Added function to test if an integer is prime

Algorithms.lua

@@ -119,6 +119,21 @@ function getNumPrimes(numberOfPrimes)
 	return primes;
 end
 
+--This function determines whether the number passed into it is a prime
+function isPrime(possiblePrime)
+	if(possiblePrime <= 3) then
+		return possiblePrime > 1;
+	elseif(((possiblePrime % 2) == 0) or ((possiblePrime % 3) == 0)) then
+		return false;
+	end
+	for cnt = 5, math.sqrt(possiblePrime), 6 do
+		if(((possiblePrime % cnt) == 0) or ((possiblePrime % (cnt + 2)) == 0)) then
+			return false;
+		end
+	end
+	return true;
+end
+
 --This is a function that returns all the factors of goalNumber
 function getFactors(goalNumber)
 	local primes = getPrimes(math.ceil(math.sqrt(goalNumber)));	--Get all the primes up the largest possible divisor