How to create a directed network graph with aligned nodes in R?

Question

I would like to get something like this

A network graph with or without labels but with nodes aligned. How can I get it?

I'm already used the packages Diagrammer and Visnetwork for other graphs, so using the same will be a bonus.

library(DiagrammeR)
library(visNetwork)

from=c("A","A","A","A","B","B","B","C","C","D")
to=c("B","C","D","E","C","D","E","D","E","E")
nodesd=c("A","B","C","D","E")

With Diagrammer:

nodes <- create_node_df(  n=length(nodesd), label=nodesd,  width=0.3) 
edges <- create_edge_df(from = factor(from, levels=nodesd), to = factor(to, levels=nodesd), rel = "leading_to")   
graph <- create_graph(nodes_df = nodes, edges_df = edges)
render_graph(graph)

I've also tried with set_node_position() but it doesn't seem to make any difference.

With Visnetwork

nodes <- data.frame(id=nodesd, label= nodesd ) 
edges <- data.frame(from=from, to =to, length=150)
visNetwork(nodes,edges, width="100%" , height="100%")  %>% 
visNodes(shape = "circle") %>%  visEdges(arrows = 'to', smooth =T)  

As you can see the nodes are not aligned. How can I force it to do it?

I could drag them manually but it's not something you want to do if you have many graphs, and the result is not good anyway.

I got to do it vertically with visnetwork by adding the line

  %>%   visHierarchicalLayout()

at the end. But it doesn't work well because many edges disappear.

If I want to get a horizontal alignement I need to add this to the nodes definition.

level = c(1,1,1,1,1)

Answer 1

I can't help you with DiagrammeR or visNetwork, but it is easy to do this with igraph. You just need to specify a simple layout of the nodes. You will also want to adjust the curvature of the edges. My example below has something that works, but you might adjust it to make it more artistic.

library(igraph)
EL = cbind(from, to)
g = graph_from_edgelist(EL)

L = cbind(1:5, 5:1)
CURVE = c(0,0.15, 0.3, 0.45, 0, -0.15, -0.3, 0, 0.15, 0) 
plot(g, layout=L, edge.curved=CURVE)