uniq

What is uniq?

The uniq npm package is primarily used for removing duplicate elements from an array. It provides a straightforward and efficient way to ensure that an array contains only unique values. This can be particularly useful in data processing and manipulation tasks where eliminating duplicates is necessary.

What are uniq's main functionalities?

Removing duplicates from an array

This feature allows you to pass an array to the uniq function, and it returns a new array with all the duplicate values removed. The code sample demonstrates how to use the uniq package to filter out duplicate numbers from an array, resulting in an array of unique numbers.

[...new Set([1, 2, 2, 3, 4, 4, 5])] // Returns [1, 2, 3, 4, 5]

Other packages similar to uniq

lodash.uniq

lodash.uniq is a method from the popular Lodash library that provides similar functionality to uniq. It removes duplicate values from an array. Compared to uniq, lodash.uniq is part of a larger utility library, which might be preferable for projects already using Lodash for other purposes.

underscore

Underscore is another utility library that offers a wide range of functions for working with arrays, objects, and functions. Its _.uniq or _.unique function can be used to achieve the same result as the uniq package. The main difference is that Underscore provides a broader set of utilities, making it a heavier dependency if you only need unique array functionality.

README

uniq

Removes all duplicates from an array in place.

Usage

First install using npm:

npm install uniq

Then use it as follows:

var arr = [1, 1, 2, 2, 3, 5]

require("uniq")(arr)
console.log(arr)

//Prints:
//
//  1,2,3,5
//

require("uniq")(array[, compare, sorted])

Removes all duplicates from a sorted array in place.

• array is the array to remove items from
• compare is an optional comparison function that returns 0 when two items are equal, and something non-zero when they are different. If unspecified, then the default equals will be used.
• sorted if true, then assume array is already sorted

Returns: A reference to array

Time Complexity: O(array.length * log(arra.length)) or O(array.length) if sorted

Why use this instead of underscore.uniq[ue]?

A few reasons:

• This library updates the array in place without making an extra copy (and so it is faster for large arrays)
• It also accepts a custom comparison function so you can remove duplicates from arrays containing object
• It is more modular in the sense that it doesn't come with a bazillion other utility grab bag functions.

Credits

(c) 2013 Mikola Lysenko. MIT License