Data Structures in Python

Up to this point, we’ve been working with what are called “primitive” data types in Python. These include integer, float, string, and Boolean.

But we can imagine scenarios where we want to be able to work with more complex data structures or more complex ways of storing and accessing information in a programming language.

In this chapter, we’re going to focus on some of the one-dimensional (or linear) data structures available to us in Python. These include strings, lists, tuples, sets, and dictionaries.

Name	Syntax	Example	Description
String	str(), ""	"Hello world!"	Sequence of characters
List	list(), []	["apple", "banana", "pear"], [1, 3, 5, 7]	Sequence of objects/values
Dictionary	dict(), {}	{'first_name': 'Knute', 'last_name':'Rockne', 'class':'1918'}	Key-value pairs
Set	set(), {}	{"apple", "banana", "pear"}, {1, 3, 5, 7}	Unordered group of unique values
Tuple	tuple(), ()	("apple", "banana", "pear"), (1, 3, 5, 7)	Ordered group of values that can include duplicates

We can use a few key questions or attributes to distinguish or compare these data structures:

• Mutability: Can values in the structure be changed once it has been created or assigned to a variable?

• Order: Does the order of values in the structure have meaning/significance, or is order not significant?

• Indexing/Slicing: Can values in the structure be accessed using their position or index? Can we isolate values in the structure using their position?

• Duplicates: Does the structure allow duplicate values?

This chapter provides an overview of foundational programming concepts in the areas of data structures and data storage, with a focus on Python syntax.

Topics covered include:

• Linear and associative arrays

• Indexing

• String objects and methods

• Lists and list methods

• Dictionaries

• Tuples

• Sets

Acknowledgements

Elements of this chapter were adapted from materials developed by:

• Dr. Peter Bui for the CSE 10101 “Elements of Computing I” course.

  • Reading 05: Lists, Strings

  • Notebook 05: Lists, Strings

  • Reading 06: Dictionaries, Sets

• Dr. Janet Davis for the the CSC 105 “The Digital Age” course.

  • Laboratory: Programming in Python

• Dr. Corey Pennycuff for the CSE 10101 Elements of Computing (Fall 2019).

• Dr. Lindsay K. Mattock for the the SLIS 5020 Computing Foundations course.

Chapter Table of Contents

• Indexing
• Strings
• Lists
• Dictionaries
• Putting It All Together
• Application
• For these last two questions, you can use any of the data structures and arguments/syntax presented in this lab. As part of your answer, include a brief explanation for why you choose a particular data structure for the task.
• Collaborative Activities
  • Python Activities
  • Microbit Activities

Application

Your answers to this chapter’s application questions should be added to the notebook template.

• Google Colab link (ND users only)

Submit the Colab link on Canvas for the assignment submission.