Table.remove not working

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,
#1

Why isn’t it removing everything? It removes everything except for two numbers, which are 3 and 1. I don’t know why it’s not removing every number.

I know this is a short script

local script:

local Table = {5, 3, 8, 1, 4}

for i, v in Table do
	table.remove(Table, v)
end


task.wait(4)
print(table.concat(Table, " "))

prints 3 and 1

Any help is appreciated

1 Like
#2

Its because you are iterating through the table as you are attempting to clear it. The contents of the table shift down, and the shifting causes a few items to remain.

Just setting the table to {} should suffice if you are just looking to clear it entirely.

3 Likes
#3

table.remove()'s second parameter must be the index of the value you’re trying to remove. You can’t pass it the value and expect it to clean it.

local Table = {5, 3, 8, 1, 4}

for i, v in Table do
	table.remove(Table, i) -- The "i" here is the index of the value, for example for the index "1", the value would be "5".
end

print(Table) -- Should print "{}"
1 Like
#4

It prints a table with the numbers 3 and 1 like this:

[1] = 3, [2] = 1

#5

Yeah you’re right But how would I do it if I want to remove some numbers not all using another table?

#6 
for i, v in Table do 
	Table[i] = nil
end

You can replace table.remove() with this and it should work. Since table.remove() shifts the later elements, it causes that problem.

1 Like
#7

Thank you @TheRealANDRO and @1Joeb for helping me. I really appreciate it

#8

there’s a hack in programming where you can go through values in reverse, so the next indexes will remain unchanged

local Table = {5, 3, 8, 1, 4}

print(Table) -- {5, 3, 8, 1, 4}

for i = #Table, 1, -1 do
	local v = Table[i]
	if v % 2 == 0 then  -- every even number
		table.remove(Table, i)
	end
end

print(Table)  -- {5, 3, 1}
2 Likes
#9

You are using table.remove incorrectly, that’s why! It expects a list, and a list index, not a value in a list. The correct code would be this:

local Table = {5, 3, 8, 1, 4}

for i, v in Table do
	table.remove(Table, table.find(Table, v))
end

task.wait(4)
print(table.concat(Table, " "))

It seems you are using a for loop to clear a list. Why not use table.clear()? If you had other code that did something else per each item, that would make sense.

Sidenote

Here’s why your code prints {3, 1}.

local Table = {5, 3, 8, 1, 4}

for i, v in Table do
	table.remove(Table, table.find(Table, v))
end

This is going to remove index 5, then 3, then 8, etc. Here’s what the list looks like after each interation:

{(5), 3, 8, 1, 4} -- remove [5]
{5, (3), 8, 1} -- remove [3]
{5, 3, (1)} -- remove [1]
{3, 1, (nil)} -- end loop (no other item in list)
{3, 1} -- result
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#10

Just to clarify on your final part explaining the iteration of his original loop, I believe you may have made a small error. I’ve updated it so it may be a bit more clear.

{(5), 3, 8, 1, 4} -- remove 1st index: [5], table shifts to the left after the removed value
{3, (8), 1, 4} -- remove 2nd index: [8], table shifts to the left after the removed value
{3, 1, (4)} -- remove 3rd index: [4], table shifts to the left after the removed value
{3, 1, nil, (nil)} -- end loop (no other item in list)
{3, 1} -- result

Edit: I’ve misread, sorry! You were right, I incorrectly considered a:

for i, v in Table do
	table.remove(Table, i) -- i instead of v
end

Please accept my most humble of apologies :melting_face:.

1 Like
#11 
for i = #Table, 1, -1 do
	table.remove(Table, i)
end

Not sure how this is needed… You could just say Table={} or Table=nil

1 Like