time-to-botec/js/node_modules/@stdlib/math/base/special/absf/README.md

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@license Apache-2.0
Copyright (c) 2020 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.
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# Absolute Value
> Compute the [absolute value][absolute-value] of a single-precision floating-point number.
<section class="intro">
The [absolute value][absolute-value] is defined as
<!-- <equation class="equation" label="eq:absolute_value" align="center" raw="|x| = \begin{cases} x & \textrm{if}\ x \geq 0 \\ -x & \textrm{if}\ x < 0\end{cases}" alt="Absolute value"> -->
<div class="equation" align="center" data-raw-text="|x| = \begin{cases} x &amp; \textrm{if}\ x \geq 0 \\ -x &amp; \textrm{if}\ x &lt; 0\end{cases}" data-equation="eq:absolute_value">
<img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@5b4ee1217697eb737011e0d588fddbb119806753/lib/node_modules/@stdlib/math/base/special/absf/docs/img/equation_absolute_value.svg" alt="Absolute value">
<br>
</div>
<!-- </equation> -->
</section>
<!-- /.intro -->
<section class="usage">
## Usage
```javascript
var absf = require( '@stdlib/math/base/special/absf' );
```
#### absf( x )
Computes the [absolute value][absolute-value] of a single-precision floating-point number.
```javascript
var v = absf( -1.0 );
// returns 1.0
v = absf( 2.0 );
// returns 2.0
v = absf( 0.0 );
// returns 0.0
v = absf( -0.0 );
// returns 0.0
v = absf( NaN );
// returns NaN
```
</section>
<!-- /.usage -->
<section class="examples">
## Examples
<!-- eslint no-undef: "error" -->
```javascript
var randu = require( '@stdlib/random/base/randu' );
var round = require( '@stdlib/math/base/special/round' );
var absf = require( '@stdlib/math/base/special/absf' );
var rand;
var i;
for ( i = 0; i < 100; i++ ) {
rand = round( randu() * 100.0 ) - 50.0;
console.log( 'absf(%d) = %d', rand, absf( rand ) );
}
```
</section>
<!-- /.examples -->
<!-- C interface documentation. -->
* * *
<section class="c">
## C APIs
<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
<section class="intro">
</section>
<!-- /.intro -->
<!-- C usage documentation. -->
<section class="usage">
### Usage
```c
#include "stdlib/math/base/special/absf.h"
```
#### stdlib_base_absf( x )
Computes the squared absolute value of a single-precision floating-point number.
```c
float y = stdlib_base_absf( -5.0f );
// returns 5.0f
```
The function accepts the following arguments:
- **x**: `[in] float` input value.
```c
float stdlib_base_absf( const float x );
```
</section>
<!-- /.usage -->
<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
<section class="notes">
</section>
<!-- /.notes -->
<!-- C API usage examples. -->
<section class="examples">
### Examples
```c
#include "stdlib/math/base/special/absf.h"
#include <stdio.h>
int main() {
float x[] = { 3.14f, -3.14f, 0.0f, 0.0f/0.0f };
float y;
int i;
for ( i = 0; i < 4; i++ ) {
y = stdlib_base_absf( x[ i ] );
printf( "|%f| = %f\n", x[ i ], y );
}
}
```
</section>
<!-- /.examples -->
</section>
<!-- /.c -->
<section class="links">
[absolute-value]: https://en.wikipedia.org/wiki/Absolute_value
</section>
<!-- /.links -->