Web Application Development with R using Shiny

Chris Beeley

• Publisher: Packt Publishing
• Year: 2013
• eBook ISBN: 9781783284474
• Topic: Informatique
• Subtopic: Développement d'applications

In Detail

R is a highly flexible and powerful tool for analyzing and visualizing data. Shiny is the perfect companion to R, making it quick and simple to share analysis and graphics from R that users can interact with and query over the Web. Let Shiny do the hard work and spend your time generating content and styling, not writing code to handle user inputs.

Web Application Development with R Using Shiny is an accessible introduction to sharing interactive content from R using Shiny. You will learn by doing, with each chapter including code and examples to use and adapt for your own applications. By the end of this book, you will be able to build useful and engaging web applications with only a few lines of code no JavaScript required.

Web Application Development with R Using Shiny will show you how to begin analyzing, visualizing, and sharing your data using practical examples.

This book will teach you how to rapidly prototype and build interactive data summaries using Shiny's built-in widgets and functions. You will learn how to integrate Shiny applications with your existing HTML and CSS, how to greatly extend the power and usability of your applications using JavaScript, and how to quickly deploy them over the Web.

The book uses practical examples to show you how to get the best out of R and Shiny, helping you to produce and share cutting-edge analytics with minimal effort.

Approach

This book follows a standard tutorial-based approach which will teach you how to make a web app using R and Shiny quickly and easily.

Who this book is for

This book is for anybody who wants to produce interactive data summaries over the Web, whether you want to share them with a few colleagues or the whole world. You need no previous experience with R, Shiny, HTML, or CSS to begin using this book, although you will need at least a little previous experience with programming in a different language.

Web Application Development with R Using Shiny

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Table of Contents

Web Application Development with R Using Shiny

Credits

About the Author

Acknowledgement

About the Reviewers

www.PacktPub.com

Support files, eBooks, discount offers and more

Why Subscribe?

Free Access for Packt account holders

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Errata

Piracy

Questions

1. Installing R and Shiny and Getting Started!

Installing R

The R console

Code editors and IDEs

Simple and well-featured

Complex and extensible

Learning R

Getting help

Loading data

Dataframes, lists, arrays, and matrices

Variable types

Functions

Objects

Base graphics and ggplot2

Bar chart

Line chart

Installing Shiny and running the examples

Summary

2. Building Your First Application

Program structure

ui.R of minimal example

server.R of minimal example

Optional exercise

Widget types

Google Analytics application

The UI

Data processing

Reactive objects

Outputs

A note on the application code

Optional exercise

Summary

3. Building Your Own Web Pages with Shiny

Running the applications and code

Shiny and HTML

Custom HTML links in Shiny

ui.R

server.R

server.R – data preparation

server.R – server definition

Minimal HTML interface

index.html

server.R

JavaScript and Shiny

ui.R

server.R

jQuery

index.html – body

server.R

jQuery

Exercise

Summary

4. Taking Control of Reactivity, Inputs, and Outputs

Showing and hiding elements of the UI

Giving names to tabPanel elements

Reactive user interfaces

Reactive user interface example – server.R

Reactive user interface example – ui.R

Advanced reactivity

Using reactive objects and functions efficiently

Controlling the whole interface with the submitButton() function

Controlling specific inputs with the isolate() function

Running reactive functions over time

More advanced topics in Shiny

Finely controlling inputs and outputs

Reading client information and GET requests in Shiny

Custom interfaces from GET strings

Animation

Advanced graphics options

Downloading graphics

Downloading and uploading data

Summary

5. Running and Sharing Your Creations

Sharing with the R community

Sharing over GitHub

Introduction to Git

Sharing applications using Git

Sharing using .zip and .tar

Sharing with the world

Glimmer

Shiny Server

Browser compatibility

Summary

Index

Web Application Development with R Using Shiny

Copyright © 2013 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: October 2013

Production Reference: 1151013

Published by Packt Publishing Ltd.

Livery Place

35 Livery Street

Birmingham B3 2PB, UK.

ISBN 978-1-78328-447-4

www.packtpub.com

Cover Image by Suresh Mogre (<[email protected]>)

Credits

Author

Chris Beeley

Reviewers

Neependra Khare

Ram Narasimhan

Hernán G. Resnizky

Acquisition Editor

Kevin Colaco

Commissioning Editor

Shaon Basu

Technical Editors

Aparna Chand

Dennis John

Project Coordinator

Suraj Bist

Proofreader

Joanna McMahon

Indexers

Monica Ajmera Mehta

Tejal R. Soni

Production Coordinator

Prachali Bhiwandkar

Cover Work

Prachali Bhiwandkar

About the Author

Chris Beeley is an Applied Researcher working in healthcare in the UK. He completed his PhD in Psychology at the University of Nottingham in 2009 and now works with Nottinghamshire Healthcare NHS Trust providing statistical analysis and other types of evaluation and reporting using routine data generated within the Trust. Chris has a special interest in the use of regression methods in applied healthcare settings, particularly forensic psychiatric settings, as well as in the collection, analysis, and reporting of patient feedback data.

Chris has been a keen user of R and a passionate advocate of open-source tools within research and healthcare settings since completing his PhD. He has made extensive use of R (and Shiny) to automate analysis and reporting for new patient feedback websites. This was funded by a grant from the NHS Institute for Innovation and made in collaboration with staff, service users, and carers within the Trust, particularly individuals from the Involvement Center.

Acknowledgement

I would like to thank all the staff, service users, and carers at the Involvement Center in Nottinghamshire Healthcare NHS Trust, not only for welcoming me and believing in me but also for making my work meaningful. Helping to better understand and communicate with our service users and carers is the reason why I get out of bed in the morning and work long hours on the website. The book was made much easier with the thought that it might help transform healthcare for everyone's benefit.

I'd like to give a massive thank you to the whole R world, the R core team, the people at RStudio, Joe Cheng, Winston Chang, Hadley Wickham (what was life like before ggplot2?) and all the people I've had so much help from over the years, on mailing lists, forums, blog posts, and wherever else I've found you. Everyone who believes in free and open source believes that by cooperating and sharing we can build a better world, and this is a profound message not just in the world of software, but globally everywhere. I could never hope to give back as much to this community as I've taken already, but I promise to try.

I would also like to thank my wife and son who helped me remember that there's more to life than coding and work, and are, in general, the complete opposite of writing a book about an R package.

About the Reviewers

Neependra Khare has around 9 years of experience in the IT industry. He has worked as a SysAdmin, support engineer, and a filesystem developer. Currently he is working with Red Hat as Principal Software Engineer.

As a data enthusiast, he uses R and Shiny to do the analysis and publish visualizations. More can be found out about him on his website at www.neependra.net.

Ram Narasimhan works in the Data Science group at GE Global Research. He has worked in applied data analysis for over 15 years, including working as a data consultant in multiple verticals (transportation, manufacturing, and sup...

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