うーん。なんかリスト→Arrayが微妙… import scala.util.Random j=Random.shuffle(diff_data2.toList).toArray ランダムウォーク var tmp=0.0; var rand1=(0 to data2.length).map{b=> tmp=tmp+Random.nextGau ssian();tmp}

var tmp=a(0);a.map{b=>var c=b-tmp;tmp=b;c}.slice(1,a.length) こんな感じ scala> a res18: Array[Int] = Array(1, 2, 3, 4, 7)scala> tmp=a(0);a.map{b=>var c=b-tmp;tmp=b;c}.slice(1,a.length) tmp: Int = 7 res19: Array[Int] = Array(1, 1, 1, 3)