How to random pick between 0.01% and 100%?

[Rusiteblox]

Hello! I’m doing my first game with pets and I need that random system. How should I do it?
an example:
*dog 80%
*cat 19.5%
*bird 0.5%

This is how I pick a random num, it prints 10.51, 43.35, 0.87 etc

num = (math.random(0,10000)) / 100

[Grayseon]

You wouldn’t need to divide it. Lua is not like Javascript.

[JarodOfOrbiter]

math.random returns an integer, he doesn’t want an integer. Of course, he could just make his percentages integers.

[iiNemo (nick)]

Random.new():NextNumber(0.01, 100)

[JarodOfOrbiter]

local Chances = {
    {"dog", .8},
    {"cat", .195},
    {"bird"} -- bird will be the remaining percentage, so 1 - (.8+.195) = .005. Always have exactly one value with no number
}

local function GetChance()
    local percent = math.random()
    local current = 0
    local default
    for i, v in ipairs(Chances) do
        if v[2] then
            if (v[2]+current) >= percent then
                return v[1]
            else
                current += v[2]
            end
        else
            default = v[1]
        end
     end
     return default
end

[PseudoPerson]

Correct me if I am wrong, you want a system that picks one of those values based on a percentage you get from the provided code.

Here is the code I wrote for this:

local pets = {
	["Dog"] = 25.5,
	["Cat"] = 24.5,
	["Bird"] = 50
}
local function pickAPet()
	--Picks a number
	local num = (math.random(0,10000)) / 100
	--Variable Used in Loop
	local sum = 0
	--Loop runs though the pets and their percents
	for pet, percent in pairs(pets) do
		
		--Adds the current pet's percent to the sum
		sum = sum + percent
		--If the num is less than the sum the num was in the range of the percent
		if num < sum then
			--returns the pet(in string(word) form). Ex. math.random returns a number.
			return pet
		end
	end
	--If your percents add to less than 100 there is a chance no pet will be found. Can be set to a default pet just in case(ex. "Dog") 
	return "nopet"
end
--Checks if this works(it does)
local times = 1000--must be an int
local bird = 0
local cat = 0
local dog = 0
for i = 1,times do
	local pet = pickAPet()
	if pet == "Bird" then
		bird = bird + 1
	end
	if pet == "Cat" then
		cat = cat + 1
	end
	if pet == "Dog" then
		dog = dog + 1
	end
end
print("Cat")
print(cat/(times/100))
print("Dog")
print(dog/(times/100))
print("Bird")
print(bird/(times/100))

The bottom is a check to see if it works(It’s a test I used and I thought it would be nice to have).