Archavercosine
Compute the inverse half-value versed cosine.
The inverse half-value versed cosine is defined as
Usage
var ahavercos = require( '@stdlib/math/base/special/ahavercos' );
ahavercos( x )
Computes the inverse half-value versed cosine.
var v = ahavercos( 0.0 );
// returns ~3.1416
v = ahavercos( 1.0 );
// returns 0.0
v = ahavercos( 0.5 );
// returns ~1.5708
If x < 0, x > 1, or x is NaN, the function returns NaN.
var v = ahavercos( 1.5 );
// returns NaN
v = ahavercos( -3.14 );
// returns NaN
v = ahavercos( NaN );
// returns NaN
Examples
var linspace = require( '@stdlib/array/base/linspace' );
var ahavercos = require( '@stdlib/math/base/special/ahavercos' );
var x = linspace( 0.0, 1.0, 100 );
var i;
for ( i = 0; i < x.length; i++ ) {
console.log( ahavercos( x[ i ] ) );
}
C APIs
Usage
#include "stdlib/math/base/special/ahavercos.h"
stdlib_base_ahavercos( x )
Computes the inverse half-value versed cosine of a double-precision floating-point number (in radians).
double out = stdlib_base_ahavercos( 0.0 );
// returns ~3.1416
If x < 0, x > 1, or x is NaN, the function returns NaN.
double out = stdlib_base_ahavercos( -3.14 );
// returns NaN
The function accepts the following arguments:
- x:
[in] doubleinput value.
double stdlib_base_ahavercos( const double x );
Examples
#include "stdlib/math/base/special/ahavercos.h"
#include <stdio.h>
int main( void ) {
const double x[] = { -2.0, -1.6, -1.2, -0.8, -0.4, 0.4, 0.8, 1.2, 1.6, 2.0 };
double v;
int i;
for ( i = 0; i < 10; i++ ) {
v = stdlib_base_ahavercos( x[ i ] );
printf( "ahavercos(%lf) = %lf\n", x[ i ], v );
}
}