https://github.com/kdby-io/range-shuffle

Wide-range integer shuffler
https://github.com/kdby-io/range-shuffle

lcg random range shuffle

Last synced: about 1 month ago
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Wide-range integer shuffler

• Host: GitHub
• URL: https://github.com/kdby-io/range-shuffle
• Owner: kdby-io
• License: mit
• Created: 2017-05-17T22:50:18.000Z (over 7 years ago)
• Default Branch: master
• Last Pushed: 2020-03-29T05:30:22.000Z (over 4 years ago)
• Last Synced: 2024-10-05T08:55:13.472Z (about 1 month ago)
• Topics: lcg, random, range, shuffle
• Language: JavaScript
• Homepage:
• Size: 1 MB
• Stars: 1
• Watchers: 1
• Forks: 0
• Open Issues: 10
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# Range-Shuffle [![Build Status](https://img.shields.io/travis/pueue/range-shuffle.svg?style=flat-square)](https://travis-ci.org/pueue/range-shuffle) [![Version](https://img.shields.io/npm/v/range-shuffle.svg?style=flat-square)](https://www.npmjs.com/package/range-shuffle) [![Download](https://img.shields.io/npm/dt/range-shuffle.svg?style=flat-square)](https://www.npmjs.com/package/range-shuffle) [![Greenkeeper badge](https://badges.greenkeeper.io/pueue/range-shuffle.svg)](https://greenkeeper.io/)

Wide-range integer shuffler.

## Goals

- No array

- Reversible

## Getting Started

### Install

```sh

npm install --save range-shuffle

```

### Usage

```javascript

const Shuffler = require('range-shuffle');

// or

import Shuffler from 'range-shuffle';

const rs = new Shuffler({

  MULTIPLIER: 7, // it must be a prime number

  INCREMENT: 9,

  MODULUS: 10,

});

const array = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];

const shuffled = array.map(int => rs.LCG(int));

// [9, 6, 3, 0, 7, 4, 1, 8, 5, 2]

const reversed = shuffled.map(int => rs.reverseLCG(int));

// [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

```

## Principle

[Linear congruential generator](https://en.wikipedia.org/wiki/Linear_congruential_generator)

## Note

All constants & method arguments can be both `Number` and `String` type.  

If you want to use a large number over `Number.MAX_SAFE_INTEGER`(9007199254740991), use a `String` type input like `.LCG('9999999999999999')`.

## API

### `new Shuffler(constants)`

`constants` is a object that must contain **three constants**:

- `MULTIPLIER`: Must be **a prime number**.

- `INCREMENT`

- `MODULUS`: Range for shuffling. `0 ~ (MODULUS - 1)`

### `.LCG(integer)`

Performs linear congruential generating based on constants.

### `.reverseLCG(integer)`

Restores linear congruential generating based on constants.