Module 11 - Program Design

Question 1

Why is program design important?

Answer 1

Programmers need to know what to program and how to organize their code.

Question 2

Logical vs. Physical DFDs

Answer 2

Logical: Business view, abstract.
Physical: Technical, implementation details.

Question 3

What are some steps to converting a logical DFD to a physical one?

Answer 3

1. Add implementation details
2. Draw human-machine boundaries (Dotted lines separating human external entities from the DFD).
3. Add system-related data stores, flows, and processes.

Question 4

What is fan-in and fan-out

Answer 4

Fan-in (ideal): The number of control modules that invoke a submodule

Fan-out: The number of submodules that a control module needs to control.

Question 5

A good program has:

Answer 5

1. highly cohesive modules
2. loosely coupled modules
3. high fan-in
4. low fan-out