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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 with [npm](npmjs.org)
8
9```bash
10npm i is-number --save
11```
12
13## Usage
14
15```js
16var isNumber = require('is-number');
17```
18
19### true
20
21See the [tests](./test.js) for more examples.
22
23```js
24isNumber(5e3) //=> 'true'
25isNumber(0xff) //=> 'true'
26isNumber(-1.1) //=> 'true'
27isNumber(0) //=> 'true'
28isNumber(1) //=> 'true'
29isNumber(1.1) //=> 'true'
30isNumber(10) //=> 'true'
31isNumber(10.10) //=> 'true'
32isNumber(100) //=> 'true'
33isNumber('-1.1') //=> 'true'
34isNumber('0') //=> 'true'
35isNumber('012') //=> 'true'
36isNumber('0xff') //=> 'true'
37isNumber('1') //=> 'true'
38isNumber('1.1') //=> 'true'
39isNumber('10') //=> 'true'
40isNumber('10.10') //=> 'true'
41isNumber('100') //=> 'true'
42isNumber('5e3') //=> 'true'
43isNumber(parseInt('012')) //=> 'true'
44isNumber(parseFloat('012')) //=> 'true'
45```
46
47### False
48
49See the [tests](./test.js) for more examples.
50
51```js
52isNumber('foo') //=> 'false'
53isNumber([1]) //=> 'false'
54isNumber([]) //=> 'false'
55isNumber(function () {}) //=> 'false'
56isNumber(Infinity) //=> 'false'
57isNumber(NaN) //=> 'false'
58isNumber(new Array('abc')) //=> 'false'
59isNumber(new Array(2)) //=> 'false'
60isNumber(new Buffer('abc')) //=> 'false'
61isNumber(null) //=> 'false'
62isNumber(undefined) //=> 'false'
63isNumber({abc: 'abc'}) //=> 'false'
64```
65
66## Other projects
67
68* [even](https://github.com/jonschlinkert/even): Get the even numbered items from an array.
69* [is-primitive](https://github.com/jonschlinkert/is-primitive): Returns `true` if the value is a primitive.
70* [is-even](https://github.com/jonschlinkert/is-even): Return true if the given number is even.
71* [is-odd](https://github.com/jonschlinkert/is-odd): Returns true if the given number is odd.
72* [kind-of](https://github.com/jonschlinkert/kind-of): Get the native type of a value.
73* [odd](https://github.com/jonschlinkert/odd): Get the odd numbered items from an array.
74
75## Contributing
76
77Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](https://github.com/jonschlinkert/is-number/issues)
78
79## Run tests
80
81Install dev dependencies:
82
83```bash
84npm i -d && npm test
85```
86
87## Author
88
89**Jon Schlinkert**
90
91+ [github/jonschlinkert](https://github.com/jonschlinkert)
92+ [twitter/jonschlinkert](http://twitter.com/jonschlinkert)
93
94## License
95
96Copyright (c) 2015 Jon Schlinkert
97Released under the MIT license.
98
99***
100
101_This file was generated by [verb-cli](https://github.com/assemble/verb-cli) on May 02, 2015._