@stdlib/array/base/take-indexed/README.md

Arrays.

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# takeIndexed

> Take elements from an indexed array.

<section class="usage">

## Usage

```javascript
var takeIndexed = require( '@stdlib/array/base/take-indexed' );
```

#### takeIndexed( x, indices )

Takes elements from an indexed array.

```javascript
var x = [ 1, 2, 3, 4 ];

var y = takeIndexed( x, [ 1, 3 ] );
// returns [ 2, 4 ]
```

If `indices` is an empty array, the function returns an empty array.

```javascript
var x = [ 1, 2, 3, 4 ];

var y = takeIndexed( x, [] );
// returns []
```

</section>

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<section class="notes">

## Notes

-   The function does **not** perform bounds checking. If an index is less than zero or greater than the maximum index of `x`, the value of the corresponding element in the output array is undefined.
-   An _indexed_ array-like object is a data structure in which one retrieves elements via integer indices using bracket `[]` notation (e.g., `Float64Array`, `Int32Array`, `Array`, etc). This is in contrast to an _accessor_ array-like object in which one retrieves elements using `get` and `set` methods (e.g., `Complex64Array` and `Complex128Array`).

</section>

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<section class="examples">

## Examples

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

```javascript
var filledBy = require( '@stdlib/array/base/filled-by' );
var discreteUniform = require( '@stdlib/random/base/discrete-uniform' );
var linspace = require( '@stdlib/array/base/linspace' );
var takeIndexed = require( '@stdlib/array/base/take-indexed' );

// Generate a linearly spaced array:
var x = linspace( 0, 100, 11 );

// Generate an array of random indices:
var N = discreteUniform( 5, 15 );
var indices = filledBy( N, discreteUniform.factory( 0, x.length-1 ) );

// Take a random sample of elements from `x`:
var y = takeIndexed( x, indices );

console.log( x );
console.log( indices );
console.log( y );
```

</section>

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