title: What's the best way to sum all values in a Pandas dataframe?
body: <p>I figured out these two methods.  Is there a better one?</p>
  
  <pre><code>&gt;&gt;&gt; import pandas as pd
  &gt;&gt;&gt; df = pd.DataFrame({'A': [5, 6, 7], 'B': [7, 8, 9]})
  &gt;&gt;&gt; print df.sum().sum()
  42
  &gt;&gt;&gt; print df.values.sum()
  42
  </code></pre>
  
  <p>Just want to make sure I'm not missing something more obvious.</p>