Package org.apache.commons.math.stat.descriptive
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());

Interface Summary Interface Description StatisticalMultivariateSummary Reporting interface for basic multivariate statistics.StatisticalSummary Reporting interface for basic univariate statistics.StorelessUnivariateStatistic Extends the definition ofUnivariateStatistic
withStorelessUnivariateStatistic.increment(double)
andStorelessUnivariateStatistic.incrementAll(double[])
methods for adding values and updating internal state.UnivariateStatistic Base interface implemented by all statistics.WeightedEvaluation Weighted evaluation for statistics. 
Class Summary Class Description AbstractStorelessUnivariateStatistic Abstract implementation of theStorelessUnivariateStatistic
interface.AbstractUnivariateStatistic Abstract base class for all implementations of theUnivariateStatistic
interface.AggregateSummaryStatistics An aggregator forSummaryStatistics
from several data sets or data set partitions.DescriptiveStatistics Maintains a dataset of values of a single variable and computes descriptive statistics based on stored data.MultivariateSummaryStatistics Computes summary statistics for a stream of ntuples added using theaddValue
method.StatisticalSummaryValues Value object representing the results of a univariate statistical summary.SummaryStatistics Computes summary statistics for a stream of data values added using theaddValue
method.SynchronizedDescriptiveStatistics Implementation ofDescriptiveStatistics
that is safe to use in a multithreaded environment.SynchronizedMultivariateSummaryStatistics Implementation ofMultivariateSummaryStatistics
that is safe to use in a multithreaded environment.SynchronizedSummaryStatistics Implementation ofSummaryStatistics
that is safe to use in a multithreaded environment.