title: Python:Pandas - Object to string type conversion in dataframe
body: <p>I'm trying to convert object to string in my dataframe using pandas.
  Having following data:</p>
  
  <pre><code>particulars
  NWCLG 545627 ASDASD KJKJKJ ASDASD
  TGS/ASDWWR42045645010009 2897/SDFSDFGHGWEWER
  dtype:object
  </code></pre>
  
  <p>while trying to convert particulars column from <strong>object to string</strong> using <strong>astype()[with str, |S, |S32, |S80] types</strong>, or directly <strong>using str functions</strong> it is not converting in string (remain object) and for <strong>str methods[replacing '/' with ' ']</strong> it says <code>AttributeError: 'DataFrame' object has no attribute 'str'</code></p>
  
  <p>using pandas 0.23.4</p>
  
  <p>Also refereed: <a href="https://github.com/pandas-dev/pandas/issues/18796" rel="nofollow noreferrer">https://github.com/pandas-dev/pandas/issues/18796</a></p>