Scala

Scala is a modern programming language that is emerging as an alternative to traditional programming languages such as Java and C++. Scala is a JVM-based language that not only offers a concise syntax without the traditional boilerplate code, but also incorporates both object-oriented and functional programming into an extremely crisp and extraordinarily powerful type-safe language.

Scala takes a flexible and expressive approach, which makes it perfect for interacting with Spark's MLlib. The fact that Spark itself is written in Scala provides a strong evidence that the Scala language is a full-service programming language that can be used to create sophisticated system code with heavy performance needs.

Scala builds on Java's tradition by addressing some of its shortcomings, while avoiding an all-or-nothing approach. Scala code compiles into Java bytecode, which in turn makes it possible to coexist with rich Java libraries interchangeably. The ability to use Java libraries with Scala and vice versa provides continuity and a rich environment for software engineers to build modern and complex machine learning systems without being fully disconnected from the Java tradition and code base.

Scala fully supports a feature-rich functional programming paradigm with standard support for lambda, currying, type interface, immutability, lazy evaluation, and a pattern-matching paradigm reminiscent of Perl without the cryptic syntax. Scala is an excellent match for machine learning programming due to its support for algebra-friendly data types, anonymous functions, covariance, contra-variance, and higher-order functions.

Here's a hello world program in Scala:

object HelloWorld extends App { 
   println("Hello World!") 
 } 

Compiling and running HelloWorld in Scala looks like this:

The Apache Spark Machine Learning Cookbook takes a practical approach by offering a multi-disciplinary view with the developer in mind. This book focuses on the interactions and cohesiveness of machine learning, Apache Spark, and Scala. We also take an extra step and teach you how to set up and run a comprehensive development environment familiar to a developer and provide code snippets that you have to run in an interactive shell without the modern facilities that an IDE provides: