# sinc
> Compute the [cardinal sine][sinc] of a number.
The normalized [cardinal sine][sinc] function is defined as
for any real number `x`.
## Usage
```javascript
var sinc = require( '@stdlib/math/base/special/sinc' );
```
#### sinc( x )
Computes the normalized [cardinal sine][sinc] of a `number`.
```javascript
var v = sinc( 0.5 );
// returns ~0.637
v = sinc( -1.2 );
// returns ~-0.156
v = sinc( 0.0 );
// returns 1.0
v = sinc( NaN );
// returns NaN
```
## Examples
```javascript
var linspace = require( '@stdlib/array/linspace' );
var sinc = require( '@stdlib/math/base/special/sinc' );
var x = linspace( -5.0, 5.0, 100 );
var i;
for ( i = 0; i < x.length; i++ ) {
console.log( sinc( x[ i ] ) );
}
```
[sinc]: https://en.wikipedia.org/wiki/Sinc_function
