Preface xi Chapter 1 Introduction to Computers and Programming 1 1.1 Introduction 1 1.2 Hardware and Software 2 1.3 How Computers Store Data 8 1.4 How a Program Works 13 1.5 Using Python 20 Chapter 2 Input, Processing, and Output 31 2.1 Designing a Program 31 2.2 Input, Processing, and Output 35 2.3 Displaying Output with the print Function 36 2.4 Comments 39 2.5 Variables 40 2.6 Reading Input from the Keyboard 49 2.7 Performing Calculations 53 2.8 More About Data Output 65 Chapter 3 Simple Functions 81 3.1 Introduction to Functions 81 3.2 Defining and Calling a Function 83 3.3 Designing a Program to Use Functions 89 3.4 Local Variables 95 3.5 Passing Arguments to Functions 97 3.6 Global Variables and Global Constants 107 Chapter 4 Decision Structures and Boolean Logic 117 4.1 The if Statement 117 4.2 The if-else Statement 125 4.3 Comparing Strings 130 4.4 Nested Decision Structures and the if-elif-else Statement 134 4.5 Logical Operators 142 4.6 Boolean Variables 149 Chapter 5 Repetition Structures 157 5.1 Introduction to Repetition Structures 157 5.2 The while Loop: a Condition-Controlled Loop 158 5.3 The for Loop: a Count-Controlled Loop 167 5.4 Calculating a Running Total 179 5.5 Sentinels 182 5.6 Input Validation Loops 185 5.7 Nested Loops 190 Chapter 6 Value-Returning Functions and Modules 203 6.1 Introduction to Value-Returning Functions: Generating Random Numbers 203 6.2 Writing Your Own Value-Returning Functions 214 6.3 The math Module 225 6.4 Storing Functions in Modules 228 Chapter 7 Files and Exceptions 239 7.1 Introduction to File Input and Output 239 7.2 Using Loops to Process Files 256 7.3 Processing Records 263 7.4 Exceptions 276 Chapter 8 Lists and Tuples 295 8.1 Sequences 295 8.2 Introduction to Lists 295 8.3 List Slicing 303 8.4 Finding Items in Lists with the in Operator 306 8.5 List Methods and Useful Built-in Functions 307 8.6 Copying Lists 314 8.7 Processing Lists 316 8.8 Two-Dimensional Lists 328 8.9 Tuples 332 Chapter 9 More About Strings 341 9.1 Basic String Operations 341 9.2 String Slicing 349 9.3 Testing, Searching, and Manipulating Strings 353 Chapter 10 Dictionaries and Sets 371 10.1 Dictionaries 371 10.2 Sets 394 10.3 Serializing Objects 406 Chapter 11 Classes and Object-Oriented Programming 421 11.1 Procedural and Object-Oriented Programming 421 11.2 Classes 425 11.3 Working with Instances 442 11.4 Techniques for Designing Classes 464 Chapter 12 Inheritance 483 12.1 Introduction to Inheritance 483 12.2 Polymorphism 498 Chapter 13 Recursion 509 13.1 Introduction to Recursion 509 13.2 Problem Solving with Recursion 512 13.3 Examples of Recursive Algorithms 516 Chapter 14 GUI Programming 529 14.1 Graphical User Interfaces 529 14.2 Using the tkinter Module 531 14.3 Display Text with Label Widgets 534 14.4 Organizing Widgets with Frames 537 14.5 Button Widgets and Info Dialog Boxes 540 14.6 Getting Input with the Entry Widget 543 14.7 Using Labels as Output Fields 546 14.8 Radio Buttons and Check Buttons 554 Appendix C The ASCII Character Set 577 Appendix D Answers to Checkpoints 579 Index 595  

The Python® programming language is popular for beginners because it uses basic programming concepts without focusing on complicated syntax. Coupled with Tony Gaddis’ writing style, students learn the basics of programming with Python to prepare them for an easy transition into more complicated languages.Control structures, functions, arrays, and pointers are covered before objects and classes.A clear and student-friendly writing style simplifies programming processes for beginning programmers with two to three stepped-out explanations following each major concept.Concise real-world examples that students understand and relate to foster motivation and retention.A variety of exercises in each chapter encourage students to put concepts to work as they are learned. Source code is provided so students can run the programs themselves.In the Spotlight case studies walk students through the design of a problem by showing all steps.Concept boxes throughout the chapter focus students’ attention on key topics.Notes explain interesting or often misunderstood points relevant to the topic at hand.Tips advise students on the best techniques for particular actions.Warnings alert students to common missteps or problems they may encounter.Checkpoints at key locations in each chapter check students’ understanding of important lessons.Tony Gaddis’s best-selling Starting Out with series of textbooks provides accessible, detailed presentations of programming concepts using an approach that will increase confidence and competence in novice programmers. The Starting Out with series includes books on Alice, Python®, Visual Basic®, C++, and JavaTM. View other titles in the series at the Gaddis Books website.VideoNotes are step-by-step video tutorials specifically designed to enhance the programming concepts presented in Gaddis, Starting Out with Python, 2e. Students can view the entire problem-solving process outside of the classroom—when they need help the most. VideoNotes are available with the purchase of a new copy of select titles. Go to www.pearsonhighered.com/videonotes for a brief VideoNotes demo.

This edition is based on Python 3.The coverage of strings has been expanded. String handling now has its own chapter.The coverage of lists and tuples has been expanded. Lists and tuples now have their own chapter.New chapter on dictionaries and sets.The coverage of exception handling has been expanded.A set of VideoNotes have been developed for this edition.