sincospi

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

Usage

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

sincospi( [out,] 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 ]

By default, the function returns a two-element array containing sin(πx) and cos(πx). To avoid extra memory allocation, the function supports providing an output (destination) object.

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

var out = new Float64Array( 2 );

var v = sincospi( out, 0.0 );
// 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 ] ) );
}
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