title: Forcing a node to stay on top when creating a cycle
body: <p>I have the following graph:</p>
  <pre><code>
  digraph G {
    u1, u2,  u3, u5 [ shape = oval, style=filled, fillcolor=&quot;palegreen&quot;];
  
    u3 -&gt; v3 -&gt; v5_0 -&gt; v5_1 -&gt; v1;
    u5 -&gt; v8 -&gt; v5_1;
    v1 -&gt; v5_2 -&gt; v2; 
    u1 -&gt; v2;
    v2 -&gt; u2;
  }
  </code></pre>
  <p><a href="https://i.stack.imgur.com/UzkXj.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/UzkXj.png" alt="enter image description here" /></a></p>
  <p>Now, I want <code>u2</code> and <code>u3</code> to be the same node, in the sense that I want the last vertex on the bottom to have an edge go up to u3 at the top of the rendered graph. But if I render:</p>
  <pre><code>digraph G {
    u1, u2,  u3, u5 [ shape = oval, style=filled, fillcolor=&quot;palegreen&quot;];
  
    u3 -&gt; v3 -&gt; v5_0 -&gt; v5_1 -&gt; v1;
    u5 -&gt; v8 -&gt; v5_1;
    v1 -&gt; v5_2 -&gt; v2; 
    u1 -&gt; v2;
    v2 -&gt; u3;
  }
  </code></pre>
  <p><a href="https://i.stack.imgur.com/sa8XF.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/sa8XF.png" alt="enter image description here" /></a></p>
  <p>The <code>u3</code> node ends up in the middle of the graph. How do I force <code>u3</code> to be at the top? I tried using <code>rank=min</code> on it, but that didn't help.</p>