Book Image

Python: Advanced Guide to Artificial Intelligence

By : Giuseppe Bonaccorso, Rajalingappaa Shanmugamani
Book Image

Python: Advanced Guide to Artificial Intelligence

By: Giuseppe Bonaccorso, Rajalingappaa Shanmugamani

Overview of this book

This Learning Path is your complete guide to quickly getting to grips with popular machine learning algorithms. You'll be introduced to the most widely used algorithms in supervised, unsupervised, and semi-supervised machine learning, and learn how to use them in the best possible manner. Ranging from Bayesian models to the MCMC algorithm to Hidden Markov models, this Learning Path will teach you how to extract features from your dataset and perform dimensionality reduction by making use of Python-based libraries. You'll bring the use of TensorFlow and Keras to build deep learning models, using concepts such as transfer learning, generative adversarial networks, and deep reinforcement learning. Next, you'll learn the advanced features of TensorFlow1.x, such as distributed TensorFlow with TF clusters, deploy production models with TensorFlow Serving. You'll implement different techniques related to object classification, object detection, image segmentation, and more. By the end of this Learning Path, you'll have obtained in-depth knowledge of TensorFlow, making you the go-to person for solving artificial intelligence problems This Learning Path includes content from the following Packt products: • Mastering Machine Learning Algorithms by Giuseppe Bonaccorso • Mastering TensorFlow 1.x by Armando Fandango • Deep Learning for Computer Vision by Rajalingappaa Shanmugamani
Table of Contents (31 chapters)
Title Page
About Packt
Contributors
Preface
19
Tensor Processing Units
Index

Applying simple policies to a cartpole game


So far, we have randomly picked an action and applied it. Now let us apply some logic to picking the action instead of random chance. The third observation refers to the angle. If the angle is greater than zero, that means the pole is tilting right, thus we move the cart to the right (1). Otherwise, we move the cart to the left (0). Let us look at an example:

  1. We define two policy functions as follows:
def policy_logic(env,obs):
return 1 if obs[2] > 0 else 0
def policy_random(env,obs):
return env.action_space.sample()

 

 

 

 

  1. Next, we define an experiment function that will run for a specific number of episodes; each episode runs until the game is lost, namely when done is True. We use rewards_max to indicate when to break out of the loop as we do not wish to run the experiment forever:
def experiment(policy, n_episodes, rewards_max):
rewards=np.empty(shape=(n_episodes))
    env = gym.make('CartPole-v0')

for i in range(n_episodes):
obs = env.reset(...