ab = {}
ab.need = {1,2}

x, y = 15, 37

a,b,c,d = 1,2,3,4

for i=0,6 do
      local ab={}
      ab.numb=i
      ab.learning=0
      ab.need=0
      if ab.numb==1 then
    ab.need=0
    ab.open={2}
      elseif ab.numb==2 then
    ab.need=1
    ab.open={3}
      elseif ab.numb==3 then
    ab.need=2
    ab.open={4}
      elseif ab.numb==4 then
    ab.need=3
    ab.open={4}
      elseif ab.numb==5 then
    ab.need=4
                  ab.open={6,7}
      end
      table.insert(abilities,ab)
end

for i,v in ipairs(abilities) do
   local ablt=getAbilitie(v.need)
   if v.learning==0 and ablt.learning==2  then   
    v.learning=1
   end
end

function getAbilitie(n)
   for i,v in ipairs(buttons) do
    if v.numb==n then return v end
   end   
end

attempt to index local 'ablt'(a nil value)

-- Create a 3 x 5 array
grid = {}
for i = 1, 3 do
     grid[i] = {}

     for j = 1, 5 do
         grid[i][j] = 0 -- Fill the values here
     end
end

for i=1,map.w do
     mapXY.i={}
     for j=1,map.h do
       mapXY.i.h=0
     end
end