Book Image

The Reinforcement Learning Workshop

By : Alessandro Palmas, Emanuele Ghelfi, Dr. Alexandra Galina Petre, Mayur Kulkarni, Anand N.S., Quan Nguyen, Aritra Sen, Anthony So, Saikat Basak
Book Image

The Reinforcement Learning Workshop

By: Alessandro Palmas, Emanuele Ghelfi, Dr. Alexandra Galina Petre, Mayur Kulkarni, Anand N.S., Quan Nguyen, Aritra Sen, Anthony So, Saikat Basak

Overview of this book

Various intelligent applications such as video games, inventory management software, warehouse robots, and translation tools use reinforcement learning (RL) to make decisions and perform actions that maximize the probability of the desired outcome. This book will help you to get to grips with the techniques and the algorithms for implementing RL in your machine learning models. Starting with an introduction to RL, youÔÇÖll be guided through different RL environments and frameworks. YouÔÇÖll learn how to implement your own custom environments and use OpenAI baselines to run RL algorithms. Once youÔÇÖve explored classic RL techniques such as Dynamic Programming, Monte Carlo, and TD Learning, youÔÇÖll understand when to apply the different deep learning methods in RL and advance to deep Q-learning. The book will even help you understand the different stages of machine-based problem-solving by using DARQN on a popular video game Breakout. Finally, youÔÇÖll find out when to use a policy-based method to tackle an RL problem. By the end of The Reinforcement Learning Workshop, youÔÇÖll be equipped with the knowledge and skills needed to solve challenging problems using reinforcement learning.
Table of Contents (14 chapters)
Preface
Free Chapter
2
2. Markov Decision Processes and Bellman Equations

Deep Deterministic Policy Gradients

In this section, we will apply the DDPG technique to understand the continuous action space. Moreover, we will learn how to code a moon lander simulation to understand DDPGs.

Note

We suggest that you type all the code given in this section into your Jupyter notebook as we will be using it later, in Exercise 11.02, Creating a Learning Agent.

We are going to use the OpenAI Gym Lunar Lander environment for continuous action spaces here. Let's start by importing the essentials:

import os
import gym
import torch as T
import numpy as np

Now, we will learn how to define some classes, such as the OUActionNoise class, the ReplayBuffer class, the ActorNetwork class, and the CriticNetwork class, which will help us to implement the DDGP technique. At the end of this section, you'll have the complete code base that applies the DDPG within our OpenAI Gym game environment.

Ornstein-Uhlenbeck Noise

First, we will define...