Heat map

Heat map generated from DNA microarray data reflecting gene expression values in several conditions
A heat map showing the RF coverage of a drone detection system

A heat map (or heatmap) is a 2-dimensional data visualization technique that represents the magnitude of individual values within a dataset as a color. The variation in color may be by hue or intensity.

In some applications such as crime analytics or website click-tracking, color is used to represent the density of data points rather than a value associated with each point.

"Heat map" is a relatively new term, but the practice of shading matrices has existed for over a century.[1]

  1. ^ Wilkinson L, Friendly M (May 2009). "The History of the Cluster Heat Map". The American Statistician. 63 (2): 179–184. CiteSeerX 10.1.1.165.7924. doi:10.1198/tas.2009.0033. S2CID 122792460.