Very very cool. Is there a word for a directional graph in this circular form? Also, is every edge unidirectional, or are there some bidirectional edges? I would hope (and assume) there's nothing bidirectional, but...
From the looks of it that's been generated by `circo`, which is part of GraphViz and describes itself as a “filter for circular layout of graphs” and
circo draws graphs using a circular layout (see Six and Tollis, GD '99
and ALENEX '99, and Kaufmann and Wiese, GD '02.) The tool identifies
biconnected components and draws the nodes of the component on a cir‐
cle. The block‐cutpoint tree is then laid out using a recursive radial
algorithm. Edge crossings within a circle are minimized by placing as
many edges on the circle's perimeter as possible. In particular, if
the component is outerplanar, the component will have a planar layout.
If a node belongs to multiple non‐trivial biconnected components, the
layout puts the node in one of them. By default, this is the first non‐
trivial component found in the search from the root component.
Doing a bit more digging, it's using cytoscape[0] which is similar to graphviz. If you search your favorite search engine with "Cytoscape Session Viewer", you'll find many websites displaying the same type of graphs (select layout: circle).
