Hello,
I'm trying to intersection of multiple graphs where the graph objects are stored in a list.
For example,
library(igraph)
g1 <- graph.formula(A -- B -- C -- D)
g2 <- graph.formula(C -- E -- D -- C)
g3 <- graph.formula(B -- C -- D -- A)
listg <- list(g1, g2, g3)
If I mention individual graph objects separately, I obtain the desired result
intersection(listg[[1]], listg[[2]], listg[[3]], keep.all.vertices = FALSE)
IGRAPH UN-- 2 1 --
+ attr: name (v/c)
+ edge (vertex names):
[1] C--D
But I get the following error message when I use the list
intersection(listg, keep.all.vertices = FALSE)
Error in UseMethod("intersection") :
no applicable method for 'intersection' applied to an object of class "list"
Since, I need to perform intersection of a large number of graphs >20 with different combination, it is not feasible to type in individual graph objects separately.
Using a list would simplify my task to a greater extent.
Could you please let me know how to overcome this problem,?