Shuffly

Shuffly is a JavaScript utility that provides various functions for shuffling arrays. It includes both the Fisher-Yates and Sattolo algorithms for generating unique permutations and for repeated permutations respectively.

Features

• Supports Fisher-Yates & Sattolo algorithms
• Supports Deno via NPM
• Zero dependencies

Installation

To install shuffly, run the following command:

NPM

npm install shuffly

Yarn

yarn add shuffly

pnpm

pnpm add shuffly

Usage

shuffle

import { shuffle } from "shuffly";
// import { shuffle } from "npm:shuffly"; // (for Deno)

const array = [1, 2, 3, 4, 5];
const shuffledArray = shuffle(array);

console.log(shuffledArray); // [1, 3, 5, 2, 4] (shuffled)

The shuffle function is an implementation of the Fisher-Yates shuffle algorithm, which is a widely used algorithm for shuffling elements in an array randomly. The Fisher-Yates shuffle algorithm works by iterating through the array starting from the last element and swapping each element with a randomly chosen element from the remaining unshuffled portion of the array.

Syntax

shuffle<T>(array: T[]): T[]

Time complexity

O(n), where n is the length of the array.

shuffleUnique

import { shuffleUnique } from "shuffly";
// import { shuffleUnique } from "npm:shuffly"; // (for Deno)

const array = [1, 2, 3, 4, 5];
const shuffledArray = shuffleUnique(array);

console.log(shuffledArray); // [2, 4, 1, 5, 3] (shuffled)

The shuffleUnique function is an implementation of the Sattolo algorithm, which is a variant of the Fisher-Yates shuffle algorithm that guarantees that no repeated permutations are generated when shuffling an array. This means that after the shuffling is done, the elements in the array will be in a random order, but that order will be unique and different from all other possible orders of the same elements.

Syntax

shuffleUnique<T>(array: T[]): T[]

Time complexity

O(n), where n is the length of the array.

License

MIT License