Beginning Programming with Python For Dummies E-Book

John Paul Mueller

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 494

Veröffentlichungsjahr: 2014

Beschreibung

Learn Python--the fun and easy way--and get in theprogramming game today! Python is one of the fastest growing programming languages, andno wonder. It requires three to five times less time thandeveloping in Java, is a great building block for learning bothprocedural and object-oriented programming concepts, and is anideal language for data analysis. Beginning Programming withPython For Dummies is the perfect guide to this dynamic andpowerful programming language--even if you've never codedbefore! Author John Paul Mueller draws on his vast programmingknowledge and experience to guide you step-by-step through thesyntax and logic of programming with Python and provides severalreal-world programming examples to give you hands-on experiencetrying out what you've learned. * Provides a solid understanding of basic computer programmingconcepts and helps familiarize you with syntax and logic * Explains the fundamentals of procedural and object-orientedprogramming * Shows how Python is being used for data analysis and otherapplications * Includes short, practical programming samples to apply yourskills to real-world programming scenarios Whether you've never written a line of code or are just tryingto pick up Python, there's nothing to fear with the fun andfriendly Beginning Programming with Python For Dummiesleading the way.

Leseprobe

Beginning Programming with Python® For Dummies®

Published by: John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030-5774, www.wiley.com

Copyright © 2014 by John Wiley & Sons, Inc., Hoboken, New Jersey

Media and software compilation copyright © 2014 by John Wiley & Sons, Inc. All rights reserved.

Published simultaneously in Canada

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Library of Congress Control Number: 2014935516

ISBN 978-1-118-89145-2 (pbk); ISBN 978-1-118-89147-6 (ebk); ISBN ePDF 978-1-118-89149-0 (ebk)

Manufactured in the United States of America

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Beginning Programming with Python For Dummies

Visit www.dummies.com/cheatsheet/beginningprogrammingwithpython to view this book's cheat sheet.

Table of Contents

Introduction

About This Book

Foolish Assumptions

Icons Used in This Book

Beyond the Book

Where to Go from Here

Part I: Getting Started with Python

Chapter 1: Talking to Your Computer

Understanding Why You Want to Talk to Your Computer

Knowing that an Application is a Form of Communication

Thinking about procedures you use daily

Writing procedures down

Seeing applications as being like any other procedure

Understanding that computers take things literally

Defining What an Application Is

Understanding that computers use a special language

Helping humans speak to the computer

Understanding Why Python is So Cool

Unearthing the reasons for using Python

Deciding how you can personally benefit from Python

Discovering which organizations use Python

Finding useful Python applications

Comparing Python to other languages

Chapter 2: Getting Your Own Copy of Python

Downloading the Version You Need

Installing Python

Working with Windows

Working with the Mac

Working with Linux

Accessing Python on Your Machine

Using Windows

Using the Mac

Using Linux

Testing Your Installation

Chapter 3: Interacting with Python

Opening the Command Line

Starting Python

Using the command line to your advantage

Using Python environment variables to your advantage

Typing a Command

Telling the computer what to do

Telling the computer you’re done

Seeing the result

Using Help

Getting into help mode

Asking for help

Leaving help mode

Obtaining help directly

Closing the Command Line

Chapter 4: Writing Your First Application

Understanding the Integrated DeveLopment Environment (IDLE)

Starting IDLE

Using standard commands

Understanding color coding

Getting GUI help

Configuring IDLE

Creating the Application

Opening a new window

Typing the command

Saving the file

Running the Application

Understanding the Use of Indentation

Adding Comments

Understanding comments

Using comments to leave yourself reminders

Using comments to keep code from executing

Loading and Running Existing Applications

Using the command line or terminal window

Using the Edit window

Using the Python Shell window or Python command line

Closing IDLE

Part II: Talking the Talk

Chapter 5: Storing and Modifying Information

Storing Information

Seeing variables as storage boxes

Using the right box to store the data

Defining the Essential Python Data Types

Putting information into variables

Understanding the numeric types

Understanding Boolean values

Understanding strings

Working with Dates and Times

Chapter 6: Managing Information

Controlling How Python Views Data

Making comparisons

Understanding how computers make comparisons

Working with Operators

Defining the operators

Understanding operator precedence

Creating and Using Functions

Viewing functions as code packages

Understanding code reusability

Defining a function

Accessing functions

Sending information to functions

Returning information from functions

Comparing function output

Getting User Input

Chapter 7: Making Decisions

Making Simple Decisions Using the if Statement

Understanding the if statement

Using the if statement in an application

Choosing Alternatives Using the if...else Statement

Understanding the if...else statement

Using the if...else statement in an application

Using the if...elif statement in an application

Using Nested Decision Statements

Using multiple if or if...else statements

Combining other types of decisions

Chapter 8: Performing Repetitive Tasks

Processing Data Using the for Statement

Understanding the for statement

Creating a basic for loop

Controlling execution with the break statement

Controlling execution with the continue statement

Controlling execution with the pass clause

Controlling execution with the else statement

Processing Data Using the while Statement

Understanding the while statement

Using the while statement in an application

Nesting Loop Statements

Chapter 9: Dealing with Errors

Knowing Why Python Doesn’t Understand You

Considering the Sources of Errors

Classifying when errors occur

Distinguishing error types

Catching Exceptions

Basic exception handling

Handling more specific to less specific exceptions

Nested exception handling

Raising Exceptions

Raising exceptions during exceptional conditions

Passing error information to the caller

Creating and Using Custom Exceptions

Using the finally Clause

Part III: Performing Common Tasks

Chapter 10: Interacting with Modules

Creating Code Groupings

Importing Modules

Using the import statement

Using the from...import statement

Finding Modules on Disk

Viewing the Module Content

Using the Python Module Documentation

Opening the pydoc application

Using the quick-access links

Typing a search term

Viewing the results

Chapter 11: Working with Strings

Understanding That Strings Are Different

Defining a character using numbers

Using characters to create strings

Creating Stings with Special Characters

Selecting Individual Characters

Slicing and Dicing Strings

Locating a Value in a String

Formatting Strings

Chapter 12: Managing Lists

Organizing Information in an Application

Defining organization using lists

Understanding how computers view lists

Creating Lists

Accessing Lists

Looping through Lists

Modifying Lists

Searching Lists

Sorting Lists

Working with the Counter Object

Chapter 13: Collecting All Sorts of Data

Understanding Collections

Working with Tuples

Working with Dictionaries

Creating and using a dictionary

Replacing the switch statement with a dictionary

Creating Stacks Using Lists

Working with queues

Working with deques

Chapter 14: Creating and Using Classes

Understanding the Class as a Packaging Method

Considering the Parts of a Class

Creating the class definition

Considering the built-in class attributes

Working with methods

Working with constructors

Working with variables

Using methods with variable argument lists

Overloading operators

Creating a Class

Using the Class in an Application

Extending Classes to Make New Classes

Building the child class

Testing the class in an application

Part IV: Performing Advanced Tasks

Chapter 15: Storing Data in Files

Understanding How Permanent Storage Works

Creating Content for Permanent Storage

Creating a File

Reading File Content

Updating File Content

Deleting a File

Chapter 16: Sending an E-Mail

Understanding What Happens When You Send E-mail

Viewing e-mail as you do a letter

Defining the parts of the envelope

Defining the parts of the letter

Creating the E-mail Message

Working with a text message

Working with an HTML message

Seeing the E-mail Output

Part V: The Part of Tens

Chapter 17: Ten Amazing Programming Resources

Working with the Python Documentation Online

Using the LearnPython.org Tutorial

Performing Web Programming Using Python

Getting Additional Libraries

Creating Applications Faster Using an IDE

Checking Your Syntax with Greater Ease

Using XML to Your Advantage

Getting Past the Common Python Newbie Errors

Understanding Unicode

Making Your Python Application Fast

Chapter 18: Ten Ways to Make a Living with Python

Working in QA

Becoming the IT Staff for a Smaller Organization

Performing Specialty Scripting for Applications

Administering a Network

Teaching Programming Skills

Helping People Decide on Location

Performing Data Mining

Interacting with Embedded Systems

Carrying Out Scientific Tasks

Performing Real-Time Analysis of Data

Chapter 19: Ten Interesting Tools

Tracking Bugs with Roundup Issue Tracker

Creating a Virtual Environment Using VirtualEnv

Installing Your Application Using PyInstaller

Building Developer Documentation Using pdoc

Developing Application Code Using Komodo Edit

Debugging Your Application Using pydbgr

Entering an Interactive Environment Using IPython

Testing Python Applications Using PyUnit

Tidying Your Code Using Isort

Providing Version Control Using Mercurial

Chapter 20: Ten Libraries You Need to Know About

Developing a Secure Environment Using PyCrypto

Interacting with Databases Using SQLAlchemy

Seeing the World Using Google Maps

Adding a Graphical User Interface Using TkInter

Providing a Nice Tabular Data Presentation Using PrettyTable

Enhancing Your Application with Sound Using PyAudio

Manipulating Images Using PyQtGraph

Locating Your Information Using IRLib

Creating an Interoperable Java Environment Using JPype

Accessing Local Network Resources Using Twisted Matrix

Accessing Internet Resources Using Libraries

About the Author

Cheat Sheet

Guide

Table of Contents

Begin Reading

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Introduction

Quick! Which programming language will get you up and running writing applications on every popular platform around? Give up? Yes, it’s Python. The amazing thing about Python is that you really can write an application on one platform and use it on every other platform that you need to support. Unlike the other programming languages that promised to provide platform independence, Python really does make that independence possible. In this case, the promise is as good as the result you get.

Python emphasizes code readability and a concise syntax that lets you write applications using fewer lines of code than other programming languages require. In addition, because of the way Python works, you find it used in all sorts of fields that are filled with nonprogrammers. Some people view Python as a scripted language, but it really is so much more. (Chapter provides you with just an inkling of the occupations that rely on Python to make things work.)