npm package: @stdlib/ndarray-base-transpose
Description: Transpose a matrix (or a stack of matrices).
Author: The Stdlib Authors
Latest version: 0.2.4

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<details>
  <summary>
    About stdlib...
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  <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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# transpose

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

> Transpose a matrix (or a stack of matrices).

<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->

<section class="intro">

</section>

<!-- /.intro -->

<!-- Package usage documentation. -->

<section class="installation">

## Installation

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

</section>

<section class="usage">

## Usage

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

#### transpose( x )

Transposes a matrix (or a stack of matrices) `x`.

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

var x = array( [ [ 1, 2, 3 ], [ 4, 5, 6 ] ] );
// returns <ndarray>

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

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

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

var bool = ( x.data === y.data );
// returns true

bool = ( x.get( 0, 1 ) === y.get( 1, 0 ) );
// returns true
```

</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

-   The returned ndarray is a **view** of the input ndarray. Accordingly, writing to the original ndarray will **mutate** the returned ndarray and vice versa. While powerful, this can lead to subtle bugs. In general, one should handle the returned ndarray as **read-only**.
-   If provided an ndarray with fewer than two dimensions, the function raises an exception.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

<!-- eslint-disable stdlib/no-redeclare -->

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

```javascript
var Float64Array = require( '@stdlib/array-float64' );
var ndarray = require( '@stdlib/ndarray-ctor' );
var rpad = require( '@stdlib/string-right-pad' );
var transpose = require( '@stdlib/ndarray-base-transpose' );

function print( arr, name ) {
    var str;
    var sh;
    var p;
    var i;
    var j;
    var k;

    sh = arr.shape;
    for ( i = 0; i < sh[0]; i++ ) {
        str = name+'['+i+',:,:] = [ ';
        p = str.length + 1;
        for ( j = 0; j < sh[1]; j++ ) {
            if ( j > 0 ) {
                str += rpad( '\n', p, ' ' );
            }
            for ( k = 0; k < sh[2]; k++ ) {
                str += arr.get( i, j, k );
                if ( k < sh[2]-1 ) {
                    str += ', ';
                }
            }
        }
        console.log( str + ' ]\n' );
    }
}

// Create a data buffer:
var buf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );

// Create a stack of matrices:
var x = new ndarray( 'float64', buf, [ 2, 2, 3 ], [ 0, 3, 1 ], 0, 'row-major' );

// Transpose the stack of matrices:
var y = transpose( x );

// Print the stacks:
console.log( '' );
print( x, 'X' );
console.log( '' );
print( y, 'Y' );
```

</section>

<!-- /.examples -->

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<section class="references">

</section>

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<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/ndarray-ctor`][@stdlib/ndarray/ctor]</span><span class="delimiter">: </span><span class="description">multidimensional array constructor.</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].

</section>

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

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</section>

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