bit.lua

bit = {}
bit.uc = require("unicode")

function bit.getBits(number,length)
   local bits = {}
   local res = {}
   while true do
      local tmp = number%2
      bits[#bits+1] = tmp
      number = (number-tmp)/2
      if number == 0 then break end
   end
   if #bits < length then
      for i=#bits,length-1 do
         bits[#bits+1] = 0
      end
   end
   len = #bits
   for i=len,1,-1 do res[#res+1] = bits[i] end
   return res
end

function bit.getNumber(bits)
   local number = 0
   local count = 0
   for i=#bits,1,-1 do
      number = number+bits[i]*math.pow(2,count)
      count = count+1
   end
   return number
end

function bit.CharToBit(char,length)
   if #char > 1 then return {} end
   return bit.getBits(string.byte(char),length)
end

function bit.WordToBit(word,length)
   local bits = {}
   for i=1,#word do
      t = bit.CharToBit(string.sub(word,i,i),length)
      for q=1,#t do
         bits[#bits+1] = t[q]
      end
   end
   return bits
end

function bit.BitToWord(bits,length)
   local tmp = {}
   local word = ""
   for i=1,#bits,length do
      for q=i,i+length-1 do
         tmp[#tmp+1] = bits[q]
      end
      word = word..bit.uc.char(bit.getNumber(tmp))
      tmp = {}
   end
   return word
end

return bit