title: pandas timestamp series to string?
body: <p>I am new to python (coming from R), and I am trying to understand how I can convert a timestamp series in a pandas dataframe (in my case this is called <code>df['timestamp']</code>) into what I would call a string vector in R.  is this possible?  How would this be done?</p>
  
  <p>I tried <code>df['timestamp'].apply('str')</code>, but this seems to simply put the entire column <code>df['timestamp']</code> into one long string.  I'm looking to convert each element into a string and preserve the structure, so that it's still a vector (or maybe this a called an array?)</p>