# isNumber
> Test if a value is a number.
## Usage
```javascript
var isNumber = require( '@stdlib/assert/is-number' );
```
#### isNumber( value )
Tests if a `value` is a `number`.
```javascript
var Number = require( '@stdlib/number/ctor' );
var bool = isNumber( 3.14 );
// returns true
bool = isNumber( new Number( 3.14 ) );
// returns true
bool = isNumber( NaN );
// returns true
bool = isNumber( null );
// returns false
```
#### isNumber.isPrimitive( value )
Tests if a `value` is a primitive `number`.
```javascript
var Number = require( '@stdlib/number/ctor' );
var bool = isNumber.isPrimitive( 3.14 );
// returns true
bool = isNumber.isPrimitive( NaN );
// returns true
bool = isNumber.isPrimitive( new Number( 3.14 ) );
// returns false
```
#### isNumber.isObject( value )
Tests if a `value` is a `Number` object.
```javascript
var Number = require( '@stdlib/number/ctor' );
var bool = isNumber.isObject( 3.14 );
// returns false
bool = isNumber.isObject( new Number( 3.14 ) );
// returns true
```
## Examples
```javascript
var Number = require( '@stdlib/number/ctor' );
var isNumber = require( '@stdlib/assert/is-number' );
var bool = isNumber( 5 );
// returns true
bool = isNumber( new Number( 5 ) );
// returns true
bool = isNumber( NaN );
// returns true
bool = isNumber( '5' );
// returns false
bool = isNumber( null );
// returns false
```