npm package: @stdlib/ndarray-stride
Description: Return the stride along a specified dimension for a provided ndarray.
Author: The Stdlib Authors
Latest version: 0.2.3

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# stride

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> Return the stride along a specified dimension for a provided [ndarray][@stdlib/ndarray/ctor].

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

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

</section>

<section class="usage">

## Usage

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

#### stride( x, dim )

Returns the stride along a specified dimension for a provided [ndarray][@stdlib/ndarray/ctor].

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

var x = zeros( [ 3, 2, 3 ] );
// returns <ndarray>

var st = stride( x, 0 );
// returns 6
```

The function accepts the following arguments:

-   **x**: input ndarray.
-   **dim**: dimension index. If provided an integer less than zero, the dimension index is resolved relative to the last dimension, with the last dimension corresponding to the value `-1`.

</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

-   A "stride" is the linear distance (i.e., number of elements) between adjacent elements along a specified dimension.
-   This function is intended as a slight performance optimization over [`@stdlib/ndarray-strides`][@stdlib/ndarray/strides] when **only** a single stride is needed. For retrieving multiple strides, use [`@stdlib/ndarray/strides`][@stdlib/ndarray/strides] directly.

</section>

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<!-- Package usage examples. -->

<section class="examples">

## Examples

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

<!-- eslint-disable new-cap -->

```javascript
var zeros = require( '@stdlib/ndarray-zeros' );
var slice = require( '@stdlib/ndarray-slice' );
var E = require( '@stdlib/slice-multi' );
var S = require( '@stdlib/slice-ctor' );
var stride = require( '@stdlib/ndarray-stride' );

// Create an array:
var x = zeros( [ 10, 10, 10, 10 ] );
// returns <ndarray>

// Define some slices:
var slices = [
    // :,:,:,:
    E( null, null, null, null ),

    // 5:10,4,2:4,::-1
    E( S( 5, 10 ), 4, S( 2, 4 ), S( null, null, -1 ) ),

    // :,:,2,:
    E( null, null, 2, null ),

    // 1,2,3,:
    E( 1, 2, 3, null ),

    // 1,3,::2,4::2
    E( 1, 3, S( null, null, 2 ), S( 4, null, 2 ) )
];

// Resolve the stride of the first dimension for each slice...
var s;
var i;
for ( i = 0; i < slices.length; i++ ) {
    s = slice( x, slices[ i ] );
    console.log( '(%s) => %d', s.shape.join( ',' ), stride( s, 0 ) );
}
```

</section>

<!-- /.examples -->

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<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/ndarray-array`][@stdlib/ndarray/array]</span><span class="delimiter">: </span><span class="description">multidimensional arrays.</span>
-   <span class="package-name">[`@stdlib/ndarray-ctor`][@stdlib/ndarray/ctor]</span><span class="delimiter">: </span><span class="description">multidimensional array constructor.</span>
-   <span class="package-name">[`@stdlib/ndarray-offset`][@stdlib/ndarray/offset]</span><span class="delimiter">: </span><span class="description">return the index offset specifying the underlying buffer index of the first iterated ndarray element.</span>
-   <span class="package-name">[`@stdlib/ndarray-order`][@stdlib/ndarray/order]</span><span class="delimiter">: </span><span class="description">return the layout order of a provided ndarray.</span>
-   <span class="package-name">[`@stdlib/ndarray-shape`][@stdlib/ndarray/shape]</span><span class="delimiter">: </span><span class="description">return the shape of a provided ndarray.</span>
-   <span class="package-name">[`@stdlib/ndarray-strides`][@stdlib/ndarray/strides]</span><span class="delimiter">: </span><span class="description">return the strides of a provided ndarray.</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].

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

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

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

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