npm package: @stdlib/ndarray-copy
Description: Copy an input ndarray to a new ndarray having the same shape and data type.
Author: The Stdlib Authors
Latest version: 0.1.1

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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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# copy

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

> Copy an input [ndarray][@stdlib/ndarray/ctor] to a new [ndarray][@stdlib/ndarray/ctor] having the same shape and [data type][@stdlib/ndarray/dtypes].

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-copy
```

</section>

<section class="usage">

## Usage

```javascript
var copy = require( '@stdlib/ndarray-copy' );
```

#### copy( x\[, options] )

Copies an input [ndarray][@stdlib/ndarray/ctor] to a new [ndarray][@stdlib/ndarray/ctor] having the same shape and [data type][@stdlib/ndarray/dtypes].

```javascript
var getShape = require( '@stdlib/ndarray-shape' );
var zeros = require( '@stdlib/ndarray-zeros' );

var x = zeros( [ 2, 2 ] );
// returns <ndarray>

var y = copy( x );
// returns <ndarray>

var sh = getShape( y );
// returns [ 2, 2 ]
```

The function supports the following `options`:

-   **dtype**: output [ndarray][@stdlib/ndarray/ctor] [data type][@stdlib/ndarray/dtypes]. Overrides the input ndarray's inferred [data type][@stdlib/ndarray/dtypes].
-   **order**: specifies whether the output [ndarray][@stdlib/ndarray/ctor] should be `'row-major'` (C-style) or `'column-major'` (Fortran-style). Overrides the input ndarray's inferred order.
-   **mode**: specifies how to handle indices which exceed array dimensions (see [`ndarray`][@stdlib/ndarray/ctor]). Default: `'throw'`.
-   **submode**: a mode array which specifies for each dimension how to handle subscripts which exceed array dimensions  (see [`ndarray`][@stdlib/ndarray/ctor]). If provided fewer modes than dimensions, the constructor recycles modes using modulo arithmetic. Default: `[ options.mode ]`.

To override either the `dtype` or `order`, specify the corresponding option. For example, to override the inferred [data type][@stdlib/ndarray/dtypes],

```javascript
var getShape = require( '@stdlib/ndarray-shape' );
var getDtype = require( '@stdlib/ndarray-dtype' );
var zeros = require( '@stdlib/ndarray-zeros' );

var x = zeros( [ 2, 2 ] );
// returns <ndarray>

var dt = String( getDtype( x ) );
// returns 'float64'

var y = copy( x, {
    'dtype': 'float32'
});
// returns <ndarray>

var sh = getShape( y );
// returns [ 2, 2 ]

dt = String( getDtype( y ) );
// returns 'float32'
```

</section>

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<!-- 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 performs a full copy in which an ndarray's underlying data is copied to a new underlying data buffer.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var uniform = require( '@stdlib/random-uniform' );
var ndarray2array = require( '@stdlib/ndarray-to-array' );
var copy = require( '@stdlib/ndarray-copy' );

var x = uniform( [ 5, 2 ], -10.0, 10.0, {
    'dtype': 'generic'
});
console.log( ndarray2array( x ) );

var y = copy( x );
console.log( ndarray2array( y ) );
```

</section>

<!-- /.examples -->

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<section class="references">

</section>

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<section class="related">

</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-copy

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

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

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

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</section>

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