[igraph] igraph_community_leading_eigenvector_step implementation

[Al]

Hi

I am a developer tasked with generalizing the implementation of the M.
Newman community detection algorithm to accept weighted edges. We want
to use the step wise variation of the function (located in
communities.c under the igraph_community_leading_eigenvector_step
function). On inspection of the source code, it is not obvious to me
that he modularity calculation is actually being preformed. However,
in the non-step was variation of the function
(igraph_community_leading_eigenvector), I notice that it is properly
implemented. So I am wondering if the step wise variation is properly
implemented? and if so maybe some insight could be shed on where it is
preforming the M. Newman modularity calculation.

Thanks
Al Tucker