title: How to plot a PMF of a sample?
body: <p>Is there any function or library that would help me to plot a probability mass function of a sample the same way there is for plotting the probability density function of a sample ?</p>
  
  <p>For instance, using pandas, plotting a PDF is as simple as calling:</p>
  
  <pre><code>sample.plot(kind="density")
  </code></pre>
  
  <p>If there is no easy way, how can I compute the PMF so I could plot using matplotlib ?</p>