stable

What is stable?

The 'stable' npm package provides stable sorting algorithms. Stable sorting ensures that equal elements retain their relative order after sorting. This is important when sorting by multiple criteria, where the secondary sort should not disturb the order of the primary sort.

What are stable's main functionalities?

stable sorting

This feature allows you to sort an array of objects or values in a stable manner, meaning that the original order of equivalent elements is preserved. The code sample demonstrates sorting an array of objects by the 'age' property.

const stable = require('stable');
const arr = [{name: 'John', age: 45}, {name: 'Jane', age: 45}, {name: 'Joe', age: 30}];
const sortedByAge = stable(arr, (a, b) => a.age - b.age);

in-place stable sorting

This feature provides an in-place stable sort, which means the original array is sorted without creating a copy. The code sample demonstrates sorting an array of numbers in ascending order.

const stable = require('stable');
const arr = [3, 1, 4, 1, 5, 9];
stable.inplace(arr, (a, b) => a - b);

Other packages similar to stable

lodash

Lodash is a utility library that includes a `sortBy` function, which can perform a stable sort when provided with iteratees. It is more feature-rich than 'stable' and includes a wide range of utility functions beyond sorting.

underscore

Underscore.js is another utility library similar to Lodash, offering a `sortBy` function for stable sorting. It is also a general-purpose toolkit with various functions for manipulating collections, arrays, and objects.

README

Stable

A stable array sort, because Array#sort() is not guaranteed stable.

MIT licensed.

From npm

Install with:

npm install stable

Then use it in Node.js or some other CommonJS environment as:

const stable = require('stable')

From the browser

Include stable.js or the minified version stable.min.js in your page, then call stable().

Usage

The default sort is, as with Array#sort, lexicographical:

stable(['foo', 'bar', 'baz'])  // => ['bar', 'baz', 'foo']
stable([10, 1, 5])             // => [1, 10, 5]

Unlike Array#sort, the default sort is NOT in-place. To do an in-place sort, use stable.inplace, which otherwise works the same:

const arr = [10, 1, 5]
stable(arr) === arr          // => false
stable.inplace(arr) === arr  // => true

A comparator function can be specified:

// Regular sort() compatible comparator, that returns a number.
// This demonstrates the default behavior.
const lexCmp = (a, b) => String(a).localeCompare(b)
stable(['foo', 'bar', 'baz'], lexCmp)  // => ['bar', 'baz', 'foo']

// Boolean comparator. Sorts `b` before `a` if true.
// This demonstrates a simple way to sort numerically.
const greaterThan = (a, b) => a > b
stable([10, 1, 5], greaterThan)  // => [1, 5, 10]

License

Copyright (C) 2018 Angry Bytes and contributors.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.