Miki Tebeka - Pandas Brain Teasers: Exercise Your Mind

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Preface

Pandas is a great library. I have used it in many projects, and it alwaysdelivers. Like any big project, the Pandas developers had to make some designdecisions that at times seem surprising. This book uses these quirks as ateaching opportunity. By understanding the gaps in your knowledge, youllbecome better at what you do.

Theres a lot of research showing that people who make mistakes during thelearning process learn better than people who dont. If you use this approachwhen fixing bugs, youll find you enjoy bug hunting more and become a betterdeveloper after each bug you fix.

These teasers will help you avoid mistakes. Some of the teasers are from my ownexperience shipping bugs to production and some are from others doing the same.

Teasers are fun! We geeks love to solve puzzles. You can also use these teasersto impress your coworkers, have knowledge competitions, and become bettertogether.

Many of these brain teasers are from quizzes I gave at conferences andmeetups. Ive found that people highly enjoy them, and they tend to livenup the room.

At the beginning of each chapter, Ill show you a short Python program withPandas code in it and ask you to guess the output. These are the possible answers:

• Syntax error
• Exception
• Some output (e.g., [1 2 3] )

Versions
	Im using Python version 3.8.3 and Pandas version 1.0.5. The output might change in future versions.

Before moving on to the answer and the explanation, go ahead and guessthe output. After guessing, I encourage you to run the codeand see the output yourself; only then proceed to read the solution andthe explanation. Ive been teaching programming for many years andfound this course of action to be highly effective.

About the Author

Miki Tebeka has a B.Sc. in computer science from Ben GurionUniversity. He also studied there toward an M.Sc. in computationallinguistics.