npm package: @stdlib/ndarray-base-wrap-index
Description: Wrap an index on the interval [0,max].
Author: The Stdlib Authors
Latest version: 0.2.3

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# wrapIndex

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> Wrap an index on the interval `[0,max]`.

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</section>

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<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-base-wrap-index
```

</section>

<section class="usage">

## Usage

```javascript
var wrapIndex = require( '@stdlib/ndarray-base-wrap-index' );
```

#### wrapIndex( idx, max )

Wraps an index on the interval `[0,max]`.

```javascript
var idx = wrapIndex( 2, 10 );
// returns 2

idx = wrapIndex( -5, 10 );
// returns 6

idx = wrapIndex( 15, 10 );
// returns 4
```

</section>

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<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random-base-discrete-uniform' );
var wrapIndex = require( '@stdlib/ndarray-base-wrap-index' );

var idx;
var out;
var i;

for ( i = 0; i < 100; i++ ) {
    idx = discreteUniform( -20, 20 );
    out = wrapIndex( idx, 9 );
    console.log( '%d => [%d,%d] => %d', idx, 0, 9, out );
}
```

</section>

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* * *

## 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].

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---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

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