The following post will guide you through the basics of hierarchical edge bundling. It explains what this kind of chart really is, describing step by step how to build it in
R with the
Start with a hierarchical network
Hierarchical Edge Bundling is based on a hierarchy. An original node gives underlying nodes and so on. Final nodes are called leaves, displayed around the circle.
Draw a connection
The second required level is connection, stored in another dataset. Leaves are connected with curves instead of straight lines.
You need at least 2 inputs for hierarchical edge bundling:
Connections data frame:
Hierarchical network data frame:
You can customize node and connection features to add more insight to the chart. For instance, you can change node color to highlight their belonging to a group, or connection color to represent its intensity
Color depending on value or index
Color can also depends on value to represent the strength of the connection, or on the the node index.
Last but not least, it is crucial to add labels to chart nodes. This is a bit tricky since label alignment and orientation must be computed by hand. This last example will teach you how to proceed, resulting in the figure below.Code