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101 changes: 100 additions & 1 deletion lib/node_modules/@stdlib/math/base/special/heaviside/README.md
Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,7 @@

@license Apache-2.0

Copyright (c) 2018 The Stdlib Authors.
Copyright (c) 2025 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.
Expand Down Expand Up @@ -164,6 +164,105 @@ logEachMap( 'H(%0.4f) = %0.4f', x, heaviside );

<!-- /.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/heaviside.h"
```

#### stdlib_base_heaviside( x )

Evaluate the [Heaviside function][heaviside-function].

```c
double out = stdlib_base_heaviside( 0.0, 0 );
// returns 0.0

out = stdlib_base_heaviside( 3.141592653589793 / 2.0, 0 );
// returns 1.0
```

The function accepts the following arguments:

- **x**: `[in] double` input value.
- **continuity**: `[in] int` input value.

```c
double stdlib_base_heaviside( const double x, int continuity );
```

</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/heaviside.h"
#include <stdio.h>

int main( void ) {
const double x[] = { 0.0, -0.523, 0.785, -1.047, 3.14 };

double y;
int i;
for ( i = 0; i < 5; i++ ) {
y = stdlib_base_heaviside( x[ i ], STDLIB_HEAVISIDE_CONTINUITY_HALF );
printf( "heaviside(%lf, half-maximum) = %lf\n", x[ i ], y );
}

for ( i = 0; i < 5; i++ ) {
y = stdlib_base_heaviside( x[ i ], STDLIB_HEAVISIDE_CONTINUITY_LEFT );
printf( "heaviside(%lf, left-continuous) = %lf\n", x[ i ], y );
}

for ( i = 0; i < 5; i++ ) {
y = stdlib_base_heaviside( x[ i ], STDLIB_HEAVISIDE_CONTINUITY_RIGHT );
printf( "heaviside(%lf, right-continuous) = %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">
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Original file line number Diff line number Diff line change
@@ -0,0 +1,61 @@
/**
* @license Apache-2.0
*
* Copyright (c) 2025 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.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

'use strict';

// MODULES //

var resolve = require( 'path' ).resolve;
var bench = require( '@stdlib/bench' );
var uniform = require( '@stdlib/random/array/uniform' );
var isnan = require( '@stdlib/math/base/assert/is-nan' );
var tryRequire = require( '@stdlib/utils/try-require' );
var pkg = require( './../package.json' ).name;


// VARIABLES //

var heaviside = tryRequire( resolve( __dirname, './../lib/native.js' ) );
var opts = {
'skip': ( heaviside instanceof Error )
};


// MAIN //

bench( pkg+'::native', opts, function benchmark( b ) {
var x;
var y;
var i;

x = uniform( 100, -10.0, 10.0 );

b.tic();
for ( i = 0; i < b.iterations; i++ ) {
y = heaviside( x[ i%x.length ] );
if ( isnan( y ) ) {
b.fail( 'should not return NaN' );
}
}
b.toc();
if ( isnan( y ) ) {
b.fail( 'should not return NaN' );
}
b.pass( 'benchmark finished' );
b.end();
});
Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
#/
# @license Apache-2.0
#
# Copyright (c) 2018 The Stdlib Authors.
# Copyright (c) 2025 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.
Expand Down
Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
/**
* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib Authors.
* Copyright (c) 2025 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.
Expand All @@ -21,9 +21,10 @@
#include <math.h>
#include <time.h>
#include <sys/time.h>
#include "stdlib/math/base/special/heaviside.h"

#define NAME "heaviside"
#define ITERATIONS 1000000
#define ITERATIONS 10000
#define REPEATS 3

/**
Expand Down Expand Up @@ -83,25 +84,12 @@ static double rand_double( void ) {
return (double)r / ( (double)RAND_MAX + 1.0 );
}

/**
* Computes the Heaviside function.
*
* @param x input value
* @return function result
*/
double heaviside( double x ) {
if ( x >= 0.0 ) {
return 1.0;
}
return 0.0;
}

/**
* Runs a benchmark.
*
* @return elapsed time in seconds
*/
static double benchmark( void ) {
static double benchmark( stdlib_heaviside_continuity_t continuity ) {
double elapsed;
double x[ 100 ];
double y;
Expand All @@ -114,7 +102,7 @@ static double benchmark( void ) {

t = tic();
for ( i = 0; i < ITERATIONS; i++ ) {
y = heaviside( x[ i%100 ] );
y = stdlib_base_heaviside( x[ i%100 ], continuity );
if ( y != y ) {
printf( "should not return NaN\n" );
break;
Expand All @@ -140,7 +128,23 @@ int main( void ) {
print_version();
for ( i = 0; i < REPEATS; i++ ) {
printf( "# c::%s\n", NAME );
elapsed = benchmark();
elapsed = benchmark(STDLIB_HEAVISIDE_CONTINUITY_LEFT);
print_results( elapsed );
printf( "ok %d benchmark finished\n", i+1 );
}
print_summary( REPEATS, REPEATS );

for ( i = 0; i < REPEATS; i++ ) {
printf( "# c::%s\n", NAME );
elapsed = benchmark(STDLIB_HEAVISIDE_CONTINUITY_HALF);
print_results( elapsed );
printf( "ok %d benchmark finished\n", i+1 );
}
print_summary( REPEATS, REPEATS );

for ( i = 0; i < REPEATS; i++ ) {
printf( "# c::%s\n", NAME );
elapsed = benchmark(STDLIB_HEAVISIDE_CONTINUITY_RIGHT);
print_results( elapsed );
printf( "ok %d benchmark finished\n", i+1 );
}
Expand Down
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