Graphs with multiple roots (i,e, more than one spatial graph).

[ucbpclw]

These can work in the code but at the moment it is set up so that each graph would need to be a different spatial graph file read in.
If there is one spatial graph containing multiple non-connected subgraphs then it could work but the code would need to be looped over each subgraph and the root node for each subgraph known.