title: Convert pandas json for highstock data format in a angularjs controller
body: <p>I'm breaking my head on how to convert from a json to the highstock array format for a Series chart.</p>
  
  <p>In my code I do the follow:</p>
  
  <pre><code>df2.reset_index().to_json(orient='records')
  </code></pre>
  
  <p>which results in this (for example):</p>
  
  <pre><code>[{"date":1456185600000,"adj_close":94.69},
  {"date":1456099200000,"adj_close":96.88},
  {"date":1455840000000,"adj_close":96.04},
  {"date":1455753600000,"adj_close":96.26}]
  </code></pre>
  
  <p>then I get that json at my angularjs controller as an array of Objects, and I don't know how to transform that to the highstock format, to this for example:</p>
  
  <pre><code> [
   [1456185600000, 94.69],
   [1456099200000, 96.88],
   [1455840000000, 96.04],
   [1455753600000, 96.26],
   ]
  </code></pre>
  
  <p>what should I do to make this conversion?</p>