Python Lists Overview

List Structure

• Lists are created by using square brackets [], and can contain any data type, including other lists, strings, numbers, and boolean values.
• Lists are indexed starting from 0 for the first element, and negative index can be used to access elements from the end.
• Individual elements in a list can be accessed using their index.
• A portion of a list can be sliced and extracted using the : slice operator.
• Lists can be concatenated using the + operator, and repeated using the * operator.
• The in operator can be used to check if an element exists within a list.

List Functions

• len(lst) returns the number of elements in a list.
• min(lst) returns the minimum element in a list.
• max(lst) returns the maximum element in a list.
• sum(lst) returns the sum of all numeric elements in a list.

Iterating on Lists

• The for loop can be used to iterate over elements in a list.
• The print function can be used to display each element in a list during iteration.

Mutable and Immutable Data Types

• Lists are mutable, meaning their contents can be modified after creation.
• String methods are immutable, and do not modify the original string.
• The remove() method modifies the list directly, removing the first occurrence of the specified element.
• The sort() method modifies the list directly, sorting it in ascending order.
• The reverse() method modifies the list directly, reversing the element order.

Warning about Results

• The sort() method modifies the list directly, and does not return a value.

String Method: split()

• The split() method splits a string into a list of substrings based on a specified delimiter.
• The default delimiter for split() is a whitespace character.

Sorting

• Only lists have an inherent sorting method.
• Other data types, if needed to be sorted, must be converted to a list.

Commas Create Tuples

• Commas can be used to create tuples, which are immutable sequences.
• Tuples can also be created using parentheses (), but parentheses are mainly for grouping rather than creating a tuple.

List Comprehension

• List comprehension is a concise syntax for constructing lists using iterations and conditional statements.
• It simplifies the creation of lists by combining iteration, filtering, and transformation operations.

Dictionaries

• Dictionaries are data structures that store key-value pairs.
• They provide a way to map a key to its corresponding value.
• Keys must be immutable data types (strings, integers, tuples), while values can be any data type.
• Dictionaries are not sequences, meaning they do not have a defined order.

Accessing Dictionary Elements

• Dictionary elements are accessed using square brackets [] and the corresponding key.
• The key acts as the index to retrieve the associated value from the dictionary.

This quiz explores the fundamental concepts of lists in Python, including list creation, indexing, and common functions. Test your understanding of how to manipulate and iterate through lists effectively.