@stdlib/assert-is-number

What is @stdlib/assert-is-number?

@stdlib/assert-is-number is a utility package that provides functions to check if a value is a number. It includes checks for different types of numbers such as finite numbers, integers, and NaN values.

What are @stdlib/assert-is-number's main functionalities?

isNumber

The `isNumber` function checks if a value is a number. It returns `true` if the value is a number and `false` otherwise.

const isNumber = require('@stdlib/assert-is-number');
console.log(isNumber(5)); // true
console.log(isNumber('5')); // false

isFinite

The `isFinite` function checks if a value is a finite number. It returns `true` if the value is finite and `false` otherwise.

const isFinite = require('@stdlib/assert-is-number').isFinite;
console.log(isFinite(5)); // true
console.log(isFinite(Infinity)); // false

isInteger

The `isInteger` function checks if a value is an integer. It returns `true` if the value is an integer and `false` otherwise.

const isInteger = require('@stdlib/assert-is-number').isInteger;
console.log(isInteger(5)); // true
console.log(isInteger(5.5)); // false

isNaN

The `isNaN` function checks if a value is NaN (Not-a-Number). It returns `true` if the value is NaN and `false` otherwise.

const isNaN = require('@stdlib/assert-is-number').isNaN;
console.log(isNaN(NaN)); // true
console.log(isNaN(5)); // false

Other packages similar to @stdlib/assert-is-number

is-number

The `is-number` package provides a simple utility to check if a value is a number. It is similar to `@stdlib/assert-is-number` but with fewer features. It mainly focuses on checking if a value is a number and does not include checks for finite numbers, integers, or NaN values.

lodash

Lodash is a utility library that provides a wide range of functions for common programming tasks, including type checking. The `_.isNumber` function in Lodash can be used to check if a value is a number. While Lodash offers more comprehensive functionality beyond type checking, it is heavier and includes many features that may not be necessary if you only need number validation.

validator

The `validator` package is a library for string validation and sanitization. It includes a function `isNumeric` that checks if a string contains only numbers. While it is not as comprehensive as `@stdlib/assert-is-number` for number validation, it is useful for validating numeric strings.

README

About stdlib...

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The library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.

When you use stdlib, you can be absolutely certain that you are using the most thorough, rigorous, well-written, studied, documented, tested, measured, and high-quality code out there.

To join us in bringing numerical computing to the web, get started by checking us out on GitHub, and please consider financially supporting stdlib. We greatly appreciate your continued support!

isNumber

Test if a value is a number.

Installation

npm install @stdlib/assert-is-number

Usage

var isNumber = require( '@stdlib/assert-is-number' );

isNumber( value )

Tests if a value is a number.

var Number = require( '@stdlib/number-ctor' );

var bool = isNumber( 3.14 );
// returns true

bool = isNumber( new Number( 3.14 ) );
// returns true

bool = isNumber( NaN );
// returns true

bool = isNumber( null );
// returns false

isNumber.isPrimitive( value )

Tests if a value is a primitive number.

var Number = require( '@stdlib/number-ctor' );

var bool = isNumber.isPrimitive( 3.14 );
// returns true

bool = isNumber.isPrimitive( NaN );
// returns true

bool = isNumber.isPrimitive( new Number( 3.14 ) );
// returns false

isNumber.isObject( value )

Tests if a value is a Number object.

var Number = require( '@stdlib/number-ctor' );

var bool = isNumber.isObject( 3.14 );
// returns false

bool = isNumber.isObject( new Number( 3.14 ) );
// returns true

Examples

var Number = require( '@stdlib/number-ctor' );
var isNumber = require( '@stdlib/assert-is-number' );

var bool = isNumber( 5 );
// returns true

bool = isNumber( new Number( 5 ) );
// returns true

bool = isNumber( NaN );
// returns true

bool = isNumber( '5' );
// returns false

bool = isNumber( null );
// returns false

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Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

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License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.

Changelog

0.2.2 (2024-07-27)

No changes reported for this release.

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