npm package: @stdlib/math-base-special-kernel-sincos
Description: Simultaneously compute the sine and cosine of an angle measured in radians on the interval [-π/4, π/4].
Author: The Stdlib Authors
Latest version: 0.1.1

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# kernelSincos

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

> Simultaneously compute the [sine][@stdlib/math/base/special/sin] and [cosine][@stdlib/math/base/special/cos] of an angle measured in radians on the interval `[-π/4, π/4]`.

<section class="installation">

## Installation

```bash
npm install @stdlib/math-base-special-kernel-sincos
```

</section>

<section class="usage">

## Usage

```javascript
var kernelSincos = require( '@stdlib/math-base-special-kernel-sincos' );
```

#### kernelSincos( x, y, out, stride, offset )

Simultaneously computes the [sine][@stdlib/math/base/special/sin] and [cosine][@stdlib/math/base/special/cos] of an angle measured in radians on the interval `[-π/4, π/4]`.

```javascript
var v = kernelSincos( 0.0, 0.0, [ 0.0, 0.0 ], 1, 0 );
// returns [ ~0.0, ~1.0 ]

v = kernelSincos( 3.141592653589793/2.0, 0.0, [ 0.0, 0.0 ], 1, 0 );
// returns [ ~1.0, ~0.0 ]

v = kernelSincos( -3.141592653589793/6.0, 0.0, [ 0.0, 0.0 ], 1, 0 );
// returns [ ~-0.5, ~0.866 ]

v = kernelSincos( NaN, 0.0, [ 0.0, 0.0 ], 1, 0 );
// returns [ NaN, NaN ]
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var linspace = require( '@stdlib/array-base-linspace' );
var PI = require( '@stdlib/constants-float64-pi' );
var kernelSincos = require( '@stdlib/math-base-special-kernel-sincos' );

var x = linspace( -PI/4.0, PI/4.0, 100 );

var y;
var i;
for ( i = 0; i < x.length; i++ ) {
    y = kernelSincos( x[ i ], 0.0, [ 0.0, 0.0 ], 1, 0 );
    console.log( 'kernelSincos(%d) = [ %d, %d ]', x[ i ], y[ 0 ], y[ 1 ] );
}
```

</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/kernel_sincos.h"
```

#### stdlib_base_kernel_sincos( x, y, &sine, &cosine )

Simultaneously computes the [sine][@stdlib/math/base/special/sin] and [cosine][@stdlib/math/base/special/cos] of an angle measured in radians on the interval `[-π/4, π/4]`.

```c
double cosine;
double sine;

stdlib_base_kernel_sincos( 0.0, 0.0, &sine, &cosine );
```

The function accepts the following arguments:

-   **x**: `[in] double` input value (in radians, assumed to be bounded by `~pi/4` in magnitude).
-   **y**: `[in] double` tail of `x`.
-   **sine**: `[out] double*` destination for the sine.
-   **cosine**: `[out] double*` destination for the cosine.

```c
void stdlib_base_kernel_sincos( const double x, const double y, double* sine, double* cosine );
```

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

int main( void ) {
    const double x[] = { -0.7853981633974483, -0.6108652381980153, -0.4363323129985824, -0.26179938779914946, -0.08726646259971649, 0.08726646259971649, 0.26179938779914935, 0.43633231299858233, 0.6108652381980153, 0.7853981633974483 };

    double cosine;
    double sine;
    int i;
    for ( i = 0; i < 10; i++ ) {
        stdlib_base_kernel_sincos( x[ i ], 0.0, &sine, &cosine );
        printf( "x: %lf => sine: %lf, cosine: %lf\n", x[ i ], sine, cosine );
    }
}
```

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

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<section class="related">

</section>

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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].

#### Community

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---

## Copyright

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

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

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

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</section>

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