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returned=1 errno=0 peeraddr=140.82.121.5:443 state=error: unexpected eof while reading","robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":false,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["algebra","array","blas","dznrm2","euclidean","euclidean-norm","float64","javascript","level-1","linear","math","mathematics","ndarray","node","node-js","nodejs","norm","stdlib","subroutines","vector"],"created_at":"2024-11-10T19:11:54.201Z","updated_at":"2026-02-28T15:01:06.394Z","avatar_url":"https://github.com/stdlib-js.png","language":"C","funding_links":["https://github.com/sponsors/stdlib-js","https://opencollective.com/stdlib","https://tidelift.com/funding/github/npm/@stdlib/stdlib"],"categories":[],"sub_categories":[],"readme":"\u003c!--\n\n@license Apache-2.0\n\nCopyright (c) 2024 The Stdlib Authors.\n\nLicensed under the Apache License, Version 2.0 (the \"License\");\nyou may not use this file except in compliance with the License.\nYou may obtain a copy of the License at\n\n   http://www.apache.org/licenses/LICENSE-2.0\n\nUnless required by applicable law or agreed to in writing, software\ndistributed under the License is distributed on an \"AS IS\" BASIS,\nWITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\nSee the License for the specific language governing permissions and\nlimitations under the License.\n\n--\u003e\n\n\n\u003cdetails\u003e\n  \u003csummary\u003e\n    About stdlib...\n  \u003c/summary\u003e\n  \u003cp\u003eWe 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.\u003c/p\u003e\n  \u003cp\u003eThe 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.\u003c/p\u003e\n  \u003cp\u003eWhen 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.\u003c/p\u003e\n  \u003cp\u003eTo join us in bringing numerical computing to the web, get started by checking us out on \u003ca href=\"https://github.com/stdlib-js/stdlib\"\u003eGitHub\u003c/a\u003e, and please consider \u003ca href=\"https://opencollective.com/stdlib\"\u003efinancially supporting stdlib\u003c/a\u003e. We greatly appreciate your continued support!\u003c/p\u003e\n\u003c/details\u003e\n\n# dznrm2\n\n[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] \u003c!-- [![dependencies][dependencies-image]][dependencies-url] --\u003e\n\n\u003e Compute the L2-norm of a complex double-precision floating-point vector.\n\n\u003csection class=\"installation\"\u003e\n\n## Installation\n\n```bash\nnpm install @stdlib/blas-base-dznrm2\n```\n\nAlternatively,\n\n-   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]).\n-   If you are using Deno, visit the [`deno`][deno-url] branch (see [README][deno-readme] for usage intructions).\n-   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]).\n\nThe [branches.md][branches-url] file summarizes the available branches and displays a diagram illustrating their relationships.\n\nTo 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.\n\n\u003c/section\u003e\n\n\u003csection class=\"usage\"\u003e\n\n## Usage\n\n```javascript\nvar dznrm2 = require( '@stdlib/blas-base-dznrm2' );\n```\n\n#### dznrm2( N, x, strideX )\n\nComputes the L2-norm of a complex double-precision floating-point vector.\n\n```javascript\nvar Complex128Array = require( '@stdlib/array-complex128' );\n\nvar x = new Complex128Array( [ 0.3, 0.1, 0.5, 0.0, 0.0, 0.5, 0.0, 0.2 ] );\n\nvar norm = dznrm2( 4, x, 1 );\n// returns ~0.8\n```\n\nThe function has the following parameters:\n\n-   **N**: number of indexed elements.\n-   **x**: input [`Complex128Array`][@stdlib/array/complex128].\n-   **strideX**: index increment for `x`.\n\nThe `N` and stride parameters determine which elements in the strided array are accessed at runtime. For example, to traverse every other value,\n\n```javascript\nvar Complex128Array = require( '@stdlib/array-complex128' );\n\nvar x = new Complex128Array( [ -2.0, 1.0, 3.0, -5.0, 4.0, 0.0, -1.0, -3.0 ] );\n\nvar norm = dznrm2( 2, x, 2 );\n// returns ~4.6\n```\n\nNote that indexing is relative to the first index. To introduce an offset, use [`typed array`][mdn-typed-array] views.\n\n```javascript\nvar Complex128Array = require( '@stdlib/array-complex128' );\n\n// Initial array:\nvar x0 = new Complex128Array( [ 1.0, -2.0, 3.0, -4.0, 5.0, -6.0 ] );\n\n// Create an offset view:\nvar x1 = new Complex128Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element\n\n// Compute the L2-norm:\nvar norm = dznrm2( 2, x1, 1 );\n// returns ~9.3\n```\n\n#### dznrm2.ndarray( N, x, strideX, offset )\n\nComputes the L2-norm of a complex double-precision floating-point vector using alternative indexing semantics.\n\n```javascript\nvar Complex128Array = require( '@stdlib/array-complex128' );\n\nvar x = new Complex128Array( [ 0.3, 0.1, 0.5, 0.0, 0.0, 0.5, 0.0, 0.2 ] );\n\nvar norm = dznrm2.ndarray( 4, x, 1, 0 );\n// returns ~0.8\n```\n\nThe function has the following additional parameters:\n\n-   **offsetX**: starting index.\n\nWhile [`typed array`][mdn-typed-array] views mandate a view offset based on the underlying buffer, the `offset` parameter supports indexing semantics based on a starting index. For example, to start from the second index,\n\n```javascript\nvar Complex128Array = require( '@stdlib/array-complex128' );\n\nvar x = new Complex128Array( [ 1.0, -2.0, 3.0, -4.0, 5.0, -6.0 ] );\n\nvar norm = dznrm2.ndarray( 2, x, 1, 1 );\n// returns ~9.3\n```\n\n\u003c/section\u003e\n\n\u003c!-- /.usage --\u003e\n\n\u003csection class=\"notes\"\u003e\n\n## Notes\n\n-   If `N \u003c= 0`, both functions return `0.0`.\n-   `dznrm2()` corresponds to the [BLAS][blas] level 1 function [`dznrm2`][dznrm2].\n\n\u003c/section\u003e\n\n\u003c!-- /.notes --\u003e\n\n\u003csection class=\"examples\"\u003e\n\n## Examples\n\n\u003c!-- eslint no-undef: \"error\" --\u003e\n\n```javascript\nvar discreteUniform = require( '@stdlib/random-base-discrete-uniform' );\nvar filledarrayBy = require( '@stdlib/array-filled-by' );\nvar Complex128 = require( '@stdlib/complex-float64-ctor' );\nvar dznrm2 = require( '@stdlib/blas-base-dznrm2' );\n\nfunction rand() {\n    return new Complex128( discreteUniform( 0, 10 ), discreteUniform( -5, 5 ) );\n}\n\nvar x = filledarrayBy( 10, 'complex128', rand );\nconsole.log( x.toString() );\n\n// Computes the L2-norm:\nvar norm = dznrm2( x.length, x, 1 );\nconsole.log( norm );\n```\n\n\u003c/section\u003e\n\n\u003c!-- /.examples --\u003e\n\n\u003c!-- C interface documentation. --\u003e\n\n* * *\n\n\u003csection class=\"c\"\u003e\n\n## C APIs\n\n\u003c!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. --\u003e\n\n\u003csection class=\"intro\"\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.intro --\u003e\n\n\u003c!-- C usage documentation. --\u003e\n\n\u003csection class=\"usage\"\u003e\n\n### Usage\n\n```c\n#include \"stdlib/blas/base/dznrm2.h\"\n```\n\n#### c_dznrm2( N, \\*X, strideX )\n\nComputes the L2-norm of a complex double-precision floating-point vector.\n\n```c\nconst double X[] = { 0.3, 0.1, 0.5, 0.0, 0.0, 0.5, 0.0, 0.2 };\n\ndouble norm = c_dznrm2( 4, (void *)X, 1 );\n// returns 0.8\n```\n\nThe function accepts the following arguments:\n\n-   **N**: `[in] CBLAS_INT` number of indexed elements.\n-   **X**: `[in] void*` input array.\n-   **strideX**: `[in] CBLAS_INT` index increment for `X`.\n\n```c\ndouble c_dznrm2( const CBLAS_INT N, const void *X, const CBLAS_INT strideX );\n```\n\n#### c_dznrm2_ndarray( N, \\*X, strideX, offsetX )\n\nComputes the L2-norm of a complex double-precision floating-point vector using alternative indexing semantics.\n\n```c\nconst double X[] = { 0.3, 0.1, 0.5, 0.0, 0.0, 0.5, 0.0, 0.2 };\n\ndouble norm = c_dznrm2_ndarray( 4, (void *)X, 1, 0 );\n// returns 0.8\n```\n\nThe function accepts the following arguments:\n\n-   **N**: `[in] CBLAS_INT` number of indexed elements.\n-   **X**: `[in] void*` input array.\n-   **strideX**: `[in] CBLAS_INT` index increment for `X`.\n-   **offsetX**: `[in] CBLAS_INT` starting index for `X`.\n\n```c\ndouble c_dznrm2_ndarray( const CBLAS_INT N, const void *X, const CBLAS_INT strideX, const CBLAS_INT offsetX );\n```\n\n\u003c/section\u003e\n\n\u003c!-- /.usage --\u003e\n\n\u003c!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. --\u003e\n\n\u003csection class=\"notes\"\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.notes --\u003e\n\n\u003c!-- C API usage examples. --\u003e\n\n\u003csection class=\"examples\"\u003e\n\n### Examples\n\n```c\n#include \"stdlib/blas/base/dznrm2.h\"\n#include \u003cstdio.h\u003e\n\nint main( void ) {\n    // Create a strided array of interleaved real and imaginary components:\n    const double X[] = { 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 };\n\n    // Specify the number of elements:\n    const int N = 4;\n\n    // Specify stride length:\n    const int strideX = 1;\n\n    // Compute the L2-norm:\n    double norm = c_dznrm2( N, (void *)X, strideX );\n\n    // Print the result:\n    printf( \"L2-norm: %lf\\n\", norm );\n\n    // Compute the L2-norm using alternative indexing semantics:\n    norm = c_dznrm2_ndarray( N, (void *)X, -strideX, N-1 );\n\n    // Print the result:\n    printf( \"L2-norm: %lf\\n\", norm );\n}\n```\n\n\u003c/section\u003e\n\n\u003c!-- /.examples --\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.c --\u003e\n\n* * *\n\n\u003csection class=\"references\"\u003e\n\n## References\n\n-   Blue, James L. 1978. \"A Portable Fortran Program to Find the Euclidean Norm of a Vector.\" _ACM Transactions on Mathematical Software_ 4 (1). New York, NY, USA: Association for Computing Machinery: 15–23. doi:[10.1145/355769.355771][@blue:1978a].\n-   Anderson, Edward. 2017. \"Algorithm 978: Safe Scaling in the Level 1 BLAS.\" _ACM Transactions on Mathematical Software_ 44 (1). New York, NY, USA: Association for Computing Machinery: 1–28. doi:[10.1145/3061665][@anderson:2017a].\n\n\u003c/section\u003e\n\n\u003c!-- /.references --\u003e\n\n\u003c!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. --\u003e\n\n\u003csection class=\"related\"\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.related --\u003e\n\n\u003c!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. --\u003e\n\n\n\u003csection class=\"main-repo\" \u003e\n\n* * *\n\n## Notice\n\nThis 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.\n\nFor 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].\n\n#### Community\n\n[![Chat][chat-image]][chat-url]\n\n---\n\n## License\n\nSee [LICENSE][stdlib-license].\n\n\n## Copyright\n\nCopyright \u0026copy; 2016-2026. The Stdlib [Authors][stdlib-authors].\n\n\u003c/section\u003e\n\n\u003c!-- /.stdlib --\u003e\n\n\u003c!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. --\u003e\n\n\u003csection class=\"links\"\u003e\n\n[npm-image]: http://img.shields.io/npm/v/@stdlib/blas-base-dznrm2.svg\n[npm-url]: https://npmjs.org/package/@stdlib/blas-base-dznrm2\n\n[test-image]: https://github.com/stdlib-js/blas-base-dznrm2/actions/workflows/test.yml/badge.svg?branch=main\n[test-url]: https://github.com/stdlib-js/blas-base-dznrm2/actions/workflows/test.yml?query=branch:main\n\n[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/blas-base-dznrm2/main.svg\n[coverage-url]: https://codecov.io/github/stdlib-js/blas-base-dznrm2?branch=main\n\n\u003c!--\n\n[dependencies-image]: https://img.shields.io/david/stdlib-js/blas-base-dznrm2.svg\n[dependencies-url]: https://david-dm.org/stdlib-js/blas-base-dznrm2/main\n\n--\u003e\n\n[chat-image]: https://img.shields.io/badge/zulip-join_chat-brightgreen.svg\n[chat-url]: https://stdlib.zulipchat.com\n\n[stdlib]: https://github.com/stdlib-js/stdlib\n\n[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors\n\n[umd]: https://github.com/umdjs/umd\n[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules\n\n[deno-url]: https://github.com/stdlib-js/blas-base-dznrm2/tree/deno\n[deno-readme]: https://github.com/stdlib-js/blas-base-dznrm2/blob/deno/README.md\n[umd-url]: https://github.com/stdlib-js/blas-base-dznrm2/tree/umd\n[umd-readme]: https://github.com/stdlib-js/blas-base-dznrm2/blob/umd/README.md\n[esm-url]: https://github.com/stdlib-js/blas-base-dznrm2/tree/esm\n[esm-readme]: https://github.com/stdlib-js/blas-base-dznrm2/blob/esm/README.md\n[branches-url]: https://github.com/stdlib-js/blas-base-dznrm2/blob/main/branches.md\n\n[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/blas-base-dznrm2/main/LICENSE\n\n[blas]: http://www.netlib.org/blas\n\n[dznrm2]: https://netlib.org/lapack/explore-html//d1/d2a/group__nrm2_ga7f9f9febc6dc1836c9f5e7c1aa00b743.html\n\n[@stdlib/array/complex128]: https://github.com/stdlib-js/array-complex128\n\n[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray\n\n[@blue:1978a]: https://doi.org/10.1145/355769.355771\n\n[@anderson:2017a]: https://doi.org/10.1145/3061665\n\n\u003c/section\u003e\n\n\u003c!-- /.links --\u003e\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fstdlib-js%2Fblas-base-dznrm2","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fstdlib-js%2Fblas-base-dznrm2","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fstdlib-js%2Fblas-base-dznrm2/lists"}