Course

Additional

Find the Statistical Mode Write to a File Format Decimal Places

Data Frames

Convert a List to a Dataframe Create an Empty Dataframe Combine Two Dataframe into One Change Column Name of a Dataframe Extract Columns From a Dataframe Drop Columns in a Dataframe Reorder Columns in a Dataframe Split Dataframe Merge Multiple Dataframes Delete Rows From Dataframe Make a List of Dataframes

Introduction

"Hello World" Program Add Two Vectors Find Sum, Mean and Product of Vector in R Programming Take Input From User Generate Random Number from Standard Distributions Sample from a Population Find Minimum and Maximum Sort a Vector

Strings

Concatenate Two Strings Find the Length of a String Check if Characters are Present in a String Extract n Characters From a String Replace Characters in a String Compare two Strings Convert Factors to Characters Trim Leading and Trailing Whitespaces

Vectors

Concatenate a Vector of Strings Check if a Vector Contains the Given Element Count the Number of Elements in a Vector Find Index of an Element in a Vector Access Values in a Vector Add Leading Zeros to Vector

Decision and Loops

Find the Factorial of a Number R Multiplication Table Check Prime Number check Armstrong Number Print the Fibonacci Sequence Check for Leap Year Check if a Number is Odd or Even in R Programming Check if a Number is Positive, Negative or Zero Find the Sum of Natural Numbers

Functions

Convert Decimal into Binary using Recursion in R Find the Factorial of a Number Using Recursion Find the Factors of a Number Fibonacci Sequence Using Recursion in R Find H.C.F. or G.C.D.Find L.C.M.Make a Simple Calculator Sum of Natural Numbers Using Recursion

R Program to Make a Simple Calculator

Example: Simple Calculator in R


              
# Program make a simple calculator
# that can add, subtract, multiply
# and divide using functions

add <- function(x, y) {
    return(x + y)
}

subtract <- function(x, y) {
    return(x - y)
}

multiply <- function(x, y) {
    return(x * y)
}

divide <- function(x, y) {
    return(x / y)
}

# take input from the user
print("Select operation.")
print("1.Add")
print("2.Subtract")
print("3.Multiply")
print("4.Divide")

choice = as.integer(readline(prompt="Enter choice[1/2/3/4]: "))

num1 = as.integer(readline(prompt="Enter first number: "))
num2 = as.integer(readline(prompt="Enter second number: "))

operator <- switch(choice,"+","-","*","/")
result <- switch(choice, add(num1, num2), subtract(num1, num2), multiply(num1, num2), divide(num1, num2))

print(paste(num1, operator, num2, "=", result))

Output


              
[1] "Select operation."
[1] "1.Add"
[1] "2.Subtract"
[1] "3.Multiply"
[1] "4.Divide"
Enter choice[1/2/3/4]: 4
Enter first number: 20
Enter second number: 4
[1] "20 / 4 = 5"

In this program, we ask the user to choose the desired operation. Options 1, 2, 3 and 4 are valid.

Two numbers are taken from the user and a switch branching is used to execute a particular function.

User-defined functions add(), subtract(), multiply() and divide() evaluate respective operations.