Vercosine

Compute the versed cosine.

The versed cosine is defined as

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 ] ) );
}