Dictionaries & sets
Key–value maps, uniqueness, counting, grouping, and fast lookups.
How to Count Word Frequencies in Python with Counter and Sets
This code processes a text string by lowercasing, splitting into words, counting frequencies with Counter, and extracting unique and sorted word lists using sets.
from collections import Counter
def process_text(text):
words = text.lower().split()
word_counts = Counter(words)
unique_words = set(words)
sorted_words = sorted(unique_words)
return {
"total_words": len(words),
"unique_words": len(unique_words),
"word_frequencies": di…How to Group Data by Category in Python with a Split Data Helper
This code groups a list of (category, item) pairs into a dictionary where each key is a category and each value is a list of items belonging to that category.
def split_data(categories):
"""
Group data items into buckets based on a key function.
Returns a dict where keys are bucket names and values are lists of items.
"""
buckets = {}
for category, item in categories:
if category not in buckets:
buckets[category] = []
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Dictionaries & sets — Python code examples
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