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Python Data Structures
course content

Course Content

Python Data Structures

Python Data Structures

1. List
Creating a ListNested ListChallenge: Create a ListList IndexingList LengthLists are MutableAppend() MethodInsert() MethodDeleting ElementsRemoving ElementsList Comprehensions
2. Dictionary
Creating a DictionaryChallenge: Craft the DictionaryExtraction of InformationAdding ItemsDel KeywordPop() MethodPopitem() MethodClear() MethodDictionary Comprehensions
3. Tuple
Creating a Tuple Accessing Elements of a TupleConcatenation of Tuples Delete a Tuple Update a TupleAdding Items Challenge: Concatenate Tuples
4. Set
Creating a SetAdd() MethodUpdate() MethodAccessing the Elements of a SetRemove() and Discard() MethodsClear() Method
5. For deleting
Test grid chapterTest 2

bookList Indexing

In Python, lists allow for element indexing. This means we can access each item in the list by its index. Remember, indexing in lists starts at 0. So, the first item is at index 0, the second at index 1, and so forth.


              
1234567

            
list_A = ['red', 'green', 'blue', 'yellow', 'black']

# Getting the first element
print(list_A[0])

# Getting the third element
print(list_A[2])
copy

We've covered positive indexing, but there's also something called negative indexing. Negative indexing starts from the end of the list. For instance, index -1 refers to the last item, index -2 points to the second-to-last item, and so on.


              
1234567

            
list_A = ['red', 'green', 'blue', 'yellow', 'black']

# Getting the last element
print(list_A[-1])

# Getting the fourth element
print(list_A[3], list_A[-2])
copy

Let's put this into practice.

Task

You're given: list_1 = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h']. Your task is to extract the first, third, fifth, and seventh items from this list and create a new list with these items, using positive indices only.

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Section 1. Chapter 4
toggle bottom row

bookList Indexing

In Python, lists allow for element indexing. This means we can access each item in the list by its index. Remember, indexing in lists starts at 0. So, the first item is at index 0, the second at index 1, and so forth.


              
1234567

            
list_A = ['red', 'green', 'blue', 'yellow', 'black']

# Getting the first element
print(list_A[0])

# Getting the third element
print(list_A[2])
copy

We've covered positive indexing, but there's also something called negative indexing. Negative indexing starts from the end of the list. For instance, index -1 refers to the last item, index -2 points to the second-to-last item, and so on.


              
1234567

            
list_A = ['red', 'green', 'blue', 'yellow', 'black']

# Getting the last element
print(list_A[-1])

# Getting the fourth element
print(list_A[3], list_A[-2])
copy

Let's put this into practice.

Task

You're given: list_1 = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h']. Your task is to extract the first, third, fifth, and seventh items from this list and create a new list with these items, using positive indices only.

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Everything was clear?

How can we improve it?

Thanks for your feedback!

Section 1. Chapter 4
toggle bottom row

bookList Indexing

In Python, lists allow for element indexing. This means we can access each item in the list by its index. Remember, indexing in lists starts at 0. So, the first item is at index 0, the second at index 1, and so forth.


              
1234567

            
list_A = ['red', 'green', 'blue', 'yellow', 'black']

# Getting the first element
print(list_A[0])

# Getting the third element
print(list_A[2])
copy

We've covered positive indexing, but there's also something called negative indexing. Negative indexing starts from the end of the list. For instance, index -1 refers to the last item, index -2 points to the second-to-last item, and so on.


              
1234567

            
list_A = ['red', 'green', 'blue', 'yellow', 'black']

# Getting the last element
print(list_A[-1])

# Getting the fourth element
print(list_A[3], list_A[-2])
copy

Let's put this into practice.

Task

You're given: list_1 = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h']. Your task is to extract the first, third, fifth, and seventh items from this list and create a new list with these items, using positive indices only.

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Everything was clear?

How can we improve it?

Thanks for your feedback!

In Python, lists allow for element indexing. This means we can access each item in the list by its index. Remember, indexing in lists starts at 0. So, the first item is at index 0, the second at index 1, and so forth.


              
1234567

            
list_A = ['red', 'green', 'blue', 'yellow', 'black']

# Getting the first element
print(list_A[0])

# Getting the third element
print(list_A[2])
copy

We've covered positive indexing, but there's also something called negative indexing. Negative indexing starts from the end of the list. For instance, index -1 refers to the last item, index -2 points to the second-to-last item, and so on.


              
1234567

            
list_A = ['red', 'green', 'blue', 'yellow', 'black']

# Getting the last element
print(list_A[-1])

# Getting the fourth element
print(list_A[3], list_A[-2])
copy

Let's put this into practice.

Task

You're given: list_1 = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h']. Your task is to extract the first, third, fifth, and seventh items from this list and create a new list with these items, using positive indices only.

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Section 1. Chapter 4
Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
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