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✓ ANSWER ACCEPTED

How to randomize a dictionary?

Asked 459 views1 answers

I am using a dictionary because I am using the keys in the dictionary so that I know a certain dialogue option corresponds to a type of item. I want to have the VALUES (NOT THE KEYS) of the array/dictionary to be picked at random but I keep getting an error saying " 'random' (interval is empty) "

Here is my code

local initialPrompts = {
	["osv"] = "Hello there, one scoop of vanilla please.",
	["osv"] = "Let me have one scoop of vanilla ice cream.",
	["osc"] = "I'd like one scoop of chocolate ice cream."
}
local choicePrompts = {"Thanks", "Thank You", "Have a nice day", "Enjoy your day"}
local dialog = script.Parent.Brain.Dialog
local iceCreamChoice = script.Parent.icecreamchoice
enabled = true

if enabled == true then
	enabled = false	
		math.randomseed(tick())
		local chosenInitialPrompt = initialPrompts[math.random(1,#initialPrompts)]
		print(chosenInitialPrompt)
	
	
	enabled = true
end
AnonymousEdited

1 comment

0

'math.random(a, b)' will throw that error if there is no integer between the range 'a-b', where both 'a' and 'b' are inclusive. By the way, you can omit '1' if you want 'math.random' to give a random value between '1' and some other number.

Anonymous#

1 answer

✓ Accepted answer

Careful: what you have written is not a valid dictionary. You cannot repeat keys. Lua will pick either the first "osv" or the secodn "osv" and use just one.

You can't use # on a dictionary. # tells how to find numeric indices, 1, 2, 3, ..., #list. But a dictionary has nothing at those indices.

Since math.random returns a number, you're not going to find anything if you try initialPrompts[math.random(...)] anyway.

The only random functionality in Lua is math.random() which is used to produce numbers.

A straightforward way to use math.random to get something other than numbers is to pick objects by their (numeric) index in a list:

function chooseFromList(list)
	return list[math.random(#list)]
end

A dictionary is not a list. But from a dictionary we can make lists. We could make a list of the keys, pick a random key, then get the value at that key. Or we could just make a list of values, and pick a value.

local keys = {}

for key in pairs(dictionary) do
	table.insert(keys, key)
end

local randomKey = chooseFromList(keys)

local randomValue = dictionary[randomKey]
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