title: How do I plot a step function with Matplotlib in Python?
body: <p>This should be easy but I have just started toying with matplotlib and python. I can do a line or a scatter plot but i am not sure how to do a simple step function. Any help is much appreciated.</p>
  
  <pre><code>x = 1,2,3,4
  y = 0.002871972681775004, 0.00514787917410944, 0.00863476098280219, 0.012003316194034325
  </code></pre>