It210 Appendix E

Axia College Material

Appendix E

System-Level Requirements Example

Consider the Paint the Room program, in which you developed what are often called system-level requirements—the basis for all subsequent analysis and design steps. The following steps will take these system-level requirements and refine them into a detailed blueprint for the program.

Up to this point, you have identified the processes the program must perform, but you have not given any consideration to exactly how the processes work together to solve the problem. At this point, you must generate a description of the processing using pseudocode, a natural language description of the processing the application must perform.

The natural place to start is the system-level requirements you identified in the Input-Process-Output (IPO) chart. Determine how the processes work together: Once you have determined the top-level logic, you can then design each of the individual processes. It is this step-wise refinement process that allows you to conceptualize a vague problem into increasing levels of details in order to actually generate a working program. This point is important because the step-wise refinement pattern is used throughout the entire program development—each new piece of information is based on, and is a refinement of, the information uncovered in the previous step.

For this week’s CheckPoint, you will refine the IPO table into a complete design, as demonstrated on pp. 33 and 36 of Extended Prelude to Programming: Concepts and Design (2nd ed.). Refer also to the Input and Output Process Example in Appendix B to see how more detailed analysis and design relates to the previously constructed IPO chart.

The following information demonstrates all the items you need to develop for your programming assignments and for the final project.

Analysis

Process:

1. Get user input

2. Find room area

3. Divide room area

4. Multiply gallons

5. Prompt for ounces...