Reference library

Dictionaries & sets

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

3 matches

How to Normalize Data in Python with Dictionaries and Sets

Normalize a list of dicts by keeping selected keys, stripping/lowercasing strings, and extracting unique sorted values using set comprehension.

dictionaries sets data-cleaning

Python

def normalize_data(data, keys):
    """
    Normalize a list of dictionaries by keeping only specified keys
    and converting values to proper types.
    """
    normalized = []
    for item in data:
        clean_item = {}
        for key in keys:
            value = item.get(key)
            if isinstance(value, st…

12 0 Open

Dictionaries & sets easy

How to Parse Data Into Dictionaries and Sets in Python

Parses raw student strings into a dictionary of lists and finds unique courses using a set.

dictionary set defaultdict

Python

from collections import defaultdict

def parse_students(raw_data):
    """Parse raw student strings into a dictionary of lists."""
    parsed = defaultdict(list)
    for entry in raw_data:
        name, _, course = entry.partition(":")
        parsed[course.strip()].append(name.strip())
    return dict(parsed)

def fi…

12 0 Open

Dictionaries & sets easy

How to convert string values to int or float in Python dicts

Recursively convert string values in nested dicts and lists to ints or floats when possible, leaving other strings untouched.

dict type-conversion recursion

Python

def coerce_str_values(data):
    """Recursively convert string values that look like ints or floats."""
    if isinstance(data, dict):
        return {key: coerce_str_values(val) for key, val in data.items()}
    elif isinstance(data, list):
        return [coerce_str_values(item) for item in data]
    elif isinstance…

12 0 Open

Browse by section

Each section groups closely related Python snippets.