The Web is awash in Ruby code that is now virtually impossible to change or extend. This text helps you solve that problem by using powerful real-world object-oriented design techniques, which it thoroughly explains using simple and practical Ruby examples. Sandi Metz has distilled a lifetime of conversations and presentations about object-oriented design into a set of Ruby-focused practices for crafting manageable, extensible, and pleasing code. She shows you how to build new applications that can survive success and repair existing applications that have become impossible to change. Each technique is illustrated with extended examples, all downloadable from the companion Web site, poodr.info. The first title to focus squarely on object-oriented Ruby application design, Practical Object-Oriented Design in Ruby will guide you to superior outcomes, whatever your previous Ruby experience. Novice Ruby programmers will find specific rules to live by; intermediate Ruby programmers will find valuable principles they can flexibly interpret and apply; and advanced Ruby programmers will find a common language they can use to lead development and guide their colleagues. This guide will help you Understand how object-oriented programming can help you craft Ruby code that is easier to maintain and upgrade Decide what belongs in a single Ruby class Avoid entangling objects that should be kept separate Define flexible interfaces among objects Reduce programming overhead costs with duck typing Successfully apply inheritance Build objects via composition Design cost-effective tests Solve common problems associated with poorly designed Ruby code

    Topics are broken down into three major conceptual pieces: Virtualization, Concurrency, and Persistence. Includes all major components of modern systems including scheduling, virtual memory management, disk subsystems and I/O, file systems, and even a short introduction to distributed systems.

    You might think the problem is your brain. It seems to have a mind of its own, a mind that doesn't always want to take in the dry, technical stuff you're forced to study. The fact is your brain craves novelty. It's constantly searching, scanning, waiting for something unusual to happen. After all, that's the way it was built to help you stay alive. It takes all the routine, ordinary, dull stuff and filters it to the background so it won't interfere with your brain's real work--recording things that matter. How does your brain know what matters? It's like the creators of the Head First approach say, suppose you're out for a hike and a tiger jumps in front of you, what happens in your brain? Neurons fire. Emotions crank up. Chemicals surge. That's how your brain knows.And that's how your brain will learn Java. Head First Java combines puzzles, strong visuals, mysteries, and soul-searching interviews with famous Java objects to engage you in many different ways. It's fast, it's fun, and it's effective. And, despite its playful appearance, Head First Java is serious stuff: a complete introduction to object-oriented programming and Java. You'll learn everything from the fundamentals to advanced topics, including threads, network sockets, and distributed programming with RMI. And the new. second edition focuses on Java 5.0, the latest version of the Java language and development platform. Because Java 5.0 is a major update to the platform, with deep, code-level changes, even more careful study and implementation is required. So learning the Head First way is more important than ever. If you've read a Head First book, you know what to expect--a visually rich format designed for the way your brain works. If you haven't, you're in for a treat. You'll see why people say it's unlike any other Java book you've ever read.By exploiting how your brain works, Head First Java compresses the time it takes to learn and retain--complex information. Its unique approach not only shows you what you need to know about Java syntax, it teaches you to think like a Java programmer. If you want to be bored, buy some other book. But if you want to understand Java, this book's for you.

    These topics lie at the heart of many exciting areas of contemporary science and engineering - communication, signal processing, data mining, machine learning, pattern recognition, computational neuroscience, bioinformatics, and cryptography. This textbook introduces theory in tandem with applications. Information theory is taught alongside practical communication systems, such as arithmetic coding for data compression and sparse-graph codes for error-correction. A toolbox of inference techniques, including message-passing algorithms, Monte Carlo methods, and variational approximations, are developed alongside applications of these tools to clustering, convolutional codes, independent component analysis, and neural networks. The final part of the book describes the state of the art in error-correcting codes, including low-density parity-check codes, turbo codes, and digital fountain codes -- the twenty-first century standards for satellite communications, disk drives, and data broadcast. Richly illustrated, filled with worked examples and over 400 exercises, some with detailed solutions, David MacKay's groundbreaking book is ideal for self-learning and for undergraduate or graduate courses. Interludes on crosswords, evolution, and sex provide entertainment along the way. In sum, this is a textbook on information, communication, and coding for a new generation of students, and an unparalleled entry point into these subjects for professionals in areas as diverse as computational biology, financial engineering, and machine learning.

    You d be up to your neck in normal forms before you even had a chance to wade. When Michael J. Hernandez needed a database design book to teach mere mortals like himself, there were none. So he began a personal quest to learn enough to write one. And he did.Now in its Second Edition, Database Design for Mere Mortals is a miracle for today s generation of database users who don t have the background -- or the time -- to learn database design the hard way. It s also a secret pleasure for working pros who are occasionally still trying to figure out what they were taught.Drawing on 13 years of database teaching experience, Hernandez has organized database design into several key principles that are surprisingly easy to understand and remember. He illuminates those principles using examples that are generic enough to help you with virtually any application.Hernandez s goals are simple. You ll learn how to create a sound database structure as easily as possible. You ll learn how to optimize your structure for efficiency and data integrity. You ll learn how to avoid problems like missing, incorrect, mismatched, or inaccurate data. You ll learn how to relate tables together to make it possible to get whatever answers you need in the future -- even if you haven t thought of the questions yet.If -- as is often the case -- you already have a database, Hernandez explains how to analyze it -- and leverage it. You ll learn how to identify new information requirements, determine new business rules that need to be applied, and apply them.Hernandez starts with an introduction to databases, relational databases, and the idea and objectives of database design. Next, you ll walk through the key elements of the database design process: establishing table structures and relationships, assigning primary keys, setting field specifications, and setting up views. Hernandez s extensive coverage of data integrity includes a full chapter on establishing business rules and using validation tables.Hernandez surveys bad design techniques in a chapter on what not to do -- and finally, helps you identify those rare instances when it makes sense to bend or even break the conventional rules of database design.There s plenty that s new in this edition. Hernandez has gone over his text and illustrations with a fine-tooth comb to improve their already impressive clarity. You ll find updates to reflect new advances in technology, including web database applications. There are expanded and improved discussions of nulls and many-to-many relationships; multivalued fields; primary keys; and SQL data type fields. There s a new Quick Reference database design flowchart. A new glossary. New review questions at the end of every chapter.Finally, it s worth mentioning what this book isn t. It isn t a guide to any specific database platform -- so you can use it whether you re running Access, SQL Server, or Oracle, MySQL or PostgreSQL. And it isn t an SQL guide. (If that s what you need, Michael J. Hernandez has also coauthored the superb SQL Queries for Mere Mortals). But if database design is what you need to learn, this book s worth its weight in gold. Bill CamardaBill Camarda is a consultant, writer, and web/multimedia content developer. His 15 books include Special Edition Using Word 2000 and Upgrading & Fixing Networks for Dummies, Second Edition.

    Today, twenty million people worldwide are surfing the Net. Where Wizards Stay Up Late is the exciting story of the pioneers responsible for creating the most talked about, most influential, and most far-reaching communications breakthrough since the invention of the telephone. In the 1960's, when computers where regarded as mere giant calculators, J.C.R. Licklider at MIT saw them as the ultimate communications devices. With Defense Department funds, he and a band of visionary computer whizzes began work on a nationwide, interlocking network of computers. Taking readers behind the scenes, Where Wizards Stay Up Late captures the hard work, genius, and happy accidents of their daring, stunningly successful venture.

    It’s an exploration of making, but it’s also a permission slip of sorts from me to you. Permission to grab hold of the things you’re interested in, that fascinate you, and to dive deeper into them to see where they lead you. Through stories from forty-plus years of making and molding, building and break­ing, along with the lessons I learned along the way, this book is meant to be a toolbox of problem solving, complete with a shop’s worth of notes on the tools, techniques, and materials that I use most often. Things like: In Every Tool There Is a Hammer—don’t wait until everything is perfect to begin a project, and if you don’t have the exact right tool for a task, just use whatever’s handy; Increase Your Loose Tolerance—making is messy and filled with screwups, but that’s okay, as creativity is a path with twists and turns and not a straight line to be found; Use More Cooling Fluid—it prolongs the life of blades and bits, and it prevents tool failure, but beyond that it’s a reminder to slow down and reduce the fric­tion in your work and relationships; Screw Before You Glue—mechanical fasteners allow you to change and modify a project while glue is forever but sometimes you just need the right glue, so I dig into which ones will do the job with the least harm and best effects. This toolbox also includes lessons from many other incredible makers and creators, including: Jamie Hyneman, Nick Offerman, Pixar director Andrew Stanton, Oscar-winner Guillermo del Toro, artist Tom Sachs, and chef Traci Des Jardins. And if everything goes well, we will hopefully save you a few mistakes (and maybe fingers) as well as help you turn your curiosities into creations. I hope this book serves as “creative rocket fuel” (Ed Helms) to build, make, invent, explore, and—most of all—enjoy the thrills of being a creator.

    Courses and books on basic statistics rarely cover the topic from a data science perspective. This practical guide explains how to apply various statistical methods to data science, tells you how to avoid their misuse, and gives you advice on what's important and what's not.Many data science resources incorporate statistical methods but lack a deeper statistical perspective. If you're familiar with the R programming language, and have some exposure to statistics, this quick reference bridges the gap in an accessible, readable format.With this book, you'll learn:Why exploratory data analysis is a key preliminary step in data scienceHow random sampling can reduce bias and yield a higher quality dataset, even with big dataHow the principles of experimental design yield definitive answers to questionsHow to use regression to estimate outcomes and detect anomaliesKey classification techniques for predicting which categories a record belongs toStatistical machine learning methods that "learn" from dataUnsupervised learning methods for extracting meaning from unlabeled data

    The acoustic patches are based on harmonic analysis and are exceedingly close to the real instruments.An included CD contains the new SCB VSTi softsynth and audio samples for synthesizer calibration as well as a full album of electronica.

    With an almost unlimited range of input and output add-ons, sensors, indicators, displays, motors, and more, the Arduino offers you countless ways to create devices that interact with the world around you.In Arduino Workshop, you'll learn how these add-ons work and how to integrate them into your own projects. You'll start off with an overview of the Arduino system but quickly move on to coverage of various electronic components and concepts. Hands-on projects throughout the book reinforce what you've learned and show you how to apply that knowledge. As your understanding grows, the projects increase in complexity and sophistication.Among the book's 65 projects are useful devices like:A digital thermometer that charts temperature changes on an LCD A GPS logger that records data from your travels, which can be displayed on Google Maps A handy tester that lets you check the voltage of any single-cell battery A keypad-controlled lock that requires a secret code to open You'll also learn to build Arduino toys and games like:An electronic version of the classic six-sided die A binary quiz game that challenges your number conversion skills A motorized remote control tank with collision detection to keep it from crashingArduino Workshop will teach you the tricks and design principles of a master craftsman. Whatever your skill level, you'll have fun as you learn to harness the power of the Arduino for your own DIY projects.

    The show celebrates design and architecture in all of its functional glory and accidental absurdity, with intriguing tales of both designers and the people impacted by their designs.Now, in The 99% Invisible City: A Field Guide to Hidden World of Everyday Design, host Roman Mars and coauthor Kurt Kohlstedt zoom in on the various elements that make our cities work, exploring the origins and other fascinating stories behind everything from power grids and fire escapes to drinking fountains and street signs. With deeply researched entries and beautiful line drawings throughout, The 99% Invisible City will captivate devoted fans of the show and anyone curious about design, urban environments, and the unsung marvels of the world around them.

    Reveals how to run an online business profitably in spite of the Internet's inherently free culture, disseminating the principles of a ''priceless economy'' in six categories that pertain to advertising, labor exchange, and advanced-version fees.

    You'll learn how to:Read and write files efficiently Use signals, clocks, and timers Create processes and execute programs Write secure programs Write multithreaded programs using POSIX threads Build and use shared libraries Perform interprocess communication using pipes, message queues, shared memory, and semaphores Write network applications with the sockets API While The Linux Programming Interface covers a wealth of Linux-specific features, including epoll, inotify, and the /proc file system, its emphasis on UNIX standards (POSIX.1-2001/SUSv3 and POSIX.1-2008/SUSv4) makes it equally valuable to programmers working on other UNIX platforms.The Linux Programming Interface is the most comprehensive single-volume work on the Linux and UNIX programming interface, and a book that's destined to become a new classic.Praise for The Linux Programming Interface "If I had to choose a single book to sit next to my machine when writing software for Linux, this would be it." —Martin Landers, Software Engineer, Google "This book, with its detailed descriptions and examples, contains everything you need to understand the details and nuances of the low-level programming APIs in Linux . . . no matter what the level of reader, there will be something to be learnt from this book." —Mel Gorman, Author of Understanding the Linux Virtual Memory Manager "Michael Kerrisk has not only written a great book about Linux programming and how it relates to various standards, but has also taken care that bugs he noticed got fixed and the man pages were (greatly) improved. In all three ways, he has made Linux programming easier. The in-depth treatment of topics in The Linux Programming Interface . . . makes it a must-have reference for both new and experienced Linux programmers." —Andreas Jaeger, Program Manager, openSUSE, Novell "Michael's inexhaustible determination to get his information right, and to express it clearly and concisely, has resulted in a strong reference source for programmers. While this work is targeted at Linux programmers, it will be of value to any programmer working in the UNIX/POSIX ecosystem." —David Butenhof, Author of Programming with POSIX Threads and Contributor to the POSIX and UNIX Standards ". . . a very thorough—yet easy to read—explanation of UNIX system and network programming, with an emphasis on Linux systems. It's certainly a book I'd recommend to anybody wanting to get into UNIX programming (in general) or to experienced UNIX programmers wanting to know 'what's new' in the popular GNU/Linux system." —Fernando Gont, Network Security Researcher, IETF Participant, and RFC Author ". . . encyclopedic in the breadth and depth of its coverage, and textbook-like in its wealth of worked examples and exercises. Each topic is clearly and comprehensively covered, from theory to hands-on working code. Professionals, students, educators, this is the Linux/UNIX reference that you have been waiting for." —Anthony Robins, Associate Professor of Computer Science, The University of Otago "I've been very impressed by the precision, the quality and the level of detail Michael Kerrisk put in his book. He is a great expert of Linux system calls and lets us share his knowledge and understanding of the Linux APIs." —Christophe Blaess, Author of Programmation systeme en C sous Linux ". . . an essential resource for the serious or professional Linux and UNIX systems programmer. Michael Kerrisk covers the use of all the key APIs across both the Linux and UNIX system interfaces with clear descriptions and tutorial examples and stresses the importance and benefits of following standards such as the Single UNIX Specification and POSIX 1003.1." —Andrew Josey, Director, Standards, The Open Group, and Chair of the POSIX 1003.1 Working Group "What could be better than an encyclopedic reference to the Linux system, from the standpoint of the system programmer, written by none other than the maintainer of the man pages himself? The Linux Programming Interface is comprehensive and detailed. I firmly expect it to become an indispensable addition to my programming bookshelf." —Bill Gallmeister, Author of POSIX.4 Programmer's Guide: Programming for the Real World ". . . the most complete and up-to-date book about Linux and UNIX system programming. If you're new to Linux system programming, if you're a UNIX veteran focused on portability while interested in learning the Linux way, or if you're simply looking for an excellent reference about the Linux programming interface, then Michael Kerrisk's book is definitely the companion you want on your bookshelf." —Loic Domaigne, Chief Software Architect (Embedded), Corpuls.com

    Hardcover published by Quadragle/The New York Times Book Co., third printing, August 1977, copyright 1975.

    Where to begin? Head First Android Development will help you get your first application up and running in no time with the Android SDK and Eclipse plug-in. You'll learn how to design for devices with a variety of different screen sizes and resolutions, along with mastering core programming and design principles that will make your app stand out.Whether you're a seasoned iPhone developer who wants to jump into the the Android Market, or someone with previous programming skills but no mobile apps in your resume, this book offers a complete learning experience for creating eye-catching, top-selling Android applications.You'll learn how to:Install the Android SDK and Eclipse plug-in and get started building appsAdd buttons, edit text fields, and build your own navigation options in the Android menuCustomize the look of your app with theming and adding image resourcesUse Android's content provider mechanism to add images and contact information to an app, and establish permissions for their useWork with the Android devices' camera, GPS, and accelerometerExperiment with different Android emulator configurations to simulate different devices with a variety of screen sizesOptimize, test, and distribute your application in the Android MarketWe think your time is too valuable to waste struggling with new concepts. Using the latest research in cognitive science and learning theory to craft a multi-sensory learning experience, Head First Android Development uses a visually rich format designed for the way your brain works, not a text-heavy approach that puts you to sleep.