Scala Tutorial Scan Function Example

Scan operation accepts the binary operation as boundary and returns the incentive for every component in collections for that activity. It returns every cycle for that twofold administrator in the collections. In scan additionally we can characterize the underlying worth.

he scan function in Scala is a powerful method used to perform cumulative operations on a collection, producing intermediate results at each step. It is similar to the foldLeft or foldRight functions but differs in that it returns a collection of all intermediate results, including the final result.

The scan function takes an initial value and a binary operator as parameters. It applies the binary operator sequentially to each element of the collection, starting with the initial value. 

The scan function is useful for generating cumulative results, exploring intermediate states of computation, and implementing dynamic programming algorithms efficiently. Understanding how to use scan effectively is essential for mastering functional programming concepts in Scala. Scala Tutorial Scan Function Example

use case 1:

In addition to its practical applications, understanding the scan function contributes to a deeper grasp of functional programming concepts in Scala, such as immutability, higher-order functions, and the use of combinators to transform data. By exploring examples and experimenting with the scan function, developers can gain insights into how functional programming techniques can be leveraged to solve complex problems concisely and elegantly in Scala. This introduction sets the stage for exploring practical examples and applications of the scan function, demonstrating its versatility and utility in data processing and algorithm design.

// Scala program sum of elements 
// using scan function 
// Creating object
object prwatech {
// Main method
    def main(arg:Array[String])
    {
        //initialize a sequence of numbers
        val numbers: Seq[Int] = Seq(3, 2, 1)
        println(s"Elements of numbers = $numbers")
  
        //find the sum of the elements using scan function
        val iterations: Seq[Int] = numbers.scan(0)(_ + _)
        println("Running total of all elements" + s"in the collection = $iterations")
    }
}

output:

Elements of numbers = List(3, 2, 1)
Running total of all elementsin the collection = List(0, 3, 5, 6)

use case 2:

// Scala program concatenate string 
// using scan function 
// Creating object
object prwatech {
// Main method
    def main(arg:Array[String])
    {
        // initialize a sequence of strings
        val str_elements : Seq[String] = Seq("hello", "Prwa", "Tech", "Bangalore")
        println(s"Elements = $str_elements")
  
        // Concatenate strings with scan function
        val concat : Seq[String]
                    = str_elements.scan("")((a, b) => a + "-" + b)
        println(s"After concatenation = $concat")
    }
}

output:

Elements = List(hello, Prwa, Tech, Bangalore)
After concatenation = List(, -hello, -hello-Prwa, -hello-Prwa-Tech, -hello-Prwa-Tech-Bangalore)

use case 3:

object prwatech {
// Main method
  def main(arg:Array[String])
    {
        // initialize a sequence of elements
        val seq_elements: Seq[Double] = Seq(0.5, 5.0, 1)
        println(s"Elements = $seq_elements") 
  
        // find the multiplication of the elements
        // using reduce function
        val sum: Double = seq_elements.reduce((a, b) => a * b)
        println(s"multiplicaion of elements = $sum")
    }   
}

output:

Elements = List(0.5, 5.0, 1.0)
multiplicaion of elements = 2.5