stuff 4 2morrow Flashcards
what is decomposition?
breaking down a complex problem into smaller problems
What is abstractation?
hiding or removing irrelevant details from a problem to reduce the complexity
flowchart process shape
rect
flowchart input output shape
parralelogram
flowchart decision shape
diamond
flowchart terminal shape
rounded rect
purpose of a truth table
To show all possible inputs and the dependant output
what is count controlled iteration
Count-controlled
iteration repeatedly executes a section of code a fixed number of predetermined times.
what is condition controlled iteration?
Condition-controlled
iteration
repeatedly executes a section of code until a condition is met - or no longer met.
what is pseudocode
. Instead, it is a simple way of describing a set of programming
instructions
in a manner that resembles a programming language.
advantages of pseudocode
can be easily converted to an actual programming language as it’s similar to a real language
easy to understand
syntax errors don’t matter
changes can be incorporated quite easily
disadvantages to pseudocode
can be hard to see how programs flows
takes time
describe how transistors can store a value in binary
Transistor has two states
1 represents on, 0 represents off
each stores 1 bit
Multiple transistors can store a binary value
Why is “hexadecimal uses less storage” incorrect?
- Data cannot be stored in hexadecimal // all data is
stored in binary // hexadecimal is a shortcut for
computer scientists
describe the data that is recorded when the sound is sampled
The height / amplitude…
* …as a numerical value
* …of the wave(form)
what is algorithmic thinking?
- …set out the steps needed to solve the problem //
represented in a flow chart / as pseudocode
what is input sanitisation?
cleaning up data entered by removing non standard characters
explain the purpose of testing [the vending machine]
cheks it meets user requirements
detect logic/syntax errors
check program does not crash
allow error to be fixed
so no errors when released
Give two reasons why computer scientists use hexadecimal to represent numbers instead of
binary.
less chance of input error
easy to convert between hex+binary
easier to communicate/read/remember/enter/write
What is image resolution?
number of pixels/height and width of image
what is metadata?
data about data/the file/properties of the file
why are trace tables useful?
they enable programmers to compare what the value of each variable should be against what a program actually produces.
