live-moving-average

An ever updating average of the last n values. See Moving Average.

Reuses the values array to prevent GC-thrashing. Does not slow down with an increasing window size:

window size 10, 1 push, 10 get x 49,988,485 ops/sec ±0.28% (93 runs sampled)
window size 1000, 1 push, 1 get x 64,048,288 ops/sec ±0.42% (93 runs sampled)
window size 100, 1 push, 10 get x 49,012,149 ops/sec ±0.40% (95 runs sampled)

Installing

npm install live-moving-average

Usage

const createWindow = require('live-moving-average')

const avg = createWindow(3, 0) // size of 3, fill with 0

// using api fluently
avg
    .push(2)
    .push(3)
    .push(4)
    .get() // 3, because (2 + 3 + 4) / 3

avg.push(5)
avg.push(6)
avg.get() // 5, because (4 + 5 + 6) / 3

avg.push(7)
avg.get() // 6, because (5 + 6 + 7) / 3

API

const w = createWindow(size, fill = 0)

size and fill must be a number.

w.push(val)

val must be a number.
Returns w.

w.get()

Returns the moving average.

Contributing

If you have a question or need support using live-moving-average, please double-check your code and setup first. If you think you have found a bug or want to propose a feature, use the issues page.