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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 discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var logEachMap = require( '@stdlib/console/log-each-map' );
var sqrtf = require( '@stdlib/math/base/special/sqrtf' );

var opts = {
    'dtype': 'float32'
};
var x = discreteUniform( 100, 0, 100, opts );

logEachMap( 'sqrt(%d) = %0.4f', x, sqrtf );
```

</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( void ) {
    const 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 for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/math/base/special/cbrtf`][@stdlib/math/base/special/cbrtf]</span><span class="delimiter">: </span><span class="description">compute the cube root of a single-precision floating-point number.</span>
-   <span class="package-name">[`@stdlib/math/base/special/rsqrtf`][@stdlib/math/base/special/rsqrtf]</span><span class="delimiter">: </span><span class="description">compute the reciprocal square root of a single-precision floating-point number.</span>
-   <span class="package-name">[`@stdlib/math/base/special/sqrt`][@stdlib/math/base/special/sqrt]</span><span class="delimiter">: </span><span class="description">compute the principal square root of a double-precision floating-point number.</span>

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

[square-root]: https://en.wikipedia.org/wiki/Square_root

<!-- <related-links> -->

[@stdlib/math/base/special/cbrtf]: https://github.com/stdlib-js/math/tree/main/base/special/cbrtf

[@stdlib/math/base/special/rsqrtf]: https://github.com/stdlib-js/math/tree/main/base/special/rsqrtf

[@stdlib/math/base/special/sqrt]: https://github.com/stdlib-js/math/tree/main/base/special/sqrt

<!-- </related-links> -->

</section>

<!-- /.links -->
