Reference library

Dictionaries & sets

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

2 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 Subtract Counters in Python for Bag Differences

Use the Counter class's subtraction operator to compute bag differences, removing items and counts that appear in one multiset but not the other.

collections counter bags
Python
from collections import Counter

def subtract_counters(bag1, bag2):
    """Return the difference of two Counters (bag1 - bag2)."""
    return bag1 - bag2

if __name__ == "__main__":
    inventory = Counter(apples=10, bananas=5, oranges=3)
    sold = Counter(apples=4, bananas=2, grapes=2)
    remaining = subtract_count…
14 0 Open

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Dictionaries & sets — Python code examples

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