An example illustrating a scale that allows the ranges to be adjusted by the user.
This example is based on this one.
This example demonstrates how to construct a key from a threshold scale, in the style of Ford Fessenden’s map of police stops involving force. A linear scale is used to set the x-position of each colored rectangle in the key. There is one rectangle per color in the threshold scale’s range, and one tick per value in the threshold scale’s domain. The linear scale’s domain sets the implied extent of the key, here spanning 0 to 100%.
