Python Lists

Lists in Python

What is a List? A list is a collection of items that can be of any data type, including strings, integers, floats, and other lists.

Creating Lists

• Lists are created using square brackets [] and elements are separated by commas.
• Example: my_list = [1, 2, 3, 4, 5]

Indexing and Slicing

• Lists are 0-indexed, meaning the first element is at index 0.
• Negative indexing starts from the end of the list, with -1 being the last element.
• Slicing: my_list[start:stop:step] returns a subset of the list.
  • start: the starting index (inclusive)
  • stop: the ending index (exclusive)
  • step: the increment between elements (default is 1)

List Operations

• Concatenation: + operator is used to concatenate lists.
• Replication: * operator is used to replicate a list.
• Length: len() function returns the number of elements in a list.
• Append: append() method adds an element to the end of a list.
• Insert: insert() method inserts an element at a specific position.
• Remove: remove() method removes the first occurrence of an element.
• Sort: sort() method sorts a list in-place.
• Reverse: reverse() method reverses a list in-place.

List Methods

• index(): returns the index of the first occurrence of an element.
• count(): returns the number of occurrences of an element.
• extend(): adds elements from another list or iterable.
• pop(): removes and returns an element at a specific position.

Common List Functions

• min(): returns the smallest element in a list.
• max(): returns the largest element in a list.
• sum(): returns the sum of all elements in a list.
• any(): returns True if any element in a list is true.
• all(): returns True if all elements in a list are true.

Lists in Python

What is a List?

• A list is a collection of items that can be of any data type, including strings, integers, floats, and other lists.

Creating Lists

• Lists are created using square brackets [] and elements are separated by commas.
• Example: my_list = [1, 2, 3, 4, 5]

Indexing and Slicing

• Lists are 0-indexed, meaning the first element is at index 0.
• Negative indexing starts from the end of the list, with -1 being the last element.
• Slicing: my_list[start:stop:step] returns a subset of the list.
• start: the starting index (inclusive).
• stop: the ending index (exclusive).
• step: the increment between elements (default is 1).

List Operations

• Concatenation: + operator is used to concatenate lists.
• Replication: * operator is used to replicate a list.
• Length: len() function returns the number of elements in a list.
• Append: append() method adds an element to the end of a list.
• Insert: insert() method inserts an element at a specific position.
• Remove: remove() method removes the first occurrence of an element.
• Sort: sort() method sorts a list in-place.
• Reverse: reverse() method reverses a list in-place.

List Methods

• index(): returns the index of the first occurrence of an element.
• count(): returns the number of occurrences of an element.
• extend(): adds elements from another list or iterable.
• pop(): removes and returns an element at a specific position.

Common List Functions

• min(): returns the smallest element in a list.
• max(): returns the largest element in a list.
• sum(): returns the sum of all elements in a list.
• any(): returns True if any element in a list is true.
• all(): returns True if all elements in a list are true.

Learn about lists in Python, including how to create them, indexing, and slicing. Understand the basics of lists in Python programming.