npm package: @stdlib/array-dtype
Description: Return the data type of an array.
Author: The Stdlib Authors
Latest version: 0.3.1

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<details>
  <summary>
    About stdlib...
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  <p>We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.</p>
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# Data Type

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

> Return the data type of an array.

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</section>

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<section class="installation">

## Installation

```bash
npm install @stdlib/array-dtype
```

</section>

<section class="usage">

## Usage

```javascript
var dtype = require( '@stdlib/array-dtype' );
```

#### dtype( array )

Returns the [data type][@stdlib/array/dtypes] of an `array`.

```javascript
var Float64Array = require( '@stdlib/array-float64' );
var arr = new Float64Array( 10 );

var dt = dtype( arr );
// returns 'float64'
```

If provided an argument having an unknown or unsupported [data type][@stdlib/array/dtypes], the function returns `null`.

```javascript
var dt = dtype( 'beep' );
// returns null
```

</section>

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<section class="notes">

</section>

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<section class="examples">

## Examples

<!-- eslint-disable stdlib/new-cap-error -->

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

```javascript
var dtypes = require( '@stdlib/array-dtypes' );
var ctors = require( '@stdlib/array-ctors' );
var dtype = require( '@stdlib/array-dtype' );

var DTYPES;
var ctor;
var arr;
var len;
var dt;
var i;

// Get a list of supported array data types:
DTYPES = dtypes();

// Array length:
len = 10;

// For each supported data type, create an array and confirm its data type...
for ( i = 0; i < DTYPES.length; i++ ) {
    ctor = ctors( DTYPES[ i ] );
    arr = new ctor( len );
    dt = dtype( arr );
    console.log( '%s == %s => %s', DTYPES[ i ], dt, DTYPES[ i ] === dt );
}
```

</section>

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* * *

## See Also

-   <span class="package-name">[`@stdlib/array-dtypes`][@stdlib/array/dtypes]</span><span class="delimiter">: </span><span class="description">list of array data types.</span>

</section>

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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].

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[npm-image]: http://img.shields.io/npm/v/@stdlib/array-dtype.svg
[npm-url]: https://npmjs.org/package/@stdlib/array-dtype

[test-image]: https://github.com/stdlib-js/array-dtype/actions/workflows/test.yml/badge.svg?branch=v0.3.1
[test-url]: https://github.com/stdlib-js/array-dtype/actions/workflows/test.yml?query=branch:v0.3.1

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/array-dtype/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/array-dtype?branch=main

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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/array-dtype/tree/deno
[deno-readme]: https://github.com/stdlib-js/array-dtype/blob/deno/README.md
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/array-dtype/main/LICENSE

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[@stdlib/array/dtypes]: https://www.npmjs.com/package/@stdlib/array-dtypes

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</section>

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