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1# is-number [![NPM version](https://badge.fury.io/js/is-number.svg)](http://badge.fury.io/js/is-number) [![Build Status](https://travis-ci.org/jonschlinkert/is-number.svg)](https://travis-ci.org/jonschlinkert/is-number)
2
3> Returns true if the value is a number. comprehensive tests.
4
5To understand some of the rationale behind the decisions made in this library (and to learn about some oddities of number evaluation in JavaScript), [see this gist](https://gist.github.com/jonschlinkert/e30c70c713da325d0e81).
6
7## Install
8
9Install with [npm](https://www.npmjs.com/)
10
11```sh
12$ npm i is-number --save
13```
14
15## Usage
16
17```js
18var isNumber = require('is-number');
19```
20
21### true
22
23See the [tests](./test.js) for more examples.
24
25```js
26isNumber(5e3) //=> 'true'
27isNumber(0xff) //=> 'true'
28isNumber(-1.1) //=> 'true'
29isNumber(0) //=> 'true'
30isNumber(1) //=> 'true'
31isNumber(1.1) //=> 'true'
32isNumber(10) //=> 'true'
33isNumber(10.10) //=> 'true'
34isNumber(100) //=> 'true'
35isNumber('-1.1') //=> 'true'
36isNumber('0') //=> 'true'
37isNumber('012') //=> 'true'
38isNumber('0xff') //=> 'true'
39isNumber('1') //=> 'true'
40isNumber('1.1') //=> 'true'
41isNumber('10') //=> 'true'
42isNumber('10.10') //=> 'true'
43isNumber('100') //=> 'true'
44isNumber('5e3') //=> 'true'
45isNumber(parseInt('012')) //=> 'true'
46isNumber(parseFloat('012')) //=> 'true'
47```
48
49### False
50
51See the [tests](./test.js) for more examples.
52
53```js
54isNumber('foo') //=> 'false'
55isNumber([1]) //=> 'false'
56isNumber([]) //=> 'false'
57isNumber(function () {}) //=> 'false'
58isNumber(Infinity) //=> 'false'
59isNumber(NaN) //=> 'false'
60isNumber(new Array('abc')) //=> 'false'
61isNumber(new Array(2)) //=> 'false'
62isNumber(new Buffer('abc')) //=> 'false'
63isNumber(null) //=> 'false'
64isNumber(undefined) //=> 'false'
65isNumber({abc: 'abc'}) //=> 'false'
66```
67
68## Other projects
69
70* [even](https://www.npmjs.com/package/even): Get the even numbered items from an array. | [homepage](https://github.com/jonschlinkert/even)
71* [is-even](https://www.npmjs.com/package/is-even): Return true if the given number is even. | [homepage](https://github.com/jonschlinkert/is-even)
72* [is-odd](https://www.npmjs.com/package/is-odd): Returns true if the given number is odd. | [homepage](https://github.com/jonschlinkert/is-odd)
73* [is-primitive](https://www.npmjs.com/package/is-primitive): Returns `true` if the value is a primitive. | [homepage](https://github.com/jonschlinkert/is-primitive)
74* [kind-of](https://www.npmjs.com/package/kind-of): Get the native type of a value. | [homepage](https://github.com/jonschlinkert/kind-of)
75* [odd](https://www.npmjs.com/package/odd): Get the odd numbered items from an array. | [homepage](https://github.com/jonschlinkert/odd)
76
77## Contributing
78
79Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](https://github.com/jonschlinkert/is-number/issues/new).
80
81## Run tests
82
83Install dev dependencies:
84
85```sh
86$ npm i -d && npm test
87```
88
89## Author
90
91**Jon Schlinkert**
92
93+ [github/jonschlinkert](https://github.com/jonschlinkert)
94+ [twitter/jonschlinkert](http://twitter.com/jonschlinkert)
95
96## License
97
98Copyright © 2015 Jon Schlinkert
99Released under the MIT license.
100
101***
102
103_This file was generated by [verb-cli](https://github.com/assemble/verb-cli) on November 22, 2015._
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