#this function unsets all the elements in a certain array but keeps the
#element in $keep
 
 
function myFilter($array, $keep){
   $result = array();
   foreach($array as $key => $val)   {
   if(is_array($val))      {
   $temp = array();
   $temp = myFilter($val, $keep);
   if(count($temp))         {
   $result[$key] = $temp;
   unset($temp);
   }
   }      else      {
   if($val == $keep)         {
   $result[$key] = $val;
   }
   }
   }
   return($result);
   }
 
#it works for multidimensional arrays aswell.
#try it.
 
#use your own array for this
#element use your own element.
 
$firstresult = myfilter($originalarray, $element);
echo "<pre>";
print_r($firstresult);
echo "</pre>";
 
 
#as you can see it unsets all the elements in the array but leaves the element
#however if you use this code in an multi dimensional array.
 
#what happens is that it only takes that array which has the element.
#now dont get me wrong, I want that. But I want it to overwrite the original
#array, but not the whole array only where the array was.
 
#example:
$originalarray[0][0] = $firstresult[0][0];
echo "<pre>";
print_r($originalarray);
echo "</pre>";
 
 
#as you can see there's a problem.
 
#PROBLEM: The dynamic declaration of keys. Third dimension requires
#2 keys and that needs to be on the sending and recieving end. of the #overwriting process. see $originalarray[0][0] = $firstresult[0][0];
#and if it was two dimensions it needs only one key:
# $originalarray[0] = $firstresult[0]
 
#so I guess either I have to have someway to dynamically declare array
#keys or I have to use a workaround in the function itself.