https://github.com/stdlib-js/lapack-base-dlacpy
Copy all or part of a matrix A to another matrix B.
https://github.com/stdlib-js/lapack-base-dlacpy
algebra array copy dlacpy double float64 float64array javascript lapack linear math mathematics matrix ndarray node node-js nodejs stdlib subroutines
Last synced: 2 months ago
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Copy all or part of a matrix A to another matrix B.
- Host: GitHub
- URL: https://github.com/stdlib-js/lapack-base-dlacpy
- Owner: stdlib-js
- License: apache-2.0
- Created: 2024-07-28T09:36:50.000Z (over 1 year ago)
- Default Branch: main
- Last Pushed: 2025-06-30T01:21:16.000Z (9 months ago)
- Last Synced: 2025-10-06T13:56:12.529Z (6 months ago)
- Topics: algebra, array, copy, dlacpy, double, float64, float64array, javascript, lapack, linear, math, mathematics, matrix, ndarray, node, node-js, nodejs, stdlib, subroutines
- Language: JavaScript
- Homepage: https://github.com/stdlib-js/stdlib
- Size: 2.69 MB
- Stars: 2
- 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
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README
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# dlacpy
[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url]
> Copy all or part of a matrix `A` to another matrix `B`.
## Installation
```bash
npm install @stdlib/lapack-base-dlacpy
```
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 dlacpy = require( '@stdlib/lapack-base-dlacpy' );
```
#### dlacpy( order, uplo, M, N, A, LDA, B, LDB )
Copies all or part of a matrix `A` to another matrix `B`.
```javascript
var Float64Array = require( '@stdlib/array-float64' );
var A = new Float64Array( [ 1.0, 2.0, 3.0, 4.0 ] );
var B = new Float64Array( 4 );
dlacpy( 'row-major', 'all', 2, 2, A, 2, B, 2 );
// B => [ 1.0, 2.0, 3.0, 4.0 ]
```
The function has the following parameters:
- **order**: storage layout.
- **uplo**: specifies whether to copy the upper or lower triangular/trapezoidal part of a matrix `A`.
- **M**: number of rows in `A`.
- **N**: number of columns in `A`.
- **A**: input [`Float64Array`][mdn-float64array].
- **LDA**: stride of the first dimension of `A` (a.k.a., leading dimension of the matrix `A`).
- **B**: output [`Float64Array`][mdn-float64array].
- **LDB**: stride of the first dimension of `B` (a.k.a., leading dimension of the matrix `B`).
Note that indexing is relative to the first index. To introduce an offset, use [`typed array`][mdn-typed-array] views.
```javascript
var Float64Array = require( '@stdlib/array-float64' );
// Initial arrays...
var A0 = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0 ] );
var B0 = new Float64Array( 5 );
// Create offset views...
var A1 = new Float64Array( A0.buffer, A0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
var B1 = new Float64Array( B0.buffer, B0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
dlacpy( 'row-major', 'all', 2, 2, A1, 2, B1, 2 );
// B0 => [ 0.0, 2.0, 3.0, 4.0, 5.0 ]
```
#### dlacpy.ndarray( uplo, M, N, A, sa1, sa2, oa, B, sb1, sb2, ob )
Copies all or part of a matrix `A` to another matrix `B` using alternative indexing semantics.
```javascript
var Float64Array = require( '@stdlib/array-float64' );
var A = new Float64Array( [ 1.0, 2.0, 3.0, 4.0 ] );
var B = new Float64Array( [ 0.0, 0.0, 0.0, 0.0 ] );
dlacpy.ndarray( 'all', 2, 2, A, 2, 1, 0, B, 2, 1, 0 );
// B => [ 1.0, 2.0, 3.0, 4.0 ]
```
The function has the following parameters:
- **uplo**: specifies whether to copy the upper or lower triangular/trapezoidal part of a matrix `A`.
- **M**: number of rows in `A`.
- **N**: number of columns in `A`.
- **A**: input [`Float64Array`][mdn-float64array].
- **sa1**: stride of the first dimension of `A`.
- **sa2**: stride of the second dimension of `A`.
- **oa**: starting index for `A`.
- **B**: output [`Float64Array`][mdn-float64array].
- **sb1**: stride of the first dimension of `B`.
- **sb2**: stride of the second dimension of `B`.
- **ob**: starting index for `B`.
While [`typed array`][mdn-typed-array] views mandate a view offset based on the underlying buffer, the offset parameters support indexing semantics based on starting indices. For example,
```javascript
var Float64Array = require( '@stdlib/array-float64' );
var A = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0 ] );
var B = new Float64Array( [ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ] );
dlacpy.ndarray( 'all', 2, 2, A, 2, 1, 1, B, 2, 1, 2 );
// B => [ 0.0, 0.0, 2.0, 3.0, 4.0, 5.0 ]
```
## Notes
- `dlacpy()` corresponds to the [LAPACK][lapack] routine [`dlacpy`][lapack-dlacpy].
## Examples
```javascript
var ndarray2array = require( '@stdlib/ndarray-base-to-array' );
var uniform = require( '@stdlib/random-array-discrete-uniform' );
var numel = require( '@stdlib/ndarray-base-numel' );
var shape2strides = require( '@stdlib/ndarray-base-shape2strides' );
var dlacpy = require( '@stdlib/lapack-base-dlacpy' );
var shape = [ 5, 8 ];
var order = 'row-major';
var strides = shape2strides( shape, order );
var N = numel( shape );
var A = uniform( N, -10, 10, {
'dtype': 'float64'
});
console.log( ndarray2array( A, shape, strides, 0, order ) );
var B = uniform( N, -10, 10, {
'dtype': 'float64'
});
console.log( ndarray2array( B, shape, strides, 0, order ) );
dlacpy( order, 'all', shape[ 0 ], shape[ 1 ], A, strides[ 0 ], B, strides[ 0 ] );
console.log( ndarray2array( B, shape, strides, 0, order ) );
```
* * *
## C APIs
### Usage
```c
TODO
```
#### TODO
TODO.
```c
TODO
```
TODO
```c
TODO
```
### Examples
```c
TODO
```
* * *
## 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/lapack-base-dlacpy.svg
[npm-url]: https://npmjs.org/package/@stdlib/lapack-base-dlacpy
[test-image]: https://github.com/stdlib-js/lapack-base-dlacpy/actions/workflows/test.yml/badge.svg?branch=main
[test-url]: https://github.com/stdlib-js/lapack-base-dlacpy/actions/workflows/test.yml?query=branch:main
[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/lapack-base-dlacpy/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/lapack-base-dlacpy?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/lapack-base-dlacpy/tree/deno
[deno-readme]: https://github.com/stdlib-js/lapack-base-dlacpy/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/lapack-base-dlacpy/tree/umd
[umd-readme]: https://github.com/stdlib-js/lapack-base-dlacpy/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/lapack-base-dlacpy/tree/esm
[esm-readme]: https://github.com/stdlib-js/lapack-base-dlacpy/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/lapack-base-dlacpy/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/lapack-base-dlacpy/main/LICENSE
[lapack]: https://www.netlib.org/lapack/explore-html/
[lapack-dlacpy]: https://www.netlib.org/lapack/explore-html/d0/d9e/group__lacpy_gaba7ee02955a93bf8af4a432c98734e65.html#gaba7ee02955a93bf8af4a432c98734e65
[mdn-float64array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float64Array
[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray