<?
function un_zahl($wert) {    
return ($wert % 2 == 1);} 
function a_zahl($wert) { 
   return ($wert % 2 == 0); 
} 
$array1 = array ("a"=>1,"b"=>2,"c"=>3,"d"=>5); 
$array2 = array (1, 2, 3, 4, 5, 6); 
$werte1 = array_filter($array1, "un_zahl"); 
echo "1,3,5 valores:<br>"; 
while(list($key, $val) = each($werte1)){ 
  echo $val . "<br>"; 
} 
echo "2,4,6 valores: <br>"; 
$werte2 = array_filter($array2, "a_zahl"); 
while(list($key, $val) = each($werte2)){ 
  echo $val . "<br>"; 
} 
?>