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Parallel R by Stephen Weston, Q. Ethan McCallum

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Using Code Examples

This book is here to help you get your job done. In general, you may use the code in this book in your programs and documentation. You do not need to contact us for permission unless you’re reproducing a significant portion of the code. For example, writing a program that uses several chunks of code from this book does not require permission. Selling or distributing a CD-ROM of examples from O’Reilly books does require permission. Answering a question by citing this book and quoting example code does not require permission. Incorporating a significant amount of example code from this book into your product’s documentation does require permission.

We appreciate, but do not require, attribution. An attribution usually includes the title, author, publisher, and ISBN. For example: “Parallel R by Q. Ethan McCallum and Stephen Weston (O'Reilly). Copyright 2012 Q. Ethan McCallum and Stephen Weston, 978-1-449-30992-3.”

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There are only two names on the cover, but a host of people made this book possible.

We would like to thank the entire O’Reilly team for their efforts. They provided such a smooth process that we were able to focus on just the writing. A special thanks goes to our editors, Mike Loukides and Meghan Blanchette, for their guidance and support.

We would also like to thank our review team. The following people generously dedicated their time and energy to read this book in its early state, and their feedback helped shape the text into the finished product you’re reading now:

Robert Bjornson
Nicholas Carriero
Jonathan Seidman
Paul Teetor
Ramesh Venkataramaiah
Jed Wing

Any errors you find in this book belong to us, the authors.

Most of all we thank you, the reader, for your interest in this book. We set out to create the guidebook we wish we’d had when we first tried to give R that parallel, distributed boost. R work is research work, best done with minimal distractions. We hope these chapters help you get up to speed quickly, so you can get R to do what you need with minimal detour from the task at hand.

Q. Ethan McCallum

“You like math? Oh, you need to talk to Mike. Let me introduce you.” I didn’t realize it at the time, but those words were the start of this project. Really. A chance encounter with Mike Loukides led to emails and phone calls and, before I knew it, we’d laid the groundwork for a new book. So first and foremost, a hearty thanks to Betsy and Laurel, who made my connection to Mike.

Conversations with Mike led me to my co-author, Steve Weston. I’m pleased and flattered that he agreed to join me on this adventure.

Thanks as well to the gang at Cafe les Deux Chats, for providing a quiet place to work.

Stephen Weston

This was my first book project, so I’d like to thank my co-author and editors for putting up with my freshman confusion and mistakes. They were very gracious throughout the project.

I’m very grateful to Nick, Rob, and Jed for taking the time to read my chapters and help me not to make a fool of myself. I also want to thank my wife Diana and daughter Erica for proofreading material that wasn’t on their preferred reading lists.

Finally, I’d like to thank all the authors of the packages that we discuss in this book. I had a lot of fun reading the source for all three of the packages that I wrote about. In particular, I’ve always loved the snow source code, which I studied when first learning to program in R.

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