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https://github.com/stdlib-js/stats-base-minabs

Calculate the minimum absolute value of a strided array.
https://github.com/stdlib-js/stats-base-minabs

abs absolute array domain extent extremes javascript math mathematics min minimum node node-js nodejs range statistics stats stdlib strided strided-array

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Calculate the minimum absolute value of a strided array.

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README 

        



  

    About stdlib...

  

  
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# minabs



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



> Calculate the minimum absolute value of a strided array.



## Installation



```bash

npm install @stdlib/stats-base-minabs

```



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 minabs = require( '@stdlib/stats-base-minabs' );

```



#### minabs( N, x, stride )



Computes the minimum absolute value of a strided array `x`.



```javascript

var x = [ 1.0, -2.0, 2.0 ];

var N = x.length;



var v = minabs( N, x, 1 );

// returns 1.0

```



The function has the following parameters:



-   **N**: number of indexed elements.

-   **x**: input [`Array`][mdn-array] or [`typed array`][mdn-typed-array].

-   **stride**: index increment for `x`.



The `N` and `stride` parameters determine which elements in `x` are accessed at runtime. For example, to compute the minimum absolute value of every other element in `x`,



```javascript

var floor = require( '@stdlib/math-base-special-floor' );



var x = [ 1.0, 2.0, 2.0, -7.0, -2.0, 3.0, 4.0, 2.0 ];

var N = floor( x.length / 2 );



var v = minabs( N, x, 2 );

// returns 1.0

```



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' );

var floor = require( '@stdlib/math-base-special-floor' );



var x0 = new Float64Array( [ 2.0, 1.0, 2.0, -2.0, -2.0, 2.0, 3.0, 4.0 ] );

var x1 = new Float64Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element



var N = floor( x0.length / 2 );



var v = minabs( N, x1, 2 );

// returns 1.0

```



#### minabs.ndarray( N, x, stride, offset )



Computes the minimum absolute value of a strided array using alternative indexing semantics.



```javascript

var x = [ 1.0, -2.0, 2.0 ];

var N = x.length;



var v = minabs.ndarray( N, x, 1, 0 );

// returns 1.0

```



The function has the following additional parameters:



-   **offset**: starting index for `x`.



While [`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 calculate the minimum absolute value for every other value in `x` starting from the second value



```javascript

var floor = require( '@stdlib/math-base-special-floor' );



var x = [ 2.0, 1.0, 2.0, -2.0, -2.0, 2.0, 3.0, 4.0 ];

var N = floor( x.length / 2 );



var v = minabs.ndarray( N, x, 2, 1 );

// returns 1.0

```



## Notes



-   If `N <= 0`, both functions return `NaN`.

-   Depending on the environment, the typed versions ([`dminabs`][@stdlib/stats/base/dminabs], [`sminabs`][@stdlib/stats/base/sminabs], etc.) are likely to be significantly more performant.



## Examples



```javascript

var randu = require( '@stdlib/random-base-randu' );

var round = require( '@stdlib/math-base-special-round' );

var Float64Array = require( '@stdlib/array-float64' );

var minabs = require( '@stdlib/stats-base-minabs' );



var x;

var i;



x = new Float64Array( 10 );

for ( i = 0; i < x.length; i++ ) {

    x[ i ] = round( (randu()*100.0) - 50.0 );

}

console.log( x );



var v = minabs( x.length, x, 1 );

console.log( v );

```



* * *



## See Also



-   [`@stdlib/stats-base/dminabs`][@stdlib/stats/base/dminabs]: calculate the minimum absolute value of a double-precision floating-point strided array.

-   [`@stdlib/stats-base/maxabs`][@stdlib/stats/base/maxabs]: calculate the maximum absolute value of a strided array.

-   [`@stdlib/stats-base/min`][@stdlib/stats/base/min]: calculate the minimum value of a strided array.

-   [`@stdlib/stats-base/nanminabs`][@stdlib/stats/base/nanminabs]: calculate the minimum absolute value of a strided array, ignoring NaN values.

-   [`@stdlib/stats-base/sminabs`][@stdlib/stats/base/sminabs]: calculate the minimum absolute value of a single-precision floating-point strided 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 © 2016-2024. The Stdlib [Authors][stdlib-authors].



[npm-image]: http://img.shields.io/npm/v/@stdlib/stats-base-minabs.svg

[npm-url]: https://npmjs.org/package/@stdlib/stats-base-minabs



[test-image]: https://github.com/stdlib-js/stats-base-minabs/actions/workflows/test.yml/badge.svg?branch=main

[test-url]: https://github.com/stdlib-js/stats-base-minabs/actions/workflows/test.yml?query=branch:main



[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/stats-base-minabs/main.svg

[coverage-url]: https://codecov.io/github/stdlib-js/stats-base-minabs?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/stats-base-minabs/tree/deno

[deno-readme]: https://github.com/stdlib-js/stats-base-minabs/blob/deno/README.md

[umd-url]: https://github.com/stdlib-js/stats-base-minabs/tree/umd

[umd-readme]: https://github.com/stdlib-js/stats-base-minabs/blob/umd/README.md

[esm-url]: https://github.com/stdlib-js/stats-base-minabs/tree/esm

[esm-readme]: https://github.com/stdlib-js/stats-base-minabs/blob/esm/README.md

[branches-url]: https://github.com/stdlib-js/stats-base-minabs/blob/main/branches.md



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



[mdn-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array



[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray



[@stdlib/stats/base/dminabs]: https://github.com/stdlib-js/stats-base-dminabs



[@stdlib/stats/base/maxabs]: https://github.com/stdlib-js/stats-base-maxabs



[@stdlib/stats/base/min]: https://github.com/stdlib-js/stats-base-min



[@stdlib/stats/base/nanminabs]: https://github.com/stdlib-js/stats-base-nanminabs



[@stdlib/stats/base/sminabs]: https://github.com/stdlib-js/stats-base-sminabs