Iterating numeric keys only in arrays with mixed numeric, associative keys?

[Kadence]

Is there a good way to iterate over the numeric keys only in an array with mixed numeric and associative keys, other than brute force where you use do a foreach() and then use something like is_numeric() the individual keys?

For instance I have an array like

$array = array('0'=>'zero', '1'=>'one', '2'=>'two', '3'='three', 'fruit'=>'orange', 'color'=>'green', 'plant'=>'grass'); 

And I want to iterate over the 0, 1, 2, and 3 elements only.

[grantwparks]

I just tried the following and the result is an array with only the numerically-indexed entries:

$array = array('0'=>'zero', '1'=>'one', '2'=>'two', '4'=>'three', 'fruit'=>'orange', 'color'=>'green', 'plant'=>'grass');
$array2 = array_values($array);
$array3 = array_intersect_key($array, $array2);

[09-May-2009 20:36:00] Array1
(
[0] => zero
[1] => one
[2] => two
[4] => three
[fruit] => orange
[color] => green
[plant] => grass
)

[09-May-2009 20:36:00] Array2
(
[0] => zero
[1] => one
[2] => two
[3] => three
[4] => orange
[5] => green
[6] => grass
)

[09-May-2009 20:36:00] Array3
(
[0] => zero
[1] => one
[2] => two
[4] => three
)

[crmalibu]

If numeric keys are sequential and no gaps exist between integers, you could just use a standard for loop. But otherwise, here's an alternative which comes to mind

$new = array_combine(array_filter(array_keys($array), 'is_int'), $array); 

Personally I think I would just use a foreach and check the key with is_int() inside the loop. It's painfully obvious and clear what you're doing in that case, unlike the snippit I just posted. It's probably also faster.