title: Control Charts in Python
body: <p>I currently use R routinely for <a href="http://en.wikipedia.org/wiki/Statistical_process_control" rel="noreferrer">statistical process control</a>. With this I can produce <a href="http://en.wikipedia.org/wiki/Control_chart" rel="noreferrer">control charts</a> such as <a href="http://en.wikipedia.org/wiki/EWMA_chart" rel="noreferrer">EWMA</a>, Shewhart, <a href="http://en.wikipedia.org/wiki/CUSUM" rel="noreferrer">CUSUM</a> and <a href="http://en.wikipedia.org/wiki/Generalized_additive_model" rel="noreferrer">GAM</a> / <a href="http://en.wikipedia.org/wiki/Local_regression" rel="noreferrer">Loess</a> smoothing.</p>
  
  <p>Does anyone know of the best way to do these types of charts using Python? I initially looked at <a href="http://pytseries.sourceforge.net/" rel="noreferrer"><code>scikits.timeseries</code></a> but it has been canned to contribute to <a href="http://pandas.pydata.org/" rel="noreferrer">pandas</a>.</p>
  
  <p>I had a look at pandas and although it does have EWMA functionality, I need a little bit more. </p>