title: How to handle date variable in machine learning data pre-processing
body: <p>I have a data-set that contains among other variables the time-stamp of the transaction in the format 26-09-2017 15:29:32. I need to find possible correlations and predictions of the sales (lets say in logistic regression). My questions are:</p>
  
  <ol>
  <li>How to handle the date format? Shall I convert it to one number (like excel does automatically)? Shall I split it in more variables like day, month, year, hour, mins, seconds? any other possible suggestions?</li>
  <li>What if I would like to add distinct week number per year? shall I add variable like 342017(week 34 of year 2017)?</li>
  <li>Shall I make the same for question 2 for quarter of year?</li>
  </ol>
  
  <blockquote>
  <pre><code>#         Datetime               Gender        Purchase
  1    23/09/2015 00:00:00           0             1
  2    23/09/2015 01:00:00           1             0
  3    25/09/2015 02:00:00           1             0
  4    27/09/2015 03:00:00           1             1
  5    28/09/2015 04:00:00           0             0
  </code></pre>
  </blockquote>