Exercises

(1) Conceptually describe the function we described in the above section, in other words

• what would be the input(s) to the function?
• what would the function return as output?
• what are the intermediate results that are created by the function?

(2) Here's a basic user-defined R function:

p <- 5
do.something <- function(n, d) {
  m <- n + p
  return(m/d)
}

• What is the name of the function?
• What are the function's arguments?
• What are the local and global variables?
• What is the "body" of the function?
• What does the function return?
• What happens to m and d (local variables) once the function finishes running?

Try to predict what the function returns in the two cases here:

do.something(10, 3)
p <- 8
do.something(10, 3)

(3) Change the above function so that p is always 5 for the function. There is more than one way to do this.