title: large graph visualization with python and networkx
body: <p>I am having trouble with large graph visualization in python and <a href="http://networkx.github.io/" rel="noreferrer">networkx</a>. The graph is wish to visualize is directed, and has an edge and vertex set size of 215,000 From the documenation (which is linked at the top page) it is clear that networkx supports plotting with <code>matplotlib</code> and GraphViz. In <code>matplotlib</code> and networkx the drawing is done as follows:</p>
  
  <pre><code>import 
  networkx as nx
  import matplotlib.pyplot as plt
  #Let g be a graph that I created
  nx.draw(g)
  </code></pre>
  
  <p>I get a memory error after <code>nx.draw(g)</code>, afterwards you would normally do <code>plt.show()</code> or plt.[some_function] to save the file in a format for efficient and so forth.</p>
  
  <p>Next I tried GraphViz. From the <a href="http://en.wikipedia.org/wiki/Graphviz#Architecture" rel="noreferrer">wikipedia page</a> the <code>dot</code> format is used for directed graphs and I created a dot file:</p>
  
  <pre><code>nx.write_dot(g, "g.dot")
  </code></pre>
  
  <p>This worked well and I had a dot file in my current directory that is 12 megabytes. Next I ran the <code>dot</code> program (part of graphviz to create a postscript file):</p>
  
  <pre><code>dot -Tps g.dot -o g.ps
  </code></pre>
  
  <p>This slows down my computer, runs for a few minutes and then display <code>Killed</code> in the terminal. So it never could execute... While reading the documentation for graphviz it seems that only undirected graphs were supported for large graph visualization. </p>
  
  <p><strong>Question</strong>:
  With these two unsuccessful attempts can anyone show me how to visualize my large graph using python and networkx with about 215,000 vertices and 215,000 edges? I suspect as with Graphviz I will have to output into an intermediate format (although this shouldn't be that hard it won't be as easy as a builtin function) and then use another tool to read the intermediate format and then output a visualization.</p>
  
  <p>So, I am looking for the following:</p>
  
  <ol>
  <li>Output graph from networkx into an intermediate format</li>
  <li>With new package/software/tool (ideally python-interactive) read intermediate format and visualize the large graph</li>
  </ol>
  
  <p>If you need more information let me know!</p>