Scala Collections Tutorial
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- Scala Collections - Quick Guide
- Scala Collections - zip
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- Scala Collections - reduce
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- Scala Collections - foldRight
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- Scala Collections - fold
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- Scala Collections - Set
- Scala Collections - Vector
- Scala Collections - ListSet
- Scala Collections - ListBuffer
- Scala Collections - List
- Scala Collections - ArrayBuffer
- Scala Collections - Array using Range
- Scala Collections - Multi-Dimensional Array
- Scala Collections - Array
- Scala Collections - Environment Setup
- Scala Collections - Overview
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Scala Collections - reduce
Scala Collections - Reduce Method
reduce() method is a member of TraversableOnce trait, it is used to collapse elements of collections. It is similar to fold method but it does not take initial value.
Syntax
The following is the syntax of reduce method.
def reduce[A1 >: A](op: (A1, A1) ? A1): A1
Here, reduce method takes associative binary operator function as a parameter. This method returns the resultant value.
Usage
Below is an example program of showing how to use fold method −
Example
object Demo {
def main(args: Array[String]) = {
val pst = List(1, 2, 3 ,4)
//apply operation to get sum of all elements of the pst
val result = pst.reduce(_ + _)
//print result
println(result)
}
}
Save the above program in Demo.scala. The following commands are used to compile and execute this program.
Command
>scalac Demo.scala >scala Demo
Output
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