Book Image

TensorFlow Reinforcement Learning Quick Start Guide

By : Kaushik Balakrishnan
Book Image

TensorFlow Reinforcement Learning Quick Start Guide

By: Kaushik Balakrishnan

Overview of this book

Advances in reinforcement learning algorithms have made it possible to use them for optimal control in several different industrial applications. With this book, you will apply Reinforcement Learning to a range of problems, from computer games to autonomous driving. The book starts by introducing you to essential Reinforcement Learning concepts such as agents, environments, rewards, and advantage functions. You will also master the distinctions between on-policy and off-policy algorithms, as well as model-free and model-based algorithms. You will also learn about several Reinforcement Learning algorithms, such as SARSA, Deep Q-Networks (DQN), Deep Deterministic Policy Gradients (DDPG), Asynchronous Advantage Actor-Critic (A3C), Trust Region Policy Optimization (TRPO), and Proximal Policy Optimization (PPO). The book will also show you how to code these algorithms in TensorFlow and Python and apply them to solve computer games from OpenAI Gym. Finally, you will also learn how to train a car to drive autonomously in the Torcs racing car simulator. By the end of the book, you will be able to design, build, train, and evaluate feed-forward neural networks and convolutional neural networks. You will also have mastered coding state-of-the-art algorithms and also training agents for various control problems.
Table of Contents (11 chapters)

The A3C algorithm applied to CartPole

Here, we will code A3C in TensorFlow and apply it so that we can train an agent to learn the CartPole problem. The following code files will be required to code:

  • cartpole.py: This will start the training or testing process
  • a3c.py: This is where the A3C algorithm is coded
  • utils.py: This includes utility functions

Coding cartpole.py

We will now code cartpole.py. Follow these steps to get started:

  1. First, we import the packages:
import numpy as np
import matplotlib.pyplot as plt
import tensorflow as tf
import gym
import os
import threading
import multiprocessing

from random import choice
from time import sleep
from time import time

from a3c import *
from utils import *
  1. Next, we set the parameters...