Book Image

Machine Learning with R Cookbook

By : Yu-Wei, Chiu (David Chiu)
Book Image

Machine Learning with R Cookbook

By: Yu-Wei, Chiu (David Chiu)

Overview of this book

<p>The R language is a powerful open source functional programming language. At its core, R is a statistical programming language that provides impressive tools to analyze data and create high-level graphics.</p> <p>This book covers the basics of R by setting up a user-friendly programming environment and performing data ETL in R. Data exploration examples are provided that demonstrate how powerful data visualization and machine learning is in discovering hidden relationships. You will then dive into important machine learning topics, including data classification, regression, clustering, association rule mining, and dimension reduction.</p>
Table of Contents (21 chapters)
Machine Learning with R Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Resources for R and Machine Learning
Dataset – Survival of Passengers on the Titanic
Index

Manipulating data with plyrmr


While writing a MapReduce program with rmr2 is much easier than writing a native Java version, it is still hard for nondevelopers to write a MapReduce program. Therefore, you can use plyrmr, a high-level abstraction of the MapReduce program, so that you can use plyr-like operations to manipulate big data. In this recipe, we will introduce some operations you can use to manipulate data.

Getting ready

In this recipe, you should have completed the previous recipes by installing plyrmr and rmr2 in R.

How to do it...

Perform the following steps to manipulate data with plyrmr:

  1. First, you need to load both plyrmr and rmr2 into R:

    > library(rmr2)
    > library(plyrmr)
    
  2. You can then set the execution mode to the local mode:

    > plyrmr.options(backend="local")
    
  3. Next, load the Titanic dataset into R:

    > data(Titanic)
    > titanic = data.frame(Titanic)
    
  4. Begin the operation by filtering the data:

    > where(
    +    Titanic, 
    + Freq >=100)
    
  5. You can also use a pipe operator to...