Creating diagrams via the DiagrammeR package

The ggplot package greatly enhances R's plotting capabilities, but in some situations, this is not sufficient. In situations whenever we want to plot relationships between entities or elements, we need a different tool. Diagrams are well suited for this, but drawing them manually is very hard (since we need to draw each square or circle, plus the text, plus the relationships between the elements).

The DiagrammeR package allows us to create powerful diagrams, supporting the Graphviz syntax. Using it is actually simple. We will essentially define nodes, and we will then tell DiagrammeR how we want to connect those nodes. Of course, we can control the format of those diagrams (color, shapes, arrow types, themes, and so on).