title: Set edge lengths according to weights in graphviz_layout
body: <p>I'm trying to use <code>networkx</code> to plot a weighted graph. I'm generating the positions of vertices using <code>graphviz_layout</code>. I want the edge lengths in the plot to be proportional to the edge weights I am using. Following is my code snippet to achieve this:</p>
  
  <pre><code>import networkx as nx
  from networkx.drawing.nx_agraph import graphviz_layout
  
  G = nx.Graph()
  G.add_weighted_edges_from(edgelist)
  pos = graphviz_layout(G)
  nx.draw_networkx(G, pos=pos)
  </code></pre>
  
  <p>This does not seem to impact edge lengths in the plot. I have seen <a href="https://stackoverflow.com/questions/10693088/passing-edge-weights-to-graphviz-layout-in-networkx">this post</a> however it only describes how to pass a single default weight for all edges to <code>graphviz_layout</code> (or perhaps I haven't understood the solution).</p>
  
  <p>How may I change my snippet to plot a graph with lengths proportional to edge weights?</p>
  
  <p>In the code snippet above, <code>edgelist</code> is a list of lists of this format:</p>
  
  <pre><code>edgelist = [[4, 219, 1.414], [4, 7, 3.86]]
  </code></pre>