Book Image

Java Data Science Cookbook

By : Rushdi Shams
Book Image

Java Data Science Cookbook

By: Rushdi Shams

Overview of this book

If you are looking to build data science models that are good for production, Java has come to the rescue. With the aid of strong libraries such as MLlib, Weka, DL4j, and more, you can efficiently perform all the data science tasks you need to. This unique book provides modern recipes to solve your common and not-so-common data science-related problems. We start with recipes to help you obtain, clean, index, and search data. Then you will learn a variety of techniques to analyze, learn from, and retrieve information from data. You will also understand how to handle big data, learn deeply from data, and visualize data. Finally, you will work through unique recipes that solve your problems while taking data science to production, writing distributed data science applications, and much more - things that will come in handy at work.
Table of Contents (16 chapters)
Java Data Science Cookbook
About the Author
About the Reviewer
Customer Feedback

Counting word frequency in a string

This recipe is quite different than the other recipes in this chapter as it deals with strings and counting word frequencies in a string. We will use both Apache Commons Math and Java 8 for this task. This recipe will use the external library while the next recipe will achieve the same with Java 8.

How to do it...

  1. Create a method that takes a String array. The array contains all the words in a string:

            public void getFreqStats(String[] words){ 
  2. Create a Frequency class object:

            Frequency freq = new Frequency(); 
  3. Add all the words to the Frequency object:

            for( int i = 0; i < words.length; i++) { 
  4. For each word, count the frequency using the Frequency class's getCount() method. Finally, after processing the frequencies, close the method:

        for( int i = 0; i < words.length; i++) { 
           System.out.println(words[i] + "=" +