title: Using symbol font / math notation in graphviz
body: <p>[Environment:  graphviz 2.38 / Windows 7]</p>
  
  <p>Using <code>dot</code>, I want to produce path diagrams like the following to represent a structural equation model (well, here, just a simple one-factor measurement model).  I'd like to use Greek letters for some nodes and edges, and would actually prefer if I could use LaTeX-like notation in the dot file like <code>\ksi</code>, <code>\lambda_1</code> or <code>\delta_1</code></p>
  
  <p><img src="https://i.stack.imgur.com/brSwK.png" alt="threevar"></p>
  
  <p>This diagram is supposed to represent the three equations </p>
  
  <pre><code>\begin{eqnarray*}
  x_{1i} &amp; = &amp; \lambda_1 \xi_{i} + \delta_{1i} \\
  x_{2i} &amp; = &amp; \lambda_2 \xi_{i} + \delta_{2i} \\
  x_{3i} &amp; = &amp; \lambda_3 \xi_{i} + \delta_{3i} 
  \end{eqnarray*}
  </code></pre>
  
  <p>The closest I've come to this is the following .dot file kludge, where I 
  chose font="Symbol" and replaced the Greek letters by their roman equivalents.  </p>
  
  <p>However, this doesn't work with <code>dot -Tpdf</code> or AFAICS any other devices other
  than Postscript <code>dot -Tps</code>, giving me an <code>.eps</code> file I have to convert to PDF or PNG.</p>
  
  <p>Question: is there anything better for this situation?</p>
  
  <pre><code>digraph threevar {
    rankdir=LR;
    size="8,4";
    node [fontname="Helvetica" fontsize=14 shape=box];
    edge [fontname="Symbol" fontsize=10];
    center=1;
    {rank=min k }
    {rank=same X1 X2 X3 }
    {rank=max z1 z2 z3 }
    z1 [shape=circle fontname="Symbol" label="d1"];
    z2 [shape=circle fontname="Symbol" label="d2"];
    z3 [shape=circle fontname="Symbol" label="d3"];
    k [fontname="Symbol" label="x" shape="ellipse"];
    k -&gt; X1 [label="l1"];
    k -&gt; X2 [label="l2"];
    k -&gt; X3 [label="l3"];
    z1 -&gt; X1;
    z2 -&gt; X2;
    z3 -&gt; X3;
  }
  </code></pre>