A heat map is a graphical representation of data where the individual values contained in a matrix are represented as colors.
Heat maps require the modules/heatmap.js file to be loaded.
The heat map series is defined by setting the type to
heatmap. A heat map has an X and Y axis like any cartesian series. The point definitions however, take three values,
y as well as
value, which serves as the value for color coding the point. These values can also be given as an array of three numbers.
Heat maps borrow a central concept from Highcharts Maps, the color axis. See the docs article on color axis for details
See heatmap in the Highcharts Maps docs.