Re: Generate multidimensional tables

local function tmul(ls)

local p = 1

for i, v in ipairs(ls) do p = p*v end

return p

end

function init_multi_table()

local mt = {}

local default_value = 0

local get_index = function(argls)

local t = table.remove(argls, 1)

local dt = tmul(t.dims)

local index = 1

for i, d in ipairs(t.dims) do

dt = dt / d

index = index + dt * (argls[i] - 1)

end

return t, index

end

local get = function(...) local t, i = get_index(arg); return t[i] end

local set = function(...)

local v = table.remove(arg)

local t, i = get_index(arg)

t[i] = v

end

local function create(...)

local dt = tmul(arg)

local t = {}

setmetatable(t, mt)

mt.__index = mt

t.dims = arg

for i=1,dt do t[i] = default_value end

return t

end

mt.get = get

mt.set = set

mt.create = create

return mt

end

MultiTable = init_multi_table()

mytb = MultiTable.create(3,7,5) -- create a 3-dimensional array 3x7x5

mytb:set(2,5,1, 3.14)

x = mytb:get(2,5,1) -- 3.14

x = mytb:get(3,5,1) -- 0

Francesco

2009/10/6 Michael Gerbracht <smartmails@arcor.de>

Hello Jerome,

In article <89d273ba0910060340q1b43e7e3y22afa986a4290557@mail.gmail.com">89d273ba0910060340q1b43e7e3y22afa986a4290557@mail.gmail.com>,

Jerome Vuarand <jerome.vuarand@gmail.com> wrote:
> 2009/10/6 Michael Gerbracht <smartmails@arcor.de>:
> > I would like to create a multidimensional table with a lua fuction
> > containing a predefined value[1] instead of nil which should work like
> > this:

> You can do it recursively :

> function table.dim(size, ...)
> assert(type(size)=='number')
> local lastlevel = select('#', ...)==0
> local t = {}
> for i=1,size do
> if lastlevel then
> t[i] = 0
> else
> t[i] = table.dim(...)
> end
> end
> return t
> end

Thank you very much, this looks much better!

Michael