Heat Maps are intended to show the data points which are contained in a matrix and colored in accordance with a range they belong to. These charts can be used for showing an array of points representing different states of an object or in other cases when we need to order our data in a table. Heat Maps use standard two-dimensional coordinate system.
This example demonstrates the Mendeleev’s periodic table. Each point represents an element with a lot of extra information, which appears in tooltips when we hover the elements: the category this element belongs to, its period, group and atomic number, also its alias and name in the tooltip title. Not all “cells” of a table are filled due to specific appearance of the periodic table. Axes are turned off, but the legend is on and it is placed to the right from the table. You can use its items to manage the elements: to highlight all elements of one category hover the legend item of this category, and to select all items of one category, click at the corresponding legend item. You can also use the table elements itself: a click at the element will select it, but if you hold the Shift or Ctrl key while clicking, you will be able to select plenty of elements. When you hover an element, it becomes filled with grey, gets a bold white stroke and shows the tooltip with some extra information. Note that this example uses string values (categories) as ranges, so there is no numeric value each element represents.