View difference between Paste ID: uwGhstyk and bGf8UKr8

 // convert a byte into a list of ones and zeros
 
 def bits(num: Int): List[Int] = (for (i <- Range(0,8)) yield (((num << i) & 0xff) >>> 7)).toList
 
 // given a list, take the first N bits
 
 def next(bits: List[Int], numBits: Int) = {
 
   val filler = List[Int](8 - numBits) map (_ => 0)
   val bitList = filler ++ bits.take(numBits)
 
   def convert (accumulator: Int, val_pos: Tuple2[Int, Int]) =
     accumulator + (val_pos._1 << val_pos._2)
 
   bitList.reverse.zipWithIndex.foldLeft(0) { convert }
 }
 
 def localStrings(len: Int, data: DataInputStream): List[String] = {
 
   // Works for the NDFD data files as I've found them, but doesn't
   // account for more than one group of data (say), or bits that
   // might be stored as floating point numbers.
 
   val numGroups = readInteger(2, data)
   val numValues = readInteger(4, data)
   val refValue  = data.readFloat()
   val scale     = readInteger(2, data)
   val recScale10 = 1 / math.pow(10, scale)
   val numBits    = data.readUnsignedByte()
   val dataType   = data.readUnsignedByte()
 
   // TODO: This really needs to be "streamed" in some
   // way so we don't have to keep such a massive list
   // in memory. Okay for local WX strings, but is
   // unusable on huge CONUS data sets.
 
   // Convert the data into a list of ones and zeros
 
   var packed: List[Int] = List()
 
   for (i <- 1 to (len - 14))
     packed = packed ++ bits(data.readUnsignedByte)
 
   // Expand the packed bit list into bytes
 
   var unpacked: List[Char] = List()
 
   for (i <- 1 to numValues) {
     unpacked = unpacked ++ List(((refValue + next(packed, numBits)) * recScale10).toChar)
     packed = packed.drop(numBits)
   }
 
   // Convert the zero-delimited strings into a list of strings
 
   unpacked.mkString.split(0.toChar.toString).toList
 }