1. Learning Intention
I will learn about the iterative software development process with a focus on the Design stage.

2. Analysis
Design
Implementation
Testing
Documentation
Evaluation

3. Design Notations 3 design notations: Pseudocode Structure Diagram
Flow charts
Focus today on Structure Diagrams

4. DESIGN - Structure Diagram
Graphical representation of the steps to solve a problem.
Structure diagrams must be read from the top down and from left to right.

5. Structure Diagram
4 types of notation used to represent the workings of the program:
Pre-defined process
Selection /
Decision
Process
Loop

6. PROBLEM: show average of 3 numbers
e.g. Average 3 numbers
PROBLEM: show average of 3 numbers
Get number
Add number to total
Repeat 3 times
Calculate average
Display average

7. PROBLEM: calculate postage RECEIVE weight of parcel
SEND Cost = £4.50 TO DISPLAY
RECEIVE weight of parcel
Parcel over 200g?
SEND Cost = £1.50 TO DISPLAY
YES NO
Parcel over 100g?
SEND Cost = £2.50 TO DISPLAY
e.g. Calculate Postage

8. Create structure diagrams for the following problems:
Is the user old enough to drive?
Calculating the cost of 5 items of shopping.

9. Are you old enough to drive?
PROBLEM: old enough to drive
RECEIVE age FROM KEYBOARD
Age 17 or more?
YES
SEND “you can drive” TO DISPLAY
SEND “too young” TO DISPLAY NO

10. PROBLEM: calculate cost of 5 shopping items
Calculating the cost of 5 items of shopping
PROBLEM: calculate cost of 5 shopping items
Repeat 5 times
DISPLAY total
RECEIVE item_cost FROM KEYBOARD
ADD item_cost TO total

11. Worksheet
In your jotter, complete the 3 Structure Diagram questions from the Graphical Design Notations worksheet.

12. Success Criteria
I can use structure diagrams to design a solution to a problem.