title: Graphviz ignore edge when deciding layout
body: <p>I have an edge in a dot graph that I need to be ignored by other edges during the layout. I have tried feeding the first part of the code through <code>dot</code> and then adding dotted edges below, however the other solid edges still keep being affected by them.</p>
  <p>The code:</p>
  <pre><code>digraph structs {
      rankdir=LR
      edge [tailclip=false];
      node [shape=record];
      header [label=&quot;{&lt;0&gt; |&lt;1&gt; header|&lt;2&gt;  }&quot;];
      data0 [label=&quot;{&lt;0&gt; |&lt;1&gt; data0|&lt;2&gt; }&quot;];
      data1 [label=&quot;{&lt;0&gt; |&lt;1&gt; data1|&lt;2&gt; }&quot;];
      trailer [label=&quot;{&lt;0&gt; |&lt;1&gt; trailer|&lt;2&gt; }&quot;];
  
      header -&gt; data0 -&gt; data1 -&gt; trailer [style=invis, weight=100];
      edge [arrowhead=vee, arrowtail=dot, dir=both, weight=40];
      header:2:c -&gt; data0:1:n;
      data0:0:c -&gt; header:1:s;
  
  
      data0:2:c -&gt; data1:1:n;
      data1:0:c -&gt; data0:1:s;
  
      data1:2:c -&gt; trailer:1:n ;
      trailer:0:c -&gt; data1:1:s;
  
      edge [constraint=false, style=dashed, weight=0, layer=1];
      data0:2:c -&gt; trailer:1:n [weight=0];
      trailer:0:c -&gt; data0:1:s [weight=0];
  
  }
  </code></pre>
  <p>The results:
  <a href="https://i.stack.imgur.com/BqhuE.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/BqhuE.png" alt="The result" /></a></p>