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

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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@bb29798906e119fcb2af99e94b60407a270c9b32/lib/node_modules/@stdlib/math/base/special/ramp/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@bb29798906e119fcb2af99e94b60407a270c9b32/lib/node_modules/@stdlib/math/base/special/ramp/docs/img/equation_ramp_function_alternative_defn.svg" alt="Ramp function alternative definition.">
<br>
</div>
<!-- </equation> -->
</section>
<!-- /.intro -->
<section class="usage">
## Usage
```javascript
var ramp = require( '@stdlib/math/base/special/ramp' );
```
#### ramp( x )
Evaluates the [ramp function][ramp-function].
```javascript
var v = ramp( 3.14 );
// returns 3.14
v = ramp( -3.14 );
// returns 0.0
v = ramp( NaN );
// returns NaN
```
</section>
<!-- /.usage -->
<section class="examples">
## Examples
<!-- eslint no-undef: "error" -->
```javascript
var linspace = require( '@stdlib/array/linspace' );
var ramp = require( '@stdlib/math/base/special/ramp' );
var x = linspace( -10.0, 10.0, 101 );
var i;
for ( i = 0; i < x.length; i++ ) {
console.log( 'R(%d) = %d', x[ i ], ramp( 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/ramp.h"
```
#### stdlib_base_ramp( x )
Evaluates the ramp function.
```c
double y = stdlib_base_ramp( 3.0 );
// returns 3.0
```
The function accepts the following arguments:
- **x**: `[in] double` input value.
```c
double stdlib_base_ramp( const double 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/ramp.h"
#include <stdio.h>
int main() {
double x[] = { 3.14, -3.14, 0.0, 0.0/0.0 };
double y;
int i;
for ( i = 0; i < 4; i++ ) {
y = stdlib_base_ramp( x[ i ] );
printf( "R(%lf) = %lf\n", x[ i ], y );
}
}
```
</section>
<!-- /.examples -->
</section>
<!-- /.c -->
<section class="links">
[ramp-function]: https://en.wikipedia.org/wiki/Ramp_function
</section>
<!-- /.links -->