npm package: @stdlib/math-base-special-ramp
Description: Evaluate the ramp function.
Author: The Stdlib Authors
Latest version: 0.2.3

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</details>

# Ramp Function

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> 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="installation">

## Installation

```bash
npm install @stdlib/math-base-special-ramp
```

</section>

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

var opts = {
    'dtype': 'float64'
};
var x = uniform( 101, -10.0, 10.0, opts );

logEachMap( 'R(%0.4f) = %0.4f', x, ramp );
```

</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( void ) {
    const 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 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/heaviside`][@stdlib/math/base/special/heaviside]</span><span class="delimiter">: </span><span class="description">evaluate the Heaviside function.</span>

</section>

<!-- /.related -->

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<section class="main-repo" >

* * *

## Notice

This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].

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---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/math-base-special-ramp/main/LICENSE

[ramp-function]: https://en.wikipedia.org/wiki/Ramp_function

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[@stdlib/math/base/special/heaviside]: https://www.npmjs.com/package/@stdlib/math-base-special-heaviside

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</section>

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