Optimizer for a generalization of Newman and Girvan's Modularity measure,
for computing graph clusterings.
The Modularity measure is generalized to arbitrary node weights;
it is recommended to set the weight of each node to its degree,
i.e. the total weight of its edges, as Newman and Girvan did.
For more information on the (used version of the) Modularity measure, see
M. E. J. Newman: "Analysis of weighted networks",
Physical Review E 70, 056131, 2004.
For the relation of Modularity to the LinLog energy model, see
Andreas Noack:
"Modularity clustering is force-directed layout",
Preprint arXiv:0807.4052, 2008.