@stdlib/array/base/at/README.md

Arrays.

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# at

> Return an element from an array.

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## Usage

```javascript
var at = require( '@stdlib/array/base/at' );
```

#### at( x, index )

Returns an element from an array.

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

var out = at( x, 0 );
// returns 1

out = at( x, 1 );
// returns 2

out = at( x, -2 );
// returns 3
```

The function accepts the following arguments:

-   **x**: an input array.
-   **index**: element index.

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## Notes

-   If provided an array-like object having an `at` method , the function defers execution to that method and assumes that the method has the following signature:

    ```text
    x.at( index )
    ```

    If provided an array-like object without an `at` method, the function normalizes a provided index and returns a specified element.

-   Negative indices are resolved relative to the last array element, with the last element corresponding to `-1`.

-   If provided out-of-bounds indices, the function always returns `undefined`.

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## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var at = require( '@stdlib/array/base/at' );

// Define an array:
var x = discreteUniform( 10, -100, 100 );

// Define an array containing random index values:
var indices = discreteUniform( 100, -x.length, x.length-1 );

// Randomly selected values from the input array:
var i;
for ( i = 0; i < indices.length; i++ ) {
    console.log( 'x[%d] = %d', indices[ i ], at( x, indices[ i ] ) );
}
```

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