npm package: @stdlib/ndarray-base-to-flippedud
Description: Return a new ndarray where the order of elements along the second-to-last dimension of an input ndarray is reversed.
Author: The Stdlib Authors
Latest version: 0.1.1

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# toFlippedud

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> Return a new ndarray where the order of elements along the second-to-last dimension of an input ndarray is reversed.

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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-to-flippedud
```

</section>

<section class="usage">

## Usage

```javascript
var toFlippedud = require( '@stdlib/ndarray-base-to-flippedud' );
```

#### toFlippedud( x )

Returns a new ndarray where the order of elements along the second-to-last dimension of an input ndarray is reversed.

```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 sh = x.shape;
// returns [ 3, 2 ]

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

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

sh = y.shape;
// returns [ 3, 2 ]

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

The function accepts the following arguments:

-   **x**: input ndarray.

</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

-   If provided a zero-dimensional ndarray, as the ndarray has no dimensions to reverse, the function simply returns a copy of the input ndarray. Similarly, if provided a one-dimensional ndarray, as the ndarray has only one dimension, the function simply returns a copy of the input ndarray.

</section>

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<!-- Package usage examples. -->

<section class="examples">

## Examples

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

// Create a linear ndarray buffer:
var buf = zeroTo( 16 );

// Create a three-dimensional ndarray:
var x = array( buf, {
    'shape': [ 2, 4, 2 ]
});

// Reverse the order of second-to-last dimension:
var y = toFlippedud( x );
// returns <ndarray>

var a = ndarray2array( y );
console.log( a );
// => [ [ [ 6, 7 ], [ 4, 5 ], [ 2, 3 ], [ 0, 1 ] ], [ [ 14, 15 ], [ 12, 13 ], [ 10, 11 ], [ 8, 9 ] ] ]
```

</section>

<!-- /.examples -->

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</section>

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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].

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---

## License

See [LICENSE][stdlib-license].


## Copyright

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

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