@stdlib/math-base-special-sincospi NPM

sincospi

$NPM version$ $Build Status$ $Coverage Status$

Simultaneously compute the sine and cosine of a number times π.

Installation

npm install @stdlib/math-base-special-sincospi

Usage

var sincospi = require( '@stdlib/math-base-special-sincospi' );

sincospi( x )

Simultaneously computes the sine and cosine of a number times π more accurately than sincos(pi*x), especially for large x.

var v = sincospi( 0.0 );
// returns [ 0.0, 1.0 ]

v = sincospi( 0.5 );
// returns [ 1.0, 0.0 ]

v = sincospi( 0.1 );
// returns [ ~0.309, ~0.951 ]

v = sincospi( NaN );
// returns [ NaN, NaN ]

sincospi( x, out, stride, offset )

Simultaneously computes the sine and cosine of a number times π more accurately than sincos(pi*x), especially for large x, and assigns results to a provided output array.

var Float64Array = require( '@stdlib/array-float64' );

var out = new Float64Array( 2 );

var v = sincospi.assign( 0.0, out, 1, 0 );
// returns <Float64Array>[ 0.0, 1.0 ]

var bool = ( v === out );
// returns true

Examples

var linspace = require( '@stdlib/array-base-linspace' );
var sincospi = require( '@stdlib/math-base-special-sincospi' );

var x = linspace( 0.0, 2.0, 101 );

var i;
for ( i = 0; i < x.length; i++ ) {
    console.log( sincospi( x[ i ] ) );
}

C APIs

Usage

#include "stdlib/math/base/special/sincospi.h"

stdlib_base_sincospi( x, &sine, &cosine )

Simultaneously computes the sine and cosine of a number times π more accurately than sincos(pi*x), especially for large x.

double cosine;
double sine;

stdlib_base_sincospi( 4.0, &sine, &cosine );

The function accepts the following arguments:

x: [in] double input value.
sine: [out] double* destination for the sine.
cosine: [out] double* destination for the cosine.

void stdlib_base_sincospi( const double x, double *sine, double *cosine );

Examples

#include "stdlib/math/base/special/sincospi.h"
#include <stdio.h>

int main( void ) {
    const double x[] = { 0.0, 1.57, 3.14, 6.28 };

    double cosine;
    double sine;
    int i;
    for ( i = 0; i < 4; i++ ) {
        stdlib_base_sincospi( x[ i ], &sine, &cosine );
        printf( "x: %lf => sine: %lf, cosine: %lf\n", x[ i ], sine, cosine );
    }
}

Notice

This package is part of 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, see the main project repository.