Computational thinking Flashcards
What is abstraction?
Abstraction is removing unnecessary detail to create a more understanding and simple representation of reality
Why do we need abstraction?
Removes unnecessary complexity, saves time and resources
How much do you need to abstract?
You can add more details to make your abstraction closer to reality. If you abstract too much, your model may be too simplistic and not useful. If you abstract too little, your model will be too complex and may take up too many resources.
What is a precondition and why is it important?
A precondition is a condition that must always be true (or false) for our problem.
Why use reusable components when solving problems?
Saves us time as we don’t need to recreate.
We can import them and use them in many places. So when we want to make changes to the reusable component we only need to make that change once.
Our code will be shorter as we avoid duplication.
The reusable components would have been tested and would be reliable which would increase our code’s reliability.
Decomposition
Splits problem into sub-problems
Splits these problems further
until each smaller sub-problem can easily be solved
What is a primitive data type?
A data type provided by a programming language, e.g: real, float, integer etc.
What is a composite data type?
Composite data types are a combination of primitives and other data types. e.g: array.
What base is binary referred to?
Base 2
What base is hexadecimal referred to?
Base 16
What base is decimal/denary referred to?
Base 10
Why use hexadecimal?
- A hexadecimal value is much easier to remember than a string of binary digits.
- It is quicker to write, as hexadecimal only uses one character.
- There is a less chance of making an error when typing hex characters rather than a string of 1’s and 0’s
- It is used to define colours
- It is very easy to convert to and from binary
Each individual digit in a binary value is referred to as what?
A bit
What is a byte?
8 bits
10 to the power of what bytes is a kB, MB, GB, and TB
- kB = 10^3
- MB = 10^6
- GB = 10^9
- TB = 10^12
List the new prefixes and how many bytes they consist of
kibi KiB 2^10 bytes
mebi MiB 2^20 bytes
gibi GiB 2^30 bytes
tebi TiB 2^40 bytes
What is the purpose of normalising a floating point binary number?
Ensures the maximum accuracy for a given number of bits
Advantages of abstraction
efficiency
easy to see where to use functions
easy to identify reusable components
