@stdlib/stats/base/dists/uniform/stdev/README.md

Standard library statistical functions.

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# Standard Deviation

> [Uniform][uniform-distribution] distribution [standard deviation][standard-deviation].

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The [standard deviation][standard-deviation] for a [uniform][uniform-distribution] random variable is

<!-- <equation class="equation" label="eq:uniform_stdev" align="center" raw="\sigma = \sqrt{\tfrac{1}{12}} \left( b - a \right)" alt="Standard deviation for a uniform distribution."> -->

<div class="equation" align="center" data-raw-text="\sigma = \sqrt{\tfrac{1}{12}} \left( b - a \right)" data-equation="eq:uniform_stdev">
    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@591cf9d5c3a0cd3c1ceec961e5c49d73a68374cb/lib/node_modules/@stdlib/stats/base/dists/uniform/stdev/docs/img/equation_uniform_stdev.svg" alt="Standard deviation for a uniform distribution.">
    <br>
</div>

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where `a` is the minimum support and `b` the maximum support of the distribution.

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## Usage

```javascript
var stdev = require( '@stdlib/stats/base/dists/uniform/stdev' );
```

#### stdev( a, b )

Returns the [standard deviation][standard-deviation] of a [uniform][uniform-distribution] distribution with parameters `a` (minimum support) and `b` (maximum support).

```javascript
var v = stdev( 0.0, 1.0 );
// returns ~0.289

v = stdev( 4.0, 12.0 );
// returns ~2.309

v = stdev( 2.0, 8.0 );
// returns ~1.732
```

If provided `NaN` as any argument, the function returns `NaN`.

```javascript
var v = stdev( NaN, 2.0 );
// returns NaN

v = stdev( 2.0, NaN );
// returns NaN
```

If provided `a >= b`, the function returns `NaN`.

```javascript
var y = stdev( 3.0, 2.0 );
// returns NaN

y = stdev( 3.0, 3.0 );
// returns NaN
```

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</section>

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## Examples

<!-- eslint no-undef: "error" -->

```javascript
var randu = require( '@stdlib/random/base/randu' );
var stdev = require( '@stdlib/stats/base/dists/uniform/stdev' );

var a;
var b;
var v;
var i;

for ( i = 0; i < 10; i++ ) {
    a = ( randu()*10.0 );
    b = ( randu()*10.0 ) + a;
    v = stdev( a, b );
    console.log( 'a: %d, b: %d, SD(X;a,b): %d', a.toFixed( 4 ), b.toFixed( 4 ), v.toFixed( 4 ) );
}
```

</section>

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</section>

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[uniform-distribution]: https://en.wikipedia.org/wiki/Uniform_distribution_%28continuous%29

[standard-deviation]: https://en.wikipedia.org/wiki/Standard_deviation

</section>

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