npm package: @stdlib/number-int32-base-identity
Description: Evaluate the identity function for a signed 32-bit integer.
Author: The Stdlib Authors
Latest version: 0.0.1

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# Identity Function

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

> Evaluate the [identity function][identity-function] of a signed 32-bit integer.

<section class="intro">

The [identity-function][identity-function] is defined as

<!-- <equation class="equation" label="eq:identity_function" align="center" raw="f(x) = x" alt="Identity function"> -->

<div class="equation" align="center" data-raw-text="f(x) = x" data-equation="eq:identity_function">
    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@ad7afa5d7ec1b1596f8a4828153d8c2e87a90161/lib/node_modules/@stdlib/number/int32/base/identity/docs/img/equation_identity_function.svg" alt="Identity function">
    <br>
</div>

<!-- </equation> -->

for all `x`.

</section>

<!-- /.intro -->

<section class="installation">

## Installation

```bash
npm install @stdlib/number-int32-base-identity
```

</section>

<section class="usage">

## Usage

```javascript
var identity = require( '@stdlib/number-int32-base-identity' );
```

#### identity( x )

Evaluates the [identity function][identity-function] for a signed 32-bit integer.

```javascript
var v = identity( 1 );
// returns 1

v = identity( 2 );
// returns 2

v = identity( 0 );
// returns 0

v = identity( 2147483647 );
// returns 2147483647
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var identity = require( '@stdlib/number-int32-base-identity' );

var opts = {
    'dtype': 'int32'
};

// Create an array of random values:
var x = discreteUniform( 100, 0, 50, opts );

// Perform element-wise operation:
logEachMap( 'identity(%d) = %d', x, identity );
```

</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/number/int32/base/identity.h"
```

#### stdlib_base_int32_identity( x )

Evaluates the identity function for a signed 32-bit integer.

```c
#include <stdint.h>

int32_t y = stdlib_base_int32_identity( 2 );
// returns 2
```

The function accepts the following arguments:

-   **x**: `[in] int32_t` input value.

```c
int32_t stdlib_base_int32_identity( const int32_t 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/number/int32/base/identity.h"
#include <stdint.h>
#include <stdio.h>

int main( void ) {
    const int32_t x[] = { 3, 5, 10, 12 };

    int32_t y;
    int i;
    for ( i = 0; i < 4; i++ ) {
        y = stdlib_base_int32_identity( x[ i ] );
        printf( "f(%d) = %d\n", x[ i ], y );
    }
}
```

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

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

<section class="related">

</section>

<!-- /.related -->

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<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]

---

## License

See [LICENSE][stdlib-license].


## Copyright

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

</section>

<!-- /.stdlib -->

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[npm-image]: http://img.shields.io/npm/v/@stdlib/number-int32-base-identity.svg
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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/number-int32-base-identity/tree/deno
[deno-readme]: https://github.com/stdlib-js/number-int32-base-identity/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/number-int32-base-identity/tree/umd
[umd-readme]: https://github.com/stdlib-js/number-int32-base-identity/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/number-int32-base-identity/tree/esm
[esm-readme]: https://github.com/stdlib-js/number-int32-base-identity/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/number-int32-base-identity/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/number-int32-base-identity/main/LICENSE

[identity-function]: https://en.wikipedia.org/wiki/Identity_function

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

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</section>

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