title: How to Sort Two Columns by Descending Order in Pandas?
body: <p>I have this dataframe <code>df</code> consisting of two columns <code>ID</code> and <code>Date</code>:</p>
  
  <pre><code>ID    Date
  4    1/1/2008
  3    1/1/2007
  2   9/23/2010
  2    6/3/1998
  2    1/1/2001 # Note this date should be before "6/3/1998" for ID# 2
  1   4/30/2003
  </code></pre>
  
  <p>I want to sort <code>df</code> by <code>ID</code> and <code>Date</code> in descending order (largest --> smallest), but this seems not working when I tried the following script:</p>
  
  <pre><code>print df.sort_values(by=["ID", "Date"], ascending=["False", "False"])
  </code></pre>
  
  <p>The output should in this descending order:</p>
  
  <pre><code>ID    Date
  4    1/1/2008
  3    1/1/2007
  2   9/23/2010
  2    1/1/2001 
  2    6/3/1998
  1   4/30/2003
  </code></pre>
  
  <p>Any idea how can I sort the date in the correct descending order?</p>