npm package: @stdlib/ndarray-base-to-normalized-indices
Description: Normalize a list of indices to the interval [0,max].
Author: The Stdlib Authors
Latest version: 0.1.1

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# toNormalizedIndices

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> Normalize a list of indices to the interval `[0,max]`.

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<section class="intro">

</section>

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<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-base-to-normalized-indices
```

</section>

<section class="usage">

## Usage

```javascript
var toNormalizedIndices = require( '@stdlib/ndarray-base-to-normalized-indices' );
```

#### toNormalizedIndices( indices, max )

Normalizes a list of indices to the interval `[0,max]`.

```javascript
var idx = toNormalizedIndices( [ 2, -5 ], 10 );
// returns [ 2, 6 ]
```

If provided an out-of-bounds index, the function normalizes the index to `-1`.

```javascript
var idx = toNormalizedIndices( [ 15, -15 ], 10 );
// returns [ -1, -1 ]
```

</section>

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<section class="notes">

## Notes

-   During normalization, a negative index is converted to a nonnegative index according to `max + idx + 1`. If, after normalization, the resolved index is still negative, the value is considered out-of-bounds.

</section>

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<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var toNormalizedIndices = require( '@stdlib/ndarray-base-to-normalized-indices' );

// Generate a list of random indices:
var idx = discreteUniform( 100, -20, 20, {
    'dtype': 'generic'
});

// Normalize each index to the interval `[0, 15]`:
var out = toNormalizedIndices( idx, 15 );

// Print the results...
var i;
for ( i = 0; i < idx.length; i++ ) {
    console.log( '%d => [%d, %d] => %d', idx[ i ], 0, 15, out[ i ] );
}
```

</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.

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## License

See [LICENSE][stdlib-license].


## Copyright

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

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