npm package: @stdlib/ndarray-base-promote-dtypes
Description: Resolve the data type that results from applying promotion rules to a provided list of data types.
Author: The Stdlib Authors
Latest version: 0.1.1

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# promoteDataTypes

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

> Resolve the data type that results from applying [promotion rules][@stdlib/ndarray/promotion-rules] to a provided list of data types.

<!-- 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>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-base-promote-dtypes
```

</section>

<section class="usage">

## Usage

```javascript
var promoteDataTypes = require( '@stdlib/ndarray-base-promote-dtypes' );
```

#### promoteDataTypes( dtypes )

Returns a data type that results from applying [promotion rules][@stdlib/ndarray/promotion-rules] to a provided list of data types.

```javascript
var dt = promoteDataTypes( [ 'float32', 'float64' ] );
// returns 'float64'
```

The function returns `null` if provided data types which cannot be safely cast to a promoted data type.

```javascript
var dt = promoteDataTypes( [ 'binary', 'complex128' ] );
// 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 cartesianProduct = require( '@stdlib/array-base-cartesian-product' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var promoteDataTypes = require( '@stdlib/ndarray-base-promote-dtypes' );

// Get the list of supported data types:
var dt = dtypes();

// Generate data type pairs:
var pairs = cartesianProduct( dt, dt );

// Resolve promoted data types:
logEachMap( '(%s) => %s', pairs, promoteDataTypes );
```

</section>

<!-- /.examples -->

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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

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---

## License

See [LICENSE][stdlib-license].


## Copyright

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

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[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules

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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/ndarray-base-promote-dtypes/main/LICENSE

[@stdlib/ndarray/promotion-rules]: https://www.npmjs.com/package/@stdlib/ndarray-promotion-rules

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