Summary Unit 4/ Chapter 17 - Abstraction and Automation notes

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S4‌‌→‌‌FUNDAMENTALS‌‌OF‌‌COMPUTATIONAL‌‌THINKING‌ ‌
C17‌‌→‌‌Abstraction‌‌and‌‌Automation‌ ‌

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Abstraction‌-‌ ‌‌reducing‌‌a‌‌problem‌‌to‌‌its‌‌essential‌‌features‌‌to‌‌help‌‌us‌‌solve‌‌the‌‌problem‌ ‌

There‌‌are‌‌6‌‌forms‌‌of‌‌abstraction:‌ ‌
1. Representational‌‌Abstraction‌ ‌
2. Abstraction‌‌by‌‌Generalization/‌‌Categorisation‌ ‌
3. Procedural‌‌Abstraction‌ ‌
4. Functional‌‌Abstraction‌ ‌
5. Data‌‌Abstraction‌ ‌
6. Problem‌‌Abstraction‌ ‌
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Representational‌‌Abstraction:‌‌ ‌
● Repeatedly‌‌removing‌‌unnecessary‌‌detail‌‌so‌‌only‌‌information‌‌needed‌‌to‌‌solve‌‌the‌‌problems‌‌
remains‌ ‌
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Abstraction‌‌by‌‌Generalisation/‌‌Categorisation:‌ ‌
● Simplifying‌‌problems‌‌by‌‌grouping‌‌characteristics‌‌together‌‌in‌‌a‌‌
hierarchical‌‌relationship‌ ‌
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Procedural‌‌Abstraction:‌ ‌

● Top-down‌‌ ‌
○ Starting‌‌at‌‌the‌‌top/‌‌beginning‌‌and‌‌breaking‌‌down‌‌problems‌‌into‌‌a‌‌series‌‌of‌‌subroutines/‌‌
procedures‌ ‌
● Focus‌‌on‌‌WHAT‌‌vs.‌‌HOW‌‌(what‌‌events‌‌trigger,‌‌their‌‌links,‌‌side‌‌effects‌‌and‌‌error‌‌handling)‌ ‌

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Functional‌‌Abstraction:‌ ‌

● The‌‌programmer‌‌designs‌‌common,‌‌re-usable‌‌functions‌‌to‌‌solve‌‌problems‌ ‌
● Reusing‌‌functions‌‌reduces‌‌complexity‌‌as‌‌they‌‌only‌‌need‌‌to‌‌be‌‌written‌‌once‌ ‌
○ Eg.‌‌for‌‌a‌‌materials‌‌management‌‌system;‌‌calctotalCost(),‌‌calcBudget()‌ ‌
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Data‌‌Abstraction:‌ ‌

● Hiding‌‌details‌‌of‌‌how‌‌data‌‌is‌‌represented‌‌so‌‌new‌‌data‌‌objects‌‌can‌‌be‌‌constructed‌‌from‌‌
previously‌‌defined‌‌data‌‌types‌ ‌
○ Eg.‌‌sentences‌‌can‌‌be‌‌abstracted‌‌into‌‌a‌‌series‌‌of‌‌words.‌‌Words‌‌can‌‌be‌‌abstracted‌‌into‌‌a‌‌
series‌‌of‌‌characters‌‌ext‌‌(where‌‌characters‌‌act‌‌as‌‌predefined‌‌data‌‌types)‌ ‌