srol

Maintaining a simple dynamic rolling average.

The rolling average is the unweighted mean of the previous i numbers where i is the length or argument of the rolling average.

Install

Install with npm:

$ npm install --save srol

Usage

let srol = require('srol');

To create a rolling average of length n use:

let rollingAverage = new srol(n);

Methods

add

To add a number, or an array of numbers, to the rolling average use:

rollingAverage.add(n);

add will throw a TypeError if n is not a number or an array containing not a number.

average

Getter that returns the average of the last rollingAverage.length numbers.

rollingAverage.average;

Example

Simple example or test of the rolling average.

let rollingAverage = new srol(3);
rollingAverage.add(5);

Since there is only 1 number in the array, the average will be 5.

rollingAverage.add(4);
rollingAverage.add(6);

Now the array is 'full' and the average will be 5, (4+5+6)/3.

rollingAverage.add(7);

The first number, 5, is replaced by a 7 and the average becomes 6.

> rollingAverage.average;
6

Running Tests

Test cover the basic function and requirements of the rolling average.

$ npm install && npm test

Contributing

Pull requests are always welcome.