如何在igraph + R中保留节点位置

Question

如果我有以下图表，并使用向量设置节点的位置坐标：

library(igraph)
library(Cairo)

g9<- graph(c(0,1,0,2,0,3,1,4,1,2,3,4,3,5,4,5,5,2),n=6,dir=FALSE)
V(g9)$name<-c(1:6)
V(g9)$label<-V(g9)$name
coords <- c(0, 0, 1.00000000000000, 0,0.500000000000000, 0.866025403784439, 0.300000000000000, 0.200000000000000, 0.441421356237309, 0.341421356237310,0.248236190979496,0.393185165257814)
coords <- matrix(coords, 6,2,byrow=T)
plot(g9,layout=coords)

现在如果我添加以下代码，我需要重新设置坐标布局：

---

vc<-c(0,1,1,2,2,3,3,1)
gp<-graph(vc,dir=FALSE);
listSub<-graph.get.subisomorphisms.vf2(g9,gp)

m<-matrix(c(unlist(listSub)),length(listSub),length(unique(vc)),byrow=T)
md<-m[!duplicated(m[,1]),]

g<-delete.vertices(g9,c(m[1,2]))

dev.new()

coord <- c(0, 0, 1.00000000000000, 0,0.500000000000000, 0.866025403784439, 0.441421356237309, 0.341421356237310,0.248236190979496,0.393185165257814)
coord <- matrix(coord, 5,2,byrow=T)
plot(g,layout=coord)

我该如何将这些布局位置设为默认值，这样我就可以在不失去每个名称对应的位置的情况下对图表结构进行修改？

- user1310873

Answer 1

你可以保留初始的coord矩阵，只提取子图所需的行。

plot(g9, layout = coords[ V(g9)$name, ])
plot(g , layout = coords[  V(g)$name, ])

- Vincent Zoonekynd