialExperiment::new(&mut agent, domain_builder.clone(), 1000);

        // Realise 1000 episodes of the experiment generator.
        run(e, 1000, Some(logger.clone()))

    // Testing phase:
    let testing_result = Evaluation::new(&mut agent, domain_builder).next().unwrap();

    info!(logger, "solution"; testing_result);


Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate and adhere to the angularjs commit message conventions (see here).