2019 – Page 2 – Clear ur Doubt

Nov 14

Scala program to find Factorial of a given number

Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Scala program to find Factorial of a given number using Linear Recursion. Let’s look at the program:

package com.clearurdoubt

object Factorial extends App {
  def factorial(n: Int) : Int = {
    if (n == 0) 1
    else n * factorial(n-1)  // Linear Recursion
  }

  println(factorial(10))
 }

package com.clearurdoubt

object Factorial extends App {

def factorial(n: Int) : Int = {

if (n == 0) 1

else n * factorial(n-1) // Linear Recursion

}

println(factorial(10))

}

Output: Currently this program uses Linear Recursion for finding Read more

Nov 02

How to add multiple elements to a Set object in Scala

Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Scala program to add all Array elements to a Set object. We can use array.toSet() method or Set.apply() method to add all the elements of an Array Read more

Nov 01

How to remove duplicates from an Array in Scala

Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a Scala program to remove duplicates for an Array. We can achieve this by converting it to a Set object and then converting the set to array again. Read more

Oct 31

Sorting a List of custom objects using sortWith function in Scala

Hey there! Welcome to ClearUrDoubt.com. In the below post, we have seen how to sort List objects using Ordered trait. Sorting a List of custom objects using Ordered trait in Scala Today we will look at a Scala program to sort Read more

Oct 29

Array and ArrayBuffer in Scala

Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a program to demonstrate Array and ArrayBuffer objects in Scala. Scala arrays are similar to Java arrays. ArrayBuffer will provide a way to add elements at the Read more

Oct 28

Option type in Scala

Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at the Option type in Scala. Scala has a special type called “Option” to handle optional values. In programming world, sometimes a variable will have null instead of actual Read more

Oct 27

Finding word counts in a file using Spark

Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at the steps to find the word counts in a file using Spark 2.4.3. Input file:

Hey there!

Welcome to clearurdoubt.com. Happy Learning.

Hope you find these articles useful!

Happy Learning.

Hey there!

Welcome to clearurdoubt.com. Happy Learning.

Hope you find these articles useful!

Happy Learning.

Spark shell statements:

val rdd = spark.sparkContext.textFile("/clearurdoubt/test_file.txt")  // Read the input file
val words = rdd.flatMap(line => line.split(" ")).filter(word => !word.isEmpty)  // split the input lines to words and ignore the empty ones.
words.cache  // Cache the resource for future use

val totalWords = words.count  // total words in the input file

val pairs = words.map(word => (word, 1))  // parse the words into (word, noOfOccurence) pairs
val wordCounts = pairs.reduceByKey(_ + _).collect  // finding the each word count in terms of pairs and collecting them into an Array

val rdd = spark.sparkContext.textFile("/clearurdoubt/test_file.txt") // Read the input file

val words = rdd.flatMap(line => line.split(" ")).filter(word => !word.isEmpty) // split the input lines to words and ignore the empty ones.

words.cache // Cache the resource for future use

val totalWords = words.count // total words in the input file

val pairs = words.map(word => (word, 1)) // parse the words into (word, noOfOccurence) pairs

val wordCounts = pairs.reduceByKey(_ + _).collect // finding the each word count in terms of pairs and collecting them into an Array

Output:

totalWords: Long = 15

wordCounts: Array[(String, Int)] = Array((Learning.,2), (Hey,1), (Welcome,1), (Happy,2), (Hope,1), (find,1), (you,1), (there!,1), (to,1), (clearurdoubt.com.,1), (articles,1), (these,1), (useful!,1))

totalWords: Long = 15

wordCounts: Array[(String, Int)] = Array((Learning.,2), (Hey,1), (Welcome,1), (Happy,2), (Hope,1), (find,1), (you,1), (there!,1), (to,1), (clearurdoubt.com.,1), (articles,1), (these,1), (useful!,1))

Happy Learning! Please leave a reply Read more

Oct 26

Match Expression in Scala

Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a program to demonstrate the Match Expression in Scala. Match Expression is used to implement Java switch statement flow in Scala. Let’s look at the sample program:

package com.clearurdoubt

object MatchExpressionDemo {
  
  def main(args: Array[String])
  {
    matchExpression(10)
    matchExpression(10.0)
    matchExpression("10.0")
    matchExpression('C')
  }
  
  def matchExpression(ex: Any) = ex match {
    case a: Double => println(s"$a is a Double.")
    case b: Int => println(s"$b is a Integer.")
    case c: String => println(s"$c is a String.")
    case _ =>  println(s"$ex is something else.")
  }
}

package com.clearurdoubt

object MatchExpressionDemo {

def main(args: Array[String])

{

matchExpression(10)

matchExpression(10.0)

matchExpression("10.0")

matchExpression('C')

}

def matchExpression(ex: Any) = ex match {

case a: Double => println(s"$a is a Double.")

case b: Int => println(s"$b is a Integer.")

case c: String => println(s"$c is a String.")

case _ => println(s"$ex is something else.")

}

Output: Read more

Oct 25

Named and Default parameters in Scala

Hey there! Welcome to ClearUrDoubt.com. In this post, we will look at a program to demonstrate the Named and Default parameters in Scala. Named Parameters: When a function is defined, we have to pass the parameters in the same order as Read more