Functions Lesson

Prompts:

1. Write a function called add_five that takes a number and returns that number plus 5.

add_five <- function(x) {
  return(x + 5)
}  

add_five(32)

## [1] 37

2. Write a function check_number that takes a number and returns “Positive” if the number is greater than 0, “Negative” if less than 0, and “Zero” if equal to 0.

check_number <- function(x) {
  if (x > 0) {
    return("Positive")
  } else if (x < 0) {
    return("Negative")
  } else {
    return("Zero")
  }
}

check_number(5)

## [1] "Positive"

3. Write a function sum_of_cubes that uses a for loop to calculate the sum of the cubes of numbers from 1 to n.

sum_of_cubes <- function(n) {
  total <- 0
  for (i in 1:n) {
    total <- total + i^3
  }
  return(total)
}

sum_of_cubes(6)

## [1] 441

4. Write a function countdown that uses a while loop to print numbers starting from n down to 1, and then returns “Blast off!”.

countdown <- function(n) {
  while (n >= 1) {
    print(n)
    n <- n - 1
  }
  return("Blast off!")
}

countdown(12)

## [1] 12
## [1] 11
## [1] 10
## [1] 9
## [1] 8
## [1] 7
## [1] 6
## [1] 5
## [1] 4
## [1] 3
## [1] 2
## [1] 1

## [1] "Blast off!"