title: Pandas convert dataframe to array of tuples
body: <p>I have manipulated some data using pandas and now I want to carry out a batch save back to the database. This requires me to convert the dataframe into an array of tuples, with each tuple corresponding to a "row" of the dataframe.</p>
  
  <p>My DataFrame looks something like:</p>
  
  <pre><code>In [182]: data_set
  Out[182]: 
    index data_date   data_1  data_2
  0  14303 2012-02-17  24.75   25.03 
  1  12009 2012-02-16  25.00   25.07 
  2  11830 2012-02-15  24.99   25.15 
  3  6274  2012-02-14  24.68   25.05 
  4  2302  2012-02-13  24.62   24.77 
  5  14085 2012-02-10  24.38   24.61 
  </code></pre>
  
  <p>I want to convert it to an array of tuples like:</p>
  
  <pre><code>[(datetime.date(2012,2,17),24.75,25.03),
  (datetime.date(2012,2,16),25.00,25.07),
  ...etc. ]
  </code></pre>
  
  <p>Any suggestion on how I can efficiently do this?</p>