Arccoversine

Compute the inverse coversed sine.

The inverse coversed sine is defined as

Usage

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

acoversin( x )

Computes the inverse coversed sine.

var v = acoversin( 0.0 );
// returns ~1.5708

v = acoversin( 3.141592653589793/2.0 );
// returns ~-0.6075

v = acoversin( 3.141592653589793/6.0 );
// returns ~0.4966

If x < 0, x > 2, or x is NaN, the function returns NaN.

var v = acoversin( -1.0 );
// returns NaN

v = acoversin( 3.14 );
// returns NaN

v = acoversin( NaN );
// returns NaN

Examples

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

var x = linspace( 0.0, 2.0, 100 );

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

C APIs

Usage

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

stdlib_base_acoversin( x )

Computes the inverse coversed sine of a double-precision floating-point number (in radians).

double out = stdlib_base_acoversin( 3.141592653589793/2.0 );
// returns ~-0.6075

The function accepts the following arguments:

x: [in] double input value.

double stdlib_base_acoversin( const double x );

Examples

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