toQuadList.scala

def toQuadList()= {
   def lrQuadsFromLine(line: List[Int], accumulator: List[List[Int]]): List[List[Int]] = {
        if (line.length < 4)
          accumulator
        else
          lrQuadsFromLine(line.tail, accumulator :+ line.slice(0, 4))
    }
    data.flatMap(line => lrQuadsFromLine(line, List.empty))
}