Dmitriy created MATH-1178: ----------------------------- Summary: Incorrect sample of usage of StatUtils at homepage Key: MATH-1178 URL: https://issues.apache.org/jira/browse/MATH-1178 Project: Commons Math Issue Type: Bug Environment: Documentation at http://commons.apache.org/proper/commons-math/userguide/stat.html Reporter: Dmitriy Priority: Trivial
At http://commons.apache.org/proper/commons-math/userguide/stat.html you are providing three ways to compute mean, std, median with DescriptiveStatistics, SummaryStatistics, StatUtils. But when you execute double std = StatUtils.variance(values), you are not actually get std in std, you get std*std, because DescriptiveStatistics actually returns FastMath.sqrt(getVariance()), but StatUtils returns variance directly. The solution is to substitute "double std = StatUtils.variance(values);" with "double std = FastMath.sqrt(StatUtils.variance(values));" -- This message was sent by Atlassian JIRA (v6.3.4#6332)