Re: Small Useful Functions
Posted: Wed May 28, 2014 9:28 am
It also might not add them in the order you want to -- if you want the values from the other table added in order, use ipairs.
LÖVE
Small Useful Functions
Page 6 of 13
Re: Small Useful Functions
Posted: Wed May 28, 2014 4:57 pm
Gotcha.
Re: Small Useful Functions
Posted: Tue Sep 30, 2014 4:50 pm
Code: Select all
requirei = local function(d, ...)
args = {...}
for k, i in ipairs(args) do
file = d .. i
require(file)
end
endRe: Small Useful Functions
Posted: Tue Sep 30, 2014 10:26 pm
Or:
,
which has the advantage of not overwriting or leaking the globals args and file. Also this doesn't contain a syntax error on the first line.
Code: Select all
local function requirei(d, ...)
for i, v in ipairs{...} do
require(d .. v)
end
endwhich has the advantage of not overwriting or leaking the globals args and file. Also this doesn't contain a syntax error on the first line.
Re: Small Useful Functions
Posted: Wed Oct 01, 2014 12:43 pm
i suppose this would be helpful as well:
Code: Select all
local function clear(t)
for i,_ in ipairs(t) do
table.remove(t, i)
end
endRe: Small Useful Functions
Posted: Wed Oct 01, 2014 1:26 pm
That function is both ineffective and inefficient: it only removes half of the items, and it takes 4 times as long for a table that's 2 times as big.
Better would be:
This removes all the items, without shuffling them around.
Better would be:
Code: Select all
local function clear(t)
for i = #t, 1, -1 do
t[i] = nil
end
endRe: Small Useful Functions
Posted: Wed Oct 01, 2014 11:53 pm
Hopefully there's nothing wrong with this one (just to keep Robin's job a little easier 
)
)
Code: Select all
local function RemoveHole( Table ) -- Removes nils from tables.
local New = {}
for Index, Value in pairs( Table ) do
New[Index] = Value
end
return New
endRe: Small Useful Functions
Posted: Thu Oct 02, 2014 6:01 am
If you remove all of the entries, then you don't even need to traverse the table backwards. This works, too:Robin wrote:Better would be:Code: Select all
local function clear(t) for i = #t, 1, -1 do t[i] = nil end end
Code: Select all
local function clear(t)
for i = 1,#t do
t[i] = nil
end
endWhat exactly should this function do? What do you mean by "remove nils values?" A variable with value "nil" does not exist. So if you have a nil-value in a table then the key-value pair does not exist. Assigning nil to a variable is a way to delete variable.davisdude wrote:Hopefully there's nothing wrong with this one (just to keep Robin's job a little easierCode: Select all
- snip -
Re: Small Useful Functions
Posted: Thu Oct 02, 2014 10:54 pm
Ya know, I'm not even sure what I was thinking when I wrote that.
Re: Small Useful Functions
Posted: Mon Oct 06, 2014 4:36 pm
Heres a few, kinda useful for tetris type games and map generating
new array
transpose array
flip array
and then rotate array
new array
Code: Select all
function newAr(h,w)
local ar = {}
for i=1,h do
ar[i] = {}
for j=1,w do
ar[i][j] = 0
end
end
return ar
end
Code: Select all
function transpose(ar)
local ar2 = newAr(#ar,#ar[1])
for i=1,#ar do
for j=1,#ar[i] do
ar2[j][i] = ar[i][j]
end
end
return ar2
end
Code: Select all
function vFlip(ar)
local ar2 = newAr(#ar,#ar[1])
for i=1,#ar do
for j=1,#ar[i] do
ar2[#ar - i + 1][j] = ar[i][j]
end
end
return ar2
end
function hFlip(ar)
local ar2 = newAr(#ar,#ar[1])
for i=1,#ar do
for j=1,#ar[i] do
ar2[i][#ar[i]-j + 1] = ar[i][j]
end
end
return ar2
end
Code: Select all
function rotLeft(ar)
return vFlip(transpose(ar))
end
function rotRight(ar)
return hFlip(transpose(ar))
end