time-to-botec/js/node_modules/@stdlib/math/base/assert/is-integer/README.md

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@license Apache-2.0
Copyright (c) 2018 The Stdlib Authors.
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# isInteger
> Test if a finite [double-precision floating-point number][ieee754] is an integer.
<section class="usage">
## 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
```
</section>
<!-- /.usage -->
<section class="notes">
## 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
```
</section>
<!-- /.notes -->
<section class="examples">
## Examples
<!-- eslint no-undef: "error" -->
```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
```
</section>
<!-- /.examples -->
<section class="links">
[ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985
</section>
<!-- /.links -->