Purpose and Functional Requirements
Identify a software problem’s purpose and express its functional requirements as inputs, processes and outputs.
How to study National 5 Computing Science
Move from functional requirements to designs and implementation, trace data and code carefully, and support testing and evaluation with evidence.
Core concepts
Concept 1
Purpose states the overall reason the software is needed.
Exam cue: Use scenario nouns to find data and scenario verbs to find processing.
Concept 2
Inputs are data received, processes transform or use data, and outputs are produced information or actions.
Exam cue: Keep the purpose broader than one individual input or screen feature.
Concept 3
A functional requirement states behaviour the finished solution must provide.
Risk pitfalls and guardrails
Listing an implementation technique instead of a required behaviour.
Guardrail: Check option route, data type, valid boundary, loop condition, array index, identifier and expected output before committing to the response.
Confusing an output with the process used to calculate it.
Guardrail: Check option route, data type, valid boundary, loop condition, array index, identifier and expected output before committing to the response.
Memory anchors
Purpose
The overall reason the software solution is being created.
Functional requirement
A behaviour or result the finished solution must provide.
Input
Data received by the solution from a user, file or device.
Process
An operation that validates, calculates, compares or otherwise transforms data.
Output
Information or action produced by the solution.
IPO check
Every stated process should use an input or stored value and contribute to a required output.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
Why may iterative development reduce project risk?
Which phase checks actual output against an expected result?
Answer all questions to submit.
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
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