How I Made That: Interactive Heatmap

Add interaction so that you can show different segments of the data and allow comparisons.

The How I Made That series describes the process behind a graphic and includes code and data to work with.

In its simplest form, a heatmap is a grid of cells that you color based on data. An interactive version can help you compare categories, groups, or in this example, time segments.

To compare male and female income in American households, I used a heatmap that looked like this:

A click of the button lets you compare the distribution of income in the household in 1970 against 2015. Try it out here.

In this walk-through, I’ll show you a simplified version of the interactive and describe how you can apply this to your own data.

To access this full tutorial and download the source code you must be a member. (If you are already a member, log in here.)

Membership

Gain instant access to step-by-step visualization courses and tutorials for insight and presentation — all while supporting an independent site. Source code and data is included so that you can more easily apply what you learn in your own work.

Members also recieve a weekly newsletter, The Process, which looks more closely at the tools, the rules, and the guidelines and how they work in practice.

See samples of everything you gain access to:

About the Author

Nathan Yau is a statistician who works primarily with visualization. He earned his PhD in statistics from UCLA, is the author of two best-selling books — Data Points and Visualize This — and runs FlowingData. Introvert. Likes food. Likes beer.