asec

Compute the inverse (arc) secant of a number.

Usage

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

asec( x )

Computes the inverse (arc) secant of x.

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

v = asec( 2.0 );
// returns ~1.0472

v = asec( NaN );
// returns NaN

The domain of x is restricted to the intervals [-inf, -1] and [1, inf]. For x outside of these intervals, the function returns NaN.

var v = asec( -0.5 );
// returns NaN

v = asec( 0.5 );
// returns NaN

Examples

var linspace = require( '@stdlib/array/base/linspace' );
var asec = require( '@stdlib/math/base/special/asec' );

var x = linspace( 1.0, 10.0, 100 );

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

C APIs

Usage

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

stdlib_base_asec( x )

Computes the inverse (arc) secant of x.

double out = stdlib_base_asec( 2.0 );
// returns ~1.0472

The function accepts the following arguments:

x: [in] double input value.

double stdlib_base_asec( const double x );

Examples

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

int main( void ) {
    const double x[] = { -5.0, -3.89, -2.78, -1.67, -0.56, 0.56, 1.67, 2.78, 3.89, 5.0 };
    
    double v;
    int i;
    for ( i = 0; i < 10; i++ ) {
        v = stdlib_base_asec( x[ i ] );
        printf( "asec(%lf) = %lf\n", x[ i ], v );
    }
}