Percentage based Chance system

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#4

prob made a spelling mistake which made it like that
in game it works perfectly fine
(i rewrote the code while making the post, sorry about the inconsistency)

#5

ok no problem does the new code work better

#6

yes but like i said its not percentage based, when i change the value of uncommon the common’s chance changes with it

#7

ok the problem i mentioned before is that its poorly structured when calculating the percentage

#8

Try using Random.new() instead of math.random()

#9

doesnt Random.new():NextNumber(0,100) do the exact same thing as math.random() * 100

#10

oh yeah my bad i was looking at your code it does the same thing. but the way i would rewrite your code would be different

#11

But then again your right would have to change the rarities to increase chances as if one goes up the other one too.Or you can add a range between chances to prevent common rarity changing.

#12

also the things you’re mentioning have nothing to do with the problem im mentioning

the for i,v in pairs() part of the code checks if v is below or equal to random
assuming that v is 100 (common) it would have a 50% chance of it being picked beacuse if random returns 50 then uncommon would be picked
which means that if random is a number between 100 and 50 it will select common (50%)
if its a number between 50 and 20 it will be uncommon (30%)
if its a number between 20 and 10 it will be rare (10%)
if its a number between 10 and 3 it will be epic (7%)
if the number is below 3 or equal to 3 then it will be legendary

i hope now you understand how the code works

the thing im asking is how can i decrease the uncommons max chance value without accidentally increasing common’s chance

#13

This is more what you’re looking for…

local Chances = {{"Legendary", 1}, {"Epic", 5}, {"Rare", 20}, {"Uncommon", 30}, {"Common", 100}}

while true do
	for _, v in ipairs(Chances) do
		--math.randomseed(tick())
		if math.random(1, 100) <= v[2] then
			print(v[1])
			break
		end
	end	task.wait(1)
end
1 Like
#14

wait but doesnt the math.random constantly change which means there is a small chance of it returning nothing?

#15

No it will always be 1 - 100… A little different way of doing it here along with a drastic difference in the number set up. This approach is to generate a weighted table based on absolute values rather than cumulative probabilities.

#16

wait i was writing the message to debunk your code saying theres a small chance of it returning nothing but im wrong, i think you created the PERFECT percentage based chance system

1 Like
#18

this is good, but i recommend using a weighted chance system for more accuracy

here’s a tutorial i found here on the devforum

#19

i found a few problems with weighted chance system hence why i didnt use it

#20

what problems though, im curious

#21

actually now that i think about it doesnt have problems i just saw something i didnt see earlier

still not gonna use it cuz i like writing my own code and also the weighted chance system is much longer

#22

wait is it this? im sorry but idk what “changing values” ur referring to. do u mean changing the value in the table? or is it about creating other variables?

#23

its up to your choice anyways, its just that jay’s code seems like rarer changes might get (a little) more common than common, unlike the weight chance system which acts like a spinning wheel

still its up to ur choice

#24

this message right here is about changing the values

this problem is fixed on the solution post