Book Image

Fast Data Processing with Spark 2 - Third Edition

By : Holden Karau
Book Image

Fast Data Processing with Spark 2 - Third Edition

By: Holden Karau

Overview of this book

When people want a way to process big data at speed, Spark is invariably the solution. With its ease of development (in comparison to the relative complexity of Hadoop), it’s unsurprising that it’s becoming popular with data analysts and engineers everywhere. Beginning with the fundamentals, we’ll show you how to get set up with Spark with minimum fuss. You’ll then get to grips with some simple APIs before investigating machine learning and graph processing – throughout we’ll make sure you know exactly how to apply your knowledge. You will also learn how to use the Spark shell, how to load data before finding out how to build and run your own Spark applications. Discover how to manipulate your RDD and get stuck into a range of DataFrame APIs. As if that’s not enough, you’ll also learn some useful Machine Learning algorithms with the help of Spark MLlib and integrating Spark with R. We’ll also make sure you’re confident and prepared for graph processing, as you learn more about the GraphX API.
Table of Contents (18 chapters)
Fast Data Processing with Spark 2 Third Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface

ML pipelines


ML pipelines were developed to address the fact that machine learning is not just a bunch of algorithms, such as classification and regression, but a pipeline of actions performed over a Dataset. Let's take a quick look at the tasks involved in a typical machine learning process. The following figure shows the top-level activities:

The first step is to get some data for the data science work. If you are using internal data, the data should be made anonymous and all PII information purged.

Once we have the data, we'll transform it: for example, we can convert a comma-separated CSV format into a DataFrame consisting of strings and numbers.

Then we extract the features that can be used to train our machine learning models. The feature extraction can be as simple as separating lines into words or normalizing words, such as deleting special characters and converting words to lowercase. This might also involve turning columns into categories, for example, Yes/No to 1/0 or Survived...