npm package: @stdlib/ndarray-min-dtype
Description: Determine the minimum ndarray data type of the closest kind necessary for storing a provided scalar value.
Author: The Stdlib Authors
Latest version: 0.3.1

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<details>
  <summary>
    About stdlib...
  </summary>
  <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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# Minimum 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] -->

> Determine the minimum ndarray [data type][@stdlib/ndarray/dtypes] of the closest "kind" necessary for storing a provided scalar value.

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-min-dtype
```

</section>

<section class="usage">

## Usage

```javascript
var minDataType = require( '@stdlib/ndarray-min-dtype' );
```

#### minDataType( value )

Returns the minimum ndarray [data type][@stdlib/ndarray/dtypes] of the closest "kind" necessary for storing a provided scalar value.

```javascript
var dt = minDataType( 3.141592653589793 );
// returns 'float32'

dt = minDataType( -3 );
// returns 'int8'

dt = minDataType( 3 );
// returns 'uint8'

dt = minDataType( '3' );
// returns 'generic'
```

</section>

<!-- /.usage -->

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

<section class="notes">

## Notes

-   The function does **not** provide precision guarantees for non-integer-valued numbers. In other words, the function returns the smallest possible floating-point (i.e., inexact) [data type][@stdlib/ndarray/dtypes] for storing numbers having decimals.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var roundn = require( '@stdlib/math-base-special-roundn' );
var randu = require( '@stdlib/random-base-randu' );
var pow = require( '@stdlib/math-base-special-pow' );
var discreteUniform = require( '@stdlib/random-base-discrete-uniform' );
var minDataType = require( '@stdlib/ndarray-min-dtype' );

var dt;
var v;
var i;

// Generate numbers of varying magnitudes and determine the minimum data type for each value...
for ( i = 0; i < 100; i++ ) {
    v = randu() * pow( 2.0, discreteUniform( 0, 40 ) );
    if ( randu() < 0.5 ) {
        v *= -1;
    }
    v = roundn( v, discreteUniform( -1, 0 ) );
    dt = minDataType( v );
    console.log( 'min(%d) => %s', v, dt );
}
```

</section>

<!-- /.examples -->

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<section class="references">

</section>

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<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/ndarray-dtypes`][@stdlib/ndarray/dtypes]</span><span class="delimiter">: </span><span class="description">list of ndarray data types.</span>
-   <span class="package-name">[`@stdlib/ndarray-promotion-rules`][@stdlib/ndarray/promotion-rules]</span><span class="delimiter">: </span><span class="description">return the ndarray data type with the smallest size and closest kind to which ndarray data types can be safely cast.</span>
-   <span class="package-name">[`@stdlib/ndarray-safe-casts`][@stdlib/ndarray/safe-casts]</span><span class="delimiter">: </span><span class="description">return a list of ndarray data types to which a provided ndarray data type can be safely cast.</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].

</section>

<!-- /.stdlib -->

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[npm-url]: https://npmjs.org/package/@stdlib/ndarray-min-dtype

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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/ndarray-min-dtype/tree/deno
[deno-readme]: https://github.com/stdlib-js/ndarray-min-dtype/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/ndarray-min-dtype/tree/umd
[umd-readme]: https://github.com/stdlib-js/ndarray-min-dtype/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/ndarray-min-dtype/tree/esm
[esm-readme]: https://github.com/stdlib-js/ndarray-min-dtype/blob/esm/README.md
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/ndarray-min-dtype/main/LICENSE

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

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

[@stdlib/ndarray/safe-casts]: https://www.npmjs.com/package/@stdlib/ndarray-safe-casts

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</section>

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