39 lines
		
	
	
		
			905 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			39 lines
		
	
	
		
			905 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| 
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| {{alias}}( α )
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|     Returns an accumulator function which incrementally computes an
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|     exponentially weighted variance, where α is a smoothing factor between 0 and
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|     1.
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| 
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|     If provided a value, the accumulator function returns an updated variance.
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|     If not provided a value, the accumulator function returns the current
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|     variance.
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| 
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|     If provided `NaN` or a value which, when used in computations, results in
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|     `NaN`, the accumulated value is `NaN` for all future invocations.
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| 
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|     Parameters
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|     ----------
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|     α: number
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|         Smoothing factor (value between 0 and 1).
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| 
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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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| 
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|     Examples
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|     --------
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|     > var accumulator = {{alias}}( 0.5 );
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|     > var v = accumulator()
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|     null
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|     > v = accumulator( 2.0 )
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|     0.0
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|     > v = accumulator( -5.0 )
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|     12.25
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|     > v = accumulator()
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|     12.25
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| 
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|     See Also
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|     --------
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| 
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