input_list =        [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]

Output 

 l1 [1,5,9,13]
 list 2 [2,6,10,14]
 llist 3 [3,7,11,15]
 l 4  [4,8,12,16]

How to achieve using scala

 input_list =      [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]

 l 1 = input_list[0::4]
 l 2 = input_list[1::4]
 l 3 = input_list[2::4]
 l 4 = input_list[3::4]

In python I use this code but in Scala how we done this scale

CodePudding user response：

There's no built-in operator to do this.

One way is to use zipWithIndex and filter with collect:

input
  .zipWithIndex
  .collect { case (value, index) if index % 2 == 0 => value
  }

CodePudding user response：

If your use case is only a sequence of increasing integers (perhaps with some step), there is Range:

1 to 16         // 1, 2, 3, ..., 15, 16
1 until 16      // 1, 2, 3, ..., 14, 15
1 to 17 by 2    // 1, 3, 5, ..., 15, 17
1 until 17 by 2 // 1, 3, 5, ..., 13, 15

However, you could combine that with your collection to extract values

val coll = List(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16)
(1 to 17 by 2).flatMap(coll.lift).toList