@stdlib/array/empty/README.md

Arrays.

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# empty

> Create an uninitialized array having a specified length.

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## Usage

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

#### empty( length\[, dtype] )

Creates an uninitialized array having a specified length.

```javascript
var arr = empty( 2 );
// returns <Float64Array>
```

By default, the output array [data type][@stdlib/array/dtypes] is `float64` (i.e., a [typed array][mdn-typed-array]). To specify an alternative [data type][@stdlib/array/dtypes], provide a `dtype` argument.

```javascript
var arr = empty( 2, 'int32' );
// returns <Int32Array>
```

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## Notes

-   In browser environments, the function always returns zero-filled arrays.
-   If `dtype` is `'generic'`, the function always returns a zero-filled array.
-   In Node.js versions `>=3.0.0`, the underlying memory of returned typed arrays is **not** initialized. Memory contents are unknown and may contain **sensitive** data.

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## Examples

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

```javascript
var dtypes = require( '@stdlib/array/dtypes' );
var empty = require( '@stdlib/array/empty' );

// Get a list of array data types:
var dt = dtypes();

// Generate empty arrays...
var arr;
var i;
for ( i = 0; i < dt.length; i++ ) {
    arr = empty( 4, dt[ i ] );
    console.log( arr );
}
```

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* * *

## See Also

-   <span class="package-name">[`@stdlib/array/empty-like`][@stdlib/array/empty-like]</span><span class="delimiter">: </span><span class="description">create an uninitialized array having the same length and data type as a provided array.</span>
-   <span class="package-name">[`@stdlib/array/full`][@stdlib/array/full]</span><span class="delimiter">: </span><span class="description">create a filled array having a specified length.</span>
-   <span class="package-name">[`@stdlib/array/ones`][@stdlib/array/ones]</span><span class="delimiter">: </span><span class="description">create an array filled with ones and having a specified length.</span>
-   <span class="package-name">[`@stdlib/array/zeros`][@stdlib/array/zeros]</span><span class="delimiter">: </span><span class="description">create a zero-filled array having a specified length.</span>
-   <span class="package-name">[`@stdlib/ndarray/empty`][@stdlib/ndarray/empty]</span><span class="delimiter">: </span><span class="description">create an uninitialized ndarray having a specified shape and data type.</span>

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[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray

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

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[@stdlib/array/empty-like]: https://github.com/stdlib-js/array/tree/main/empty-like

[@stdlib/array/full]: https://github.com/stdlib-js/array/tree/main/full

[@stdlib/array/ones]: https://github.com/stdlib-js/array/tree/main/ones

[@stdlib/array/zeros]: https://github.com/stdlib-js/array/tree/main/zeros

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

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