Starting Out with Python

In Starting Out with Python#xAE;, Second EditionTony Gaddis#x19; evenly-paced, accessible coverage introduces students to the basics of programming and prepares them to transition into more complicated languages. Python, an easy-to-learn and increasingly popular object-oriented language, allows readers to become comfortable with the fundamentals of programming without the troublesome syntax that can be challenging for novices. With the knowledge acquired using Python, students gain confidence in their skills and learn to recognize the logic behind developing high-quality programs. Starting Out with Pythondiscusses control structures, functions, arrays, and pointers before objects and classes. As with all Gaddis texts, clear and easy-to-read code listings, concise and practical real-world examples, detail-oriented explanations, and an abundance of exercises appear in every chapter. This text is intended for a one-semester introductory programming course for students with limited programming experience.

Tony Gaddis is the author of the Starting Out with series including Starting Out with Alice, C++, Java™, Visual Basic^® 2008, Programming Logic & Design, and Python^®. Visit the Gaddis Books website for more information on Gaddis’ titles. Gaddis teaches computer science courses at Haywood Community College in North Carolina. He previously taught programming for several corporations and government agencies, including NASA's Kennedy Space Center. Gaddis is a highly acclaimed instructor who was selected as the North Carolina Community College "Teacher of the Year" in 1994, and who received the Teaching Excellence award from the National Institute for Staff and Organizational Development in 1997.

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 A Installing Python 567

Appendix B Introduction to IDLE 569

Appendix C The ASCII Character Set 577

Appendix D Answers to Checkpoints 579

Index 595