https://github.com/stdlib-js/utils-map4d
Apply a function to each nested element in a four-dimensional nested array and assign the result to a nested element in a new four-dimensional nested array.
https://github.com/stdlib-js/utils-map4d
apply array call fun func function invoke javascript map matrix nested node node-js nodejs stdlib transform util utilities utility utils
Last synced: 4 months ago
JSON representation
Apply a function to each nested element in a four-dimensional nested array and assign the result to a nested element in a new four-dimensional nested array.
- Host: GitHub
- URL: https://github.com/stdlib-js/utils-map4d
- Owner: stdlib-js
- License: apache-2.0
- Created: 2021-12-31T09:04:02.000Z (about 4 years ago)
- Default Branch: main
- Last Pushed: 2025-03-24T01:24:10.000Z (11 months ago)
- Last Synced: 2025-10-05T13:48:13.543Z (4 months ago)
- Topics: apply, array, call, fun, func, function, invoke, javascript, map, matrix, nested, node, node-js, nodejs, stdlib, transform, util, utilities, utility, utils
- Language: JavaScript
- Homepage: https://github.com/stdlib-js/stdlib
- Size: 896 KB
- Stars: 1
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- Contributing: CONTRIBUTING.md
- License: LICENSE
- Code of conduct: CODE_OF_CONDUCT.md
- Citation: CITATION.cff
- Security: SECURITY.md
Awesome Lists containing this project
README
About stdlib...
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.
The library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.
When you use stdlib, you can be absolutely certain that you are using the most thorough, rigorous, well-written, studied, documented, tested, measured, and high-quality code out there.
To join us in bringing numerical computing to the web, get started by checking us out on GitHub, and please consider financially supporting stdlib. We greatly appreciate your continued support!
# map4d
[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url]
> Apply a function to each nested element in a four-dimensional nested array and assign the result to a nested element in a new four-dimensional nested array.
## Installation
```bash
npm install @stdlib/utils-map4d
```
Alternatively,
- To load the package in a website via a `script` tag without installation and bundlers, use the [ES Module][es-module] available on the [`esm`][esm-url] branch (see [README][esm-readme]).
- If you are using Deno, visit the [`deno`][deno-url] branch (see [README][deno-readme] for usage intructions).
- For use in Observable, or in browser/node environments, use the [Universal Module Definition (UMD)][umd] build available on the [`umd`][umd-url] branch (see [README][umd-readme]).
The [branches.md][branches-url] file summarizes the available branches and displays a diagram illustrating their relationships.
To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.
## Usage
```javascript
var map4d = require( '@stdlib/utils-map4d' );
```
#### map4d( arr, fcn\[, thisArg] )
Applies a function to each nested element in a four-dimensional nested array and assigns the result to a nested element in a new four-dimensional nested array.
```javascript
var naryFunction = require( '@stdlib/utils-nary-function' );
var abs = require( '@stdlib/math-base-special-abs' );
var arr = [
[ [ [ -1, -2, -3 ] ] ],
[ [ [ -4, -5, -6 ] ] ]
];
var out = map4d( arr, naryFunction( abs, 1 ) );
// returns [ [ [ [ 1, 2, 3 ] ] ], [ [ [ 4, 5, 6 ] ] ] ]
```
The applied function is provided the following arguments:
- **value**: array element.
- **indices**: current array element indices.
- **arr**: input array.
To set the `this` context when invoking the input function, provide a `thisArg`.
```javascript
var abs = require( '@stdlib/math-base-special-abs' );
function fcn( v ) {
this.count += 1;
return abs( v );
}
var arr = [
[ [ [ -1, -2, -3 ] ] ],
[ [ [ -4, -5, -6 ] ] ]
];
var ctx = {
'count': 0
};
var out = map4d( arr, fcn, ctx );
// returns [ [ [ [ 1, 2, 3 ] ] ], [ [ [ 4, 5, 6 ] ] ] ]
var cnt = ctx.count;
// returns 6
```
## Examples
```javascript
var filledarrayBy = require( '@stdlib/array-filled-by' );
var discreteUniform = require( '@stdlib/random-base-discrete-uniform' ).factory;
var naryFunction = require( '@stdlib/utils-nary-function' );
var abs2 = require( '@stdlib/math-base-special-abs2' );
var map4d = require( '@stdlib/utils-map4d' );
function fill( n ) {
if ( n > 0 ) {
return array;
}
return values;
function array() {
return filledarrayBy( 2, 'generic', fill( n-1 ) );
}
function values( i ) {
var rand = discreteUniform( -10*(i+1), 10*(i+1) );
return filledarrayBy( 10, 'generic', rand );
}
}
// Create a four-dimensional nested array:
var x = filledarrayBy( 2, 'generic', fill( 2 ) );
// Create an explicit unary function:
var f = naryFunction( abs2, 1 );
// Compute the element-wise squared absolute value...
var y = map4d( x, f );
console.log( 'x:' );
console.log( JSON.stringify( x, null, ' ' ) );
console.log( 'y:' );
console.log( JSON.stringify( y, null, ' ' ) );
```
* * *
## See Also
- [`@stdlib/utils-map`][@stdlib/utils/map]: apply a function to each element in an array and assign the result to an element in an output array.
- [`@stdlib/utils-map2d`][@stdlib/utils/map2d]: apply a function to each nested element in an array of arrays and assign the result to a nested element in a new array of arrays.
- [`@stdlib/utils-map3d`][@stdlib/utils/map3d]: apply a function to each nested element in a three-dimensional nested array and assign the result to a nested element in a new three-dimensional nested array.
- [`@stdlib/utils-map5d`][@stdlib/utils/map5d]: apply a function to each nested element in a five-dimensional nested array and assign the result to a nested element in a new five-dimensional nested array.
* * *
## 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 © 2016-2025. The Stdlib [Authors][stdlib-authors].
[npm-image]: http://img.shields.io/npm/v/@stdlib/utils-map4d.svg
[npm-url]: https://npmjs.org/package/@stdlib/utils-map4d
[test-image]: https://github.com/stdlib-js/utils-map4d/actions/workflows/test.yml/badge.svg?branch=main
[test-url]: https://github.com/stdlib-js/utils-map4d/actions/workflows/test.yml?query=branch:main
[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/utils-map4d/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/utils-map4d?branch=main
[chat-image]: https://img.shields.io/gitter/room/stdlib-js/stdlib.svg
[chat-url]: https://app.gitter.im/#/room/#stdlib-js_stdlib:gitter.im
[stdlib]: https://github.com/stdlib-js/stdlib
[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors
[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/utils-map4d/tree/deno
[deno-readme]: https://github.com/stdlib-js/utils-map4d/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/utils-map4d/tree/umd
[umd-readme]: https://github.com/stdlib-js/utils-map4d/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/utils-map4d/tree/esm
[esm-readme]: https://github.com/stdlib-js/utils-map4d/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/utils-map4d/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/utils-map4d/main/LICENSE
[@stdlib/utils/map]: https://github.com/stdlib-js/utils-map
[@stdlib/utils/map2d]: https://github.com/stdlib-js/utils-map2d
[@stdlib/utils/map3d]: https://github.com/stdlib-js/utils-map3d
[@stdlib/utils/map5d]: https://github.com/stdlib-js/utils-map5d