Reference library

Dictionaries & sets

Key–value maps, uniqueness, counting, grouping, and fast lookups.

4 matches
Dictionaries & sets easy

Compare Two Dictionaries in Python

Compare two dictionaries by finding common keys, unique keys, and value differences using Python's set operations.

dictionary set operations comparison
Python
def compare_data(dict1, dict2):
    """Compare two dictionaries and summarize similarities/differences."""
    keys1 = set(dict1.keys())
    keys2 = set(dict2.keys())
    
    common_keys = keys1 & keys2
    only_in_first = keys1 - keys2
    only_in_second = keys2 - keys1
    
    print(f"Common keys ({len(common_keys…
17 0 Open
Dictionaries & sets easy

How to Diff Two Dicts in Python: Added, Removed, and Changed Keys

Compare two dictionaries and report added, removed, and changed keys using Python's set operations on dict keys.

dict diff set-operations
Python
def diff_dicts(old: dict, new: dict) -> dict:
    """Compare two dicts and report added, removed, and changed keys."""
    added = {k: new[k] for k in new.keys() - old.keys()}
    removed = {k: old[k] for k in old.keys() - new.keys()}

    common_keys = old.keys() & new.keys()
    changed = {k: (old[k], new[k]) for k …
15 0 Open
Dictionaries & sets easy

How to Use Dictionaries and Sets in Python for Beginners

Demonstrates Python dictionary operations and set operations with examples, including access, modification, defaults, and set algebra.

dictionary set beginner
Python
def demonstrate_collections():
    # Dictionary basics
    student = {
        "name": "Alice",
        "age": 20,
        "courses": ["Math", "Physics"]
    }
    print("Dictionary:", student)

    # Access and modify
    student["age"] = 21
    student["grade"] = "A"
    print("Modified:", student)

    # Get with d…
11 0 Open
Dictionaries & sets easy

How to Use Dictionaries and Sets in Python for Beginners

Introduces Python dictionaries and sets with practical examples including creating, modifying, and performing set operations, plus a word-frequency counter.

dictionaries sets data structures
Python
def demonstrate_dict_sets():
    # Create a dictionary with basic info
    person = {
        "name": "Alice",
        "age": 30,
        "city": "New York"
    }
    print("Dictionary:", person)

    # Access and modify dictionary values
    person["age"] = 31
    person["email"] = "alice@example.com"
    print("Afte…
15 0 Open

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Dictionaries & sets — Python code examples

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