[igraph] Between-class network statistics

[Scott Chui]

Hello,

I am using igraph version 1.2.4.2 in R 3.5.2 on macOS 10.13 to analyse network 
data. The vertices have categorical attributes like “Sex” and “Age_class”, 
while the edges are undirected and weighted. I imported the adjacency matrix 
and attached the vertex attributes using the “set_vertex_attr” command. I would 
like to calculate network metrics such as betweenness and strength not only of 
the global network, but also between and within the attribute classes, i.e. to 
calculate betweenness of the weighted connection between female—female or 
male—female. 

I am able to calculated the within-class network statistics by removing 
vertices of other attribute class, e.g. 
>gM <- delete.vertices(g, V(g)[Sex != "M”])  ## network of only males
>betweenness(gM, direction = F)  ## betweenness of M—M

However, this method does not work on between-class statistics, I would like to 
know how can I calculate between-class statistics in igraph, thank you.

Best, 
Scott