npm package: @stdlib/ndarray-base-shift
Description: Return an array containing a truncated view of an input ndarray and a view of the first element(s) along a specified dimension.
Author: The Stdlib Authors
Latest version: 0.1.1

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# shift

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> Return an array containing a truncated view of an input ndarray and a view of the first element(s) along a specified dimension.

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-base-shift
```

</section>

<section class="usage">

## Usage

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

#### shift( x, dim, writable )

Returns an array containing a truncated view of an input ndarray and a view of the first element(s) along a specified dimension.

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

var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
var shape = [ 3, 2 ];
var strides = [ 2, 1 ];
var offset = 0;

var x = ndarray( 'generic', buffer, shape, strides, offset, 'row-major' );
// returns <ndarray>

var arr = ndarray2array( x );
// returns [ [ 1.0, 2.0 ], [ 3.0, 4.0 ], [ 5.0, 6.0 ] ]

var y = shift( x, 0, false );
// returns [ <ndarray>, <ndarray> ]

arr = ndarray2array( y[ 0 ] );
// returns [ [ 3.0, 4.0 ], [ 5.0, 6.0 ] ]

arr = ndarray2array( y[ 1 ] );
// returns [ [ 1.0, 2.0 ] ]
```

The function accepts the following arguments:

-   **x**: input ndarray. Must have one or more dimensions.
-   **dim**: dimension along which to perform the operation. 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`.
-   **writable**: boolean indicating whether a returned ndarray should be writable.

</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 `writable` parameter **only** applies to ndarray constructors supporting **read-only** instances.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var array = require( '@stdlib/ndarray-array' );
var ndarray2array = require( '@stdlib/ndarray-to-array' );
var zeroTo = require( '@stdlib/array-base-zero-to' );
var shift = require( '@stdlib/ndarray-base-shift' );

// Create a linear ndarray buffer:
var buf = zeroTo( 27 );

// Create an ndarray which is a stack of three 3x3 matrices:
var x = array( buf, {
    'shape': [ 3, 3, 3 ]
});

// Remove the first row from each matrix:
var y = shift( x, 1, false );
// returns [ <ndarray>, <ndarray> ]

console.log( ndarray2array( y[ 0 ] ) );
console.log( ndarray2array( y[ 1 ] ) );
```

</section>

<!-- /.examples -->

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* * *

## 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

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---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

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