gistfile1.txt

/* Import Function */ 
function is_upca($upc) 
{ 
  if (strlen((string)$upc)==12) 
	{ 
		//commence extra steps
		if (preg_match('/[a-z]/i',$upc))
		{
			return false; 
		}
		else 
		{ 
			$upc_arr = str_split($upc);
			//take last element off 
			$ld = array_pop($upc_arr);
			$od = true; //indexer to get odds
			$odds = 0; 
			$evens = 0;

			//keep in mind we only want numbers 1-11 of the array, not 1-12
			foreach ($upc_arr as $i)
			{
				if ($od = !$od) 
				{ 
					$evens += (int)$i;
							
				}
				else 
				{ 
					$odds += (int)$i;
				}					

			}
			//now we can use odds and evens to check the last digit
			//formula for check digit 
			$Mo = (($odds*3)+ $evens) % 10;
			print $Mo; 
			if ($Mo == 0) 
			{ 
				$toCheck = 0;
			}
			else 
			{ 
				$toCheck = 10- $Mo;
			}
						
			if ((int)$ld == $toCheck )
			{	
				return true;
			}
			else 
			{  
				return false;
			}
		}
				
	}
	else 
	{ 
		return false;
	}
		
}



/*End Import */