title: Get median from number series using Apache Commons Math
body: <p>Using Apache Commons Math, how do I get the median from a series of numbers?</p>
  
  <p>The <a href="http://commons.apache.org/proper/commons-math/userguide/stat.html">Commons Math User Guide</a> says <code>DescriptiveStatistics</code> supports median, yet the <a href="http://commons.apache.org/proper/commons-math/apidocs/org/apache/commons/math3/stat/descriptive/DescriptiveStatistics.html">JavaDocs for DescriptiveStatistics</a> makes no mention of it. It does mention geometric mean, is this the same thing as median?</p>
  
  <p>I do see <code>getPercentile(double)</code>. Is <code>getPercentile(50)</code> the same as median?</p>