Customer Reviews

Discrete Mathematics (6th Edition) (Jk Computer Science and Mathematics)

5 star:		(6)
4 star:		(4)
3 star:		(5)
2 star:		(6)
1 star:		(33)

 

 

I taught a discrete math course in a major US university based on this book. Having been adopted by most US universities over the years, there was no choice.

There is no clear line of exposition in this book. Knowing what it should be about, it is repulsive to see how unstructured the content is, and how truly beautiful mathematics is made ugly beyond recognition. There exist far more insightful and shorter proofs than many of those given here.

Instead of developing a choice of key topics cleanly, transparently, and in detail, a large collection of loosely related facts are glued together in a supremely uninspired way. Some topics which are far too advanced for this level of exposition are mentioned over several pages, without any rigorous treatment, of course, while many important topics are left away that could have been included.

The elegance quotient of this book is zero. Students should learn how to present a proof. They should learn to pin down the key ideas, and to write a proof in the clearest and most transparent language as possible. Whoever takes this text as her/his stylistic guide will do her/himself great harm.

I am a research mathematician. It is my job to know precisely what good mathematics looks like, and also to know when something smells really bad. Believe me, this one smells beyond rotten.

There are beautiful treatises on the same material on the internet, and one may also look at a small book for roughly 10 $ by Balakrishnan, from Dover publishers (available on Amazon, "Introductory discr math"). It doesn't contain as much material, but is so much more worth the money. A diligently made choice of topics is presented in clear, concise words that are to the point.

There is also the book by Laszlo Lovasz, a master of the field. The clarity, inspiration and transparence of the exposition is absolutely exemplary. The paperback version costs around 35$ on Amazon.

If you read those texts, you will understand what Johnsonbaugh is trying to put into clumsy words, illiterate proofs, boring examples, and silly pictures.

What really hurts me is to see students, some of whom are not rich, paying 100 $ for this convoluted mess.

My main message to every student using Mr. Johnsonbaugh's oeuvre is: If you don't understand this mess, it may be because you have mathematical talent. Go and look for a better, cheaper text. Save your time, it's not worth trying to figure out what the author intends to say.

Why must so many universities foist this abomination upon their CS students as a required text? Is there really nothing better available, or does Johnsonbaugh possess incriminating photos of every school's Dean of ENGR in the country?

This is, without a doubt, the WORST textbook I have EVER encountered -- in any subject. It might qualify as the worst textbook OF ALL TIME. Yes, it's really that horrible. It's verbose. It's dull. Many of the examples are longer than necessary (and more than occasionally, misleading). Like many texts on this topic, it features Solutions to Selected Exercises in the back, but what's the point in displaying the final answer to an involved problem if you don't demonstrate how you arrived at it? If you're going to print an answer, PLEASE provide us with the COMPLETE answer.

I have searched (largely in vain) for another text or two to use as study aids. If you're thinking about Schaum's, hang onto your money (Note to Schaum's: Why publish a separate book of "Solved Problems" if you're merely recycling the same examples from the Outlines book?). Susanna S. Epp's textbook is much better in most places -- most notably the section on graphs.

Bottom line: if your school adopts Johnsonbaugh as the required text for your course, hang onto your money and rely on your lecture notes. This book is a waste of trees.

This book epitomizes the common flaw in higher education today-expecting that an "expert in a field" makes them an "expert teacher". Bull. This book is written by someone who has decided to write a book 6 levels above the education of their readers just so they can prove a point at how smart they are. I'll bet Johnsonbaugh is the kind of guy that just stands at the board writing his notes that he could just give to you, just so he can hear the glory of his own voice. I have taken 4 semesters of calculus as an undergrad, as well as various science graduate courses and am LOST when reading this book. This book may be good for math "majors," but for people looking in other fields (Computer science, for example) it is terrible.

School administrators, take note: Find another book for your students. Just because this guy is an expert, doesn't mean he can come close to making everyone else one. Spend time studying the impact of this book, and you will see that this book is as effective in educating as a ruler to the knuckles.

Johnsonbaugh should stay where he belongs-in the lab, solving the world's math problems and leave teaching up to the teachers.

My university requires this book for the discrete mathematics course. I have to tell you, this book teaches you absolutely nothing! The author barely explains things. And when he does explain things, he explains them as if the person reading already has an indepth knowledge of advanced math. There is no explaination as to how he arrived at answers at the back of the book.
I actually have to buy another book because I got so frustrated trying to learn this, that I ripped the book almost into shreds. And its only been two weeks into the term! I'm contemplating emailing the author to tell him to quit writing textbooks because this one is horrible.

My recommendation is not to buy this book unless you have no other choice.

This book is terrible. I was able to breeze through calculus with few problems. But now I am in Discrete Mathematics with this....worthless...book. I am being nice by describing it that way, as I am currently, right now at the library and considering burning it. I have thrown my book across a room at least four times this semester, with many more fun-filled hours of confusion ahead. How am I supposed to understand the tough problems in this book when he feels that he does not need to complete the answers to the easy ones. I have heard that he is a great mathematician, but hey just because you can add numbers does not mean you can write about it.
This semester has been tough enough for me, but with this book I have been devastated. I just cannot understand where he gets the tough questions from, you know what I am talking about if you have tried them, and how he expects that a person who does not have years of experience in discrete mathematics can possibly figure them out. Must be easy and rewarding for him to explain the easy stuff. Hope he enjoys my 85 bucks, because I am hating this. I will not return my book this semester, I would not wish this pain on my worse enemy. At the end of this semester when all is said and done, I have two options:
1) light this book on fire to save on my heating bill (possible)
2)Drive up to DePaul University in Chicago meet with Johnsonbaugh, and give it back to him

The last option sounds better and better with every problem I "solve" in this book.
STOP DEFORESTATION DONT PRINT THIS BOOK ANYMORE

Warning!!! If you are trying to LEARN discrete math, buy a different book. It it is for class, MAKE SURE YOU GET A SUPPLEMENT BOOK. There are a couple of paperback books that can help. Unfortunatly the Author is also a Professor at my University, so buying it is a requirement.
-*- Excercises only have a hand full of answers, not every odd like every other math book.
-*- No detailed answers (working out excersise problems)
-*- Teaching examples may not apply to exercise problems.
-*- Overall, most confusing math (or any grad or undergrad level class) book I have used

This book is a required text used by the university I attend in an introductory discrete mathematics subject. I had little to no difficulty following the notes given during lectures, but when I wanted to brush up on/practice certain topics I found this book to be nothing more than confusing. I can only recommend buying a supplementary text if you find yourself doing a course on this topic and this being the required text.

I used this book last semester in my Discrete Mathematics class in Minnesota. This is by far the worst mathematics textbook I have ever seen. I was in the hospital for appendicitis and missed an entire week's worth of class. Usually this isn't a big deal, I would just read the text on my own. I think it is very telling that I could NOT understand what I was reading when I tried to catch up with what I missed in this class. I actually had to meet with the professor and he had to take time to go through each lesson with me. I have to believe there are better choices out there. I am begging professors to find a better and easier to understand book!

I have always held the belief (even as a mathematician who favors analysis) that math is suppose to be elegant. This book is anything but elegant. It currently resides in my dorm for the sole purpose of a clip-board so that I may lie on the carpet and work out problems from other texts. I had the unfortunate pleasure of suffering through two semesters of this book. The first semester (the first half of the book) was not bad given that we never referenced the text. The second semester was much worse given that most of the information in the course came directly from the text and its examples. If you are looking for a beginners discrete math book... look elsewhere. I can distinctly remember taking a course in precalculus and discrete mathematics my junior year of highschool in Maryland. That book was actually tollerable.

This textbook is good at explaining easy concepts like graphing, tree traversals, and simple algorithms. While I'm not knocking this fact, these things are so easy to understand you can pick them up using Google. Unfortunately, when it comes down to advanced topics of discrete math, the book is terribly weak.

By advanced topics, I mean things that you'll likely encounter in computer science theory. This is essentially what discrete math is for, so this is important. The discussions on recursion, analysis of computational complexity, recurrence relations, and especially proof by contradiction and induction are all too short, too abrupt, and too weak. Though examples are provided, they are too simple and do little to bring you to actual understanding of these difficult concepts. There are titanic tracts about cycles, paths, and all sorts of algorithms to deal with these. While interesting and often useful, this isn't what I was looking for. The author should really have focused more on the discrete math, leaving the interesting algorithms to data structure textbooks.

I should probably note here that I've already learned all of this material and was using this book as a reference. Even then, it was still difficult to figure out what the author was doing! I wouldn't even recommend the text to someone intending to use it purely for review, and would warn those with no knowledge of the subject to steer well clear.