repl.txt (1240B)
1 2 {{alias}}( W[, mean] ) 3 Returns an accumulator function which incrementally computes a moving 4 corrected sample standard deviation. 5 6 The `W` parameter defines the number of values over which to compute the 7 moving corrected sample standard deviation. 8 9 If provided a value, the accumulator function returns an updated moving 10 corrected sample standard deviation. If not provided a value, the 11 accumulator function returns the current moving corrected sample standard 12 deviation. 13 14 As `W` values are needed to fill the window buffer, the first `W-1` returned 15 values are calculated from smaller sample sizes. Until the window is full, 16 each returned value is calculated from all provided values. 17 18 Parameters 19 ---------- 20 W: integer 21 Window size. 22 23 mean: number (optional) 24 Known mean. 25 26 Returns 27 ------- 28 acc: Function 29 Accumulator function. 30 31 Examples 32 -------- 33 > var accumulator = {{alias}}( 3 ); 34 > var s = accumulator() 35 null 36 > s = accumulator( 2.0 ) 37 0.0 38 > s = accumulator( -5.0 ) 39 ~4.95 40 > s = accumulator( 3.0 ) 41 ~4.36 42 > s = accumulator( 5.0 ) 43 ~5.29 44 > s = accumulator() 45 ~5.29 46 47 See Also 48 -------- 49