Book Image

D3.js 4.x Data Visualization - Third Edition

By : Aendrew Rininsland, Teller
Book Image

D3.js 4.x Data Visualization - Third Edition

By: Aendrew Rininsland, Teller

Overview of this book

Want to get started with impressive interactive visualizations and implement them in your daily tasks? This book offers the perfect solution-D3.js. It has emerged as the most popular tool for data visualization. This book will teach you how to implement the features of the latest version of D3 while writing JavaScript using the newest tools and technique You will start by setting up the D3 environment and making your first basic bar chart. You will then build stunning SVG and Canvas-based data visualizations while writing testable, extensible code,as accurate and informative as it is visually stimulating. Step-by-step examples walk you through creating, integrating, and debugging different types of visualization and will have you building basic visualizations (such as bar, line, and scatter graphs) in no time. By the end of this book, you will have mastered the techniques necessary to successfully visualize data and will be ready to use D3 to transform any data into an engaging and sophisticated visualization.
Table of Contents (11 chapters)
3
Shape Primitives of D3

Scales

We've already used scales many times -- we had a chant, if you remember; what was that again?

SURPRISE POP QUIZ:

INPUT!: [ ] DOMAIN! [ ] NOT DOMAIN!
OUTPUT!: [ ] RANGE! [ ] NOT RANGE!

If you got INPUT! = DOMAIN! and OUTPUT! = RANGE!, you are totally correct!

The reason we use scales is to avoid math. This makes our code shorter, easier to understand, and more robust, as mistakes in high school mathematics are some of the hardest bugs to track down.

To reiterate a point I've hopefully been hammering home since Chapter 1, Getting Started with D3, ES2017, and Node.js, a function's domains are those values that are defined (the input), and the range are those values it returns.

The following figure is borrowed from Wikipedia:

Here, X is the domain, Y is the range, and the arrows are the functions. We need a bunch of code to implement this manually:

   let shape_color...