# atan
> Compute the [arctangent][arctangent] of a number.
## Usage
```javascript
var atan = require( '@stdlib/math/base/special/atan' );
```
#### atan( x )
Computes the [arctangent][arctangent] of a `number`.
```javascript
var v = atan( 0.0 );
// returns ~0.0
v = atan( -3.141592653589793/2.0 );
// returns ~-1.004
v = atan( 3.141592653589793/2.0 );
// returns ~1.004
v = atan( NaN );
// returns NaN
```
## Examples
```javascript
var linspace = require( '@stdlib/array/linspace' );
var atan = require( '@stdlib/math/base/special/atan' );
var x = linspace( -1000.0, 1000.0, 100 );
var i;
for ( i = 0; i < x.length; i++ ) {
console.log( atan( x[ i ] ) );
}
```
[arctangent]: https://en.wikipedia.org/wiki/Inverse_trigonometric_functions