120 lines
2.5 KiB
Markdown
120 lines
2.5 KiB
Markdown
|
<!--
|
||
|
|
||
|
@license Apache-2.0
|
||
|
|
||
|
Copyright (c) 2018 The Stdlib Authors.
|
||
|
|
||
|
Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
you may not use this file except in compliance with the License.
|
||
|
You may obtain a copy of the License at
|
||
|
|
||
|
http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
||
|
Unless required by applicable law or agreed to in writing, software
|
||
|
distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
See the License for the specific language governing permissions and
|
||
|
limitations under the License.
|
||
|
|
||
|
-->
|
||
|
|
||
|
# isNonPositiveInteger
|
||
|
|
||
|
> Test if a finite [double-precision floating-point number][ieee754] is a nonpositive integer.
|
||
|
|
||
|
<section class="usage">
|
||
|
|
||
|
## Usage
|
||
|
|
||
|
```javascript
|
||
|
var isNonPositiveInteger = require( '@stdlib/math/base/assert/is-nonpositive-integer' );
|
||
|
```
|
||
|
|
||
|
#### isNonPositiveInteger( x )
|
||
|
|
||
|
Tests if a finite [double-precision floating-point number][ieee754] is a nonpositive `integer`.
|
||
|
|
||
|
```javascript
|
||
|
var bool = isNonPositiveInteger( -1.0 );
|
||
|
// returns true
|
||
|
|
||
|
bool = isNonPositiveInteger( 0.0 );
|
||
|
// returns true
|
||
|
|
||
|
bool = isNonPositiveInteger( 10.0 );
|
||
|
// returns false
|
||
|
```
|
||
|
|
||
|
</section>
|
||
|
|
||
|
<!-- /.usage -->
|
||
|
|
||
|
<section class="notes">
|
||
|
|
||
|
## Notes
|
||
|
|
||
|
- The function assumes a **finite** `number`. If provided 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 &&
|
||
|
isNonPositiveInteger( x )
|
||
|
);
|
||
|
}
|
||
|
|
||
|
var bool = check( -Infinity );
|
||
|
// returns false
|
||
|
```
|
||
|
|
||
|
- The function does **not** distinguish between positive and negative `zero`.
|
||
|
|
||
|
```javascript
|
||
|
var bool = isNonPositiveInteger( 0.0 );
|
||
|
// returns true
|
||
|
|
||
|
bool = isNonPositiveInteger( -0.0 );
|
||
|
// returns true
|
||
|
```
|
||
|
|
||
|
</section>
|
||
|
|
||
|
<!-- /.notes -->
|
||
|
|
||
|
<section class="examples">
|
||
|
|
||
|
## Examples
|
||
|
|
||
|
<!-- eslint no-undef: "error" -->
|
||
|
|
||
|
```javascript
|
||
|
var isNonPositiveInteger = require( '@stdlib/math/base/assert/is-nonpositive-integer' );
|
||
|
|
||
|
var bool = isNonPositiveInteger( -5.0 );
|
||
|
// returns true
|
||
|
|
||
|
bool = isNonPositiveInteger( 0.0 );
|
||
|
// returns true
|
||
|
|
||
|
bool = isNonPositiveInteger( 1.0 );
|
||
|
// returns false
|
||
|
|
||
|
bool = isNonPositiveInteger( -3.14 );
|
||
|
// returns false
|
||
|
|
||
|
bool = isNonPositiveInteger( NaN );
|
||
|
// returns false
|
||
|
```
|
||
|
|
||
|
</section>
|
||
|
|
||
|
<!-- /.examples -->
|
||
|
|
||
|
<section class="links">
|
||
|
|
||
|
[ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985
|
||
|
|
||
|
</section>
|
||
|
|
||
|
<!-- /.links -->
|