Compute the hyperbolic arctangent of a double-precision floating-point number.
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> Compute the [hyperbolic arctangent][hyperbolic-arctangent] of a double-precision floating-point number.
``bash`
npm install @stdlib/math-base-special-atanh
`javascript`
var atanh = require( '@stdlib/math-base-special-atanh' );
#### atanh( x )
Computes the [hyperbolic arctangent][hyperbolic-arctangent] of a double-precision floating-point number.
`javascript
var v = atanh( 0.0 );
// returns 0.0
v = atanh( -0.0 );
// returns -0.0
v = atanh( 0.5 );
// returns ~0.549
v = atanh( 0.9 );
// returns ~1.472
v = atanh( 1.0 );
// returns Infinity
v = atanh( -1.0 );
// returns -Infinity
`
The domain of x is restricted to [-1,1]. If |x| > 1, the function returns NaN.
`javascript`
var v = atanh( -3.14 );
// returns NaN
`javascript
var uniform = require( '@stdlib/random-array-uniform' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var atanh = require( '@stdlib/math-base-special-atanh' );
var x = uniform( 100, -1.0, 1.0, {
'dtype': 'float64'
});
logEachMap( 'atanh(%0.4f) = %0.4f', x, atanh );
`
*
`c`
#include "stdlib/math/base/special/atanh.h"
#### stdlib_base_atanh( x )
Computes the [hyperbolic arctangent][hyperbolic-arctangent] of a double-precision floating-point number.
`c
double out = stdlib_base_atanh( 0.0 );
// returns 0.0
out = stdlib_base_atanh( -0.0 );
// returns -0.0
`
The function accepts the following arguments:
- x: [in] double input value.
`c`
double stdlib_base_atanh( const double x );
`c
#include "stdlib/math/base/special/atanh.h"
#include
int main( void ) {
const double x[] = { -1.0, -0.78, -0.56, -0.33, -0.11, 0.11, 0.33, 0.56, 0.78, 1.0 };
double v;
int i;
for ( i = 0; i < 10; i++ ) {
v = stdlib_base_atanh( x[ i ] );
printf( "atanh(%lf) = %lf\n", x[ i ], v );
}
}
`
*
- [@stdlib/math-base/special/acosh][@stdlib/math/base/special/acosh]: compute the hyperbolic arccosine of a double-precision floating-point number.
- [@stdlib/math-base/special/asinh][@stdlib/math/base/special/asinh]: compute the hyperbolic arcsine of a double-precision floating-point number.
- [@stdlib/math-base/special/atan][@stdlib/math/base/special/atan]: compute the arctangent of a double-precision floating-point number.
*
This package is part of [stdlib][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][stdlib], see the main project [repository][stdlib].
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---
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[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/math-base-special-atanh/tree/deno
[deno-readme]: https://github.com/stdlib-js/math-base-special-atanh/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/math-base-special-atanh/tree/umd
[umd-readme]: https://github.com/stdlib-js/math-base-special-atanh/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/math-base-special-atanh/tree/esm
[esm-readme]: https://github.com/stdlib-js/math-base-special-atanh/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/math-base-special-atanh/blob/main/branches.md
[hyperbolic-arctangent]: https://en.wikipedia.org/wiki/Inverse_hyperbolic_function
[@stdlib/math/base/special/acosh]: https://www.npmjs.com/package/@stdlib/math-base-special-acosh
[@stdlib/math/base/special/asinh]: https://www.npmjs.com/package/@stdlib/math-base-special-asinh
[@stdlib/math/base/special/atan]: https://www.npmjs.com/package/@stdlib/math-base-special-atan