module FDB::Tuple

def self.float_adjust(v, pos, length, encode)
  if (encode and v[pos].ord & 0x80 != 0x00) or (not encode and v[pos].ord & 0x80 == 0x00)
    v.slice(pos, length).chars.map { |b| (b.ord ^ 0xff).chr } .join
  else
    ret = v.slice(pos, length)
    ret[0] = (ret[0].ord ^ 0x80).chr
    ret
  end
end