Getting Started with D3

Preface

The D3 JavaScript library allows us to make beautiful, interactive, browser-based data visualizations. By exposing the underlying elements of a web page in the context of a data set, D3 gives you complete control over your visualization. This fantastic power, though, comes with a short, sharp learning curve—a curve that this book aims to overcome.

By working through a collection of data sets, we will build up a series of visualizations, exposing new D3 concepts along the way. The data for this book has been gathered and made publicly available by the New York Metropolitan Transit Authority (MTA) and details various aspects of New York’s transit system, comprising of historical tables, live data streams, and geographical information. By the end of the book, we will have visited some of the core aspects of D3, and will be properly equipped to build basic, interactive data visualizations on the Web.

Who This Book Is For

This is a little book aimed at the data scientist: someone who has data to visualize and who wants to use the power of the modern web browser to give his visualizations additional impact. This might be an academic who wants to escape the confines of the printed article, a statistician who needs to share their impressive results with the rest of her company, or the designer who wants to get his info-viz out far and wide on the Internet.

It’s assumed, therefore, that the reader is happy with coding and manipulating data. We will not cover any statistics or modelling, we will not stray outside the JavaScript or SVG we need for the visualizations, and we won’t discuss aesthetics past what we consider basic good taste. These are important topics and we point to Machine Learning for Hackers by Drew Conway and John Myles White, JavaScript: The Good Parts by Douglas Crockford, SVG Essentials by J. David Eisenberg, and Visualizing Data by Ben Fry for these important introductions.

Conventions Used in This Book

The following typographical conventions are used in this book:

Italic

Indicates new terms, URLs, email addresses, filenames, and file extensions.

Constant width

Used for program listings, as well as within paragraphs to refer to program elements such as variable or function names, databases, data types, environment variables, statements, and keywords.

Constant width bold

Shows commands or other text that should be typed literally by the user.

Constant width italic

Shows text that should be replaced with user-supplied values or by values determined by context.

Tip

This icon signifies a tip, suggestion, or general note.

Caution

This icon indicates a warning or caution.

Using Code Examples

This book is here to help you get your job done. In general, you may use the code in this book in your programs and documentation. You do not need to contact us for permission unless you’re reproducing a significant portion of the code. For example, writing a program that uses several chunks of code from this book does not require permission. Selling or distributing a CD-ROM of examples from O’Reilly books does require permission. Answering a question by citing this book and quoting example code does not require permission. Incorporating a significant amount of example code from this book into your product’s documentation does require permission.

We appreciate, but do not require, attribution. An attribution usually includes the title, author, publisher, and ISBN. For example: “Getting Started with D3 by Mike Dewar (O’Reilly). Copyright 2012 Mike Dewar, 978-1-449-32879-5.”

If you feel your use of code examples falls outside fair use or the permission given above, feel free to contact us at [e-mail].

Safari® Books Online

Note

Safari Books Online (www.safaribooksonline.com) is an on-demand digital library that delivers expert content in both book and video form from the world’s leading authors in technology and business.

Technology professionals, software developers, web designers, and business and creative professionals use Safari Books Online as their primary resource for research, problem solving, learning, and certification training.

Safari Books Online offers a range of product mixes and pricing programs for organizations, government agencies, and individuals. Subscribers have access to thousands of books, training videos, and prepublication manuscripts in one fully searchable database from publishers like O’Reilly Media, Prentice Hall Professional, Addison-Wesley Professional, Microsoft Press, Sams, Que, Peachpit Press, Focal Press, Cisco Press, John Wiley & Sons, Syngress, Morgan Kaufmann, IBM Redbooks, Packt, Adobe Press, FT Press, Apress, Manning, New Riders, McGraw-Hill, Jones & Bartlett, Course Technology, and dozens more. For more information about Safari Books Online, please visit us online.

How to Contact Us

Please address comments and questions concerning this book to the publisher:

O’Reilly Media, Inc.

1005 Gravenstein Highway North

Sebastopol, CA 95472

800-998-9938 (in the United States or Canada)

707-829-0515 (international or local)

707-829-0104 (fax)

We have a web page for this book, where we list errata, examples, and any additional information. You can access this page at:

http://oreil.ly/get_started_D3

To comment or ask technical questions about this book, send email to:

[e-mail]

For more information about our books, courses, conferences, and news, see our website at http://www.oreilly.com.

Find us on Facebook: http://facebook.com/oreilly

Follow us on Twitter: http://twitter.com/oreillymedia

Watch us on YouTube: http://www.youtube.com/oreillymedia

Acknowledgements

I’d like to thank Mike Bostock for putting together such a fine library, and for his help and comments. My good friends and colleagues Brian Eoff, John Myles White, Drew Conway, Max Shron, and Gabriel Gaster have all helped tremendously with technical comments (and the occasional British to American English conversion). My editor and conscience Meghan Blanchette has been remarkably effective, somehow coaxing this little book out of me without yelling. Most of all, I’d like to thank my fiancee Monica Vakil for her love, patience, and support.