Creating images for visualization

Now, we’re moving from calculations and data editing to something we can see! We’ll begin by creating different types of maps. In Chapter 1, Learning about Geospatial Analysis with Python, we visualized our SimpleGIS program using the Tkinter module that’s included with Python. In Chapter 4, Geospatial Python Toolbox, we examined a few other methods for creating images. Now, we’ll examine these tools in more depth by creating two specific types of thematic maps. The first is a dot density map and the second is a choropleth map.

First, let’s start with the dot density map.

Dot density calculations

A dot density map shows concentrations of subjects within a given area. If an area is divided up into polygons containing statistical information, you can model that information using randomly distributed dots within that area using a fixed ratio across the dataset. This type of map is commonly used for population...