Dictionaries

This document covers Python dictionaries, including keys, values, creation, access, modification, deletion, and methods for managing key-value pairs efficiently.

Introduction

Dictionaries are collections in Python that store data as key-value pairs. Keys are unique and immutable, while values can be mutable or immutable.

Creating and Accessing Dictionaries

• Create a dictionary with curly brackets {}.
• Keys must be unique and immutable (often strings).
• Values can be any type and may be duplicated.

Example:

1album_release = {
2    "Back in Black": 1980,
3    "The Dark Side of the Moon": 1973,
4    "The Bodyguard": 1992
5}

Access values using keys:

1album_release["Back in Black"]  # 1980
2album_release["The Dark Side of the Moon"]  # 1973

Modifying Dictionaries

• Add a new entry: album_release["Graduation"] = 2007
• Delete an entry: del album_release["Thriller"]
• Check if a key exists: "Back in Black" in album_release (returns True or False)

Dictionary Methods

• Get all keys: album_release.keys()
• Get all values: album_release.values()

Visualizing Dictionaries

Dictionaries can be visualized as tables:

Conclusion

Python dictionaries provide a flexible way to store and manage key-value pairs. Understanding creation, access, modification, and methods is essential for efficient data handling.

FAQ