Vercosine

Compute the versed cosine.

The versed cosine is defined as

Installation

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

Usage

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

vercos( x )

Computes the versed cosine of a number (in radians).

var v = vercos( 0.0 );
// returns 2.0

v = vercos( 3.141592653589793/2.0 );
// returns 1.0

v = vercos( -3.141592653589793/6.0 );
// returns ~1.8660

Examples

var linspace = require( '@stdlib/array-base-linspace' );
var TWO_PI = require( '@stdlib/constants-float64-two-pi' );
var vercos = require( '@stdlib/math-base-special-vercos' );

var x = linspace( 0.0, TWO_PI, 100 );

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

C APIs

Usage

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

stdlib_base_vercos( x )

Computes the versed cosine of a number (in radians).

double out = stdlib_base_vercos( 0.0 );
// returns 2.0

out = stdlib_base_vercos( 3.141592653589793 / 2.0 );
// returns 1.0

The function accepts the following arguments:

• x: [in] double input value.

double stdlib_base_vercos( const double x );

Examples

#include "stdlib/math/base/special/vercos.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_vercos( x[ i ] );
        printf( "vercos(%lf) = %lf\n", x[ i ], y );
    }
}

See Also

• @stdlib/math-base/special/cos: compute the cosine of a number.
• @stdlib/math-base/special/versin: compute the versed sine.

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.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.