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])