# isInteger
> Test if a finite [double-precision floating-point number][ieee754] is an integer.
## Usage
```javascript
var isInteger = require( '@stdlib/math/base/assert/is-integer' );
```
#### isInteger( x )
Tests if a finite [double-precision floating-point number][ieee754] is an `integer`.
```javascript
var bool = isInteger( 1.0 );
// returns true
```
## Notes
- The function assumes a **finite** `number`. If provided positive or negative `infinity`, the function will return `true`, when, in fact, the result is undefined. If `x` can be `infinite`, wrap the implementation as follows:
```javascript
function check( x ) {
return (
x < Infinity &&
x > -Infinity &&
isInteger( x )
);
}
var bool = check( Infinity );
// returns false
bool = check( -Infinity );
// returns false
```
## Examples
```javascript
var isInteger = require( '@stdlib/math/base/assert/is-integer' );
var bool = isInteger( -5.0 );
// returns true
bool = isInteger( 3.14 );
// returns false
bool = isInteger( NaN );
// returns false
```
[ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985