Turning multidimensional array into one-dimensional array [duplicate]

Question

I've been banging my head on this one for a while now.

I have this multidimensional array:

Array (     [0] => Array         (             [0] => foo             [1] => bar             [2] => hello         )      [1] => Array         (             [0] => world             [1] => love         )      [2] => Array         (             [0] => stack             [1] => overflow             [2] => yep             [3] => man         ) 

And I need to get this:

Array (     [0] => foo     [1] => bar     [2] => hello     [3] => world     [4] => love     [5] => stack     [6] => overflow     [7] => yep     [8] => man ) 

Any ideas?

All other solutions I found solve multidimensional arrays with different keys. My arrays use simple numeric keys only.

Answer 1

array_reduce($array, 'array_merge', array()) 

Example:

$a = array(array(1, 2, 3), array(4, 5, 6)); $result = array_reduce($a, 'array_merge', array()); 

Result:

array[1, 2, 3, 4, 5, 6]; 

Answer 2

The PHP array_merge^­Docs function can flatten your array:

$flat = call_user_func_array('array_merge', $array); 

In case the original array has a higher depth than 2 levels, the SPL in PHP has a RecursiveArrayIterator you can use to flatten it:

$flat = iterator_to_array(new RecursiveIteratorIterator(new RecursiveArrayIterator($array)), 0); 

See as well: How to Flatten a Multidimensional Array?.