RNG generating the same number

So I was looking for a math.random function that doesn’t generate the same number after being repeated a couple of times and found this. I modified it a bit and it still generates the same number. Can anyone tell me whats wrong in this code?

function coolFunctions.generateMines(count, min, max)
	local randomNumbers = {}
	for index = 1, count do
		local randomNumber
		local nCount = 0
			randomNumber = math.random(min, max)
			nCount += 1
		until not (table.find(randomNumbers, randomNumber) and nCount == count)
		table.insert(randomNumbers, randomNumber)
	return randomNumbers

I am a bit confused about what you’re trying to achieve?

Just use math.random. It does not generate the same number, it generates random numbers.
If you want more variability in the numbers you get, you can multiply the random range by a number, and divide the result by that number:

print(math.random(1,5)) -- 1,2,3,4,5
print(math.random(10,50)/10) -- 1, 1.1, 1.2, 1.3, ..., 4.9, 5

I actually think OP wants so, that generated numbers does not get generated again.

This should do it:

local function GenerateRandomNumbers(AmountToGenerate,Min,Max)
	local RandomNumbers = {}
	for Number = 1, AmountToGenerate do
		local RandomNumber
			RandomNumber = math.random(Min,Max)
		until not table.find(RandomNumbers, RandomNumber)
		table.insert(RandomNumbers, RandomNumber)
	return RandomNumbers

Be aware that your magnitude between Min & Max, should always be equal to or greater than AmountToGenerate.

1 Like

That’s not how RNG works.


This text will be hidden

No, that is not how plain RNG works, but it will still be a random number. If you roll twice with a dice, but exclude having two of the same numbers, then both rolls will still be random - because if you roll the same number twice, then you just reroll until you get another random number. The pool of numbers are just lesser.

I think you’ve misunderstood my statement. I think OP wants to roll random numbers more than once, and make sure to always pick new numbers, that haven’t been picked before. math.random does indeed roll a random number, but if you use math.random twice with the same criterias, then there is a chance for it to roll the same number.

I don’t think that’s a bad thing since it’s still random.

Sorry Jax, but we gotta focus on what OP wants. So what you and I thinks, does not really matter. As long as OP got his/her solution. If OP needs a table filled with random numbers, but also wants to make sure that two numbers aren’t the same, then we gotta try to deliver that solution.

1 Like

If only the OP responded, then we could progress in helping him. His function to generate random (but unique) numbers is called generateMines. So, maybe he’s trying to make some sort of minefield where no mines are touching each other.

1 Like

Maybe this function will work?

local function genUniqueNumbers(amount, min, max)
	local list = {}
	while #list < amount do
		local num = math.random(min, max)
		if not table.find(list, num) then
			table.insert(list, num)
		-- Prevent crashes if you can't possibly generate new unique numbers
		if #list == abs(max - min) + 1 then break end
	return list