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https://issues.apache.org/jira/browse/STATISTICS-84?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17803603#comment-17803603
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Alex Herbert commented on STATISTICS-84:
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Updated the DoubleStatistics to reuse the high precision sum when creating the
SUM and a moment statistic (MEAN, VARIANCE, SKEWNESS, KURTOSIS):
c9077da40d52581be9246c356f1f0076c82b5d58
> Create the Mean from array input using a summation
> --------------------------------------------------
>
> Key: STATISTICS-84
> URL: https://issues.apache.org/jira/browse/STATISTICS-84
> Project: Commons Statistics
> Issue Type: Improvement
> Components: descriptive
> Reporter: Alex Herbert
> Priority: Trivial
> Attachments: mean_double_4096.png, mean_float_4096-1.png,
> mean_float_4096.png
>
>
> The creation of the Mean from an array uses the rolling mean algorithm. This
> requires a divide for each input value. The algorithm is slow when compared
> to a simple sum of the values and a divide of the sum. The advantage is that
> the algorithm is overflow safe and computes the mean in a single pass (useful
> for streams).
> In the majority of use cases a sum will not overflow. Change the array
> construction to attempt a sum to compute the mean, reverting to the rolling
> mean if this fails.
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