npm package: @stdlib/ndarray-base-buffer-dtype
Description: Return the data type of an ndarray data buffer.
Author: The Stdlib Authors
Latest version: 0.4.1

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# Buffer 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 ndarray data buffer.

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<section class="intro">

</section>

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<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-base-buffer-dtype
```

</section>

<section class="usage">

## Usage

```javascript
var dtype = require( '@stdlib/ndarray-base-buffer-dtype' );
```

#### dtype( buffer )

Returns the [data type][@stdlib/ndarray/dtypes] of an ndarray data [buffer][@stdlib/ndarray/base/buffer-ctors].

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

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

If provided an ndarray data [buffer][@stdlib/ndarray/base/buffer-ctors] having an unknown or unsupported [data type][@stdlib/ndarray/dtypes], the function returns `null`.

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

</section>

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</section>

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<section class="examples">

## Examples

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

```javascript
var dtypes = require( '@stdlib/ndarray-dtypes' );
var bufferCtors = require( '@stdlib/ndarray-base-buffer-ctors' );
var dtype = require( '@stdlib/ndarray-base-buffer-dtype' );

// Get a list of supported ndarray buffer data types:
var DTYPES = dtypes( 'integer_and_generic' );

// Buffer length:
var len = 10;

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

// Try an array-like object...
var buf = {
    'length': len
};
dt = dtype( buf );
console.log( '%s == %s => %s', 'generic', dt, dt === 'generic' );
```

</section>

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* * *

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

[@stdlib/ndarray/base/buffer-ctors]: https://www.npmjs.com/package/@stdlib/ndarray-base-buffer-ctors

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