Working with Dictionaries

Dictionaries store data as key-value pairs, like a real dictionary where you look up a word (key) to find its definition (value). They're perfect for financial data where you want to associate values with meaningful labels.

Creating Dictionaries

Accessing Dictionary Values

Use keys to retrieve values:

Modifying Dictionaries

Useful Dictionary Methods

Nested Dictionaries

Dictionaries can contain other dictionaries - perfect for portfolios:

Looping Through Dictionaries

Practice: Create a Stock Dictionary

Practice: Calculate Gain/Loss

Key Takeaways

• Dictionaries store data as {key: value} pairs
• Access values with dict['key'] or dict.get('key')
• Use .get() with a default value to avoid errors
• Add/update values with dict['key'] = value
• Delete with del dict['key']
• Loop with for key, value in dict.items()
• Dictionaries can be nested for complex data structures
• Perfect for storing labeled financial data

Next, we'll put it all together and build your first financial calculator!