Japanese Translation Project for Open Data Structures


  • Translating Open Data Structures, open free textbook on data structure
  • Planning to write sample codes in Ruby, and re-export the Ruby edition into English
  • Looking for assistance, feedbacks/proof-reading/revision or funds, to improve the translation quality

Translation project of Open Data Structures

Have you heard of a project called Open Data Structures? It was started by Mr. Pat Morin, and it offers textbooks about data structures, the first subject that any computer science students will learn, for free.

Since it is “the first subject” taught to “every student” “in any university”, it is:

  • necessary in many computer science fields
  • used by everyone
  • a universal subject.

This directly shows the meaningfulness of this project and of the field itself.

I learned about data structures in the first semester of my university course using this textbook. It was only last month that I realized that there wasn’t a Japanese version of this textbook yet, and contacted Pat. He welcomed my idea of translating it, and as far as he knows he isn’t aware of anyone translating it yet (If there is someone translating this book, please let me know.). This is how I decided to translate the book that once guided me into this attractive field.

Why translation?

First, is the Japanese translation required?

Personally, I find I can read Japanese much faster than reading English. However, when reading a technical document, I usually avoid translation. The quality of translation is sometimes not so high, and hence I often feel difficulty understanding the content.

This textbook is a basic introduction to computer science. The required knowledge is at most, high school level math, although it is better to have some experiences in programming to enjoy the content. If there is a free introduction-level textbook written in Japanese, the field would be further accessible and may increase the number of programmers who can enjoy programming and can write efficient codes.

Few countries have university-level textbooks written in their native languages. One may insist that earlier experience to read texts in English is required because students have to read more professional texts in English in the near future. I also had a hesitation to read texts in English when entering university, though I got used to reading English-textbooks during entrance exam preparations. It is important to remove this resistance to English as soon as possible in order to open vast amounts of accessible knowledge for students. What supports reluctance to English of Japanese students may be the rich cultural environment which enables them to read textbooks in their native language even after entering university.

This textbook is placed at an entrance to mediate between students and professional worlds. Required knowledge for this book is adjusted to the minimum, but adding English skills to the requirement may lead to a narrower range of possible readers. I believe that it is without doubt admirable to have an option to read well-written beginner’s guides in the native language.

The length of this book is about 300 pages, and the contents are well-explained while it contains a practical set of subjects. There are full-scale textbooks and some of them are translated in Japanese. These are brilliant textbooks for both beginners and more advanced learners, and I also peruse them repeatedly even now. The quality of translation of at least two books I have, Algorithm Design and Introduction to Algorithms, is also good. But, they are not easy to read through or buy since its length is about 1000 pages of large-scale paper and its price is about 10,000 yen. The purpose of this translation is making the introduction textbook accessible for free for students who will read more serious professional textbooks as listed above.

Development of Ruby edition

I have another idea for this project.

Open Data Structures now has three editions, pseudo-code edition, C++ edition, and Java edition. I’m planning to write sample codes in Ruby and add the Ruby edition.

I learned programming for the first time in Ruby, and the language has always been my favorite. In Google Summer of Code last year, I learned so much about the language and its implementation thanks to Ruby developers. It was a really exciting experience, and so I want to give back something to the Ruby community.

In short, I will develop a Ruby edition of ODS in this project. I’m concentrating on translation for now, so I’m putting pseudo-codes as a placeholder. If the Ruby edition is written well, I want to re-export it to the English version of the book in the future.


I’ve been working for a month, and have already reached chapter 9 of the 14 chapters there are. The alpha version, the rough translation of the whole texts, will finish on July 20th in my schedule.

Version 1.0 with finished structures and sample Ruby codes attached would be uploaded on the first half of August this year.

Call for assistance

As I said, translated texts often become hard to read. We surely don’t want that to happen to this book, so we are asking those who appreciate the value of this book to help so that we can publish the best version.

The translation process is already in its middle stage, and it’s not much of a hassle for me to continue. But I’m not a master of English let alone a professional translator. My priority is finishing the first draft with my limited spare time. Therefore the quality of this first draft might not be ideal, and that’s why I’m asking for support to maintain the quality of this textbook.

I’m currently considering the following three options:

  • casual feedbacks: Readers could point out flaws in the translations and send me a feedback through Github, e-mail, Twitter or other means.
  • taking some responsibility: For those who can invest some time into this project, feedbacks could be given in the form of proofreading, revisions and reviews for particular chapters of the text.
  • financial support: I also need some financial support to fund some professional feedback for the book. For example, I can ask several professionals to review and revise the whole text for approximately 100,000 yen (if I pay 0.5 yen per Japanese character.) The fund will be raised through cloud funding. Apart from directly giving, you can also help by spreading the news.

If I could run an entire check using the second and the third option, I can ensure the quality of the textbook. I will thank those who helped this project in the acknowledgement section (maybe a hot idea to sell advertisement columns through cloud funding to enable imprinting into promising future programmers😏).