Some code need to create a sequence of numbers from some start to finish.
A Range literal is what we need.
Ranges can be defined by their start, their end, and the stepping value.
To create a range in Scala, use the predefined the method to as illustrated in the following code:
object Main {
def main(args: Array[String]) {
println(1 to 5 )
}
}
We can also create a range with the upper limit exclusive of its upper limit using the predefined method until as shown in the following code.
object Main {
def main(args: Array[String]) {
println(1 until 5 )
}
}
For 1 to 5, a Range(1,2,3,4,5) is created, but for 1 until 5 a Range with upper limit exclusive Range(1,2,3,4) is created.
We can also create a Range with stepping values using the predefined method by as shown in the following code.
object Main {
def main(args: Array[String]) {
println(1 to 20 by 4 )
}
}
The following examples show how to create ranges for the types that support them, Int, Long, Float, Double, Char, BigInt, and BigDecimal.
object Main {
def main(args: Array[String]) {
var v = 1 to 10 // Int range inclusive, interval of 1, (1 to 10)
println(v)
v = 1 until 10 // Int range exclusive, interval of 1, (1 to 9)
println(v)
val v1 = 1 to 10 by 3 // Int range inclusive, every third.
println(v1)
val v2 = 10 to 1 by -3 // Int range inclusive, every third, counting down.
println(v2)
val v3 = 1L to 10L by 3 // Long
println(v3)
val v4 = 1.1f to 10.3f by 3.1f // Float with an interval != 1
println(v4)
val v5 = 1.1f to 10.3f by 0.5f // Float with an interval < 1
println(v5)
val v6 = 1.1 to 10.3 by 3.1 // Double
println(v6)
val v7 = 'a' to 'g ' by 3 // Char
println(v7)
val v8 = BigInt(1) to BigInt(10) by 3
println(v8)
val v9 = BigDecimal(1.1) to BigDecimal(10.3) by 3.1
println(v9)
}
}
You can create ranges with an inclusive or exclusive upper bound, and you can specify an interval not equal to one: