title: spacing vertices evenly in igraph in r
body: <p>I have the following graph graph</p>
  
  <pre><code>set.seed(1410)
  df&lt;-data.frame(
  "site.x"=c(rep("a",3),rep("b",3),rep("c",3),rep("d",3)),
  "site.y"=c(rep(c("e","f","g"),4)),
  "bond.strength"=sample(1:100,12, replace=TRUE))
  
  library(igraph)
  df&lt;-graph.data.frame(df)
  V(df)$names &lt;- c("a","b","c","d","e","f","g")
  layOUT&lt;-data.frame(x=c(rep(1,4),rep(2,3)),y=c(4:1,3:1))
  E(df)[ bond.strength &lt; 101 ]$color &lt;- "red"
  E(df)[ bond.strength &lt; 67 ]$color &lt;- "yellow"
  E(df)[ bond.strength &lt; 34 ]$color &lt;- "green"
  V(df)$color &lt;- "white"
  l&lt;-as.matrix(layOUT)
  plot(df,layout=l,vertex.size=10,vertex.label=V(df)$names,
  edge.arrow.size=0.01,vertex.label.color = "black")
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/NWmkh.png" alt="enter image description here"></p>
  
  <p>I would like to space the vertices "g-e" evenly along the vertical distance between vertex a and d to make my current graph (see below) prettier. As you can see it is pretty crowded. </p>
  
  <p><img src="https://i.stack.imgur.com/7nw2d.png" alt="enter image description here"></p>
  
  <p>Also I would like to move the two column of vertices closer together on the x-axis but I have noticed that adjusting the x coordinates in the layout is not responding. For example the two following layouts produce graph that look exactly the same despite the drastic adjustment in the x-coordinates. </p>
  
  <pre><code>layOUT&lt;-data.frame(x=c(rep(1,4),rep(2,3)),y=c(4:1,3:1))
  
  layOUT&lt;-data.frame(x=c(rep(1,4),rep(100,3)),y=c(4:1,3:1)) 
  </code></pre>
  
  <p>Thanks for any advice you may have.</p>