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  1. JDK
  2. JDK-8006572

DoubleStream.sum() & DoubleSummaryStats implementations that reduce numerical errors

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        The sum() and average() methods of java.util.stream.DoubleStream are prone to numerical error.

        Better implementations are required for sequential and parallel evaluation that reduce numerical error.

        The implementations could, for example, use the Kahan summation algorithm:

          http://en.wikipedia.org/wiki/Kahan_summation_algorithm

        That could be applied for sequential evaluation and for parallel evaluation where the leafs are evaluated sequentially and those sums are then added together up the computation tree.

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            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8030298 DoubleStream.sum() & DoubleSummaryStats implementations that reduce numerical errors

            • P3 - Major loss of function.
            • Resolved
            relates to

            Sub-task - The sub-task of the issue JDK-8024354 Explicitly permit DoubleStream.sum()/average() implementations to use higher precision summation

            • P3 - Major loss of function.
            • Resolved

            Bug - A problem which impairs or prevents the functions of the product. JDK-8030942 Explicitly state floating-point summation requirements on non-finite inputs

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Bug - A problem which impairs or prevents the functions of the product. JDK-8030212 Several api.java.util.stream tests got "NaN" value instead of "Infinity" or "-Infinity"

            • P1 - Blocks development and/or testing work, production could not run.
            • Closed

            Bug - A problem which impairs or prevents the functions of the product. JDK-8214761 Bug in parallel Kahan summation implementation

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Closed

            Enhancement - null JDK-8029372 Improve combination of partial sums/averages in streams API

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Open

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                darcy Joe Darcy
                psandoz Paul Sandoz
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