After array_filter(), how can I reset the keys to go in numerical order starting at 0
If you call array_values on your array, it will be reindexed from zero.
If you are using Array filter do it as follows
$NewArray = array_values(array_filter($OldArray));
Use array_values():
<?php
$array = array('foo', 'bar', 'baz');
$array = array_filter($array, function ($var) {
return $var !== 'bar';
});
print_r($array); // indexes 0 and 2
print_r(array_values($array)); // indexes 0 and 1