Help with php classes

[mpsn]

Hi, I want to build a simple calculator class and one of the function is to calculate the factorial, but for some reason I cannot get this to work.

 

Here is class:

=========

<?php
class Calculator {

function factorial($n) {
  if($n==1)
return 1;
  else 
return factorial($n-1)*$n;
}	
}//END CLASS Calculator

$calculator=new Calculator();
print $calculator->factorial(3);
?>  

 

But it doesn't work, I know this is simple but I am a little rusty with object oriented programming.

 

I'd appreciated any help!

[trq]

function factorial($n) {
  if($n==1)
return 1;
  else 
return $this->factorial($n-1)*$n;
}