Package org.apache.commons.math.stat.univariate

Generic univariate summary statistic objects.

See:
          Description

Interface Summary
StorelessUnivariateStatistic Extends the capabilities of UnivariateStatistic with a statefull incremental strategy through three methods for calculating a statistic without having to maintain a double[] of the values.
UnivariateStatistic UnivariateStatistic interface provides methods to evaluate double[] based content using an implemented statistical approach.
 

Class Summary
AbstractStorelessUnivariateStatistic Abstract Implementation for StorelessUnivariateStatistics.
AbstractUnivariateStatistic Abstract Implementation for UnivariateStatistics.
 

Package org.apache.commons.math.stat.univariate Description

Generic univariate summary statistic objects.

UnivariateStatistic API Usage Examples:

UnivariateStatistic:

/* evaluation approach */
double[] values = new double[] { 1, 2, 3, 4, 5 };
UnivariateStatistic stat = new Mean();
System.out.println("mean = " + stat.evaluate(values));

StorelessUnivariateStatistic:

/* incremental approach */
double[] values = new double[] { 1, 2, 3, 4, 5 };
StorelessUnivariateStatistic stat = new Mean();
System.out.println("mean before adding a value is NaN = " + stat.getResult());
for (int i = 0; i < values.length; i++) {
    stat.increment(values[i]);
    System.out.println("current mean = " + stat2.getResult());
}
stat.clear();
System.out.println("mean after clear is NaN = " + stat.getResult());



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