Hello World!: Computer Programming for Kids

Hello World!
Contents
Preface
	What is programming?
	Python—a language for us and the computer
	Why learn programming?
	Why Python?
Acknowledgments
	Acknowledgments for the First Edition
	Acknowledgments for the Second Edition
	Acknowledgments for the Third Edition
About this book
	What you need
	What you don’t need
		Using this book
		Follow along with the examples
		Installing Python
		Type in the programs
		Do the quiz questions
	Carter says
	What’s new in the Third Edition
	Note to parents and teachers
Chapter 1 Getting Started
	Installing Python
	Starting Python with IDLE
	Instructions, please
		If it doesn’t work
	Interacting with Python
	Time to program
	Running your first program
	If something goes wrong
		Syntax errors
		Runtime errors
	Our second program
		What did you learn?
		Test your knowledge
		Try it out
Chapter 2 Remember This: Memory and Variables
	Input, processing, output
	Names
	What’s in a name?
	Numbers and strings
		Long strings
	How “variable” are they?
	The new me
		What did you learn?
		Test your knowledge
		Try it out
Chapter 3 Basic Math
	The four basic operations
	Operators
	Order of operations
	Integer division: Quotient and remainder
	Exponentiation: Raising to a power
	Increment and decrement
	Really big and really small
		E-notation
		Exponents vs. E-notation
		What did you learn?
		Test your knowledge
		Try it out
Chapter 4 Types of Data
	Changing types
		Changing an int to a float
		Changing a float to an int
		Changing a string to a float
	Getting more information: type()
	Type-conversion errors
		What did you learn?
		Test your knowledge
		Try it out
Chapter 5 Input
	input()
	Putting the input on the same line
		A shortcut for input() prompts
	Inputting numbers
		Using int() with input()
	Input from the web
		What did you learn?
		Test your knowledge
		Try it out
Chapter 6 GUIs: Graphical User Interfaces
	What’s a GUI?
	Our first GUI
		Let’s get GUI-ing
	GUI input
	Pick your flavor
		Dialog box with multiple buttons
		Choice box
		Text input
		Default input
		What about numbers?
	The number guessing game … again
	Other GUI pieces
		What did you learn?
		Test your knowledge
		Try it out
Chapter 7 Decisions, Decisions
	Testing, testing
	Indenting
	Am I seeing double?
	Other kinds of tests
	What happens if the test is false?
	Testing for more than one condition
	Using and
	Using or
	Using not
		What did you learn?
		Test your knowledge
		Try it out
Chapter 8 Loop the Loop
	Counting loops
		Runaway loops
		What are the square brackets for?
	Using a counting loop
	A shortcut: range()
	A matter of style: Loop variable names
		A range() shortcut
	Counting by steps
	Counting without numbers
	While we’re on the subject …
	Bailing out of a loop: break and continue
		Jumping ahead: continue
		Bailing out: break
		What did you learn?
		Test your knowledge
		Try it out
Chapter 9 Just for You: Comments
	Adding comments
	Single-line comments
	End-of-line comments
	Multiline comments
	Triple-quoted strings
	Commenting style
	Comments in this book
	Commenting out
		What did you learn?
		Test your knowledge
		Try it out
Chapter 10 Game Time
	Skier
		Try it out
Chapter 11 Nested and Variable Loops
	Nested loops
	Variable loops
	Variable nested loops
	Even more variable nested loops
	Using nested loops
	Counting calories
		What did you learn?
		Test your knowledge
		Try it out
Chapter 12 Collecting Things Together: Lists and Dictionaries
	What’s a list?
	Creating a list
	Adding things to a list
		What’s the dot?
		Lists can hold anything
	Getting items from a list
		Why does the index start at 0, not 1?
	“Slicing” a list
		Slice shorthand
	Modifying items
	Other ways of adding to a list
		Adding to the end: append()
		Extending the list: extend()
		Inserting an item: insert()
		The difference between append() and extend()
	Deleting from a list
		Deleting with remove()
		Deleting with del
		Deleting with pop()
	Searching a list
		The in keyword
		Finding the index
	Looping through a list
	Sorting lists
		Sorting in reverse order
		Another way to sort: sorted()
	Mutable and immutable
		Tuple: An immutable list
	Lists of lists: Tables of data
		Getting a single value from the table
	Dictionaries
		A bit more about dictionaries
		What did you learn?
		Test your knowledge
		Try it out
Chapter 13 Functions
	Functions: The building blocks
		Creating a function
		Calling a function
	Passing arguments to a function
		Functions with more than one argument
		How many is too many?
	Functions that return a value
		Returning a value
	Variable scope
		Local variables
		Global variables
		Forcing a global
	A bit of advice on naming variables
		What did you learn?
		Test your knowledge
		Try it out
Chapter 14 Objects
	Objects in the real world
	Objects in Python
		What are attributes?
		What are methods?
	Object = attributes + methods
	Creating objects
		Creating an instance of an object
		Initializing an object
		A “magic” method: __str__()
		What’s self?
	An example class: HotDog
	Hiding the data
	Polymorphism and inheritance
		Polymorphism: Same method, different behavior
		Inheritance: Learning from your parents
	Thinking ahead
		What did you learn?
		Test your knowledge
		Try it out
Chapter 15 Modules
	What’s a module?
	Why use modules?
		Buckets of blocks
	How do we create modules?
	How do we use modules?
	Namespaces
		What’s a namespace?
		Importing namespaces
		Importing using from
		Whew!
	Standard modules
		Time
		Random numbers
		What did you learn?
		Test your knowledge
		Try it out
Chapter 16 Graphics
	Getting some help: Pygame
	A Pygame window
	Drawing in the window
		What’s the “flip”?
		How to make a circle
		Pygame surfaces
		Colors in Pygame
		Locations: Screen coordinates
		Size of shapes
		Line width
		Modern art?
	Individual pixels
		Connect the dots
		Connect the dots, again
		Drawing point-by-point
	Images
	Let’s get moving!
	Animation
		Erasing images
		What’s under there?
	Smoother animation
		Keeping the ball moving
	Bouncing the ball
		Bouncing in 2-D
	Wrapping the ball
		What did you learn?
		Test your knowledge
		Try it out
Chapter 17 Sprites and Collision Detection
	Sprites
		A sprite class
		A move() method
	Bump! Collision detection
		Rect collision vs. pixel-perfect collision
	Counting time
		Controlling the frame rate with pygame.time.Clock()
		Checking the frame rate
		Scaling the frame rate
		What did you learn?
		Test your knowledge
		Try it out
Chapter 18 A New Kind of Input: Events
	Events
		The event loop
		The event queue
		Event handlers
	Keyboard events
		Key events
		Repeating keys
		Event names and key names
	Mouse events
	Timer events
	Time for another game—PyPong
		The ball
		The paddle
		Controlling the paddle
		Keeping score and displaying it with pygame.font
		Keeping track of lives
		Adding a life counter
		Game over
		What did you learn?
		Test your knowledge
		Try it out
Chapter 19 Sound
	More help from Pygame: mixer
	Making sounds vs. playing sounds
	Playing sounds
		Using pygame.mixer
	Controlling volume
	Playing background music
	Repeating music
	Adding sounds to PyPong
		More wacky sounds
	Adding music to PyPong
		What did you learn?
		Test your knowledge
		Try it out
Chapter 20 More GUIs
	Working with PyQt
	Qt Designer
		Adding a button
		Changing the button
	Saving the GUI
	Making our GUI do something
	The return of event handlers
		What is self?
		Moving the button
	More useful GUIs
	TempGUI
		TempGUI components
	Creating the new GUI
		Converting Celsius to Fahrenheit
		Converting Fahrenheit to Celsius
		A small improvement
	Squashing a bug
	What’s on the menu?
		Adding a menu item
		Hotkeys
		What did you learn?
		Test your knowledge
		Try it out
Chapter 21 Print Formatting and Strings
	New lines
		print and end=''
		Adding our own newlines
		Special printing codes
	Horizontal spacing: Tabs
		How do we print a backslash?
	Inserting variables in strings
	Number formatting
		Integers: %d or %i
		Floating point numbers: %f or %F
		E-notation: %e and %E
		Automatic float or E-notation: %g and %G
		How do we print a percent sign?
		More than one format string
		Storing formatted numbers
	Formatting, the new way
		F-strings
	Strings ’n’ things
		Splitting strings
		Joining strings
		Searching for strings
		Searching anywhere in a string: in and index()
		Removing part of a string
		Changing case
		What did you learn?
		Test your knowledge
		Try it out
Chapter 22 File Input and Output
	What’s a file?
	Filenames
	File locations
		Finding where you are
		Enough about paths!
	Opening a file
	Reading a file
		Reading one line at a time
		Going back to the start
	Text files and binary files
	Writing to a file
		Appending to a file
		Writing to a file using write mode
		Writing to a file using print()
	Saving your stuff in files: pickle
		Pickling
		Unpickling
	Game time again—Hangman
		The Hangman GUI
		Getting words from the word list
		Revealing the man
		Checking the letter guesses
		What did you learn?
		Test your knowledge
		Try it out
Chapter 23 Take a Chance: Randomness
	What’s randomness?
	Rolling the dice
		More than one die
		Ten in a row
	Creating a deck of cards
		Shuffling the deck
		A card object
	Crazy Eights
		The main loop
		The up card
		The active suit
		The player’s turn
		Displaying the hand
		Getting the player’s choice
		The computer’s turn
		Keeping score
		What did you learn?
		Test your knowledge
		Try it out
Chapter 24 Computer Simulations
	Modeling the real world
	Lunar Lander
		Simulating the landing
		Pygame returns
	Keeping time
	Time objects
		Difference between two times
		Small pieces of time
		Saving time to a file
	Virtual Pet
		The GUI
		The algorithm
		Simple animation
		Try, try again
		What did you learn?
		Test your knowledge
		Try it out
Chapter 25 Skier Explained
	The skier
	The obstacles
		Creating individual obstacles
		Creating a map of obstacles
		What did you learn?
		Try it out
Chapter 26 Making Network Connections with Sockets
	What’s the difference between text and bytes?
	Servers
	Getting data from the client
	Making a chat server
		A little about IP addresses
		Creating a chat client
		What did you learn?
		Test your Knowledge
		Try it out
chapter 27 What’s Next?
	For younger programmers
	Python
	Game programming and Pygame
	Other game programming (non-Python)
	Keep it BASIC
	Websites
	Mobile apps
	Look around
APPENDIX A Variable Naming Rules
APPENDIX B Differences Between Python 3 and 2
	print
	input()
	Integer division
	range()
	Bytes and character encodings
	Python 2 to 3 conversion
APPENDIX C Answers to Self-Test Questions
	Chapter 1: Getting Started
		Test your knowledge
		Try it out
	Chapter 2: Remember This: Memory and Variables
		Test your knowledge
		Try it out
	Chapter 3: Basic Math
		Test your knowledge
		Try it out
	Chapter 4: Types of Data
		Test your knowledge
		Try it out
	Chapter 5: Input
		Test your knowledge
		Try It Out
	Chapter 6: GUIs: Graphical User Interfaces
		Test your knowledge
		Try it out
	Chapter 7: Decisions, Decisions
		Test your knowledge
		Try it out
	Chapter 8: Loop the Loop
		Test your knowledge
		Try it out
	Chapter 9: Just for You—Comments
		Try it out
	Chapter 10: Game Time
		Try it out
	Chapter 11: Nested and Variable Loops
		Test your knowledge
		Try it out
	Chapter 12: Collecting Things Together— Lists and Dictionaries
		Test your knowledge
		Try it out
	Chapter 13: Functions
		Test your knowledge
		Try it out
	Chapter 14: Objects
		Test your knowledge
		Try it out
	Chapter 15: Modules
		Test your knowledge
		Try it out
	Chapter 16: Graphics
		Test your knowledge
		Try it out
	Chapter 17: Sprites and Collision Detection
		Test your knowledge
	Chapter 18: A New Kind of Input: Events
		Test your knowledge
		Try it out
	Chapter 19: Sound
		Test your knowledge
		Try it out
	Chapter 20: More GUIs
		Test your knowledge
		Try it out
	Chapter 21: Print Formatting and Strings
		Test your knowledge
		Try it out
	Chapter 22: File Input and Output
		Test your knowledge
		Try it out
	Chapter 23: Take a Chance—Randomness
		Test your knowledge
		Try it out
	Chapter 24: Computer Simulations
		Test your knowledge
		Try it out
	Chapter 26: Making Network Connections with Sockets
		Test your knowledge
		Try it out
List of Code Listings
Index
	Symbols
	Math and comparison operators
	Numerics
	A
	B
	C
	D
	E
	F
	G
	H
	I
	K
	L
	M
	N
	O
	P
	Q
	R
	S
	T
	U
	V
	W
	X
	Y
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