# unflatten
> Return a read-only view of an input [ndarray][@stdlib/ndarray/ctor] in which a specified dimension is expanded over multiple dimensions.
## Usage
```javascript
var unflatten = require( '@stdlib/ndarray/unflatten' );
```
#### unflatten( x, dim, sizes )
Returns a read-only view of an input [ndarray][@stdlib/ndarray/ctor] in which a specified dimension is expanded over multiple dimensions.
```javascript
var array = require( '@stdlib/ndarray/array' );
// Create a 1-dimensional ndarray:
var x = array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
// returns [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ]
// Unflatten the first dimension:
var y = unflatten( x, 0, [ 2, 3 ] );
// returns [ [ 1.0, 2.0, 3.0 ], [ 4.0, 5.0, 6.0 ] ]
```
The function accepts the following arguments:
- **x**: input [ndarray][@stdlib/ndarray/ctor].
- **dim**: dimension to be unflattened. If provided an integer less than zero, the dimension index is resolved relative to the last dimension, with the last dimension corresponding to the value `-1`.
- **sizes**: new shape of the unflattened dimension.
## Examples
```javascript
var uniform = require( '@stdlib/random/uniform' );
var ndarray2array = require( '@stdlib/ndarray/to-array' );
var unflatten = require( '@stdlib/ndarray/unflatten' );
var x = uniform( [ 12 ], -10.0, 10.0 );
console.log( ndarray2array( x ) );
var y = unflatten( x, 0, [ 3, 4 ] );
console.log( ndarray2array( y ) );
```
[@stdlib/ndarray/ctor]: https://github.com/stdlib-js/ndarray/tree/main/ctor