The sixth lesson of the Udacity Self-Driving Car Engineer Nanodegree Program is “Introduction to TensorFlow.”
TensorFlow is Google’s library for deep learning, and one of the most popular tools for building and training deep neural networks. In the previous lesson, MiniFlow, students build their own miniature versions of a deep learning library. But for real deep learning work, an industry-standard library like TensorFlow is essential.
Students learn the differences between regression and classification problems. Then they to build a logistic classifier in TensorFlow. Finally, students use fundamental techniques like activation functions, one-hot encoding, and cross-entropy loss to train feedforward networks.
Most of these topics are already familiar to students from the previous “Introduction to Neural Networks” and “MiniFlow” lessons, but implementing them in TensorFlow is a whole new animal. This lesson provides lots of quizzes and solutions demonstrating how to do that.
Towards the end of the lesson, students walk through a quick tutorial on using GPU-enabled AWS EC2 instances to train deep neural networks. Thank you to our friends at AWS Educate for providing free credits to Udacity students to use for training neural networks!
Deep learning has been around for a long time, but it has only really taken off in the last five years because of the ability to use GPUs to dramatically accelerate the training of neural networks. Students who have their own high-performance GPUs are able to experience this acceleration locally. But many students do not own their own GPUs, and AWS EC2 instances are a cloud tool for achieving the same results from anywhere.
The lesson closes with a lab in which students use TensorFlow to perform the classic deep learning exercise of classifying characters: ‘A’, ‘B’, ‘C’ and so on.