Lecture 2 Flashcards
What is a variable?
‘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.
What is a boolean?
False = 0 True = 1
integer + float = ?
float
integer + boolean = ?
integer
integer + string = ?
error
What function do you use to determine what variable a certain function is?
type()
What function do you use to determine the length of a list?
len()
What is the difference between a ‘list’ and an ‘array’?
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
What does % mean?
modulus
e.g. 14%10 = 4
18%6 = 0
Can you add / subtract / multiply a list with a string/integer/boolean?
No, this throws an error. You have to parse it first.
float + boolean = ?
float
float + string = ?
error
What value does len() start counting at?
len() starts at 1
What is the length of the following list?
[“Elephant”, 520, 5.0, [“Hello”, “World”]]
4
How do you determine the code of the following list? What is the output
List_1 = [5, 6.0, “hallo”, [1], [5, 3, “2”]]
print(len(List_1))
> 5
Save the words Bird, Dog, and Cat in that order to a list called Animals
Animals = [“Bird”, “Dog”, “Cat”]
How do you access items in a list?
Through indices
List_1 = [3, 6, “hi”, 7.5, [5.4], True]
How do you access the value 7.5?
print(List_1[3])
List_1 = [3, 6, “hi”, 7.5, [5, “house”], True]
How do you access the value ‘house’?
print(List_1[4][1])
How do you access the item at the end of a list?
print(List_1[len(List_1)-1]) OR print(List_1[-1])
List_1 = [3, 6, “hi”, 7.5, [5.4], True]
How do you change 7.5 to an 8?
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]
What function do you use to add items to a list?
.append()
What function do you use to add a list to a list?
.extend()
Add the value 8 to the end of List_1
List_1 = [3, 6, “hi”, 7.5, [5.4], True]
List_1.append(8)
print(List_1)
> [3, 6, “hi”, 7.5, [5.4], True, 8]
