# isInteger [![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] > Test if a finite [double-precision floating-point number][ieee754] is an integer.
## Installation ```bash npm install @stdlib/math-base-assert-is-integer ```
## Usage ```javascript var isInteger = require( '@stdlib/math-base-assert-is-integer' ); ``` #### isInteger( x ) Tests if a finite [double-precision floating-point number][ieee754] is an `integer`. ```javascript var bool = isInteger( 1.0 ); // returns true ```
## Notes - The function assumes a **finite** `number`. If provided positive or negative `infinity`, the function will return `true`, when, in fact, the result is undefined. If `x` can be `infinite`, wrap the implementation as follows: ```javascript function check( x ) { return ( x < Infinity && x > -Infinity && isInteger( x ) ); } var bool = check( Infinity ); // returns false bool = check( -Infinity ); // returns false ```
## Examples ```javascript var isInteger = require( '@stdlib/math-base-assert-is-integer' ); var bool = isInteger( -5.0 ); // returns true bool = isInteger( 3.14 ); // returns false bool = isInteger( NaN ); // returns false ```
* * * ## Notice This package is part of [stdlib][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][stdlib], see the main project [repository][stdlib]. #### Community [![Chat][chat-image]][chat-url] --- ## License See [LICENSE][stdlib-license]. ## Copyright Copyright © 2016-2022. The Stdlib [Authors][stdlib-authors].