Convert a column of datetimes to epoch in Python : <p>I'm currently having an issue with Python. I have a Pandas DataFrame and one of the columns is a string with a date.
The format is :</p>

<blockquote>
  <p>"%Y-%m-%d %H:%m:00.000". For example : "2011-04-24 01:30:00.000"</p>
</blockquote>

<p>I need to convert the entire column to integers. I tried to run this code, but it is extremely slow and I have a few million rows.</p>

<pre><code>    for i in range(calls.shape[0]):
        calls['dateint'][i] = int(time.mktime(time.strptime(calls.DATE[i], "%Y-%m-%d %H:%M:00.000")))
</code></pre>

<p>Do you guys know how to convert the whole column to epoch time ?</p>

<p>Thanks in advance !</p>
