Part 2, Numbers Strings and Lists

Question 1

what is a “prototype program”

Answer 1

this is a set of smaller programs which may become part of a larger program

or a program created to get an early idea of how a program may look

Question 2

what is a “constant”

Answer 2

a constant is a variable which will not change its value during the execution of the program

Question 3

what is meant by “self documenting” code

Answer 3

this is code that almost documents itself it means it is easily readable and self explanatory for anyone reading it

appropriately named variables and modules is such an example of self documenting code

Question 4

what is meant by the term “hard coded”

Answer 4

this is a term to describe a value that appears in the code and will not change

unlike constants it will have no name and so is sometimes referred to as “magic numbers” because they make the code work but why is unclear and how it relates to the rest of the program is unclear

Question 5

instead of hard coding a value what would be a more suitable solution that maintains readability

Answer 5

creating a constant for the value would be a more suitable solution instead of hard coding

this means all occurrences of the value are easily changed and the code is “self documenting”/more readable

Question 6

what is “incremental construction”

Answer 6

this is the idea of constructing a value or variable step by step

example:
if we had to display a sentence to the user which contained variables we might construct a display_text variable adding parts of the sentence piece by piece
once built we display the display_text to the user

Question 7

what does “running step-by-step” mean

Answer 7

this involves breaking a script apart and running each block one by one. then watching how each block operates within the program

Question 8

what are four benefits of “running step-by-step”

Answer 8

1. understand what a script does
2. understand how variables change
3. understand someone else’s work
4. debugging

Question 9

what is a “list”

Answer 9

a list is a collection of data stored together as one

Question 10

name two properties that lists have

Answer 10

1. lists can shrink and grow dynamically

2. lists can store numbers, strings and more

Question 11

what are “data structures”

Answer 11

a data structure is how a programming language stores and handles data

this might include any relationships the data has or what actions may be performed on that data

Question 12

what is “persistent data”

Answer 12

persistent data is data that is held unless explicitly deleted

an example could be data in a variable which would still remain after each running of a program unless explicitly deleted

Question 13

what is a “specification”

Answer 13

a specification is description of a program giving details of what it should do

Question 14

what is an algorithm

Answer 14

an algorithm is a step by step description of your program

Question 15

creating an algorithm can be split into two distinct steps

what are they

Answer 15

1. design

2. implementation

Question 16

describe how an algorithm is designed

Answer 16

an algorithm is designed from the given specification
each step of the program should be written in detail outlining exactly how you will produce each outcome

example:
if maths is involved in the program you would describe the calculations you will be using in the algorithm

Question 17

describe how an algorithm is implemented

Answer 17

implementing an algorithm involves following each step of the algorithm and translating it into code

Question 18

what are two main reasons for creating an algorithm

Answer 18

1. creating an algorithm can help simplify some of the complexities early on
2. when a team is involved communication can be performed via the algorithm

Question 19

name two reasons an algorithm is useful within a team environment

Answer 19

1. different parts of the algorithm can be distributed to members of the team to work on so the program can be built faster
2. any problems that arise while building the program can be pointed to in the algorithm giving everyone good understanding of where or why the problem exists

Question 20

what is “acceptance testing”

Answer 20

this is a process carried out with commercial software products.

it is a set of possibly thousands of tests which are used to reassure the customer that the software behaves as it should according to its specification