npm package: @stdlib/lapack-base-dlapy2
Description: LAPACK routine to calculate sqrt(x^2 + y^2) in a manner which doesn't cause unnecessary overflow.
Author: The Stdlib Authors
Latest version: 0.1.1

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# dlapy2

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

> LAPACK routine to calculate `sqrt(x^2 + y^2)` in a manner which doesn't cause unnecessary overflow.

<section class="installation">

## Installation

```bash
npm install @stdlib/lapack-base-dlapy2
```

</section>

<section class="usage">

## Usage

```javascript
var dlapy2 = require( '@stdlib/lapack-base-dlapy2' );
```

#### dlapy2( x, y )

Computes `sqrt(x^2 + y^2)` in a manner which doesn't cause unnecessary overflow.

```javascript
var out = dlapy2( 3.0, 4.0 );
// returns 5.0
```

The function has the following parameters:

-   **x**: first input number.
-   **y**: second input number.

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   `dlapy2()` corresponds to the [LAPACK][LAPACK] function [`dlapy2`][lapack-dlapy2].

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var dlapy2 = require( '@stdlib/lapack-base-dlapy2' );

var opts = {
    'dtype': 'float64'
};
var x = discreteUniform( 100, -50, 50, opts );
var y = discreteUniform( 100, -50, 50, opts );

logEachMap( 'dlapy2( %d, %d ) = %0.4f', x, y, dlapy2 );
```

</section>

<!-- /.examples -->

<!-- C interface documentation. -->

* * *

<section class="c">

## C APIs

<!-- 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 -->

<!-- C usage documentation. -->

<section class="usage">

### Usage

```c
TODO
```

#### TODO

TODO.

```c
TODO
```

TODO

```c
TODO
```

</section>

<!-- /.usage -->

<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

</section>

<!-- /.notes -->

<!-- C API usage examples. -->

<section class="examples">

### Examples

```c
TODO
```

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

</section>

<!-- /.related -->

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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>

<!-- /.stdlib -->

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<section class="links">

[npm-image]: http://img.shields.io/npm/v/@stdlib/lapack-base-dlapy2.svg
[npm-url]: https://npmjs.org/package/@stdlib/lapack-base-dlapy2

[test-image]: https://github.com/stdlib-js/lapack-base-dlapy2/actions/workflows/test.yml/badge.svg?branch=v0.1.1
[test-url]: https://github.com/stdlib-js/lapack-base-dlapy2/actions/workflows/test.yml?query=branch:v0.1.1

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/lapack-base-dlapy2/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/lapack-base-dlapy2?branch=main

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[stdlib]: https://github.com/stdlib-js/stdlib

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[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-dlapy2/tree/deno
[deno-readme]: https://github.com/stdlib-js/lapack-base-dlapy2/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/lapack-base-dlapy2/tree/umd
[umd-readme]: https://github.com/stdlib-js/lapack-base-dlapy2/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/lapack-base-dlapy2/tree/esm
[esm-readme]: https://github.com/stdlib-js/lapack-base-dlapy2/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/lapack-base-dlapy2/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/lapack-base-dlapy2/main/LICENSE

[lapack]: https://www.netlib.org/lapack/explore-html/

[lapack-dlapy2]: https://www.netlib.org/lapack/explore-html/d8/d5e/group__lapy2_gab55f5b30b6088a4d6ccd9f073aff1eb7.html

</section>

<!-- /.links -->