Hello World!: Computer Programming for Kids and Other Beginners

by Warren Sande, Carter Sande

Overview

SUMMARY

A gentle but thorough introduction to the world of computer programming, it is written in language a 12-year-old can follow, but anyone who wants to learn how to program a computer can use it. Even adults. Written by Warren Sande and his son, Carter, and reviewed by professional educators, this book is kid-tested and parent-approved.

ABOUT THIS BOOK

Learn to talk to your computer in its own language! Whether you want to create a game, start a business, or solve an important problem, the first step is learning to write your own programs. Programming is a fun challenge, and it's easy to get started!

This updated and revised edition of Hello World! introduces the world of computer programming in a clear and engaging style. Written by Warren Sande and his son, Carter, it is full of examples that will get you thinking and learning. Reviewed by professional educators, this book is kid-tested and parent-approved. You don't need to know anything about programming to use the book, just the basics of using a computer. If you can start a program and save a file, you'll be off and running!

Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications.

WHAT'S INSIDE

• Explains concepts in clear language
• Lots of pictures, cartoons, and fun examples
• Complete set of practice questions and exercises
• Illustrated in full color

Hello World! uses Python, a programming language designed to be easy to learn. Using fun examples, it brings to life concepts of computing— looping, decisions, input and output, data structures, graphics—and many more.

ABOUT THE AUTHORS

Warren Sande is an electronic systems engineer who uses Python both as a "do anything" scripting language and as a way to teach computers and programming. Carter Sande is a high school student who is passionate about technology. When he's not fixing his school's network and helping his classmates recover lost homework, he likes to ride his bike and write retro video games.

TABLE OF CONTENTS

1. Getting Started
2. Remember This: Memory and Variables
3. Basic Math
4. Types of Data
5. Input
6. GUIs—Graphical User Interfaces
7. Decisions, Decisions
8. Loop the Loop
9. Just for You—Comments
10. Game Time
11. Nested and Variable Loops
12. Collecting Things Together—Lists and Dictionaries
13. Functions
14. Objects
15. Modules
16. Graphics
17. Sprites and Collision Detection
18. A New Kind of Input—Events
19. Sound
20. More GUIs
21. Print Formatting and Strings
22. File Input and Output
23. Take a Chance—Randomness
24. Computer Simulations
25. Skier Explained
26. Python Battle
27. What's Next?

Product Details

ISBN-13:	9781617290923
Publisher:	Manning
Publication date:	12/21/2013
Edition description:	2nd Edition
Pages:	435
Product dimensions:	7.30(w) x 9.20(h) x 1.30(d)
Age Range:	10 - 16 Years

About the Author

Warren Sande is an Electronic Systems Engineer who uses Python (and other languages) in his work, and also uses it to help teach his son about computers and programming. He holds a degree in Electronic Systems Engineering from the University of Regina, Saskatchewan as well as a Diploma in Communication Arts, specializing in Broadcasting, from the Southern Alberta Institute of Technology. He has taught introductory software courses to computer novices.

Carter Sande is a bright, curious, energetic, and thoughtful boy who loves computers, playing the piano, bouncing on the trampoline, and Mario. He has been playing and experimenting with computers from a young age.

Table of Contents

Preface xiii

Acknowledgments xix

About this book xxii

1 Getting Started 1

Installing Python 1

Starting Python with IDLE 2

Instructions, please 3

Interacting with Python 6

Time to program 8

Running your first program 10

If something goes wrong 11

Our second program 13

2 Remember This: Memory and Variables 16

Input, processing, output 16

Names 18

What's in a name? 23

Numbers and strings 24

How "variable" are they? 25

The new me 26

3 Basic Math 30

The four basic operations 31

Operators 31

Order of operations 32

Integer division: Quotient and remainder 34

Exponentiation: Raising to a power 35

Increment and decrement 37

Really big and really small 37

4 Types of Data 42

Changing types 42

Getting more information: type() 46

Type-conversion errors 46

5 Input 48

Input() 49

Putting the input on the same line 49

Inputting numbers 51

Input from the web 52

6 GUIs: Graphical User Interfaces 55

What's a GUI? 55

Our first GUI 56

GUI input 57

Pick your flavor 57

The number guessing game … again 61

Other GUI pieces 62

7 Decisions, Decisions 64

Testing, testing 64

Indenting 66

Am I seeing double? 67

Other kinds of tests 68

What happens if the test is false? 69

Testing for more than one condition 71

Using and 71

Using or 72

Using not 73

8 Loop the Loop 77

Counting loops 78

Using a counting loop 80

A shortcut: range() 81

A matter of style: Loop variable names 82

Counting by steps 85

Counting without numbers 86

While we're on the subject 87

Bailing out of a loop: break and continue 88

9 Just for You: Comments 92

Adding comments 92

Single-line comments 93

End-of-line comments 93

Multiline comments 94

Triple-quoted strings 94

Commenting style 95

Comments in this book 95

Commenting out 96

10 Game Time 97

Skier 97

11 Nested and Variable Loops 102

Nested loops 102

Variable loops 104

Variable nested loops 105

Even more variable nested loops 106

Using nested loops 108

Counting calories 111

12 Collecting Things Together: Lists and Dictionaries 115

What's a list? 115

Creating a list 116

Adding things to a list 116

Getting items from a list 118

"Slicing" a list 119

Modifying items 121

Other ways of adding to a list 122

Deleting from a list 123

Searching a list 125

Looping through a list 126

Sorting lists 127

Mutable and immutable 130

Lists of lists: Tables of data 131

Dictionaries 134

13 Functions 141

Functions: The building blocks 141

Passing arguments to a function 145

Functions that return a value 149

Variable scope 151

A bit of advice on naming variables 155

14 Objects 157

Objects in the real world 158

Objects in Python 158

Object = attributes + methods 160

Creating objects 160

An example class: HotDog 166

Hiding the data 170

Polymorphism and inheritance 171

Thinking ahead 173

15 Modules 176

What's a module? 176

Why use modules? 176

How do we create modules? 177

How do we use modules? 178

Namespaces 179

Standard modules 183

16 Graphics 187

Getting some help: Pygame 187

A Pygame window 188

Drawing in the window 189

Individual pixels 198

Images 203

Let's get moving! 205

Animation 206

Smoother animation 208

Bouncing the ball 209

Wrapping the ball 211

17 Sprites and Collision Detection 215

Sprites 215

Bump! Collision detection 221

Counting time 225

18 A New Kind of Input: Events 230

Events 230

Keyboard events 232

Mouse events 237

Timer events 238

Time for another game-PyPong 241

19 Sound 253

More help from Pygame: mixer 253

Making sounds vs. playing sounds 254

Playing sounds 254

Controlling volume 257

Playing background music 258

Repeating music 259

Adding sounds to PyPong 260

Adding music to PyPong 264

20 More GUIs 269

Working with PyQt 269

Qt Designer 270

Saving the GUI 272

Making our GUI do something 274

The return of event handlers 276

More useful GUIs 277

TempGUI 278

Creating the new GUI 279

Squashing a bug 283

What's on the menu? 284

21 Print Formatting and Strings 290

New lines 291

Horizontal spacing: Tabs 293

Inserting variables in strings 295

Number formatting 296

Formatting, the new way 301

Strings 'n' things 303

22 File Input and Output 311

What's a file? 312

Filenames 312

File locations 313

Opening a file 317

Reading a file 318

Text files and binary files 320

Writing to a file 321

Saving your stuff in files: pickle 325

Game time again-Hangman 327

23 Take a Chance: Randomness 334

What's randomness? 335

Rolling the dice 335

Creating a deck of cards 340

Crazy Eights 345

24 Computer Simulations 358

Modeling the real world 358

Lunar Lander 359

Keeping time 364

Time objects 365

Virtual Pet 371

25 Skier Explained 382

The skier 382

The obstacles 386

26 Making Network Connections with Sockets 395

What's the difference between text and bytes? 396

Servers 398

Getting data from the client 402

Making a chat server 402

27 What's Next? 415

For younger programmers 415

Python 416

Game programming and Pygame 416

Other game programming (non-Python) 416

Keep it BASIC 417

Websites 417

Mobile apps 417

Look around 417

Appendix A Variable Naming Rules 419

Appendix B Differences Between Python 3 and 2 421

Appendix C Answers to Self-Test Questions 424

List of Code Listings 455

Index 459