Unit 2 : Python - Introduction

Question 1

What does user see computer as?

Answer 1

1. As a set of tools ( Word Processor, Map )

Question 2

What can we do as a programmer ? （ 3 ）

Answer 2

1. Learn the programming languages
2. Use tools to build new tools ( VS Code to develop Apps )
3. Write tools to automate task

Question 3

What is a code called when it was executale?

Answer 3

1. Program

Question 4

What should we add at the end of out python file?

Answer 4

1. .py ( main.py )

Question 5

What should we do when naming variables? （ 4 ）

Answer 5

1. Create a meaningful name ( radius , practice_number )
2. Contain letters, numbers and underscore
3. Underscore can be used for multi-word variable name ( student_name )
4. Use _ when the next was letter ( num1 not num_1 )

Question 6

What should we not do when naming variable ? ( 2 )

Answer 6

1. Cannot begin with a number
2. Cannot use the keywords and the reserved words

Question 7

Is variable name case-sentive?

Answer 7

1. Yes ( radius is not the same as Radius )

Question 8

What is code?

Answer 8

1. A set of instructions that reflects human intelligence and problem-solving ability
2. Can also be seen as a form of creative expression, especially when attention is given to how users interact with the program ( UX )

Question 9

What does software allows us to do?

Answer 9

1. Package and share this intelligence with others, helping them accomplish tasks without having to solve the underlying problems themselves

Question 10

What is Interactive?
( Interactive Python )

Answer 10

1. Using the interpreter or shell, we can type in commands to get immediate results

Question 11

What is script?

Answer 11

1. Save the code into single file ( .py in python )

Question 12

What is the difference between interactive vs script ?

Answer 12

1. Interactive
   
   • You type directly to Python one line at a time and it responds
2. Script
   
   • You enter a sequence of statements (lines) into a file using a text editor and tell Python to
     execute the statements in the file

Question 13

What is constants? What are the valued stored inside constant ?

Answer 13

1. Fixed Values
2. Numbers, letters and strings

• String constants uses single-quote ( ‘ ) or double-quotes ( “ )

Question 14

What is a variable ?

Answer 14

1. A named place in the memory where a programmer can store data and later retrieve the data using the variable “name”

Question 15

When should we use assignment operator? What is the symbol of assignment operator?

Answer 15

1. When we assign a value to a variable
2. =

• It consists an expression on the right hand side and variable name to store the result

Question 16

List out the symbols in numeric expressions ( 6 )

Answer 16

3. • ( Called Asterisk )
4. /
5. ** ( Called Power )
6. % ( Called Modulus / Modulas )

Question 17

What is the noun for the term programming languges must know which expressions to do first?

Answer 17

1. Operator Precedence

Question 18

What are the rules of operator precedence rules ? From top to bottom ( 5 )

Answer 18

1. Parenthesis () is always respected
2. Exponentation ( Raise to power ** )
3. Multiplication, Division and Remainder ( * , / , % )
4. Addition and Subtraction ( + , - )
5. Left to Right

Question 19

What is the term concatenate means?

Answer 19

1. Put together

Question 20

What does python variables, literals and constants have?

Answer 20

1. Type

• type ‘str’
  type ‘int’

Question 21

How can we know the type in python?

Answer 21

e = “hello”

type(e) # shows type’str’

Question 22

List out the type of number

Answer 22

1. Integers
2. Floating Points

Question 23

What will happen when we put an integer and floating together? ( What type will get )

Answer 23

1. Float

Question 24

How can we change the type if available?

Answer 24

e = 1

e = str(e) # Use this code to change from int to str

• It will contain error when the string does not contain numeris characters

Question 25

What does the input function returns?

Answer 25

1. String

Question 26

How can we input value from python?

Answer 26

name = input(“Please enter your name : “)

print(name)

• When converting the str input to int
  age = int(input(“Age : ”))

Question 27

List out the 2 types of comments

Answer 27

1. Single-line comment ( # )
2. Multiline comment ( “”” - Start and End )

Question 28

Why should we use comments? ( 3 )

Answer 28

1. Describe what is going to happen in a sequence of code
2. Document who wrote the code or other ancillary information
3. Turn off a line of code ( perhaps temporarily )

Question 29

What is program steps ( program flow ) like ?

Answer 29

1. Like a recipe or installation instructions, a program is a sequence of
   steps to be done in order

Question 30

What are the steps? ( 3 )

Answer 30

1. Some steps are conditional - they may be skipped
2. Sometimes a step or group of steps are to be repeated
3. Sometimes we store a set of steps to be used over and over as needed in several places throughout the program