Graphviz

Meta
1

This forum provides tools to generate graph images via a tool called GraphViz. For example, we could generate the following graph

hi hi there there hi--there

like so:

[graphviz]
graph {
  rankdir="LR"
  hi -- there
}
[/graphviz]

Here's a more complicated example:

[graphviz]
digraph {
  n0 [label="-"]
  n1 [label="^"]
  n2 [label="sin"]
  n3 [label="x"]
  n4 [label="2"]
  n5 [label="*"]
  n6 [label="2"]
  n7 [label="pi"]
  n8 [label="x"]
  n0 -> n1
  n0 -> n2
  n1 -> n3
  n1 -> n4
  n2 -> n5
  n5 -> n6
  n5 -> n7
  n5 -> n8
}
[/graphviz]

If you copy and paste that as input into forum post, you should see the following:

n0 - n1 ^ n0->n1 n2 sin n0->n2 n3 x n1->n3 n4 2 n1->n4 n5 * n2->n5 n6 2 n5->n6 n7 pi n5->n7 n8 x n5->n8

For what it's worth, that graph represents the abstract syntax tree of

x^2 - \sin(2\pi x).

you can read more about the dot language used to represent graphs on the GraphViz homepage.