Make a Simple Calculator
Course- R Programming >
Source Code
# 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 and a switch
branching is used to execute a particular function. User-defined functions add()
, subtract()
, multiply()
and divide()
evaluate respective operations.