2.1 algorithms

Question 1

define abstraction

Answer 1

the process of filtering out - essentially ignoring - the characteristics of problems that are not needed in order to concentrate on those that are needed. It is also the filtering out of specific details.

Question 2

define decomposition

Answer 2

breaking down a complex problem or system into smaller parts that are more manageable and easier to understand. The smaller parts can then be examined and solved, or designed individually, as they are simpler to work with.

Question 3

define algorithmic/computational thinking

Answer 3

It allows us to take a complex problem, understand what the problem is and develop possible solutions. These solutions can then be presented in a way that a computer, a human, or both, can understand.

Question 4

two advantages of decomposition are:

Answer 4

smaller problems are easier to understand
they can be examined in more detail

Question 5

what does this symbol indicate?

Answer 5

terminal - indicates start/end of the flowchart

Question 6

what does this symbol indicate?

Answer 6

decision - represents different yes or no decisions emerging from different points

Question 7

what does this symbol indicate?

Answer 7

process - represents a process/action

Question 8

what does this symbol indicate?

Answer 8

subroutine - used to represent a predefined process

Question 9

what does this symbol indicate?

Answer 9

flow lines - arrows used to indicate the flow of logic by connecting symbols

Question 10

define syntax error

Answer 10

This is an error in the spelling or grammar used when coding.

Question 11

define syntax

Answer 11

The set of rules that specify the correct sequence of symbols used to correctly form a structured program using specific programming language.

Question 12

define logic error

Answer 12

happen when the code does not perform according to the programmer’s intention. The program may still run without crashing, but the outcome won’t be as expected.

Question 13

define algorithm

Answer 13

A sequence of logical instructions for carrying out a task. In computing, algorithms are needed to design computer programs.

Question 14

how are trace tables useful?

Answer 14

because they enable a programmer to compare what the value of each variable should be against what a program actually produces. Where the two differ is the point in the program where a logic error has occurred.