Lua-从文本文件解析并存储不同长度的值

Question

I am a beginner in programming with Lua, and I am stuck with reading a text file and trying to store this in an array. I know there already exists a topic like this, but I was wondering how I should store lines with different amount of numbers. eg: in the textfile:

1 5 6 7
2 3
2 9 8 1 4 2 4

How do I make an array from this? The only solutions I find are with identical amount of numbers.

Answer 1

local tt = {}
for line in io.lines(filename) do
   local t = {}
   for num in line:gmatch'[-.%d]+' do
      table.insert(t, tonumber(num))
   end
   if #t > 0 then
      table.insert(tt, t)
   end
end

Answer 2

Supposing you want the resulting lua-table (not array) to look like:

mytable = { 1, 5, 6, 7, 2, 3, 2, 9, 8, 1, 4, 2, 4 }

then you'd do:

local t, fHandle = {}, io.open( "filename", "r+" )
for line in fHandle:read("*l") do
    line:gmatch( "(%S+)", function(x) table.insert( t, x ) end )
end

Answer 3

You could parse the file character by character. When a char is a number, add it to a buffer string. When it's a space, add the buffer string to an array, and convert it to a number. If it's a newline, do the same as with a space, but also switch to the next array.

Answer 4

t = {}
index = 1
for line in io.lines('file.txt') do 
    t[index] = {}
    for match in string.gmatch(line,"%d+") do 
        t[index][ #t[index] + 1 ] = tonumber(match)
    end 
    index = index + 1
end 

You can see the output by doing

for _,row in ipairs(t) do
    print("{"..table.concat(row,',').."}")
end 

Which shows

{1,5,6,7}
{2,3}
{2,9,8,1,4,2,4}