Getting the highest indexed value in a table

Hello everybody!

While working on my tower defense game I ran into a problem with tables:
To find the farthest enemy on the track I use waypoint numbers and the enemies’ distances to them to get a table somewhat that has:

  • As the index, the distance between the enemy and the next waypoint
  • As the value, the object value of said enemy

For example:

local distances = {
    [5.12] = --Normal enemy,
    [2.41] = --Speedy enemy,
    [4.23] = --Boss,

and so on.

My question is, is there any way I can retrieve the value with the highest index number in the array (In this case, the normal enemy)?

1 Like

I’d suggest moving away from floating-point indexes, anything that’s not an integer, string or Instance in a table can get messy and weird.

If you really wanna store both the distance and object, consider the format {distance, object} then a simple loop to go through every element to get the highest distance.
Another solution is having two tables, one being [number] = distance then another being [object] = number where the number value in the objects table links to the index of the distance, so finding the distance from the enemy would be Distance[Objects[object]].

If you really wanna stick with this though, here’s a simple bit of code to get the highest distance.

local index
for distance, _ in distances do
    if not index or distance > index then
        index = distance

print(string.format("The farthest (%i studs away) mob is %s", index, distances[index].Name))

EDIT: In my personal opinion you shouldn’t store the distance at all, calculating distance is very fast and very easy so whenever you actually need to get the highest distance, having a table of all the mobs would be much easier to manage and if anyone were to look at your code (including yourself) it’d be much easier to understand.

1 Like

Use table.sort() and get the first value :slight_smile:


This is too vague. His structure won’t work with table.sort because it gives the values of the table, not the indexes.

This’ll work but also, I don’t understand storing distances in a table unless you’re doing this every frame? It just doesn’t make sense.

you dont need to use dummy variables for tuples if your not going to access the next value ex:

for d in distances do
1 Like

here, I made a quick script.

local distances = {
	[5.12] = "Normal enemy",
	[2.41] = "Speedy enemy",
	[4.23] = "Boss",

local function _get(highest)
	local wantedIndex = -math.huge

	table.foreach(distances, function(a, _)
		table.foreach(distances, function(b, _)
			wantedIndex = highest and a > b and a > wantedIndex and a or b > wantedIndex and b or wantedIndex

	return wantedIndex


I have no idea why I didn’t think about storing things in a {distance, object} kind of fashion, thanks a lot! I’ll be trying out that script first as changing the table structure would mean changing a lot of other code, but I’ll definitely switch to your first solution later. Thanks again!