1  Functions

Functions in R allow use a set of commands that we can keep calling repeatedly. The goal of a function is to fulfill a certain task, typically relying on inputs from a user. The rest of the problems in this short book has many functions that we ask you to write, so here, we start with some simple functions.

1.1 Questions

1. Write a function to print Hello World if user inputs 1 and Mellow World if user inputs 0

   Code

   hello_or_mellow <- function(choice)
   {
     if(choice == 1)
     {
       print("Hello World")
     }
     if(choice == 0)
     {
       print("Mellow World ")
     }
   }

   
   

2. Write a function to return Hello World if user inputs 1 and Mellow World if user inputs 0. Think about the difference between this function and that previous one.

   Code

   hello_or_mellow <- function(choice)
   {
     if(choice == 1)
     {
       return("Hello World")
     }
     if(choice == 0)
     {
       return("Mellow World ")
     }
   }

   
   

3. Consider a scenario where a garden is circular, and you need to calculate the area of the garden. Write an R function that takes the radius of the garden as input and returns the area. How would you modify this function if the garden is elliptical instead of circular?

   Code

   # Function to calculate area of a circular garden
   calculate_circular_garden_area <- function(radius) 
   {
     area <- pi * radius^2
     return(area)
   }
   
   # Function to calculate area of an elliptical garden
   calculate_elliptical_garden_area <- function(radius1, radius2) {
     area <- pi * radius1 * radius2
     return(area)
   }

   
   

4. Imagine you have two sets of exam scores, one from the first midterm and the other from the second midterm. Write an R function that takes both sets of scores as inputs and returns the set with the higher average score.

   Code

   compare_average_scores <- function(scores1, scores2) 
   {
     if (mean(scores1) > mean(scores2)) 
     {
       return(scores1)
     } else {
       return(scores2)
     }
   }

   
   

5. (Not a function question) Create two vectors vec1 and vec2, where vec1 contains 1 and Your Name while vec2 contains your JEE Advance/JAM Rank and Answer to the Question as TRUE or FALSE

   Dootika Ma’am will give all \(A\)s in this course

   Can such vec1 andvec2 be constructed? If yes, what are the datatype of 1 in vec1, and Answer to the question in vec2? Use typeof() function for finding out.

   Code

   # Define vec1 with 1 and my name
   vec1 <- c(1, "Problems")
   
   # Define vec2 with my JEE Advanced Rank (assuming rank as 10000) and the answer to the question 
   jee_rank <- 10000  # Replace this with your actual JEE Advanced Rank/ JAM Rank
   answer <- TRUE   
   
   vec2 <- c(jee_rank, answer)
   
   # Print vec1 and vec2 to verify
   vec1
   vec2
   
   # Check the datatype of 1 in vec1
   typeof(vec1[1])
   
   # Check the datatype of the boolean answer in vec2
   typeof(vec2[2])