When we are working with R in an interactive session, we can use readline() function to take input from the user (terminal).
This function will return a single element character vector.
So, if we want numbers, we need to do appropriate conversions.
Example: Take input from user
my.name <- readline(prompt="Enter name: ")
my.age <- readline(prompt="Enter age: ")
# convert character into integer
my.age <- as.integer(my.age)
print(paste("Hi,", my.name, "next year you will be", my.age+1, "years old."))
Output
Enter name: Mary Enter age: 17 [1] "Hi, Mary next year you will be 18 years old."
Here, we see that with the prompt argument we can choose to display an appropriate message for the user.
In the above example, we convert the input age, which is a character vector into integer using the function as.integer().
This is necessary for the purpose of doing further calculations.