Summary A Level OCR Computer Science (2.1 & 2.2 Notes)
7 views 0 purchase
Course
2 Algorithms and programming
Institution
OCR
Boost your exam performance with our top-notch Computer Science Revision Notes, meticulously compiled from official mark schemes of past papers. These concise, exam-focused notes cover all topics in 2.1 & 2.2 of the A Level OCR specification. Save time with clear, organized content that highlights ...
,Abstraction
Abstraction: The removal of unnecessary detail to simplify a complex
problem.
Need for abstraction:
Abstraction allows programmers to focus on core aspects of the problem and
therefore reduces programming time and complexity of the code.
It also reduces memory and processing requirements.
Difference between abstraction and reality:
Many visual elements such as trees & buildings may be removed or the quality
will be simplified as they are not relevant to the main program.
Instead it will focus on elements which are important / relevant to the program
,Thinking Ahead
Identify Inputs and Outputs:
An input can be any piece of data that an algorithm requires in order to run, usually
passed as a parameter to a subroutine.
An output can be any piece of data returned by the subroutine.
Preconditions for devising a solution:
Preconditions: Requirements that must be met before a program can run
When developing a program:
● Subroutines will need the correct data passed to them
● Input data / actions need to be validated to ensure the program works correctly
, Thinking Ahead: Caching
Caching: When frequently used data is stored so it can be accessed quickly if it's
needed again in the future.
Different parts of the problem can be stored in cache depending on the scenario.
It can speed up retrieval of data, which improves performance / reduces delays.
However, it relies on the same data being searched for, which is not always possible.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller mannshah. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.05. You're not tied to anything after your purchase.
