title: Pandas Python Regex : error: nothing to repeat
body: <p>I have a dataframe with a couple of strange characters, "*" and "-". </p>
  
  <pre><code>import pandas as pd
  import numpy as np
  
  data = {'year': [2010, 2011, 2012, 2011, 2012, 2010, 2011, 2012],
          'team': ['Bears', 'Bears', 'Bears', 'Packers', 'Packers', 'Lions',     'Lions', 'Lions'],
          'wins': [11, '*', 10, '-', 11, 6, 10, 4],
          'losses': [5, 8, 6, 1, 5, 10, 6, 12]}
  football = pd.DataFrame(data, columns=['year', 'team', 'wins', 'losses'])
  </code></pre>
  
  <p>I would like to replace the strange characters with '0.00' but I get an error -</p>
  
  <pre><code>error: nothing to repeat
  </code></pre>
  
  <p>I understand this is linked to regex but I still dont know how to overcome the issue.</p>
  
  <p>the code I use to replace the characters:</p>
  
  <pre><code>football.replace(['*','-'], ['0.00','0.00'], regex=True).astype(np.float64)
  </code></pre>