Remove empty values from a multidimensional array - php

Question

I researched a lot of questions and answers posted on stackoverflow about the subject but I still couldn't find a solution to the following problem.
I need to generate an array from the text provided by this link, minus some specific lines: https://code.wireshark.org/review/gitweb?p=wireshark.git;a=blob_plain;f=manuf. This part I was able to do.
PHP Code:
$arr = file('https://code.wireshark.org/review/gitweb?p=wireshark.git;a=blob_plain;f=manuf');
$arr = preg_replace('/^(?![a-z0-9]{2}:[a-z0-9]{2}:[a-z0-9]{2}\s).*$/i', '', $arr);
$arr = preg_replace ('/#/i', '',$arr);
$arr = preg_replace('/\t+/', ' ', $arr);
$arr = preg_replace('/\s{2,}/', ' ', $arr);
$arr = preg_replace('/ /', '~', $arr, 2);
foreach ($arr as $field)
{
$macList[] = explode('~', $field);
}
echo "<pre>";
print_r($macList);
echo "</pre>";
The problem is that when I use print_r, the first 52 sub-arrays are empty, plus some dozens at the bottom. I can't figure out how to remove them.
Reduced print_r output, because the full output returns 25770 sub-arrays:
Array
(
[0] => Array
(
[0] =>
)
[1] => Array
(
[0] =>
)
[2] => Array
(
[0] =>
)
[3] => Array
(
[0] =>
)
[4] => Array
(
[0] =>
)
[5] => Array
(
[0] =>
)
[6] => Array
(
[0] =>
)
[7] => Array
(
[0] =>
)
[8] => Array
(
[0] =>
)
[9] => Array
(
[0] =>
)
[10] => Array
(
[0] =>
)
[11] => Array
(
[0] =>
)
[12] => Array
(
[0] =>
)
[13] => Array
(
[0] =>
)
[14] => Array
(
[0] =>
)
[15] => Array
(
[0] =>
)
[16] => Array
(
[0] =>
)
[17] => Array
(
[0] =>
)
[18] => Array
(
[0] =>
)
[19] => Array
(
[0] =>
)
[20] => Array
(
[0] =>
)
[21] => Array
(
[0] =>
)
[22] => Array
(
[0] =>
)
[23] => Array
(
[0] =>
)
[24] => Array
(
[0] =>
)
[25] => Array
(
[0] =>
)
[26] => Array
(
[0] =>
)
[27] => Array
(
[0] =>
)
[28] => Array
(
[0] =>
)
[29] => Array
(
[0] =>
)
[30] => Array
(
[0] =>
)
[31] => Array
(
[0] =>
)
[32] => Array
(
[0] =>
)
[33] => Array
(
[0] =>
)
[34] => Array
(
[0] =>
)
[35] => Array
(
[0] =>
)
[36] => Array
(
[0] =>
)
[37] => Array
(
[0] =>
)
[38] => Array
(
[0] =>
)
[39] => Array
(
[0] =>
)
[40] => Array
(
[0] =>
)
[41] => Array
(
[0] =>
)
[42] => Array
(
[0] =>
)
[43] => Array
(
[0] =>
)
[44] => Array
(
[0] =>
)
[45] => Array
(
[0] =>
)
[46] => Array
(
[0] =>
)
[47] => Array
(
[0] =>
)
[48] => Array
(
[0] =>
)
[49] => Array
(
[0] =>
)
[50] => Array
(
[0] =>
)
[51] => Array
(
[0] =>
)
[52] => Array
(
[0] => 00:00:00
[1] => 00:00:00
[2] => Officially Xerox, but 0:0:0:0:0:0 is more common
)
)
Question: How do I remove these 52 (0 to 51) empty arrays? Nothing I tried worked.

Answer 1

Rather than trying to remove the empty keys, instead dont add the empty arrays in the 1st place:
EDIT is seems the 'empty' arrays are not in fact empty, but instead contain a single element with a space character. To remove you can combine empty with trim , array_map and array_filter:
foreach ($arr as $field)
{
$temp = explode('~', $field);
if(!empty(array_filter(array_map('trim', $temp))))
{
$macList[] = $temp;
}
}
echo "<pre>";
print_r($macList);
echo "</pre>";

Answer 2

As an example of using array_filter() and assuming it is always an empty single element array:
$new_array = array_filter($array, function($elements) {
return !empty($elements[0]);
});