title: pip freeze and order of dependencies
body: <pre><code>`pip freeze &gt; requirements.txt` 
  </code></pre>
  
  <p>automatically writes my dependencies in an apparently alphabetically order, like this:-</p>
  
  <pre><code>matplotlib==1.2.0
  numpy==1.6.2
  pandas==0.9.1
  </code></pre>
  
  <p>The problem with this is that <code>pip install -r requirements.txt</code> (when I deploy my code with its dependencies listed in <code>requirements.txt</code>) will end up failing because matplotlib needs numpy to be installed first.</p>
  
  <p>How can I ensure that matplotlib is listed <strong>after</strong> numpy in the <code>requirements.txt</code> file when I <code>pip freeze</code> it?</p>