Lab 2

Practice with the Design Recipe and Conds

Work excercises 34-38 in our text. Remember to use the Design Recipe and think about code reuse as you work through the exercises.

From now on, your programs should have the following sections as shown below using an example function that calculates the area of a rectangle:

• Header

; Your name, date, program name

• Signature

; Number Number -> Number  

• Purpose

; find the area of a rectangle with width w and height h

• Examples

;given

;    w = 10

;    h = 5

;expected

;    50

• Body

(define (area-rect w h)

   (* w h))

• Test

(check-expect (area-rect 10 30) 300)

Start on lab 2

1. Create a new directory for this lab in your cs101 directory by entering the following at the Linux prompt:
   1. cd
   2. cd cs101
   3. mkdir lab2
   4. cd lab2
2. To launch DrRacket, enter the following command at the Linux prompt:
   1. drracket &

Your goals today!

1. Program 2a. Work excercises 34-38 in our text. Remember to use the Design Recipe and think about code reuse as you work through the exercises.
2. Re-read the section in Part 1 about Batch Programs. After working the convert example, write Program 2b that will read a name from an input file and write it to a scene.
3. Before you submit or before you leave today, please show your code to your instructor or one of the lab coaches. Save your files!
4. You may have until midnight Saturday to finish this lab.

Log out

When you are done, close DrRacket by choosing Quit from the File menu, and then locate the logout option on the menu bar (lower right corner). Choose “Logout…” and follow any remaining prompts. Always remember to log out when you are done using the system, to ensure that no one else uses your account.