time-to-botec/js/node_modules/@stdlib/math/base/special/invf/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.
You may obtain a copy of the License at
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distributed under the License is distributed on an "AS IS" BASIS,
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# invf
> Compute the [multiplicative inverse][multiplicative-inverse] of a single-precision floating-point number.
<section class="intro">
The [multiplicative inverse][multiplicative-inverse] (or **reciprocal**) is defined as
<!-- <equation class="equation" label="eq:multiplicative_inverse" align="center" raw="y = \frac{1}{x}" alt="Multiplicative inverse"> -->
<div class="equation" align="center" data-raw-text="y = \frac{1}{x}" data-equation="eq:multiplicative_inverse">
<img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@11a2410024c2ba7d3681e2c6d6ee91859fc32a28/lib/node_modules/@stdlib/math/base/special/invf/docs/img/equation_multiplicative_inverse.svg" alt="Multiplicative inverse">
<br>
</div>
<!-- </equation> -->
</section>
<!-- /.intro -->
<section class="usage">
## Usage
```javascript
var invf = require( '@stdlib/math/base/special/invf' );
```
#### invf( x )
Computes the [multiplicative inverse][multiplicative-inverse] of a single-precision floating-point number `x`.
```javascript
var v = invf( -1.0 );
// returns -1.0
v = invf( 2.0 );
// returns 0.5
v = invf( 0.0 );
// returns Infinity
v = invf( -0.0 );
// returns -Infinity
v = invf( 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 invf = require( '@stdlib/math/base/special/invf' );
var x;
var i;
for ( i = 0; i < 100; i++ ) {
x = round( randu()*100.0 ) - 50.0;
console.log( 'invf(%d) = %d', x, invf( x ) );
}
```
</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/invf.h"
```
#### stdlib_base_invf( x )
Computes the multiplicative inverse of a single-precision floating-point number.
```c
float y = stdlib_base_invf( 2.0f );
// returns 0.5f
```
The function accepts the following arguments:
- **x**: `[in] float` input value.
```c
float stdlib_base_inv( 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/invf.h"
#include <stdio.h>
int main() {
float x[] = { 3.0f, 4.0f, 5.0f, 12.0f };
float y;
int i;
for ( i = 0; i < 4; i++ ) {
y = stdlib_base_invf( x[ i ] );
printf( "inv(%f) = %f\n", x[ i ], y );
}
}
```
</section>
<!-- /.examples -->
</section>
<!-- /.c -->
<section class="links">
[multiplicative-inverse]: https://en.wikipedia.org/wiki/Multiplicative_inverse
</section>
<!-- /.links -->