Extra tutorials

Precision Tools System Precision Tools System: Precision Tools sells a line of high-quality woodworking tools. When customers place orders on the company’s Web site, the system checks to see if the items are in stock, issues a status message to the customer, and generates a shipping order to the warehouse, which fills the order. When the order is shipped, the customer is billed. The system also produces various reports.

(draw your context diagram)

Level-0 DFD

Modeling Logic with Decision Tables Procedure for Creating Decision Tables Name the condition and the values that each condition can assume. Name all possible actions that can occur. List all possible rules. Define the actions for each rule. Simplify the table. 2

Q1: Create a decision table- Students Campus Burglar Alarm When a burglar alarm sounds, if it is in one of students’ houses where alarm sounds every week, ignore it. Otherwise have a look outside and if the house looks not broken into and there is nobody moving inside it, ignore the alarm. Otherwise call police. List the resulting rules. Ask questions from the analyst for clarification

A1: Decision Table – Students Campus Burglar Alarm Rule Stub Rule 1 Rule 2 Rule 3 Rule 4 Condition Stub One of those houses Y N Suspicious activity Action Stub Ignore X Call Police

A1: Simplified Decision Table – Students Campus Burglar Alarm Rule Stub Rule 1 Rule 2 Rule 3 Condition Stub One of those houses Y N Suspicious activity - Action Stub Ignore X Call Police

A1: Resulting Rules- Students Campus Burglar Alarm • Rule 1: if one of those houses then ignore • Rule 2: if not one of those houses and suspicious activity then call police • Rule 3: if not one of those houses and not suspicious activity then ignore Note: rule 2 will work just as well if skip the first check: • Rule 2: if not suspicious activity then ignore