title: Selectively populating a pandas column depending if the value in a different column falls into a list
body: <p>I have a pandas dataframe with names of small geographic areas in one column. I have developed a set of rules that define which of these areas fall into what larger regions. Since every rule is a condition, I have tried using np.select, but I keep getting a mistake.</p>
  
  <p>This is what I have tried:</p>
  
  <pre><code>Okanagan_and_Kootenays = ['Columbia-Shuswap','Central Okanagan', 'North Okanagan', 'Okanagan-Similkameen', 'East Kootenay', 'Kootenay Boundary','Central Kootenay' ]
  
  conditions = [(main_file['long_name'] == Okanagan_and_Kootenays)]
  choices = 'Okanagan_and_Kootenays'
  
  main_file['_area_large'] = np.select(conditions, choices)  
  </code></pre>
  
  <p>And I get the following error every time:</p>
  
  <p><code>ValueError: Arrays were different lengths: 1412 vs 7</code></p>