在R中使用igraph找到另一个图形中遗漏的一个图形中的唯一边

Question

我创造了两个带有以下边缘的无向igraph

graph1 =＆gt; A--A，A--B和A--C

graph2 =＆gt; B--A，C--D，D--E和A--C

library(igraph)
my_data = data.frame(id1=c("A","A","A","B","C","A","D"),id2=c("A","B","C","A","D","C","E"))
graph1 = graph.data.frame(my_data[1:3,],directed=F)
graph2 = graph.data.frame(my_data[4:7,],directed=F)

我想找到graph2独有的边缘。因此，输出应该是：

# C--D D--E

Answer 1

你可以尝试

get.edgelist(graph2-graph1)
#      [,1] [,2]
# [1,] "C"  "D" 
# [2,] "D"  "E" 

或者，关于您的编辑：

E(graph2-graph1)
# + 2/2 edges (vertex names):
# [1] C--D D--E