54 lines
1.4 KiB
Plaintext
54 lines
1.4 KiB
Plaintext
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{{alias}}( W )
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Returns an accumulator function which incrementally computes a moving
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statistical summary.
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The `W` parameter defines the number of values over which to compute the
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moving statistical summary.
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If provided a value, the accumulator function returns an updated moving
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statistical summary. If not provided a value, the accumulator function
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returns the current moving statistical summary.
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The returned summary is an object containing the following fields:
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- window: window size.
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- sum: sum.
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- mean: arithmetic mean.
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- variance: unbiased sample variance.
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- stdev: corrected sample standard deviation.
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- min: minimum value.
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- max: maximum value.
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- range: range.
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- midrange: arithmetic mean of the minimum and maximum values.
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As `W` values are needed to fill the window buffer, the first `W-1` returned
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summaries are calculated from smaller sample sizes. Until the window is
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full, each returned summary is calculated from all provided values.
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Parameters
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----------
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W: integer
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Window size.
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Returns
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-------
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acc: Function
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Accumulator function.
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Examples
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--------
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> var accumulator = {{alias}}( 3 );
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> var s = accumulator()
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{}
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> s = accumulator( 2.0 )
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{...}
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> s = accumulator( -5.0 )
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{...}
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> s = accumulator()
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{...}
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See Also
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--------
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