Python Dictionary Iteration Examples: Ready-to-Use Code

Here are practical, ready-to-use code examples for how to iterate over dictionary in Python. These snippets cover common scenarios and can be directly adapted for your projects.

Basic Dictionary Iteration #

Iterate Over Keys Only #

Iterate Over Values Only #

Iterate Over Key-Value Pairs #

Filtering During Iteration #

Filter by Value #

Filter by Key Pattern #

Sorted Iteration #

Sort by Key #

Sort by Value #

Enumerated Iteration #

With Index Counter #

Nested Dictionary Iteration #

Simple Nested Structure #

Complex Nested Structure #

Dictionary Comprehension with Iteration #

Transform Values #

Filter and Transform #

Safe Iteration with Error Handling #

Handle Missing Keys #

Check Key Existence #

Performance-Optimized Iteration #

Batch Processing #

Memory-Efficient Iteration #

Usage Tips #

When to Use Each Method #

# Use keys() when you only need keys
for key in my_dict.keys():
    process_key(key)

# Use values() when you only need values  
for value in my_dict.values():
    process_value(value)

# Use items() when you need both (most common)
for key, value in my_dict.items():
    process_key_value(key, value)

# Use enumerate() when you need index
for index, (key, value) in enumerate(my_dict.items()):
    process_with_index(index, key, value)

Common Patterns #

# Filtering pattern
filtered_dict = {k: v for k, v in my_dict.items() if condition(k, v)}

# Transformation pattern  
transformed_dict = {k: transform(v) for k, v in my_dict.items()}

# Aggregation pattern
total = sum(my_dict.values())
max_value = max(my_dict.values())
min_key = min(my_dict.keys())

# Conditional processing
for key, value in my_dict.items():
    if condition(key, value):
        process_item(key, value)

These examples show various ways to iterate over dictionary in Python. Choose the method that best fits your specific use case and data structure.

Related Examples:

• Dictionary Complete Guide
• Dictionary Iteration Tutorial
• Data Structure Helpers