Four examples are provided in the GraphSynth download, and more will be available soon for more complicated (albeit mechanical engineering) applications.
SeedBurst is an interesting an example of both parametric recognize and choose functions. Given a seed that is a single node, the four rules of SeedBurst create a unique tree for the integer where each leaf of the tree is represented with a value of “1”. One additional thing to notice about this system, is that the rule set is Automatic and not Design (see description on rule set page).
Route is an example of how more than one rule set can work together to create a candidate solution. Here, the first rule set transitions the graph from just a list of unconnected nodes to a spanning tree (the minimum spanning tree is easily identified with Prim’s or Kruskal’s algorithm which could be implemented in an intelligent choosing function—that minimum spanning tree is shown in the output directory). Afterwards, we would like to add additional routes between cities for convenience in traveling from any location to any other location. The two rule sets will create a random candidate—”you’re free to move about the country”.