Book Image

Learn D3.js

By : Helder da Rocha
2 (1)
Book Image

Learn D3.js

2 (1)
By: Helder da Rocha

Overview of this book

This book is a practical hands-on introduction to D3 (Data-driven Documents): the most popular open-source JavaScript library for creating interactive web-based data visualizations. Based entirely on open web standards, D3 provides an integrated collection of tools for efficiently binding data to graphical elements. If you have basic knowledge of HTML, CSS and JavaScript you can use D3.js to create beautiful interactive web-based data visualizations. D3 is not a charting library. It doesn’t contain any pre-defined chart types, but can be used to create whatever visual representations of data you can imagine. The goal of this book is to introduce D3 and provide a learning path so that you obtain a solid understanding of its fundamental concepts, learn to use most of its modules and functions, and gain enough experience to create your own D3 visualizations. You will learn how to create bar, line, pie and scatter charts, trees, dendograms, treemaps, circle packs, chord/ribbon diagrams, sankey diagrams, animated network diagrams, and maps using different geographical projections. Fundamental concepts are explained in each chapter and then applied to a larger example in step-by-step tutorials, complete with full code, from hundreds of examples you can download and run. This book covers D3 version 5 and is based on ES2015 JavaScript.
Table of Contents (13 chapters)

Enclosure diagrams

Enclosure diagrams reveal the topology of a hierarchy through containment. Circle packing places leaf nodes in circles, which represent subtrees. Their cumulative size determines the size of the enclosing circle, but the use of space in this type of chart is not very efficient. Treemaps use rectangles instead of circles and are more space-efficient. They also allow areas to be compared with more precision, but circle packing is usually better at emphasizing topology.

The following diagrams show the same data rendered with circle packing and treemap layouts. The full code and the data files used to generate these charts are available from the GitHub repository for this chapter:

Country and continent populations (2016) visualized with circle packing. Code: Examples/pack-2-world-by-population.html.

A treemap visualization is shown below. It uses exactly the same...