radial layout with groups

radial_grp_layout.R

library(igraph)
library(smglr)
library(tidyverse)
library(ggraph)
g <- sample_islands(9,40,0.2,10)
g <- simplify(g)
V(g)$grp <- rep(1:9,each=40)
el <- get.edgelist(g)
E(g)$col <- case_when(
V(g)$grp[el[,1]]==1 & V(g)$grp[el[,2]]  == 1 ~ 1,
V(g)$grp[el[,1]]==2 & V(g)$grp[el[,2]]  == 2 ~ 2,
V(g)$grp[el[,1]]==3 & V(g)$grp[el[,2]]  == 3 ~ 3,
V(g)$grp[el[,1]]==4 & V(g)$grp[el[,2]]  == 4 ~ 4,
V(g)$grp[el[,1]]==5 & V(g)$grp[el[,2]]  == 5 ~ 5,
V(g)$grp[el[,1]]==6 & V(g)$grp[el[,2]]  == 6 ~ 6,
V(g)$grp[el[,1]]==7 & V(g)$grp[el[,2]]  == 7 ~ 7,
V(g)$grp[el[,1]]==8 & V(g)$grp[el[,2]]  == 8 ~ 8,
V(g)$grp[el[,1]]==9 & V(g)$grp[el[,2]]  == 9 ~ 9,
TRUE ~ 10
)

xy <- layout_with_centrality(g,V(g)$grp)
ggraph(g,layout = "manual",node.positions = data.frame(x = xy[,1], y = xy[,2])) +
  geom_edge_link(aes(col=factor(col)),n=2,alpha=0.4)+
  geom_node_point(aes(fill=factor(grp)),shape=21)+
  theme_graph()+
  coord_fixed()+
  scale_fill_manual(values = c("#458B74", "#8A2BE2", "#CD3333", "#8B7355", "#458B00",
                               "#EE7600", "#FF6EB4", "#CDCD00", "#6495ED"))+
  scale_edge_color_manual(values = c("#458B74", "#8A2BE2", "#CD3333", "#8B7355", "#458B00",
                                     "#EE7600", "#FF6EB4", "#CDCD00", "#6495ED","grey66"))+
  theme(legend.position = "none")