Haversine
Compute the half-value versed sine.
The half-value versed sine is defined as
Usage
var haversin = require( '@stdlib/math/base/special/haversin' );
haversin( x )
Computes the half-value versed sine (in radians).
var v = haversin( 0.0 );
// returns 0.0
v = haversin( 3.141592653589793/2.0 );
// returns ~0.5
v = haversin( -3.141592653589793/6.0 );
// returns ~0.06699
Examples
var linspace = require( '@stdlib/array/base/linspace' );
var TWO_PI = require( '@stdlib/constants/float64/two-pi' );
var haversin = require( '@stdlib/math/base/special/haversin' );
var x = linspace( 0.0, TWO_PI, 100 );
var i;
for ( i = 0; i < x.length; i++ ) {
console.log( haversin( x[ i ] ) );
}
C APIs
Usage
#include "stdlib/math/base/special/haversin.h"
stdlib_base_haversin( x )
Computes the half-value versed sine (in radians).
double out = stdlib_base_haversin( 0.0 );
// returns 0.0
out = stdlib_base_haversin( 3.141592653589793 / 2.0 );
// returns ~0.5
The function accepts the following arguments:
- x:
[in] double
input value.
double stdlib_base_haversin( const double x );
Examples
#include "stdlib/math/base/special/haversin.h"
#include <stdio.h>
int main( void ) {
const double x[] = { 0.0, 0.523, 0.785, 1.047, 3.14 };
double y;
int i;
for ( i = 0; i < 5; i++ ) {
y = stdlib_base_haversin( x[ i ] );
printf( "haversin(%lf) = %lf\n", x[ i ], y );
}
}