I'm new to Scala ,just started learning it today.I would like to know how to initialize an array in Scala.
Example Java code
String[] arr = { "Hello", "World" };
What is the equivalent of the above code in Scala ?
This question is related to
scala
array-initialization
If you know Array's length but you don't know its content, you can use
val length = 5
val temp = Array.ofDim[String](length)
If you want to have two dimensions array but you don't know its content, you can use
val row = 5
val column = 3
val temp = Array.ofDim[String](row, column)
Of course, you can change String to other type.
If you already know its content, you can use
val temp = Array("a", "b")
Additional to Vasil's answer: If you have the values given as a Scala collection, you can write
val list = List(1,2,3,4,5)
val arr = Array[Int](list:_*)
println(arr.mkString)
But usually the toArray method is more handy:
val list = List(1,2,3,4,5)
val arr = list.toArray
println(arr.mkString)
To initialize an array filled with zeros, you can use:
> Array.fill[Byte](5)(0)
Array(0, 0, 0, 0, 0)
This is equivalent to Java's new byte[5]
.
Can also do more dynamic inits with fill, e.g.
Array.fill(10){scala.util.Random.nextInt(5)}
==>
Array[Int] = Array(0, 1, 0, 0, 3, 2, 4, 1, 4, 3)
Another way of declaring multi-dimentional arrays:
Array.fill(4,3)("")
res3: Array[Array[String]] = Array(Array("", "", ""), Array("", "", ""),Array("", "", ""), Array("", "", ""))
Source: Stackoverflow.com