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Hacoversine

Compute the half-value coversed sine.

The half-value coversed sine is defined as

$$\mathop{\mathrm{hacoversin}}(\theta) = \frac{1 - \sin \theta}{2}$$

Installation

npm install @stdlib/math-base-special-hacoversin

Alternatively,

• To load the package in a website via a script tag without installation and bundlers, use the ES Module available on the esm branch (see README).
• If you are using Deno, visit the deno branch (see README for usage intructions).
• For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch (see README).

The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.

To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.

Usage

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

hacoversin( x )

Computes the half-value coversed sine (in radians).

var v = hacoversin( 0.0 );
// returns 0.5

v = hacoversin( 3.141592653589793/2.0 );
// returns 0.0

v = hacoversin( -3.141592653589793/6.0 );
// returns 0.75

Examples

var linspace = require( '@stdlib/array-base-linspace' );
var TWO_PI = require( '@stdlib/constants-float64-two-pi' );
var hacoversin = require( '@stdlib/math-base-special-hacoversin' );

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

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

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C APIs

Usage

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

stdlib_base_hacoversin( x )

Computes the half-value coversed sine (in radians).

double out = stdlib_base_hacoversin( 0.0 );
// returns 0.5

out = stdlib_base_hacoversin( 3.141592653589793 / 2.0 );
// returns 0.0

The function accepts the following arguments:

• x: [in] double input value.

double stdlib_base_hacoversin( const double x );

Examples

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

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See Also

• @stdlib/math-base/special/hacovercos: compute the half-value coversed cosine.
• @stdlib/math-base/special/haversin: compute the half-value versed sine.

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Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

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License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.