* {@link PairedStatsAccumulator#snapshot} method which returns {@link PairedStats} instances, see
 * {@link PairedStatsTest}.
 *
 * @author Pete Gillin
 */
@NullUnmarked
public class PairedStatsAccumulatorTest extends TestCase {

  private PairedStatsAccumulator emptyAccumulator;
  private PairedStatsAccumulator emptyAccumulatorByAddAllEmptyPairedStats;

/**
 * A mutable object which accumulates paired double values (e.g. points on a plane) and tracks some
 * basic statistics over all the values added so far. This class is not thread safe.
 *
 * @author Pete Gillin
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class PairedStatsAccumulator {
  /** Creates a new accumulator. */
  public PairedStatsAccumulator() {}

/**
 * An immutable value object capturing some basic statistics about a collection of paired double
 * values (e.g. points on a plane). Build instances with {@link PairedStatsAccumulator#snapshot}.
 *
 * @author Pete Gillin
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class PairedStats implements Serializable {

  private final Stats xStats;
  private final Stats yStats;

import java.util.Random;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@link Quantiles}.
 *
 * @author Pete Gillin
 */
@NullUnmarked
public class QuantilesTest extends TestCase {

  /*
   * Since Quantiles provides a fluent-style API, each test covers a chain of methods resulting in

import java.util.Random;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Tests for {@link Quantiles}.
 *
 * @author Pete Gillin
 */
@NullUnmarked
public class QuantilesTest extends TestCase {

  /*
   * Since Quantiles provides a fluent-style API, each test covers a chain of methods resulting in

/**
 * A mutable object which accumulates double values and tracks some basic statistics over all the
 * values added so far. The values may be added singly or in groups. This class is not thread safe.
 *
 * @author Pete Gillin
 * @author Kevin Bourrillion
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class StatsAccumulator {
  /** Creates a new accumulator. */
  public StatsAccumulator() {}

 * StatsAccumulator#add} and {@link StatsAccumulator#addAll} methods. For tests of the {@link
 * StatsAccumulator#snapshot} method which returns {@link Stats} instances, see {@link StatsTest}.
 *
 * @author Pete Gillin
 */
@NullUnmarked
public class StatsAccumulatorTest extends TestCase {

  private StatsAccumulator emptyAccumulator;
  private StatsAccumulator emptyAccumulatorByAddAllEmptyIterable;

 * calculate <i>only</i> the mean.
 *
 * <p><b>Java 8+ users:</b> If you are not using any of the variance statistics, you may wish to use
 * built-in JDK libraries instead of this class.
 *
 * @author Pete Gillin
 * @author Kevin Bourrillion
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class Stats implements Serializable {

  private final long count;
  private final double mean;

 * either form}), only the overhead is required. The number of object allocations is independent of
 * N in both cases.
 *
 * @author Pete Gillin
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class Quantiles {
  /**
   * Constructor for a type that is not meant to be instantiated.
   *