- print_r: documentation ( source)
- array_filter: documentation ( source)
- array_diff: documentation ( source)
<?php
print_r(array_diff(array(312, 401, 1599, 3), array(401) )); // returns [312, 1599, 3]
print_r(array_filter(array(312, 401, 1599, 3), function($i){return $i != 401;}));
print_r(array_delete( array(312, 401, 1599, 3), 401 ) );