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# Minimum Data Type

> 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>

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## 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>

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## Notes

-   The function does **not** provide precision guarantees for non-integer-valued real 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>

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## 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>

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</section>

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* * *

## 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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[@stdlib/ndarray/dtypes]: https://github.com/stdlib-js/ndarray/tree/main/dtypes

[@stdlib/ndarray/promotion-rules]: https://github.com/stdlib-js/ndarray/tree/main/promotion-rules

[@stdlib/ndarray/safe-casts]: https://github.com/stdlib-js/ndarray/tree/main/safe-casts

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</section>

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