title: ValueError: The truth value of a Series is ambiguous while checking the boolean column value
body: <p>My dataframe contain one column with boolean values i.e 0 or 1.
  I am trying to check if its 0, then increment the counter for <code>count_0</code> else increment for <code>count_1</code>.</p>
  
  <pre><code>if(df1['Project_is_approved']==0):
      count_0 = count_0 + 1;
  if(df1['Project_is_approved']==1):
      count_1 = count_1 + 1;
  </code></pre>
  
  <p>Either <code>count_0</code> or <code>count_1</code> should increment.
  Instead i am getting error at,</p>
  
  <pre><code>if(df1['Project_is_approved']==0):
  </code></pre>
  
  <p>Error:</p>
  
  <pre><code>ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().
  </code></pre>