acosd

Compute the arccosine in degrees of a double-precision floating-point number.

Installation

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

Usage

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

acosd( x )

Computes the arccosine (in degrees) of a double-precision floating-point number.

var sqrt = require( '@stdlib/math-base-special-sqrt' );
var v = acosd( 0.0 );
// returns 90.0

v = acosd( 0.5 );
// returns ~60.0

v = acosd( sqrt( 2 ) / 2 );
// returns ~45.0

v = acosd( sqrt( 3 ) / 2 );
// returns ~30.0

v = acosd( NaN );
// returns NaN

The domain of x is restricted to [-1,1]. If |x| > 1, the function returns NaN.

var v = acosd( -3.14 );
// returns NaN

Examples

var uniform = require( '@stdlib/random-array-uniform' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var acosd = require( '@stdlib/math-base-special-acosd' );

var x = uniform( 100, -1.0, 1.0, {
    'dtype': 'float64'
});

logEachMap( 'acosd(%0.4f) = %0.4f', x, acosd );

C APIs

Usage

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

stdlib_base_acosd( x )

Computes the arccosine (in degrees) of a double-precision floating-point number.

double out = stdlib_base_acosd( 0.0 );
// returns 90.0

out = stdlib_base_acosd( 0.5 );
// returns ~60.0

The function accepts the following arguments:

• x: [in] double input value.

double stdlib_base_acosd( const double x );

Examples

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

int main( void ) {
    const double x[] = { 1.0, 1.45, 1.89, 2.33, 2.78, 3.22, 3.66, 4.11, 4.55, 5.0 };

    double v;
    int i;
    for ( i = 0; i < 10; i++ ) {
        v = stdlib_base_acosd( x[ i ] );
        printf( "acosd(%lf) = %lf\n", x[ i ], v );
    }
}

See Also

• @stdlib/math-base/special/acos: compute the arccosine of a double-precision floating-point number.
• @stdlib/math-base/special/acosdf: compute the arccosine (in degrees) of a single-precision floating-point number.
• @stdlib/math-base/special/acosh: compute the hyperbolic arccosine of a double-precision floating-point number.
• @stdlib/math-base/special/asind: compute the arcsine (in degrees) of a double-precision floating-point number.
• @stdlib/math-base/special/atand: compute the arctangent (in degrees) of a double-precision floating-point number.

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 © 2016-2026. The Stdlib Authors.