PHP array values not being changed -

i trying make program synthetic division requires factoring wrote function factor integer works, never changes values of php array $factors. any appreciated.

$factors=array(); $i; function factor($x){     if($x==0){         echo "(0,0)";         } else {             $n=false;             if($x<0) {                 $x=abs($x);                 $n=true;             }             for($i=2; $i<=$x; $i++) {                 if($x%$i==0){                     if($n){                         $factors[(count($factors))]=(-1*($x/$i));                         $factors[(count($factors))]=($i);                         $factors[(count($factors))]=($x/$i);                         $factors[(count($factors))]=(-1*$i);                     } else {                         $factors[(count($factors))]=($x/$i);                         $factors[(count($factors))]=($i);                     }                 }             }         }     } factor(-4); 

try this

function factor($x){      $factors=array();     if($x==0){         echo "(0,0)";     } else {         $n=false;         if($x<0) {             $x=abs($x);             $n=true;         }         for($i=2; $i<=$x; $i++) {             if($x%$i==0){                 if($n){                     $factors[(count($factors))]=(-1*($x/$i));                     $factors[(count($factors))]=($i);                     $factors[(count($factors))]=($x/$i);                     $factors[(count($factors))]=(-1*$i);                 } else {                     $factors[(count($factors))]=($x/$i);                     $factors[(count($factors))]=($i);                 }             }         } //end        echo '(' . implode(',', $factors). ')';     } //end if $x == 0 } factor(-4); 

$factors outside scope of function, besides not returning or outputting anything. seeing echo (0,0) assumed wanted echoed such (2,4,8) etc. can implode..