how to convert a float/integer into a date with strptime?
<p>I have a pandas dataframe that contains the following columns:</p>

<pre><code>col1 col2
20040929 NaN
NaN 20040925 
</code></pre>

<p>that is both both col1 and col2 are float64 (or int64) numbers.
I am trying to convert these using datetime.strptime() but I get the error</p>

<blockquote>
  <p>"cannot convert the series to type 'float'"</p>
</blockquote>

<p>and if I convert them to float, I get something like 20040929.0 which strptime does not understand.</p>

<p>How can I transform these columns into date then?
Many thanks</p>