title: How can I multiply two dataframes with different column labels in pandas?
body: <p>I'm trying to multiply (add/divide/etc.) two dataframes that have different column labels.</p>
  
  <p>I'm sure this is possible, but what's the best way to do it? I've tried using rename to change the columns on one df first, but (1) I'd rather not do that and (2) my real data has a multiindex on the columns (where only one layer of the multiindex is differently labeled), and rename seems tricky for that case...</p>
  
  <p>So to try and generalize my question, how can I get <code>df1 * df2</code> using <code>map</code> to define the columns to multiply together?</p>
  
  <pre><code>df1 = pd.DataFrame([1,2,3], index=['1', '2', '3'], columns=['a', 'b', 'c'])
  df2 = pd.DataFrame([4,5,6], index=['1', '2', '3'], columns=['d', 'e', 'f'])
  map = {'a': 'e', 'b': 'd', 'c': 'f'}
  
  df1 * df2 = ?
  </code></pre>