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