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