i am tying to fit a function inside an array, but this doesn't seem to be working. do i ave to enclose the function inside anything if its inside an array? thanks

$plates = array ("1","2","3","4","5","6","7","8","9","10 ","11","12","13","14","15","16","17","18 ","19");
foreach ($plates as $plate)
{
plt($plate,$s1,$s3,$s4,$s5);
$sp = " ";
echo $ss2.$sp.$poo;
if ($poo != "")
{
$sp = " ";
echo $ss2.$sp.$poo;
}
else
{
echo "no";

}

the variables that arent explained are global variables set in the function