Lecture 2

Question 1

What is a variable?

Answer 1

‘a store of value’. variables can be seen as nametags, as they refer to values. They are not the values the refer to though.

e.g. a = 5
in here, the variable ‘a’ refers to the value 5.

Question 2

What is a boolean?

Answer 2

False = 0 
True = 1

Question 3

integer + float = ?

Answer 3

float

Question 4

integer + boolean = ?

Answer 4

integer

Question 5

integer + string = ?

Answer 5

error

Question 6

What function do you use to determine what variable a certain function is?

Answer 6

type()

Question 7

What function do you use to determine the length of a list?

Answer 7

len()

Question 8

What is the difference between a ‘list’ and an ‘array’?

Answer 8

list = variable type that consists of other variables
–> you can mix variable types within a list

array = variable type that consists of type specific lists

Question 9

What does % mean?

Answer 9

modulus

e.g. 14%10 = 4
18%6 = 0

Question 10

Can you add / subtract / multiply a list with a string/integer/boolean?

Answer 10

No, this throws an error. You have to parse it first.

Question 11

float + boolean = ?

Answer 11

float

Question 12

float + string = ?

Answer 12

error

Question 13

What value does len() start counting at?

Answer 13

len() starts at 1

Question 14

What is the length of the following list?

[“Elephant”, 520, 5.0, [“Hello”, “World”]]

Answer 14

4

Question 15

How do you determine the code of the following list? What is the output

List_1 = [5, 6.0, “hallo”, [1], [5, 3, “2”]]

Answer 15

print(len(List_1))

> 5

Question 16

Save the words Bird, Dog, and Cat in that order to a list called Animals

Answer 16

Animals = [“Bird”, “Dog”, “Cat”]

Question 17

How do you access items in a list?

Answer 17

Through indices

Question 18

List_1 = [3, 6, “hi”, 7.5, [5.4], True]

How do you access the value 7.5?

Answer 18

print(List_1[3])

Question 19

List_1 = [3, 6, “hi”, 7.5, [5, “house”], True]

How do you access the value ‘house’?

Answer 19

print(List_1[4][1])

Question 20

How do you access the item at the end of a list?

Answer 20

print(List_1[len(List_1)-1])
OR
print(List_1[-1])

Question 21

List_1 = [3, 6, “hi”, 7.5, [5.4], True]

How do you change 7.5 to an 8?

Answer 21

You got to select the INDEX of the value you want to change and assign it a new value.

Example:
List_1 = [3, 6, "hi", 7.5, [5.4], True]
List_1[3] = 8
print(List_1)
> [3, 6, 'hi', 8, [5.4], True]

Question 22

What function do you use to add items to a list?

Answer 22

.append()

Question 23

What function do you use to add a list to a list?

Answer 23

.extend()

Question 24

Add the value 8 to the end of List_1

List_1 = [3, 6, “hi”, 7.5, [5.4], True]

Answer 24

List_1.append(8)
print(List_1)
> [3, 6, “hi”, 7.5, [5.4], True, 8]