[CHAPTER] 1 INTRODUCTION 1

Transcription

1 FM_TOC C /28/11 9:29 AM Page iii Table of Contents [CHAPTER] 1 INTRODUCTION Two Fundamental Ideas of Computer Science: Algorithms and Information Processing Algorithms Information Processing Exercises The Structure of a Modern Computer System Computer Hardware Computer Software Exercises A Not-So-Brief History of Computing Systems Before Electronic Digital Computers The First Electronic Digital Computers ( ) The First Programming Languages ( ) Integrated Circuits, Interaction, and Timesharing ( ) Personal Computing and Networks ( ) Consultation, Communication, and Ubiquitous Computing (1990 Present) Getting Started with Python Programming Running Code in the Interactive Shell Input, Processing, and Output Editing, Saving, and Running a Script Behind the Scenes: How Python Works Exercises Detecting and Correcting Syntax Errors Exercises...32 Suggestions for Further Reading...32 Summary...33 Review Questions...35 Projects...37 [CHAPTER] 2 SOFTWARE DEVELOPMENT, DATA TYPES, AND EXPRESSIONS The Software Development Process Exercises Case Study: Income Tax Calculator Request Analysis...44 Not For Design...44 Sale Implementation (Coding) Testing...46

2 FM_TOC C /28/11 9:29 AM Page iv 2.3 Strings, Assignment, and Comments Data Types String Literals Escape Sequences String Concatenation Variables and the Assignment Statement Program Comments and Docstrings Exercises Numeric Data Types and Character Sets Integers Floating-Point Numbers Character Sets Exercises Expressions Arithmetic Expressions Mixed-Mode Arithmetic and Type Conversions Exercises Using Functions and Modules Calling Functions: Arguments and Return Values The math Module The Main Module Program Format and Structure Running a Script from a Terminal Command Prompt Exercises...70 Summary...70 Review Questions...72 Projects...73 [CHAPTER] 3 CONTROL STATEMENTS Definite Iteration: The for Loop Executing a Statement a Given Number of Times Count-Controlled Loops Augmented Assignment Loop Errors: Off-by-One Error Traversing the Contents of a Data Sequence Specifying the Steps in the Range Loops That Count Down Exercises Formatting Text for Output Exercises Case Study: An Investment Report Request Analysis Design Implementation (Coding) Testing Selection: if and if-else Statements The Boolean Type, Comparisons, and Boolean Expressions if-else Statements...92

3 FM_TOC C /28/11 9:29 AM Page v One-Way Selection Statements Multi-way if Statements Logical Operators and Compound Boolean Expressions Short-Circuit Evaluation Testing Selection Statements Exercises Conditional Iteration: The while Loop The Structure and Behavior of a while Loop Count Control with a while Loop The while True Loop and the break Statement Random Numbers Loop Logic, Errors, and Testing Exercises Case Study: Approximating Square Roots Request Analysis Design Implementation (Coding) Testing Summary Review Questions Projects [CHAPTER] 4 STRINGS AND TEXT FILES Accessing Characters and Substrings in Strings The Structure of Strings The Subscript Operator Slicing for Substrings Testing for a Substring with the in Operator Exercises Data Encryption Exercises Strings and Number Systems The Positional System for Representing Numbers Converting Binary to Decimal Converting Decimal to Binary Conversion Shortcuts Octal and Hexadecimal Numbers Exercises String Methods Exercises Text Files Text Files and Their Format Writing Text to a File Writing Numbers to a File Reading Text from a File Reading Numbers from a File Not For Accessing and Manipulating Sale Files and Directories on Disk...146

4 FM_TOC C /28/11 9:29 AM Page vi 4.5 Exercises Case Study: Text Analysis Request Analysis Design Implementation (Coding) Testing Summary Review Questions Projects [CHAPTER] 5 LISTS AND DICTIONARIES Lists List Literals and Basic Operators Replacing an Element in a List List Methods for Inserting and Removing Elements Searching a List Sorting a List Mutator Methods and the Value None Aliasing and Side Effects Equality: Object Identity and Structural Equivalence Example: Using a List to Find the Median of a Set of Numbers Tuples Exercises Defining Simple Functions The Syntax of Simple Function Definitions Parameters and Arguments The return Statement Boolean Functions Defining a main Function Exercises Case Study: Generating Sentences Request Analysis Design Implementation (Coding) Testing Dictionaries Dictionary Literals Adding Keys and Replacing Values Accessing Values Removing Keys Traversing a Dictionary Example: The Hexadecimal System Revisited Example: Finding the Mode of a List of Values Exercises...190

5 FM_TOC C /28/11 9:29 AM Page vii 5.5 Case Study: Nondirective Psychotherapy Request Analysis Design Implementation (Coding) Testing Summary Review Questions Projects [CHAPTER] 6 DESIGN WITH FUNCTIONS Functions as Abstraction Mechanisms Functions Eliminate Redundancy Functions Hide Complexity Functions Support General Methods with Systematic Variations Functions Support the Division of Labor Exercises Problem Solving with Top-Down Design The Design of the Text-Analysis Program The Design of the Sentence-Generator Program The Design of the Doctor Program Exercises Design with Recursive Functions Defining a Recursive Function Tracing a Recursive Function Using Recursive Definitions to Construct Recursive Functions Recursion in Sentence Structure Infinite Recursion The Costs and Benefits of Recursion Exercises Case Study: Gathering Information from a File System Request Analysis Design Implementation (Coding) Managing a Program s Namespace Module Variables, Parameters, and Temporary Variables Scope Lifetime Default (Keyword) Arguments Exercises Higher-Order Functions (Advanced Topic) Functions as First-Class Data Objects Mapping Filtering Reducing Using lambda to Create Anonymous Functions Not For Creating Jump Tables Sale

6 FM_TOC C /28/11 9:29 AM Page viii 6.6 Exercises Summary Review Questions Projects [CHAPTER] 7 SIMPLE GRAPHICS AND IMAGE PROCESSING Simple Graphics Overview of Turtle Graphics Turtle Operations Object Instantiation and the turtle Module Drawing Two-Dimensional Shapes Taking a Random Walk Colors and the RGB System Example: Drawing with Random Colors Examining an Object s Attributes Manipulating a Turtle s Screen Setting up a cfg File and Running IDLE Exercises Case Study: Recursive Patterns in Fractals Request Analysis Design Implementation (Coding) Image Processing Analog and Digital Information Sampling and Digitizing Images Image File Formats Image-Manipulation Operations The Properties of Images The images Module A Loop Pattern for Traversing a Grid A Word on Tuples Converting an Image to Black and White Converting an Image to Grayscale Copying an Image Blurring an Image Edge Detection Reducing the Image Size Exercises Summary Review Questions Projects [CHAPTER] 8 DESIGN WITH CLASSES Getting Inside Objects and Classes A First Example: The Student Class Docstrings Method Definitions...298

7 FM_TOC C /28/11 9:29 AM Page ix The init Method and Instance Variables The str Method Accessors and Mutators The Lifetime of Objects Rules of Thumb for Defining a Simple Class Exercises Case Study: Playing the Game of Craps Request Analysis Design Implementation (Coding) Data-Modeling Examples Rational Numbers Rational Number Arithmetic and Operator Overloading Comparison Methods Equality and the eq Method Savings Accounts and Class Variables Putting the Accounts into a Bank Using pickle for Permanent Storage of Objects Input of Objects and the try-except Statement Playing Cards Exercises Case Study: An ATM Request Analysis Design Implementation (Coding) Structuring Classes with Inheritance and Polymorphism Inheritance Hierarchies and Modeling Example: A Restricted Savings Account Example: The Dealer and a Player in the Game of Blackjack Polymorphic Methods Abstract Classes The Costs and Benefits of Object-Oriented Programming Exercises Summary Review Questions Projects [CHAPTER] 9 GRAPHICAL USER INTERFACES The Behavior of Terminal-Based Programs and GUI-Based Programs The Terminal-Based Version The GUI-Based Version Event-Driven Programming Exercises Coding Simple GUI-Based Programs Windows and Labels Not For Displaying Images Sale Command Buttons and Responding to Events Viewing the Images of Playing Cards...360

8 FM_TOC C /28/11 9:29 AM Page x Entry Fields for the Input and Output of Text Using Pop-up Dialog Boxes Exercises Case Study: A GUI-Based ATM Request Analysis Design Implementation (Coding) Other Useful GUI Resources Colors Text Attributes Sizing and Justifying an Entry Sizing the Main Window Grid Attributes Using Nested Frames to Organize Components Multi-Line Text Widgets Scrolling List Boxes Mouse Events Keyboard Events Exercises Summary Review Questions Projects [CHAPTER] 10 MULTITHREADING, NETWORKS, AND CLIENT/SERVER PROGRAMMING Threads and Processes Threads Sleeping Threads Producer, Consumer, and Synchronization Exercises Networks, Clients, and Servers IP Addresses Ports, Servers, and Clients Sockets and a Day/Time Client Script A Day/Time Server Script A Two-Way Chat Script Handling Multiple Clients Concurrently Setting Up Conversations for Others Exercises Case Study: A Multi-Client Chat Room Request Analysis Design Implementation (Coding) Summary Review Questions Projects...430

9 FM_TOC C /28/11 9:29 AM Page xi [ONLINE CHAPTER] 11 SEARCHING, SORTING, AND COMPLEXITY ANALYSIS (Available on the publisher s Web site at Measuring the Efficiency of Algorithms Measuring the Run Time of an Algorithm Counting Instructions Measuring the Memory Used by an Algorithm 11.1 Exercises 11.2 Complexity Analysis Orders of Complexity Big-O Notation The Role of the Constant of Proportionality 11.2 Exercises 11.3 Search Algorithms Search for a Minimum Linear Search of a List Best-Case, Worst-Case, and Average-Case Performance Binary Search of a List Comparing Data Items 11.3 Exercises 11.4 Sort Algorithms Selection Sort Bubble Sort Insertion Sort Best-Case, Worst-Case, and Average-Case Performance Revisited 11.4 Exercises 11.5 An Exponential Algorithm: Recursive Fibonacci 11.6 Converting Fibonacci to a Linear Algorithm 11.7 Case Study: An Algorithm Profiler Request Analysis Design Implementation (Coding) Summary Review Questions Projects [APPENDIX] A PYTHON RESOURCES 433 A.1 Installing Python on Your Computer A.2 Using the Terminal Command Prompt, IDLE, and Other IDEs [APPENDIX] B INSTALLING THE images LIBRARY 437 [APPENDIX] C API FOR IMAGE PROCESSING 439 [APPENDIX] D TRANSITION FROM PYTHON TO JAVA AND C GLOSSARY 443 INDEX 455