# Chai Stats

Statistical and additional numerical assertions for the Chai Assertion Library.

## Installation

#### Node.js

Chai spies are available on npm.

```
$ npm install chai-stats
```

#### Browser

Include `chai-stats.js`

after including `chai.js`

.

```
<script src="chai-stats.js"></script>
```

## Plug In

If you are using `chai-stats`

in the browser, there is nothing you need to do. It will detect `chai`

in the global
namespace and automagically get used.

If you are using node, here is a useful bit.

```
var chai = require('chai')
, chaiStats = require('chai-stats');
chai.use(chaiStats);
var should = chai.should()
, expect = chai.expect;
```

## API Reference

#### .almost.equal(expected, [precision])

The same as NumPy’s `assert_almost_equal`

, for scalars.
Assert near equality: `abs(expected-actual) < 0.5 * 10**(-decimal)`

```
expect(3.1415).to.almost.equal(3.14159, 3);
assert.almostEqual(3.1416, 3.14159, 3, 'these numbers are almost equal');
```

#### .deepAlmostEqual(actual, expected, [decimal, message])

The same as NumPy’s `assert_almost_equal`

, for objects whose leaves are all numbers.
Assert near equality: `abs(expected-actual) < 0.5 * 10**(-decimal)`

for every leaf.

```
expect({ pi: 3.1416 }).to.almost.eql({ pi: 3.14159 }, 3);
assert.deepAlmostEqual({ pi: 3.1416 }, { pi: 3.14159 }, 3);
```

#### .sum

Modifies the assertion subject with the sum of an array of number so it can be compared using chai’s core assertions.

```
expect([ 1, 2, 3 ]).to.have.sum.equal(6);
expect([ 1, 2, 3 ]).to.have.sum.above(5);
expect([ 1, 2, 3 ]).to.have.sum.below(7);
```

#### .mean

Modifies the assertion subject with the mean of an array of number so it can be compared using chai’s core assertions.

```
expect([ 1, 2, 3 ]).to.have.mean.equal(2);
expect([ 1, 2, 3 ]).to.have.mean.above(1.5);
expect([ 1, 2, 3 ]).to.have.mean.below(2.5);
```

#### .deviation

Modifies the assertion subject with the standard deviations of an array of number so it can be compared using chai’s core assertions.

```
expect([ 1, 2, 3, 4 ]).to.have.deviation.almost.equal(1.290, 2);
```

## Tests

Tests are written using mocha in the BDD interface.
Node tests can be executed using `make test`

. Browser tests can be seen by opening `test/browser/index.html`

.

## Contributors

```
repo age : 3 months ago
commits : 21
active : 5 days
files : 14
authors :
17 Jake Luer 81.0%
4 josher19 19.0%
```

## License

(The MIT License)

Copyright (c) 2012 Jake Luer jake@alogicalparadox.com

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE