Book Image

Mastering Scala Machine Learning

By : Alex Kozlov
Book Image

Mastering Scala Machine Learning

By: Alex Kozlov

Overview of this book

Since the advent of object-oriented programming, new technologies related to Big Data are constantly popping up on the market. One such technology is Scala, which is considered to be a successor to Java in the area of Big Data by many, like Java was to C/C++ in the area of distributed programing. This book aims to take your knowledge to next level and help you impart that knowledge to build advanced applications such as social media mining, intelligent news portals, and more. After a quick refresher on functional programming concepts using REPL, you will see some practical examples of setting up the development environment and tinkering with data. We will then explore working with Spark and MLlib using k-means and decision trees. Most of the data that we produce today is unstructured and raw, and you will learn to tackle this type of data with advanced topics such as regression, classification, integration, and working with graph algorithms. Finally, you will discover at how to use Scala to perform complex concept analysis, to monitor model performance, and to build a model repository. By the end of this book, you will have gained expertise in performing Scala machine learning and will be able to build complex machine learning projects using Scala.
Table of Contents (17 chapters)
Mastering Scala Machine Learning
Credits
About the Author
Acknowlegement
www.PacktPub.com
Preface
10
Advanced Model Monitoring
Index

GraphX


While graph for Scala may be considered a DSL for graph operations and querying, one should go to GraphX for scalability. GraphX is build on top of a powerful Spark framework. As an example of Spark/GraphX operations, I'll use the CMU Enron e-mail dataset (about 2 GB). The actual semantic analysis of the e-mail content is not going to be important to us until the next chapters. The dataset can be downloaded from the CMU site. It has e-mail from mailboxes of 150 users, primarily Enron managers, and about 517,401 e-mails between them. The e-mails may be considered as an indication of a relation (edge) between two people: Each email is an edge between a source (From:) and a destination (To:) vertices.

Since GraphX requires the data in RDD format, I'll have to do some preprocessing. Luckily, it is extremely easy with Scala—this is why Scala is the perfect language for semi-structured data. Here is the code:

package org.akozlov.chapter07

import scala.io.Source

import scala.util.hashing...