Kursusindhold

Python Data Structures

1. Mastering Python Lists

Creating Lists in Python: Declaring and Initializing Lists List Indexing in Python: Accessing Elements Efficiently Working with Nested Lists in Python Python List Length: Measuring and Managing List Size Modifying Lists in Python: Updating and Changing Elements Using the append() Method: Adding Elements to Lists Using the insert() Method: Placing Elements at Specific Positions Deleting Elements in Python Lists: Removing Items Safely Using the remove() Method: Deleting Specific Elements from Lists

2. Mastering Python Dictionaries

Creating a Dictionary in Python: Storing Key-Value Pairs Accessing Dictionary Values Accessing Dictionary Keys Adding Items to a Dictionary: Updating Key-Value Pairs Using the del Keyword: Removing Dictionary Entries Using the pop() Method: Deleting Elements with Return Values Using the popitem() Method: Removing the Last Inserted Item Using the clear() Method: Emptying a Dictionary Completely

3. Mastering Python Tuples

Creating a Tuple in Python: Defining Immutable Data Structures Accessing Elements in a Tuple: Indexing Technique Concatenating Tuples in Python: Merging Immutable Sequences Deleting Tuples in Python: Removing References to Tuples Updating Tuples in Python Adding Items to a Tuple: Alternative Approaches Using Lists Counting Elements in a Tuple: Using the count() Method Finding Elements in a Tuple: Using the index() Method for Lookup

4. Mastering Python Sets

Creating a Set in Python: Defining Unordered Collections Using the add() Method: Adding Single Elements to a Set Using the update() Method: Merging Multiple Elements into a Set Accessing Elements in a Set: Iteration and Membership Testing Using the remove() and discard() Methods Using the clear() Method: Removing All Elements from a Set

Using the insert() Method: Placing Elements at Specific Positions

What if we want to add an item not at the end of the list, but at a specific position? For this purpose, we use the insert() method.

The syntax for the insert() method is:

python

index: the position in the list where you want to add the new element. Remember, Python uses zero-based indexing;
element: the item you want to insert into the list.

Imagine planning a trip and having a list of cities you want to visit.


              123
            
travel_wishlist = ["Paris", "Oslo", "Kyoto", "Sydney"]

print(travel_wishlist)  # Output: ['Paris', 'Oslo', 'Kyoto', 'Sydney']

This list contains four items:

However, your plans change, and you decide to adjust the order of destinations. Now, you want to prioritize "Chicago" as the first destination.


              12345
            
travel_wishlist = ["Paris", "Oslo", "Kyoto", "Sydney"]

# Adding "Rome" as the first destination
travel_wishlist.insert(0, "Chicago")
print(travel_wishlist)  # Output: ['Chicago', 'Paris', 'Oslo', 'Kyoto', 'Sydney']

After this, "Chicago" takes the 0 index. It's now at the top, and the rest of the items have shifted down. So, we now have 5 items:

Note

With the insert() function, you can add only one item at once.

Opgave

Swipe to start coding

You have the travel_wishlist list.

Prioritize two specific cities for your travels using the insert() method.

Add the "London" city as the new first destination in your list;
Then, add the "Budapest" city right after the trip to "Paris".

Løsning

Skift til skrivebord for at øve i den virkelige verdenFortsæt der, hvor du er, med en af nedenstående muligheder

Var alt klart?

Tak for dine kommentarer!

Sektion 1. Kapitel 7

Using the insert() Method: Placing Elements at Specific Positions

What if we want to add an item not at the end of the list, but at a specific position? For this purpose, we use the insert() method.

The syntax for the insert() method is:

python

index: the position in the list where you want to add the new element. Remember, Python uses zero-based indexing;
element: the item you want to insert into the list.

Imagine planning a trip and having a list of cities you want to visit.


              123
            
travel_wishlist = ["Paris", "Oslo", "Kyoto", "Sydney"]

print(travel_wishlist)  # Output: ['Paris', 'Oslo', 'Kyoto', 'Sydney']

This list contains four items:

However, your plans change, and you decide to adjust the order of destinations. Now, you want to prioritize "Chicago" as the first destination.


              12345
            
travel_wishlist = ["Paris", "Oslo", "Kyoto", "Sydney"]

# Adding "Rome" as the first destination
travel_wishlist.insert(0, "Chicago")
print(travel_wishlist)  # Output: ['Chicago', 'Paris', 'Oslo', 'Kyoto', 'Sydney']

After this, "Chicago" takes the 0 index. It's now at the top, and the rest of the items have shifted down. So, we now have 5 items:

Note

With the insert() function, you can add only one item at once.

Opgave

Swipe to start coding

You have the travel_wishlist list.

Prioritize two specific cities for your travels using the insert() method.

Add the "London" city as the new first destination in your list;
Then, add the "Budapest" city right after the trip to "Paris".

Løsning

Skift til skrivebord for at øve i den virkelige verdenFortsæt der, hvor du er, med en af nedenstående muligheder

Var alt klart?

Tak for dine kommentarer!

Sektion 1. Kapitel 7

Skift til skrivebord for at øve i den virkelige verdenFortsæt der, hvor du er, med en af nedenstående muligheder