acosh

Compute the hyperbolic arccosine of a number.

Usage

var acosh = require( '@stdlib/fastmath/special/acosh' );

acosh( x )

Computes the hyperbolic arccosine of a number (in radians).

var v = acosh( 1.0 );
// returns 0.0

v = acosh( 2.0 );
// returns ~1.317

v = acosh( 0.5 );
// returns NaN

The domain of x is restricted to [1,+infinity). If x < 1, the function will return NaN.

var v = acosh( 0.0 );
// returns NaN

Notes

  • For large x, the function will overflow.

    var v = acosh( 1.0e308 );
    // returns Infinity
    // expected 709.889355822726
    

Examples

var linspace = require( '@stdlib/math/utils/linspace' );
var acosh = require( '@stdlib/fastmath/special/acosh' );

var x = linspace( 1.0, 5.0, 103 );
var i;

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