{"id":30459669,"url":"https://github.com/stdlib-js/stats-min-by","last_synced_at":"2026-04-14T18:34:32.142Z","repository":{"id":310128215,"uuid":"1034930693","full_name":"stdlib-js/stats-min-by","owner":"stdlib-js","description":"Compute the minimum value along one or more ndarray dimensions according to a callback function.","archived":false,"fork":false,"pushed_at":"2026-04-11T03:43:27.000Z","size":3823,"stargazers_count":0,"open_issues_count":0,"forks_count":0,"subscribers_count":0,"default_branch":"main","last_synced_at":"2026-04-11T05:30:36.438Z","etag":null,"topics":["domain","extent","extremes","javascript","math","mathematics","min","minimum","ndarray","node","node-js","nodejs","range","statistics","stats","stdlib"],"latest_commit_sha":null,"homepage":"https://github.com/stdlib-js/stdlib","language":"JavaScript","has_issues":false,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"apache-2.0","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/stdlib-js.png","metadata":{"files":{"readme":"README.md","changelog":"CHANGELOG.md","contributing":"CONTRIBUTING.md","funding":null,"license":"LICENSE","code_of_conduct":"CODE_OF_CONDUCT.md","threat_model":null,"audit":null,"citation":"CITATION.cff","codeowners":null,"security":"SECURITY.md","support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null,"zenodo":null,"notice":"NOTICE","maintainers":null,"copyright":null,"agents":null,"dco":null,"cla":null},"funding":{"github":["stdlib-js"],"open_collective":"stdlib","tidelift":"npm/@stdlib/stdlib"}},"created_at":"2025-08-09T09:35:12.000Z","updated_at":"2026-04-11T03:19:07.000Z","dependencies_parsed_at":"2025-08-15T23:44:03.569Z","dependency_job_id":"f94d7750-a6ae-42dc-a228-ae88007fc3d2","html_url":"https://github.com/stdlib-js/stats-min-by","commit_stats":null,"previous_names":["stdlib-js/stats-min-by"],"tags_count":8,"template":false,"template_full_name":null,"purl":"pkg:github/stdlib-js/stats-min-by","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstats-min-by","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstats-min-by/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstats-min-by/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstats-min-by/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/stdlib-js","download_url":"https://codeload.github.com/stdlib-js/stats-min-by/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Fstats-min-by/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":31810739,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-04-14T18:05:02.291Z","status":"ssl_error","status_checked_at":"2026-04-14T18:05:01.765Z","response_time":153,"last_error":"SSL_read: 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":["domain","extent","extremes","javascript","math","mathematics","min","minimum","ndarray","node","node-js","nodejs","range","statistics","stats","stdlib"],"created_at":"2025-08-23T18:48:53.771Z","updated_at":"2026-04-14T18:34:32.135Z","avatar_url":"https://github.com/stdlib-js.png","language":"JavaScript","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) 2025 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# minBy\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 minimum value along one or more [ndarray][@stdlib/ndarray/ctor] dimensions according to a callback function.\n\n\u003csection class=\"installation\"\u003e\n\n## Installation\n\n```bash\nnpm install @stdlib/stats-min-by\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 minBy = require( '@stdlib/stats-min-by' );\n```\n\n#### minBy( x\\[, options], clbk\\[, thisArg] )\n\nComputes the minimum value along one or more [ndarray][@stdlib/ndarray/ctor] dimensions according to a callback function.\n\n```javascript\nvar array = require( '@stdlib/ndarray-array' );\n\nvar x = array( [ -1.0, 2.0, -3.0 ] );\n\nfunction clbk( v ) {\n    return v * 2.0;\n}\n\nvar y = minBy( x, clbk );\n// returns \u003cndarray\u003e[ -6.0 ]\n```\n\nThe function has the following parameters:\n\n-   **x**: input [ndarray][@stdlib/ndarray/ctor].\n-   **options**: function options (_optional_).\n-   **clbk**: callback function.\n-   **thisArg**: callback function execution context (_optional_).\n\nThe invoked callback is provided three arguments:\n\n-   **value**: current array element.\n-   **index**: current array element index.\n-   **array**: input ndarray.\n\nTo set the callback execution context, provide a `thisArg`.\n\n\u003c!-- eslint-disable no-invalid-this --\u003e\n\n```javascript\nvar array = require( '@stdlib/ndarray-array' );\n\nvar x = array( [ -1.0, 2.0, -3.0 ] );\n\nfunction clbk( v ) {\n    this.count += 1;\n    return v * 2.0;\n}\n\nvar ctx = {\n    'count': 0\n};\nvar y = minBy( x, clbk, ctx );\n// returns \u003cndarray\u003e[ -6.0 ]\n\nvar count = ctx.count;\n// returns 3\n```\n\nThe function accepts the following options:\n\n-   **dims**: list of dimensions over which to perform a reduction. If not provided, the function performs a reduction over all elements in a provided input [ndarray][@stdlib/ndarray/ctor].\n-   **dtype**: output ndarray [data type][@stdlib/ndarray/dtypes]. Must be a real-valued or \"generic\" [data type][@stdlib/ndarray/dtypes].\n-   **keepdims**: boolean indicating whether the reduced dimensions should be included in the returned [ndarray][@stdlib/ndarray/ctor] as singleton dimensions. Default: `false`.\n\nBy default, the function performs a reduction over all elements in a provided input [ndarray][@stdlib/ndarray/ctor]. To perform a reduction over specific dimensions, provide a `dims` option.\n\n```javascript\nvar array = require( '@stdlib/ndarray-array' );\n\nfunction clbk( v ) {\n    return v * 100.0;\n}\n\nvar x = array( [ -1.0, 2.0, -3.0, 4.0 ], {\n    'shape': [ 2, 2 ],\n    'order': 'row-major'\n});\n// returns \u003cndarray\u003e[ [ -1.0, 2.0 ], [ -3.0, 4.0 ] ]\n\nvar opts = {\n    'dims': [ 0 ]\n};\nvar y = minBy( x, opts, clbk );\n// returns \u003cndarray\u003e[ -300.0, 200.0 ]\n\nopts = {\n    'dims': [ 1 ]\n};\ny = minBy( x, opts, clbk );\n// returns \u003cndarray\u003e[ -100.0, -300.0 ]\n\nopts = {\n    'dims': [ 0, 1 ]\n};\ny = minBy( x, opts, clbk );\n// returns \u003cndarray\u003e[ -300.0 ]\n```\n\nBy default, the function excludes reduced dimensions from the output [ndarray][@stdlib/ndarray/ctor]. To include the reduced dimensions as singleton dimensions, set the `keepdims` option to `true`.\n\n```javascript\nvar array = require( '@stdlib/ndarray-array' );\n\nfunction clbk( v ) {\n    return v * 100.0;\n}\n\nvar x = array( [ -1.0, 2.0, -3.0, 4.0 ], {\n    'shape': [ 2, 2 ],\n    'order': 'row-major'\n});\n// returns \u003cndarray\u003e[ [ -1.0, 2.0 ], [ -3.0, 4.0 ] ]\n\nvar opts = {\n    'dims': [ 0 ],\n    'keepdims': true\n};\nvar y = minBy( x, opts, clbk );\n// returns \u003cndarray\u003e[ [ -300.0, 200.0 ] ]\n\nopts = {\n    'dims': [ 1 ],\n    'keepdims': true\n};\ny = minBy( x, opts, clbk );\n// returns \u003cndarray\u003e[ [ -100.0 ], [ -300.0 ] ]\n\nopts = {\n    'dims': [ 0, 1 ],\n    'keepdims': true\n};\ny = minBy( x, opts, clbk );\n// returns \u003cndarray\u003e[ [ -300.0 ] ]\n```\n\nBy default, the function returns an [ndarray][@stdlib/ndarray/ctor] having a [data type][@stdlib/ndarray/dtypes] determined by the function's output data type [policy][@stdlib/ndarray/output-dtype-policies]. To override the default behavior, set the `dtype` option.\n\n```javascript\nvar getDType = require( '@stdlib/ndarray-dtype' );\nvar array = require( '@stdlib/ndarray-array' );\n\nfunction clbk( v ) {\n    return v * 100.0;\n}\n\nvar x = array( [ -1.0, 2.0, -3.0 ], {\n    'dtype': 'generic'\n});\n\nvar opts = {\n    'dtype': 'float64'\n};\nvar y = minBy( x, opts, clbk );\n// returns \u003cndarray\u003e\n\nvar dt = String( getDType( y ) );\n// returns 'float64'\n```\n\n#### minBy.assign( x, out\\[, options], clbk\\[, thisArg] )\n\nComputes the minimum value along one or more [ndarray][@stdlib/ndarray/ctor] dimensions according to a callback function and assigns results to a provided output [ndarray][@stdlib/ndarray/ctor].\n\n```javascript\nvar array = require( '@stdlib/ndarray-array' );\nvar zeros = require( '@stdlib/ndarray-zeros' );\n\nfunction clbk( v ) {\n    return v * 100.0;\n}\n\nvar x = array( [ -1.0, 2.0, -3.0 ] );\nvar y = zeros( [] );\n\nvar out = minBy.assign( x, y, clbk );\n// returns \u003cndarray\u003e[ -300.0 ]\n\nvar bool = ( out === y );\n// returns true\n```\n\nThe method has the following parameters:\n\n-   **x**: input [ndarray][@stdlib/ndarray/ctor].\n-   **out**: output [ndarray][@stdlib/ndarray/ctor].\n-   **options**: function options (_optional_).\n-   **clbk**: callback function.\n-   **thisArg**: callback execution context (_optional_).\n\nThe method accepts the following options:\n\n-   **dims**: list of dimensions over which to perform a reduction. If not provided, the function performs a reduction over all elements in a provided input [ndarray][@stdlib/ndarray/ctor].\n\n\u003c/section\u003e\n\n\u003c!-- /.usage --\u003e\n\n\u003csection class=\"notes\"\u003e\n\n## Notes\n\n-   A provided callback function should return a numeric value.\n-   If a provided callback function does not return any value (or equivalently, explicitly returns `undefined`), the value is **ignored**.\n-   Setting the `keepdims` option to `true` can be useful when wanting to ensure that the output [ndarray][@stdlib/ndarray/ctor] is [broadcast-compatible][@stdlib/ndarray/base/broadcast-shapes] with ndarrays having the same shape as the input [ndarray][@stdlib/ndarray/ctor].\n-   The output data type [policy][@stdlib/ndarray/output-dtype-policies] only applies to the main function and specifies that, by default, the function must return an [ndarray][@stdlib/ndarray/ctor] having a real-valued or \"generic\" [data type][@stdlib/ndarray/dtypes]. For the `assign` method, the output [ndarray][@stdlib/ndarray/ctor] is allowed to have any supported output [data type][@stdlib/ndarray/dtypes].\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 filledarrayBy = require( '@stdlib/array-filled-by' );\nvar discreteUniform = require( '@stdlib/random-base-discrete-uniform' );\nvar getDType = require( '@stdlib/ndarray-dtype' );\nvar ndarray2array = require( '@stdlib/ndarray-to-array' );\nvar ndarray = require( '@stdlib/ndarray-ctor' );\nvar minBy = require( '@stdlib/stats-min-by' );\n\n// Define a function for generating an object having a random value:\nfunction random() {\n    return {\n        'value': discreteUniform( 0, 20 )\n    };\n}\n\n// Generate an array of random objects:\nvar xbuf = filledarrayBy( 25, 'generic', random );\n\n// Wrap in an ndarray:\nvar x = new ndarray( 'generic', xbuf, [ 5, 5 ], [ 5, 1 ], 0, 'row-major' );\nconsole.log( ndarray2array( x ) );\n\n// Define an accessor function:\nfunction accessor( v ) {\n    return v.value * 100;\n}\n\n// Perform a reduction:\nvar opts = {\n    'dims': [ 0 ]\n};\nvar y = minBy( x, opts, accessor );\n\n// Resolve the output array data type:\nvar dt = getDType( y );\nconsole.log( dt );\n\n// Print the results:\nconsole.log( ndarray2array( y ) );\n```\n\n\u003c/section\u003e\n\n\u003c!-- /.examples --\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/stats-min-by.svg\n[npm-url]: https://npmjs.org/package/@stdlib/stats-min-by\n\n[test-image]: https://github.com/stdlib-js/stats-min-by/actions/workflows/test.yml/badge.svg?branch=main\n[test-url]: https://github.com/stdlib-js/stats-min-by/actions/workflows/test.yml?query=branch:main\n\n[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/stats-min-by/main.svg\n[coverage-url]: https://codecov.io/github/stdlib-js/stats-min-by?branch=main\n\n\u003c!--\n\n[dependencies-image]: https://img.shields.io/david/stdlib-js/stats-min-by.svg\n[dependencies-url]: https://david-dm.org/stdlib-js/stats-min-by/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/stats-min-by/tree/deno\n[deno-readme]: https://github.com/stdlib-js/stats-min-by/blob/deno/README.md\n[umd-url]: https://github.com/stdlib-js/stats-min-by/tree/umd\n[umd-readme]: https://github.com/stdlib-js/stats-min-by/blob/umd/README.md\n[esm-url]: https://github.com/stdlib-js/stats-min-by/tree/esm\n[esm-readme]: https://github.com/stdlib-js/stats-min-by/blob/esm/README.md\n[branches-url]: https://github.com/stdlib-js/stats-min-by/blob/main/branches.md\n\n[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/stats-min-by/main/LICENSE\n\n[@stdlib/ndarray/ctor]: https://github.com/stdlib-js/ndarray-ctor\n\n[@stdlib/ndarray/dtypes]: https://github.com/stdlib-js/ndarray-dtypes\n\n[@stdlib/ndarray/output-dtype-policies]: https://github.com/stdlib-js/ndarray-output-dtype-policies\n\n[@stdlib/ndarray/base/broadcast-shapes]: https://github.com/stdlib-js/ndarray-base-broadcast-shapes\n\n\u003c/section\u003e\n\n\u003c!-- /.links --\u003e\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fstdlib-js%2Fstats-min-by","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fstdlib-js%2Fstats-min-by","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fstdlib-js%2Fstats-min-by/lists"}