Use this if you are using igraph from R
Place vertices on a circle, in the order of their vertex ids.
layout_in_circle(graph, order = V(graph)) in_circle(...)
| graph | The input graph. | 
| order | The vertices to place on the circle, in the order of their desired placement. Vertices that are not included here will be placed at (0,0). | 
| ... | Passed to  | 
If you want to order the vertices differently, then permute them using the
permute function.
A numeric matrix with two columns, and one row for each vertex.
Gabor Csardi csardi.gabor@gmail.com
Other graph layouts: 
add_layout_(),
component_wise(),
layout_as_bipartite(),
layout_as_star(),
layout_as_tree(),
layout_nicely(),
layout_on_grid(),
layout_on_sphere(),
layout_randomly(),
layout_with_dh(),
layout_with_fr(),
layout_with_gem(),
layout_with_graphopt(),
layout_with_kk(),
layout_with_lgl(),
layout_with_mds(),
layout_with_sugiyama(),
layout_(),
merge_coords(),
norm_coords(),
normalize()
## Place vertices on a circle, order them according to their
## community
## Not run: 
library(igraphdata)
data(karate)
karate_groups <- cluster_optimal(karate)
coords <- layout_in_circle(karate, order =
          order(membership(karate_groups)))
V(karate)$label <- sub("Actor ", "", V(karate)$name)
V(karate)$label.color <- membership(karate_groups)
V(karate)$shape <- "none"
plot(karate, layout = coords)
## End(Not run)