I stumbled (here, in the expression for the block diagram) upon a version of Graph that I don't see in the documentation over here. That documentation admits three overloads (the following are in my own words):
Graph[{
edges}]
Graph[{
vertices}, {
edges}]
Graph[{
decoratedVertices}, {
decoratedEdges}]
For instance, the following example invokes overload 2:
Graph[{1,2,3}, {{1, 2}, {1, 3}, {2, 3}}]
If I add a Null
in an undocumented place, I get arrows:
Graph[{1,2,3}, { {{1, 2}, {1, 3}, {2, 3}}, Null } ]
Notice there is an extra level of List
in the list of vertices. It's as though the list of vertices contains a nested list of vertices and a Null vertex.
This seems to produce similar results to
Graph[{1, 2, 3}, {1 \[DirectedEdge] 2, 1 \[DirectedEdge] 3, 2 \[DirectedEdge] 3}]
Anyone happen to know what's going on? I'm ok with blindly using the cool feature, but I wonder what the other options for this API might be.