title: Select data based on values in index pivottable
body: <p>I do have a Pivottable and would like to filter the index by values contained in the index. 
  I know how to do this for the the values greater 110 in the column "Value"</p>
  
  <pre><code>pd_pvt = pivot_table[(pivot_table['Value'] &gt; 110)]
  </code></pre>
  
  <p>How would you select data (bonds only) based on their name in the index?</p>
  
  <pre><code>pd_pvt = pivot_table[(index_name['Value'] == "Bonds")]
  </code></pre>
  
  <p>The code above won't work, as the index can't be treated as a column</p>