Create grouped edge lists - r

Question

I have a list of people and I want to examine the characteristics of their collaborative networks. However, I want to use all the edges of their networks, not just the edges that are directly connected to them. For example, let's say that I am looking at Bob's network. For Project1, Bob, Bill, and Jane worked together.
If I only cared about the edges connected to Bob, then my edge list would be: Bob--Bill, Bob--Jane. The network would have 0 triangles. However, if I looked at all the edges for Bob's network, the edge list would look like this: Bob--Bill, Bob--Jane, Bill--Jane. The network would have 1 triangle.
The only way to do this that I can think of is to create a "grouped" edge list. I'm just not sure how to tackle it.
My edge data looks like this:
collab <- data.frame(vertex1 = c("Bob","Bill","Bob","Jane","Bill","Jane","Bob","Jane","Bob","Bill","Bob"
,"Jane","Bill","Jane","Bob","Jane","Jane","Jill","Jane","Susan","Susan"),
edgeID = c(1,1,1,1,1,1,2,2,1,1,1,1,1,1,2,2,3,3,3,3,3),
vertex2 = c("Bill","Bob","Jane","Bob","Jane","Jill","Jane","Bob","Bill","Bob"
,"Jane","Bob","Jane","Bill","Jane","Bob","Jill","Jane","Susan","Jane","Jill"))
vertex1 edgeID vertex2
1 Bob 1 Bill
2 Bill 1 Bob
3 Bob 1 Jane
4 Jane 1 Bob
5 Bill 1 Jane
6 Jane 1 Jill
7 Bob 2 Jane
8 Jane 2 Bob
9 Jane 3 Jill
10 Jill 3 Jane
11 Jane 3 Susan
12 Susan 3 Jane
13 Susan 3 Jill
I have another vector that holds the names of my target people:
targets <- data.frame(name=c("Bob","Jane"))
What I'd like to do is group the relevant edges under the appropriate targets such that the result is something like:
group vertex1 edgeID vertex2
1 Bob Bob 1 Bill
2 Bob Bill 1 Bob
3 Bob Bob 1 Jane
4 Bob Jane 1 Bob
5 Bob Bill 1 Jane
6 Bob Jane 1 Jill
7 Bob Bob 2 Jane
8 Bob Jane 2 Bob
9 Jane Bob 1 Bill
10 Jane Bill 1 Bob
11 Jane Bob 1 Jane
12 Jane Jane 1 Bob
13 Jane Bill 1 Jane
14 Jane Jane 1 Bill
15 Jane Bob 2 Jane
16 Jane Jane 2 Bob
17 Jane Jane 3 Jill
18 Jane Jill 3 Jane
19 Jane Jane 3 Susan
20 Jane Susan 3 Jane
21 Jane Susan 3 Jill
I figure that if I can get here, I can make a for loop that cycles through each target, creates a graph with iGraph, and calculates the network metrics for Bob and Jane without much issue. Am I going about this the right way or does iGraph have a better way to do this?

Answer 1

Here might be one option
g <- graph_from_data_frame(collab[c(1, 3, 2)], directed = FALSE)
do.call(
rbind,
c(
make.row.names = FALSE,
lapply(
targets$name,
function(nm) {
z <- c(nm, V(g)$name[distances(g, nm) == 1])
cbind(group = nm, unique(subset(collab, vertex1 %in% z & vertex2 %in% z)))
}
)
)
)
which gives
group vertex1 edgeID vertex2
1 Bob Bob 1 Bill
2 Bob Bill 1 Bob
3 Bob Bob 1 Jane
4 Bob Jane 1 Bob
5 Bob Bill 1 Jane
6 Bob Bob 2 Jane
7 Bob Jane 2 Bob
8 Bob Jane 1 Bill
9 Jane Bob 1 Bill
10 Jane Bill 1 Bob
11 Jane Bob 1 Jane
12 Jane Jane 1 Bob
13 Jane Bill 1 Jane
14 Jane Jane 1 Jill
15 Jane Bob 2 Jane
16 Jane Jane 2 Bob
17 Jane Jane 1 Bill
18 Jane Jane 3 Jill
19 Jane Jill 3 Jane
20 Jane Jane 3 Susan
21 Jane Susan 3 Jane
22 Jane Susan 3 Jill