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

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@license Apache-2.0
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# Ramp Function
> Evaluate the [ramp function][ramp-function].
<section class="intro">
The [ramp function][ramp-function] is defined as
<!-- <equation class="equation" label="eq:ramp_function" align="center" raw="R(x) = \begin{cases} x & \textrm{if}\ x \geq 0 \\ 0 & \textrm{if}\ x \lt 0\end{cases}" alt="Ramp function."> -->
<div class="equation" align="center" data-raw-text="R(x) = \begin{cases} x &amp; \textrm{if}\ x \geq 0 \\ 0 &amp; \textrm{if}\ x \lt 0\end{cases}" data-equation="eq:ramp_function">
<img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@3aca1e2faee6c79270455562ed28fda2e5e31c4c/lib/node_modules/@stdlib/math/base/special/rampf/docs/img/equation_ramp_function.svg" alt="Ramp function.">
<br>
</div>
<!-- </equation> -->
or, alternatively, in terms of the `max` function
<!-- <equation class="equation" label="eq:ramp_function_alternative_defn" align="center" raw="R(x) = \operatorname{max}( x, 0 )" alt="Ramp function alternative definition."> -->
<div class="equation" align="center" data-raw-text="R(x) = \operatorname{max}( x, 0 )" data-equation="eq:ramp_function_alternative_defn">
<img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@3aca1e2faee6c79270455562ed28fda2e5e31c4c/lib/node_modules/@stdlib/math/base/special/rampf/docs/img/equation_ramp_function_alternative_defn.svg" alt="Ramp function alternative definition.">
<br>
</div>
<!-- </equation> -->
</section>
<!-- /.intro -->
<section class="usage">
## Usage
```javascript
var rampf = require( '@stdlib/math/base/special/rampf' );
```
#### rampf( x )
Evaluates the [ramp function][ramp-function].
```javascript
var v = rampf( 3.14 );
// returns 3.14
v = rampf( -3.14 );
// returns 0.0
v = rampf( NaN );
// returns NaN
```
</section>
<!-- /.usage -->
<section class="examples">
## Examples
<!-- eslint no-undef: "error" -->
```javascript
var linspace = require( '@stdlib/array/linspace' );
var rampf = require( '@stdlib/math/base/special/rampf' );
var x = linspace( -10.0, 10.0, 101 );
var i;
for ( i = 0; i < x.length; i++ ) {
console.log( 'R(%d) = %d', x[ i ], rampf( x[ i ] ) );
}
```
</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/rampf.h"
```
#### stdlib_base_rampf( x )
Evaluates the ramp function (single-precision).
```c
float y = stdlib_base_rampf( 3.0f );
// returns 3.0f
```
The function accepts the following arguments:
- **x**: `[in] float` input value.
```c
float stdlib_base_rampf( 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/rampf.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_rampf( x[ i ] );
printf( "R(%f) = %f\n", x[ i ], y );
}
}
```
</section>
<!-- /.examples -->
</section>
<!-- /.c -->
<section class="links">
[ramp-function]: https://en.wikipedia.org/wiki/Ramp_function
</section>
<!-- /.links -->