Triangle Counting
Counting triangles can measure the connectedness of a graph or subgraph. Graphs are treated as undirected in GraphX. GraphX collapse duplicate edges into one [1,2]. The more connected a graph is, the more triangles it has.
References
Gonzalez, J. E., Xin, R. S., Dave, A., Crankshaw, D., Franklin, M. J., Gonzalez, J. E., … Stoica, I. (2014). GraphX : Graph Processing in a Distributed Dataflow Framework. 11th USENIX Symposium on Operating Systems Design and Implementation, 599–613. Retrieved from https://www.usenix.org/conference/osdi14/technical-sessions/presentation/gonzalez
Malak, M., & East, R. (2016). Spark GraphX in Action. Manning.