Python Programming for Raspberry Pi, Sams Teach Yourself in 24 Hours

Richard Blum has worked in the IT industry for over 25 years as a network and systems administrator, managing Microsoft, Unix, Linux, and Novell servers for a network with more than 3,500 users. He has developed and teaches programming and Linux courses via the Internet to colleges and universities worldwide. Rich has a master’s degree in management information systems from Purdue University and is the author of several Linux books, including Linux Command Line and Shell Scripting Bible (coauthored with Christine Bresnahan, 2011, Wiley), Linux for Dummies , 9th edition (2009, Wiley), and Professional Linux Programming (coauthored with Jon Masters, 2007, Wiley). When he’s not busy being a computer nerd, Rich enjoys spending time with his wife, Barbara, and two daughters, Katie Jane and Jessica.   Christine Bresnahan started working in the IT industry more than 25 years ago as a system administrator. Christine is currently an adjunct professor at Ivy Tech Community College in Indianapolis, Indiana, teaching Python programming, Linux system administration, and Linux security classes. Christine produces Unix/Linux educational material and is the author of Linux Bible , 8th edition (coauthored with Christopher Negus, 2012, Wiley) and Linux Command Line and Shell Scripting Bible (coauthored with Richard Blum, 2011, Wiley).She has been an enthusiastic owner of a Raspberry Pi since 2012.

Introduction 1

Programming with Python 1

Who Should Read This Book? 2

Conventions Used in This Book 3

Part I: The Raspberry Pi Programming Environment

HOUR 1: Setting Up the Raspberry Pi 7

What Is a Raspberry Pi? 7

Acquiring a Raspberry Pi 9

What Raspberry Pi Peripherals Are Necessary? 11

Nice Additional Peripherals 17

Deciding How to Purchase Peripherals 19

Getting Your Raspberry Pi Working 19

Troubleshooting Your Raspberry Pi 24

Summary 25

Q&A 25

Workshop 26

HOUR 2: Understanding the Raspbian Linux Distribution 27

Learning About Linux 27

Interacting with the Raspbian Command Line 28

Interacting with the Raspbian GUI 33

Summary 43

Q&A 43

Workshop 44

HOUR 3: Setting Up a Programming Environment 45

Exploring Python 45

Checking Your Python Environment 46

Installing Python and Tools 48

Learning About the Python Interpreter 50

Learning About the Python Interactive Shell 51

Learning About the Python Development Environment Shell 54

Creating Python Scripts 59

Knowing Which Tool to Use and When 65

Summary 66

Q&A 66

Workshop 67

Part II: Python Fundamentals

HOUR 4: Understanding Python Basics 71

Producing Python Script Output 71

Formatting Scripts for Readability 78

Understanding Python Variables 81

Assigning Value to Python Variables 82

Learning About Python Data Types 86

Allowing Python Script Input 88

Summary 94

Q&A 95

Workshop 95

HOUR 5: Using Arithmetic in Your Programs 97

Working with Math Operators 97

Calculating with Fractions 103

Using Complex Number Math 105

Getting Fancy with the math Module 106

Using the NumPy Math Libraries 110

Summary 112

Q&A 113

Workshop 113

HOUR 6: Controlling Your Program 115

Working with the if Statement 115

Grouping Multiple Statements 117

Adding Other Options with the else Statement 118

Adding More Options Using the elif Statement 120

Comparing Values in Python 121

Checking Complex Conditions 126

Negating a Condition Check 127

Summary 128

Q&A 129

Workshop 129

HOUR 7: Learning About Loops 131

Performing Repetitive Tasks 131

Using the for Loop for Iteration 132

Using the while Loop for Iteration 143

Creating Nested Loops 149

Summary 150

Q&A 150

Workshop 151

Part III: Advanced Python

HOUR 8: Using Lists and Tuples 155

Introducing Tuples 155

Introducing Lists 160

Using Multidimensional Lists to Store Data 167

Working with Lists and Tuples in Your Scripts 168

Creating Lists by Using List Comprehensions 170

Working with Ranges 170

Summary 172

Q&A 172

Workshop 172

HOUR 9: Dictionaries and Sets 175

Understanding Python Dictionary Terms 175

Exploring Dictionary Basics 176

Programming with Dictionaries 182

Understanding Python Sets 187

Exploring Set Basics 187

Obtaining Information from a Set 189

Modifying a Set 192

Programming with Sets 193

Summary 197

Q&A 197

Workshop 197

HOUR 10: Working with Strings 199

The Basics of Using Strings 199

Using Functions to Manipulate Strings 202

Formatting Strings for Output 209

Summary 215

Q&A 215

Workshop 215

HOUR 11: Using Files 217

Understanding Linux File Structures 217

Opening a File 221

Reading a File 224

Closing a File 230

Writing to a File 231

Summary 237

Q&A 237

Workshop 238

HOUR 12: Creating Functions 239

Utilizing Python Functions in Your Programs 239

Returning a Value 243

Passing Values to Functions 244

Handling Variables in a Function 250

Using Lists with Functions 253

Using Recursion with Functions 254

Summary 255

Q&A 256

Workshop 256

HOUR 13: Working with Modules 257

Introducing Module Concepts 257

Exploring Standard Modules 259

Learning About Python Modules 261

Creating Custom Modules 265

Summary 275

Q&A 275

Workshop 276

HOUR 14: Exploring the World of Object-Oriented Programming 277

Understanding the Basics of Object-Oriented Programming 277

Defining Class Methods 280

Sharing Your Code with Class Modules 287

Summary 290

Q&A 290

Workshop 290

HOUR 15: Employing Inheritance 293

Learning About the Class Problem 293

Understanding Subclasses and Inheritance 294

Using Inheritance in Python 296

Using Inheritance in Python Scripts 302

Summary 314

Q&A 314

Workshop 315

HOUR 16: Regular Expressions 317

What Are Regular Expressions? 317

Working with Regular Expressions in Python 319

Defining Basic Patterns 321

Using Advanced Regular Expressions Features 330

Working with Regular Expressions in Your Python Scripts 332

Summary 334

Q&A 335

Workshop 335

HOUR 17: Exception Handling 337

Understanding Exceptions 337

Handling Exceptions 342

Handling Multiple Exceptions 344

Summary 357

Q&A 357

Workshop 357

Part IV: Graphical Programming

HOUR 18: GUI Programming 361

Programming for a GUI Environment 361

Examining Python GUI Packages 363

Using the tkinter Package 364

Exploring the tkinter Widgets 372

Summary 384

Q&A 384

Workshop 384

HOUR 19: Game Programming 387

Understanding Game Programming 387

Learning About Game Frameworks and Libraries 388

Setting Up the PyGame Library 389

Using PyGame 394

Learning More About PyGame 403

Dealing with PyGame Action 408

Summary 418

Q&A 418

Workshop 418

Part V: Business Programming

HOUR 20: Using the Network 423

Finding the Python Network Modules 423

Working with Email Servers 424

Working with Web Servers 432

Linking Programs Using Socket Programming 438

Summary 445

Q&A 445

Workshop 446

HOUR 21: Using Databases in Your Programming 447

Working with the MySQL Database 447

Using the PostgreSQL Database 458

Summary 466

Q&A 466

Workshop 467

HOUR 22: Web Programming 469

Running a Web Server on the Pi 469

Programming with the Common

Gateway Interface 473

Expanding Your Python Webpages 475

Processing Forms 482

Summary 488

Q&A 488

Workshop 488

Part VI: Raspberry Pi Python Projects1

HOUR 23: Creating Basic Pi/Python Projects 493

Thinking About Basic Pi/Python Projects 493

Displaying HD Images via Python 493

Playing Music 514

Creating a Special Presentation 521

Summary 526

Q&A 526

Workshop 526

HOUR 24: Working with Advanced Pi/Python Projects 529

Exploring the GPIO Interface 529

Using the RPi.GPIO Module 535

Controlling GPIO Output 536

Detecting GPIO Input 542

Summary 548

Q&A 549

Workshop 549

Part VII: Appendix

APPENDIX A: Loading the Raspbian Operating System onto an SD Card 553

Windows: Loading Raspbian onto an SD Card 553

Linux: Loading Raspbian onto an SD Card 556

Mac: Loading Raspbian onto an SD Card 558

Index 561