Choosing a circular barplot
Very often, we need to display the measures associated with different categorical entities using a bar chart (or barplot). However, when the number of entities to be represented exceeds 15 or 20, the graph begins to become unreadable, even if it is arranged vertically:
Figure 21.1: A barplot of worldwide weapons sellers
In this case, as you saw in Chapter 19, Exploratory Data Analysis, it is often a good idea to plot a maximum number of entities and then group the subsequent entities into a single category (in our case, the Others category). This preserves the readability of the graph, but loses some of the information you want to represent.
If it is absolutely necessary to display all entities with all their dimensions, we often resort to a more eye-catching organization of the space occupied by the barplot, wrapping it in a circular shape, thus obtaining a circular barplot:
Figure 21.2: Circular barplot of worldwide weapons sellers...
