roll-reduce

Generic rolling-value reducer interface, e.g. rolling averages, etc.

Install

$ npm install --save roll-reduce

Usage

import Rolling from '../src/index.js'
const rolling = Rolling(3)

rolling.push(1)
rolling.sum() // 1
rolling.average() // 1
rolling.push(2)
rolling.sum() // 3
rolling.average() // 1.5
rolling.push(3)
rolling.sum() // 6
rolling.average() // 2

// once the size is reached, it will calculate a rolling value
rolling.push(4)
rolling.sum() // 9 (i.e. 2 + 3 + 4)
rolling.average() // 3
rolling.push(5)
rolling.sum() // 12
rolling.average() // 4

You can also use a custom reducer:

import Rolling from '../src/index.js'
const sum = (x, y) => x + y
const rolling = Rolling(3, sum)

rolling.push(1)
rolling.reduce() // 1
rolling.push(2)
rolling.reduce() // 3
rolling.push(3)
rolling.reduce() // 6
rolling.push(4)
rolling.reduce() // 9
rolling.push(5)
rolling.reduce() // 12

License

ISC © Raine Revere