Skip to content

algorithm: signum #1266

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged

raklaptudirm merged 6 commits into TheAlgorithms:master from SpiderMath:add-signum

Dec 8, 2022

Merged

algorithm: signum #1266

Changes from all commits

Commits

Show all changes

Select commit Hold shift + click to select a range

🧩 Added signum implementaion

SpiderMath Nov 26, 2022

Fix typo in tests

SpiderMath Nov 26, 2022

🕷️ Fix NaN issue in signum

SpiderMath Nov 28, 2022

Formatting issues fix

SpiderMath Nov 28, 2022

Fixed up the signum function

SpiderMath Dec 5, 2022

Removed else from else-ifs

SpiderMath Dec 6, 2022

File filter

Filter by extension

Conversations

Jump to

Jump to file

Failed to load files.

Loading

Diff view

Diff view

25 changes: 25 additions & 0 deletions Maths/Signum.js

Show comments View file Open in desktop

Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,25 @@
	/*
	A program to demonstrate the implementation of the signum function,
	also known as the sign function, in JavaScript.

	The signum function is an odd mathematical function, which returns the
	sign of the provided real number.
	It can return 3 values: 1 for values greater than zero, 0 for zero itself,
	and -1 for values less than zero

	Wikipedia: https://en.wikipedia.org/wiki/Sign_function
	*/

	/**
	* @param {Number} input
	* @returns {-1 \| 0 \| 1 \| NaN} sign of input (and NaN if the input is not a number)
	*/
	function signum (input) {
	if (input === 0) return 0
	if (input > 0) return 1
	if (input < 0) return -1

	return NaN
	}

	export { signum }

19 changes: 19 additions & 0 deletions Maths/test/Signum.test.js

Show comments View file Open in desktop

Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,19 @@
	import { signum } from '../Signum'

	describe('The sign of a number', () => {
	it('Sign of 10', () => {
	expect(signum(10)).toBe(1)
	})

	it('Sign of 0', () => {
	expect(signum(0)).toBe(0)
	})

	it('Sign of -420', () => {
	expect(signum(-420)).toBe(-1)
	})

	it('Sign of NaN', () => {
	expect(signum(NaN)).toBe(NaN)
	})
	})