title: Format of datetime in pyplot axis
body: <p>I am trying to plot some data against a list of <code>datetime</code> objects in the x axis with pyplot. However the dates appear as the standard format, which is <code>%Y-%m-%d %H:%M:%S</code> (way too long). I can circumvent this by creating a list of date strings with <code>strftime</code> and use that instead. I also know that there is some kind of <code>date</code> object intrinsic for <code>pyplot</code> which I could use instead of <code>datetime</code>.</p>
  
  <p>Is there a way to tell <code>pyplot</code> in which format to plot the <code>datetime</code>objects however? Without having to transform everything to string or another kind of object?</p>
  
  <p>Thank you.</p>