title: Crown graph in graphviz - how to preserve order correctly?
body: <p>I've written the following graphviz code to draw a crown graph on 8 nodes:</p>
  
  <pre><code>graph G {
    u1 [label=&lt;&lt;I&gt;u&lt;SUB&gt;1&lt;/SUB&gt;&lt;/I&gt;&gt;]
    v1 [label=&lt;&lt;I&gt;v&lt;SUB&gt;1&lt;/SUB&gt;&lt;/I&gt;&gt;]
    u2 [label=&lt;&lt;I&gt;u&lt;SUB&gt;2&lt;/SUB&gt;&lt;/I&gt;&gt;]
    v2 [label=&lt;&lt;I&gt;v&lt;SUB&gt;2&lt;/SUB&gt;&lt;/I&gt;&gt;]
    u3 [label=&lt;&lt;I&gt;u&lt;SUB&gt;3&lt;/SUB&gt;&lt;/I&gt;&gt;]
    v3 [label=&lt;&lt;I&gt;v&lt;SUB&gt;3&lt;/SUB&gt;&lt;/I&gt;&gt;]
    u4 [label=&lt;&lt;I&gt;u&lt;SUB&gt;4&lt;/SUB&gt;&lt;/I&gt;&gt;]
    v4 [label=&lt;&lt;I&gt;v&lt;SUB&gt;4&lt;/SUB&gt;&lt;/I&gt;&gt;]
    u1 -- v2 
    u1 -- v3 
    u1 -- v4
    u2 -- v1
    u2 -- v3
    u2 -- v4
    u3 -- v1
    u3 -- v2
    u3 -- v4
    u4 -- v1
    u4 -- v2
    u4 -- v3
  }
  </code></pre>
  
  <p>The result when compiled with <code>dot</code> is good, but not quite what I want - I need the order of the top 'layer' of nodes to be <code>u_1, u_2, u_3, u_4</code>, and the bottom layer to be <code>v_1, v_2, v_3, v_4</code>, so that it can look like a crown graph. However, I'm not sure how to tell <code>dot</code> to do this. Any help would be awesome.</p>