6. Dictionaries and Sets

Objectives

In this chapter, you’ll:

• Use dictionaries to represent unordered collections of key–value pairs.
• Use sets to represent unordered collections of unique values.
• Create, initialize and refer to elements of dictionaries and sets.
• Iterate through a dictionary’s keys, values and key–value pairs.
• Add, remove and update a dictionary’s key–value pairs.

Objectives (cont.)

• Use dictionary and set comparison operators.
• Combine sets with set operators and methods.
• Use operators in and not in to determine if a dictionary contains a key or a set contains a value.
• Use the mutable set operations to modify a set’s contents.
• Use comprehensions to create dictionaries and sets quickly and conveniently.
• Learn how to build dynamic visualizations and implement more of your own in the exercises.
• Enhance your understanding of mutability and immutability.

Outline

• 6.1 Introduction
• 6.2 Dictionaries
  • 6.2.1 Creating a Dictionary
  • 6.2.2 Iterating through a Dictionary
  • 6.2.3 Basic Dictionary Operations
  • 6.2.4 Dictionary Methods keys and values
  • 6.2.5 Dictionary Comparisons
  • 6.2.6 Example: Dictionary of Student Grades
  • 6.2.7 Example: Word Counts
  • 6.2.8 Dictionary Method update
  • 6.2.9 Dictionary Comprehensions

Outline (cont.)

• 6.3 Sets
  • 6.3.1 Comparing Sets
  • 6.3.2 Mathematical Set Operations
  • 6.3.3 Mutable Set Operators and Methods
  • 6.3.4 Set Comprehensions
• 6.4 Intro to Data Science: Dynamic Visualizations
  • 6.4.1 How Dynamic Visualization Works
  • 6.4.2 Implementing a Dynamic Visualization 6.5 Wrap-Up Exercises

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