time-to-botec/js/node_modules/@stdlib/math/base/special/sqrtf/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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# Square Root
> Compute the principal [square root][square-root] of a single-precision floating-point number.
<section class="intro">
The principal [square root][square-root] is defined as
<!-- <equation class="equation" label="eq:principal_square_root" align="center" raw="\sqrt{x^2} = \begin{matrix} x, & \textrm{if}\ x \geq 0\end{matrix}" alt="Principal square root"> -->
<div class="equation" align="center" data-raw-text="\sqrt{x^2} = \begin{matrix} x, &amp; \textrm{if}\ x \geq 0\end{matrix}" data-equation="eq:principal_square_root">
<img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@fd65465ee942bbb6e3856d58268e1ee90d570989/lib/node_modules/@stdlib/math/base/special/sqrtf/docs/img/equation_principal_square_root.svg" alt="Principal square root">
<br>
</div>
<!-- </equation> -->
</section>
<!-- /.intro -->
<section class="usage">
## Usage
```javascript
var sqrtf = require( '@stdlib/math/base/special/sqrtf' );
```
#### sqrtf( x )
Computes the principal [square root][square-root] of a single-precision floating-point number.
```javascript
var v = sqrtf( 4.0 );
// returns 2.0
v = sqrtf( 9.0 );
// returns 3.0
v = sqrtf( 0.0 );
// returns 0.0
v = sqrtf( NaN );
// returns NaN
```
For negative numbers, the principal [square root][square-root] is **not** defined.
```javascript
var v = sqrtf( -4.0 );
// 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 sqrtf = require( '@stdlib/math/base/special/sqrtf' );
var x;
var i;
for ( i = 0; i < 100; i++ ) {
x = round( randu() * 100.0 );
console.log( 'sqrt(%d) = %d', x, sqrtf( 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/sqrtf.h"
```
#### stdlib_base_sqrtf( x )
Computes the principal [square root][square-root] of a single-precision floating-point number.
```c
float y = stdlib_base_sqrtf( 9.0f );
// returns 3.0f
```
The function accepts the following arguments:
- **x**: `[in] float` input value.
```c
float stdlib_base_sqrtf( 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/sqrtf.h"
#include <stdio.h>
int main() {
float x[] = { 3.14f, 9.0f, 0.0f, 0.0f/0.0f };
float y;
int i;
for ( i = 0; i < 4; i++ ) {
y = stdlib_base_sqrtf( x[ i ] );
printf( "sqrt(%f) = %f\n", x[ i ], y );
}
}
```
</section>
<!-- /.examples -->
</section>
<!-- /.c -->
<section class="links">
[square-root]: https://en.wikipedia.org/wiki/Square_root
</section>
<!-- /.links -->