Book Image

Learning D3.js 5 Mapping - Second Edition

By : Thomas Newton, Oscar Villarreal, Lars Verspohl
Book Image

Learning D3.js 5 Mapping - Second Edition

By: Thomas Newton, Oscar Villarreal, Lars Verspohl

Overview of this book

D3.js is a visualization library used for the creation and control of dynamic and interactive graphical forms. It is a library used to manipulate HTML and SVG documents as well as the Canvas element based on data. Using D3.js, developers can create interactive maps for the web, that look and feel beautiful. This book will show you how build and design maps with D3.js and gives you great insight into projections, colors, and the most appropriate types of map. The book begins by helping you set up all the tools necessary to build visualizations and maps. Then it covers obtaining geographic data, modifying it to your specific needs, visualizing it with augmented data using D3.js. It will further show you how to draw and map with the Canvas API and how to publish your visualization. By the end of this book, you'll be creating maps like the election maps and the kind of infographics you'll find on sites like the New York Times.
Table of Contents (13 chapters)
6
Finding and Working with Geographic Data

Finding and Working with Geographic Data

We have spent a significant amount of time creating and interacting with maps in our previous chapters. In all our examples, the geographic data was included. In this chapter, we will explain how to find geographic data about any country in the world.

There are typically two sets of data that we will need to create a map in D3:

  • A dataset that represents the geographic shape of our map (geodata)
  • Some meaningful data that we want to visualize on the map (for example, population density by US countries, or unemployment rate by countries in the world)

This chapter is focused on understanding, manipulating, and optimizing geodata for map visualizations. We will accomplish these goals by:

  • Explaining three important formats that contain geospatial vector data
  • Finding, downloading, and working with large amounts of map data
  • Using techniques...