# isProbability
> Test if a value is a probability.
A **probability** is defined as a numeric value on the interval `[0,1]`.
## Usage
```javascript
var isProbability = require( '@stdlib/assert/is-probability' );
```
#### isProbability( value )
Tests if a `value` is a probability.
```javascript
var Number = require( '@stdlib/number/ctor' );
var bool = isProbability( 0.5 );
// returns true
bool = isProbability( new Number( 0.5 ) );
// returns true
bool = isProbability( 3.14 );
// returns false
bool = isProbability( -5.0 );
// returns false
bool = isProbability( NaN );
// returns false
bool = isProbability( null );
// returns false
```
#### isProbability.isPrimitive( value )
Tests if a `value` is a primitive probability.
```javascript
var Number = require( '@stdlib/number/ctor' );
var bool = isProbability.isPrimitive( 0.33 );
// returns true
bool = isProbability.isPrimitive( new Number( 0.33 ) );
// returns false
```
#### isProbability.isObject( value )
Tests if a `value` is a `Number` object having a value which is a probability.
```javascript
var Number = require( '@stdlib/number/ctor' );
var bool = isProbability.isObject( 0.11 );
// returns false
bool = isProbability.isObject( new Number( 0.11 ) );
// returns true
```
## Examples
```javascript
var Number = require( '@stdlib/number/ctor' );
var isProbability = require( '@stdlib/assert/is-probability' );
var bool = isProbability( 0.5 );
// returns true
bool = isProbability( new Number( 0.5 ) );
// returns true
bool = isProbability( 0.0 );
// returns true
bool = isProbability( 1.0 );
// returns true
bool = isProbability( 3.14 );
// returns false
bool = isProbability( -5.0 );
// returns false
bool = isProbability( NaN );
// returns false
bool = isProbability( '0.5' );
// returns false
bool = isProbability( null );
// returns false
```