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

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# toUniqueNormalizedIndices

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> Return a list of unique indices after normalizing 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-unique-normalized-indices
```

</section>

<section class="usage">

## Usage

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

#### toUniqueNormalizedIndices( indices, max )

Returns a list of unique indices after normalizing to the interval `[0,max]`.

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

If provided an out-of-bounds index, the function returns `null`.

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

</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.
-   When provided valid indices, the function always returns a "generic" array.
-   The function preserves provided index order.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

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

// Generate a list of random indices:
var idx = discreteUniform( 100, -15, 15, {
    'dtype': 'generic'
});
console.log( idx );

// Generate a list of unique indices normalized to the interval `[0, 15]`:
var out = toUniqueNormalizedIndices( idx, 15 );
console.log( out );
```

</section>

<!-- /.examples -->

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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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