Learning D3.js 5 Mapping - Second Edition

An example with viz.js

To see this in practice, let's take a look at the scripts/viz.js program as a template for creating testable code for the data manipulation functions in the visualization. For this example, we will create a set of simple bars that are based on the profit of an arbitrary dataset. We are given the sales and cost in the data; however, we need to determine the profit for the visualization by subtracting the sales from the cost. In this contrived example, we need a few small helper functions, which are as follows:

• A function to take the original dataset and return a new dataset with the profit calculated
• A function to retrieve an array of unique categories to apply to an ordinal scale
• A function to determine the maximum ...