程序代码：

local function foc(n)
   -- separating occipital lobe and frontal lobe
   local SEPARATION = 163
   local ft = {}
   local c = 1
   for j = 1, n do
      for i = 1, CH do
     if i < SEPARATION then
        ft[c] = {}
        ft[c][1] = i
        ft[c][2] = j
     else
        ft[c] = {}
        ft[c][1] = i
        ft[c][2] = n + j
     end
     c = c + 1 
      end
   end
   return torch.Tensor(ft)
end