java.lang.Object
org.apache.commons.statistics.descriptive.Sum
All Implemented Interfaces:
DoubleConsumer, DoubleSupplier, IntSupplier, LongSupplier, DoubleStatistic, StatisticAccumulator<Sum>, StatisticResult

public final class Sum extends Object implements DoubleStatistic, StatisticAccumulator<Sum>
Returns the sum of the available values.
  • The result is zero if no values are added.
  • The result is NaN if any of the values is NaN.
  • The result is NaN if the values contain positive and negative infinity.
  • The result is non-finite if the values contain infinities of the same sign.

Note: In the event of infinite values of the same sign the result will be non-finite. In this case the returned results may differ (either the same infinity or NaN) based on input order if the sum of the finite-only values can overflow to an opposite signed infinity.

This class is designed to work with (though does not require) streams.

This instance is not thread safe. If multiple threads access an instance of this class concurrently, and at least one of the threads invokes the accept or combine method, it must be synchronized externally.

However, it is safe to use accept and combine as accumulator and combiner functions of Collector on a parallel stream, because the parallel instance of Stream.collect() provides the necessary partitioning, isolation, and merging of results for safe and efficient parallel execution.

Since:
1.1
See Also:
  • Sum
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private final org.apache.commons.numbers.core.Sum
    Sum used to compute the sum.
  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    private
    Sum()
    Create an instance.
    (package private)
    Sum(org.apache.commons.numbers.core.Sum sum)
    Create an instance using the specified sum.
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    accept(double value)
    Updates the state of the statistic to reflect the addition of value.
    combine(Sum other)
    Combines the state of the other statistic into this one.
    static Sum
    Creates an instance.
    double
    Gets the sum of all input values.
    static Sum
    of(double... values)
    Returns an instance populated using the input values.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    Methods inherited from interface java.util.function.DoubleConsumer

    andThen

    Methods inherited from interface org.apache.commons.statistics.descriptive.StatisticResult

    getAsBigInteger, getAsInt, getAsLong
  • Field Details

    • delegate

      private final org.apache.commons.numbers.core.Sum delegate
      Sum used to compute the sum.
  • Constructor Details

    • Sum

      private Sum()
      Create an instance.
    • Sum

      Sum(org.apache.commons.numbers.core.Sum sum)
      Create an instance using the specified sum.
      Parameters:
      sum - Sum.
  • Method Details

    • create

      public static Sum create()
      Creates an instance.

      The initial result is zero.

      Returns:
      Sum instance.
    • of

      public static Sum of(double... values)
      Returns an instance populated using the input values.

      The result is NaN if any of the values is NaN or the sum at any point is a NaN.

      When the input is an empty array, the result is zero.

      Parameters:
      values - Values.
      Returns:
      Sum instance.
    • accept

      public void accept(double value)
      Updates the state of the statistic to reflect the addition of value.
      Specified by:
      accept in interface DoubleConsumer
      Parameters:
      value - Value.
    • getAsDouble

      public double getAsDouble()
      Gets the sum of all input values.

      When no values have been added, the result is zero.

      Specified by:
      getAsDouble in interface DoubleSupplier
      Returns:
      sum of all values.
    • combine

      public Sum combine(Sum other)
      Description copied from interface: StatisticAccumulator
      Combines the state of the other statistic into this one.
      Specified by:
      combine in interface StatisticAccumulator<Sum>
      Parameters:
      other - Another statistic to be combined.
      Returns:
      this instance after combining other.