Stuart Reges - Building Python Programs

First Edition

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The authors and publisher of this book have used their best efforts in preparing this book. These efforts include the development, research, and testing of the theories and programs to determine their effectiveness. The authors and publisher make no warranty of any kind, expressed or implied, with regard to these programs or to the documentation contained in this book. The authors and publisher shall not be liable in any event for incidental or consequential damages in connection with, or arising out of, the furnishing, performance, or use of these programs.

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Library of Congress Cataloging-in-Publication Data

Names: Reges, Stuart, author. | Stepp, Martin, author. | Obourn, Allison, author.

Title: Building Python programs / Stuart Reges, University of Washington, Marty Stepp, Stanford University, Allison Obourn, University of Arizona.

Description: First edition. | New York, NY : Pearson, [2019] | Includes index.

Identifiers: LCCN 2018028848| ISBN 9780135205983 | ISBN 0135205980

Subjects: LCSH: Python (Computer program language)

Classification: LCC QA76.73.P98 R445 2019 | DDC 005.13/3dc23

LC record available at https://lccn.loc.gov/2018028848

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ISBN 10: 0-13-520598-0

ISBN 13: 978-0-13-520598-3

The Python programming language has become enormously popular in recent years. Many people are impressed with how quickly you can learn Pythons simple and intuitive syntax and that has led many users to create popular libraries. Python was designed by Guido van Rossum who has been affectionaly dubbed Benevolent Dictator For Life (BDFL) by the Python community. He has said that he chose the name Python because he was in a slightly irreverent mood and that he is a big fan of Monty Pythons Flying Circus (a British comedy show). Who wouldnt want to learn a programming language named after a group of comedians?

Our new Building Python Programs text is designed for use in a first course in computer science. We have class-tested it with hundreds of undergraduates at the University of Arizona, most of whom were not computer science majors. This textbook is based on our previous text, Building Java Programs, now in its fourth edition. The Java text has proven effective in our class testing with thousands of students including our own at the University of Washington since 2007.

Introductory computer science courses have a long history at many universities of being killer courses with high failure rates. But as Douglas Adams says in The Hitchhikers Guide to the Galaxy, Dont panic. Students can master this material if they can learn it gradually.

Python has many attributes that make it an appealing language for a first computer science course. It has a simple and concise yet powerful syntax that makes it pleasant to learn and great for writing many common programs. A student can write their first Python program with only a single line of code, as opposed to several lines in most other languages such as Java or C++. Python includes a built-in interpreter and read-evaluate-print loop (REPL) for quickly running and testing code, encouraging students to test and explore the language. Python also offers a rich set of libraries that students can use for graphics, animation, math, scientific computing, games, and much more. This text has been built from the start for Python 3, the most modern version of the language as of this writing, and it embraces the modern features and idioms of that version of the language.

Our teaching materials are based on a back to basics approach that focuses on procedural programming and program decomposition. This is also called the objects later approach, as opposed to the objects early approach taught in some schools. We know from years of experience that a broad range of scientists, engineers, and others can learn how to program in a procedural manner. Once we have built a solid foundation of procedural techniques, we turn to object-oriented programming. By the end of the text, students will have learned about both styles of programming.

The following are the key features of our approach and materials:

• Focus on problem solving. Many textbooks focus on language details when they introduce new constructs. We focus instead on problem solving. What new problems can be solved with each construct? What pitfalls are novices likely to encounter along the way? What are the most common ways to use a new construct?

• Emphasis on algorithmic thinking. Our procedural approach allows us to emphasize algorithmic problem solving: breaking a large problem into smaller problems, using pseudocode to refine an algorithm, and grappling with the challenge of expressing a large program algorithmically.