arraysscalascala-collections

Trying to declare an array of a certain size in Scala

var arr = Array[Int](arr_size)
println(arr_size + " " + arr.size)

arr_size is 30 but arr.size is 1? Why is this?

I am trying to declare an empty array that I can fill in later at designated indexes.

Solution

  • Array[Int](arr_size) creates an array with one element, arr_size, and is commonly written as Array(arr_size), assuming arr_size type is Int.

    It calls apply method in the Array companion object with the signature:

    def apply(x: Int, xs: Int*): Array[Int]

    Use this instead:

    Array.ofDim[Int](arr_size)

    You could also use more functional approach and fill the array directly during initialization, e.g. by Array.tabulate.

    If you really want to call an array constructor directly, you can use:

    new Array[Int](arr_size)