R语言中igraph包的用法(邻接矩阵)

library(igraph)

g <- graph(c(1,1,1,2,1,2,1,2,1,5,2,3,2,4,2,5,3,3,3,4,3,4,3,4,4,5),directed = FALSE)
plot(g)

cell <- c(1,3,0,0,1,3,0,1,1,1,0,1,1,3,0,0,1,3,0,1,1,1,0,1,0)                                     
cell <- matrix(cell,5,5,byrow=T) 

cnames <- c('a','b','c','d','e')                                         
g <- graph.adjacency(cell,mode="undirected")plot(g,vertex.label=cnames)#绘出图像

#创建网络方法之一：data.frame
data<-data.frame(id1=c(1,1,2,3,4,4,5,5,6,6,7,8,8,9,10,5,15,6,7,16),id2=c(2,11,11,12,13,14,15,16,7,15,16,17,18,18,9,19,19,19,19,19))
g <- graph_from_data_frame(data, directed=FALSE)    #directed 参数控制graph 有无方向
g
IGRAPH UN-- 16 17 -- 
+ attr: name (v/c)
+ edges (vertex names):
 [1] 1 --2  2 --3  3 --4  1 --4  5 --7  5 --6  5 --8  7 --6  7 --8  6 --8  9 --10 9 --13 11--10 11--12 12--13 14--15 1 --16
#图形显示
plot(g)

#V(g)和E(g)可以用来查看网络g的节点和边
 V(g)
+ 16/16 vertices, named:
 [1] 1  2  3  5  7  6  9  11 12 14 16 4  8  10 13 15
E(g)
+ 17/17 edges (vertex names):
 [1] 1 --2  2 --3  3 --4  1 --4  5 --7  5 --6  5 --8  7 --6  7 --8  6 --8  9 --10 9 --13 11--10 11--12 12--13 14--15 1 --16
#但问题是怎么将里面的数据提取出来放到变量里面呢？
#节点提取有个函数get.vertex.attribute(g)
get.vertex.attribute(g)
$name
 [1] "1"  "2"  "3"  "5"  "7"  "6"  "9"  "11" "12" "14" "16" "4"  "8"  "10" "13" "15"
#查看类型可知是list
class(get.vertex.attribute(g))
[1] "list"
#剩下的就简单了
node<-get.vertex.attribute(g)[[1]]
node
 [1] "1"  "2"  "3"  "5"  "7"  "6"  "9"  "11" "12" "14" "16" "4"  "8"  "10" "13" "15"
#至于边呢？可以使用get.edgelist()
get.edgelist(g)
      [,1] [,2]
 [1,] "1"  "2" 
 [2,] "2"  "3" 
 [3,] "3"  "4" 
 [4,] "1"  "4" 
 [5,] "5"  "7" 
 [6,] "5"  "6" 
 [7,] "5"  "8" 
 [8,] "7"  "6" 
 [9,] "7"  "8" 
[10,] "6"  "8" 
[11,] "9"  "10"
[12,] "9"  "13"
[13,] "11" "10"
[14,] "11" "12"
[15,] "12" "13"
[16,] "14" "15"
[17,] "1"  "16"
#类型是matrix矩阵可以直接使用
class(get.edgelist(g))
[1] "matrix"