npm package: @stdlib/math-base-special-tanh
Description: Compute the hyperbolic tangent of a double-precision floating-point number.
Author: The Stdlib Authors
Latest version: 0.2.4

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# tanh

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> Compute the [hyperbolic tangent][hyperbolic-tangent] of a double-precision floating-point number.

<section class="installation">

## Installation

```bash
npm install @stdlib/math-base-special-tanh
```

</section>

<section class="usage">

## Usage

```javascript
var tanh = require( '@stdlib/math-base-special-tanh' );
```

#### tanh( x )

Computes the [hyperbolic tangent][hyperbolic-tangent] of double-precision floating-point number `x`.

```javascript
var v = tanh( 0.0 );
// returns 0.0

v = tanh( -0.0 );
// returns -0.0

v = tanh( 2.0 );
// returns ~0.964

v = tanh( -2.0 );
// returns ~-0.964

v = tanh( NaN );
// returns NaN
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var uniform = require( '@stdlib/random-array-uniform' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var tanh = require( '@stdlib/math-base-special-tanh' );

var opts = {
    'dtype': 'float64'
};
var x = uniform( 100, -4.0, 4.0, opts );

logEachMap( 'tanh(%0.4f) = %0.4f', x, tanh );
```

</section>

<!-- /.examples -->

<!-- C interface documentation. -->

* * *

<section class="c">

## C APIs

<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->

<section class="intro">

</section>

<!-- /.intro -->

<!-- C usage documentation. -->

<section class="usage">

### Usage

```c
#include "stdlib/math/base/special/tanh.h"
```

#### stdlib_base_tanh( x )

Computes the [hyperbolic tangent][hyperbolic-tangent] of double-precision floating-point number `x`.

```c
double out = stdlib_base_tanh( 2.0 );
// returns ~0.964

out = stdlib_base_tanh( -2.0 );
// returns ~-0.964
```

The function accepts the following arguments:

-   **x**: `[in] double` input value.

```c
double stdlib_base_tanh( const double x );
```

</section>

<!-- /.usage -->

<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

</section>

<!-- /.notes -->

<!-- C API usage examples. -->

<section class="examples">

### Examples

```c
#include "stdlib/math/base/special/tanh.h"
#include <stdio.h>

int main( void ) {
    const double x[] = { -4.0, -3.11, -2.22, -1.33, -0.44, 0.44, 1.33, 2.22, 3.11, 4.0 };

    double v;
    int i;
    for ( i = 0; i < 10; i++ ) {
        v = stdlib_base_tanh( x[ i ] );
        printf( "tanh(%lf) = %lf\n", x[ i ], v );
    }
}
```

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/math-base/special/cosh`][@stdlib/math/base/special/cosh]</span><span class="delimiter">: </span><span class="description">compute the hyperbolic cosine of a double-precision floating-point number.</span>
-   <span class="package-name">[`@stdlib/math-base/special/sinh`][@stdlib/math/base/special/sinh]</span><span class="delimiter">: </span><span class="description">compute the hyperbolic sine of a double-precision floating-point number.</span>
-   <span class="package-name">[`@stdlib/math-base/special/tan`][@stdlib/math/base/special/tan]</span><span class="delimiter">: </span><span class="description">evaluate the tangent of a number.</span>

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->


<section class="main-repo" >

* * *

## Notice

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].

#### Community

[![Chat][chat-image]][chat-url]

---

## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

</section>

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[stdlib]: https://github.com/stdlib-js/stdlib

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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-tanh/tree/deno
[deno-readme]: https://github.com/stdlib-js/math-base-special-tanh/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/math-base-special-tanh/tree/umd
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[esm-url]: https://github.com/stdlib-js/math-base-special-tanh/tree/esm
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[branches-url]: https://github.com/stdlib-js/math-base-special-tanh/blob/main/branches.md

[hyperbolic-tangent]: http://mathworld.wolfram.com/HyperbolicTangent.html

<!-- <related-links> -->

[@stdlib/math/base/special/cosh]: https://www.npmjs.com/package/@stdlib/math-base-special-cosh

[@stdlib/math/base/special/sinh]: https://www.npmjs.com/package/@stdlib/math-base-special-sinh

[@stdlib/math/base/special/tan]: https://www.npmjs.com/package/@stdlib/math-base-special-tan

<!-- </related-links> -->

</section>

<!-- /.links -->