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Why Don't Schools Teach Debugging?

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Re: Why Don't Schools Teach Debugging?

#121

Post by robertfw »

greenyoda wrote: post #115
wfunction wrote: post #28

Earlier quoted context omitted.

EE is all about intuition, really. If you don't have the intuition to approximate everything (I don't) then you just sink; there's no way to do everything exactly like is often possible in CS. It's even more important than how good you are at math, because the whole point of the skill is figuring out when you don't have to do a lot of math in the first place.

CS is also heavily reliant on intuition: - Picking the right architecture for a complex system out of a huge space of potential solutions (which have varying costs, performance, reliability, maintainability and complexity) requires a lot of intuition, developed over years of practice. There's no deterministic method that you can use to crank out the "right answer". - At a lower level, the same applies to choosing alg…

In addition, usually you are balancing those searches for optimal solutions against business deadlines, incomplete specs, and the need to make unknown changes in the future.

Re: Why Don't Schools Teach Debugging?

#122

Post by wolfgke »

blah32497 wrote: post #105
mandor wrote: post #61

Earlier quoted context omitted.

CS prof. here. We don't want to teach "tools" (e.g. IDE) because they are always changing. There is no point is knowing how to set up an IDE when the IDE will have a different GUI before the student graduates. We teach"unix tools" a bit more because they did not change much during the last decades. My goal is to teach "concepts" (which is hard) and use tools as examples of these concepts. Dealing with the specifics o…

I'm so glad you replied! I've heard versions of what you've said hundreds of times and honestly, you academics are missing the point! Yes, the particular tool you learn will become obsolete, but debugging between Eclipse, gdb, Visual Studio etc. is all basically the same. The knowledge you get is transferrable, just like they have a head start if you teach them C++ and they end up in a Java shop. Teach them tools tha…

> I really strongly encourage you to set up your students with IDEs. Have a few seminars on how to set up a Visual Studio environment, and how to debug a large codebase.

You can find lots of information about that using a search engine of your choice. Any student should be able to use Google. So there's no reason to waste teaching ressources for that purpose.

Re: Why Don't Schools Teach Debugging?

#123

Post by MichaelMoser123 »

mandor wrote: post #61
blah32497 wrote: post #11

I never knew this was a problem in EE, but I know for a fact it's a huge issue in CS. They don't want to teach any "tools" b/c CS professors find teaching people how to be good developers as beneath them. They honest to god think CS is an actually hard science on par with math and physics. You can sum up their attitude with: "It's not an associates degree goddamnit!" (even though it should be) Another source of reluc…

CS prof. here. We don't want to teach "tools" (e.g. IDE) because they are always changing. There is no point is knowing how to set up an IDE when the IDE will have a different GUI before the student graduates. We teach"unix tools" a bit more because they did not change much during the last decades. My goal is to teach "concepts" (which is hard) and use tools as examples of these concepts. Dealing with the specifics o…

For really big programs you can't use valgrind; valgrind causes significant performance hit and the system often starts to choke under the the memory load. Also GDB really alters the timing of things, so it is bad at timing/multithreading bugs.

Mostly what helps is working through the logs & traces / following through the code along as you pass through the traces; Use a needle and a steady hand ;-)

i guess that's what they should practice in school as part of learning the trade. On the other hand its a trade off - school needs to teach the general principles of programming, with regards to debugging it is hard to distill universally applicable principles; it all depends on what you are doing.

Here is my take:

- unit testing is cool, it allows to catch problems in isolation; so it would be useful to teach this as a discipline

- for most GUI programs and application logic the debugger is really helpful

- traces and log analysis as mentioned earlier as the last resort

Also they should teach how to formulate the problem, analyse problem source and ways of fixing a defect; here you have to understand the trade offs: when to choose a local fix, when is a local fix no longer appropriate; how to quickly test a fix - so that it does not break the system in any way.

If i remember correctly then some of that they do teach in software engineering courses.

Re: Why Don't Schools Teach Debugging?

#124

Post by wolfgke »

analog31 wrote: post #65
mandor wrote: post #61

Earlier quoted context omitted.

CS prof. here. We don't want to teach "tools" (e.g. IDE) because they are always changing. There is no point is knowing how to set up an IDE when the IDE will have a different GUI before the student graduates. We teach"unix tools" a bit more because they did not change much during the last decades. My goal is to teach "concepts" (which is hard) and use tools as examples of these concepts. Dealing with the specifics o…

Thanks for the comment. I agree that tools go obsolete quickly. But it occurs to me that debugging is both a set of tools but also a knack. I'm curious what you think about how to teach the knack.

How to teach the knack:

Write lots of code that uses the most sketchy language features available. The chance is high that soon you'll get code that doesn't work. Now go through each line (source code or assembly) using a debugger of your choice and get it to work again.

Do this until there is nothing that will scare you anymore.

Re: Why Don't Schools Teach Debugging?

#125

Post by mkartic »

blah32497 wrote: post #106
jarvic wrote: post #51

Earlier quoted context omitted.

>They don't want to teach any "tools" b/c CS professors find teaching people how to be good developers as beneath them. They honest to god think CS is an actually hard science on par with math and physics. Despite what you (and a lot developers that I've talked to) seem to think, CS is a hard science. However, CS and software development are not the same thing. Most CS programs are taught by professors who have resea…

"CS is a hard science" Hahaha. As someone who did a degree in physics, computer "science" is a joke when it comes to math. They took one of the easiest field of mathematics and rolled it in to a half-assed degree. Sure you learn some logic and some graph theory (yeah, lets try to avoid numbers as much as possible...) but it's not at a very high level. I seriously doubt CS professors are making significant contributio…

Why the bitterness against CS?

As jarvic says,

> However, CS and software development are not the same thing.

A lot of schools offer a separate degree in Software engineering as opposed to CS (or at least separate tracks). So the distinction is pretty clear. Where I studied, there are separate degrees for CS and IT. You seem to be fudging the two. Do you expect physics majors to be mechanical engineers automatically?

CS degrees teach you algorithms, not how to write code in Java. Doesn't matter what IDE/language you're using, bubble sort is going to be slower than quicksort for large lists.

Yes, unfortunately most people who do CS end up becoming IT drones. That's the nature of the industry, not the CS program's fault. As a matter of interest, what do most physics majors become? I'm sure there aren't enough professorships available.

Or in the words of E.W.Dijkstra: “Computer science is no more about computers than astronomy is about telescopes.”

Re: Why Don't Schools Teach Debugging?

#126

Post by Illotus »

wolfgke wrote: post #122
blah32497 wrote: post #105

Earlier quoted context omitted.

I'm so glad you replied! I've heard versions of what you've said hundreds of times and honestly, you academics are missing the point! Yes, the particular tool you learn will become obsolete, but debugging between Eclipse, gdb, Visual Studio etc. is all basically the same. The knowledge you get is transferrable, just like they have a head start if you teach them C++ and they end up in a Java shop. Teach them tools tha…

> I really strongly encourage you to set up your students with IDEs. Have a few seminars on how to set up a Visual Studio environment, and how to debug a large codebase. You can find lots of information about that using a search engine of your choice. Any student should be able to use Google. So there's no reason to waste teaching ressources for that purpose.

That is a bit weird thing to say. Lots and lots of things can be found using a search engine, but it doesn't mean they shouldn't be taught.

Re: Why Don't Schools Teach Debugging?

#127

Post by Illotus »

wolfgke wrote: post #124
analog31 wrote: post #65

Earlier quoted context omitted.

Thanks for the comment. I agree that tools go obsolete quickly. But it occurs to me that debugging is both a set of tools but also a knack. I'm curious what you think about how to teach the knack.

How to teach the knack: Write lots of code that uses the most sketchy language features available. The chance is high that soon you'll get code that doesn't work. Now go through each line (source code or assembly) using a debugger of your choice and get it to work again. Do this until there is nothing that will scare you anymore.

Also, do lots of maintenance programming. Finding bugs in code someone else wrote is generally much more difficult (and in my opinion valuable in learning sense), because you aren't familiar with it.

Re: Why Don't Schools Teach Debugging?

#128

Post by fredophile »

blah32497 wrote: post #106
jarvic wrote: post #51

Earlier quoted context omitted.

>They don't want to teach any "tools" b/c CS professors find teaching people how to be good developers as beneath them. They honest to god think CS is an actually hard science on par with math and physics. Despite what you (and a lot developers that I've talked to) seem to think, CS is a hard science. However, CS and software development are not the same thing. Most CS programs are taught by professors who have resea…

"CS is a hard science" Hahaha. As someone who did a degree in physics, computer "science" is a joke when it comes to math. They took one of the easiest field of mathematics and rolled it in to a half-assed degree. Sure you learn some logic and some graph theory (yeah, lets try to avoid numbers as much as possible...) but it's not at a very high level. I seriously doubt CS professors are making significant contributio…

Why do you say CS takes one of the easiest fields in mathematics? People have been studying CS since long before we had computers and there are still famous open problems. If the math is so easy perhaps you'd like to give a proof for P=NP (or P!=NP) and claim your million dollars? Do you really think CS is all discrete math and graph theory? I don't go around claiming physics is easy because Newtonian mechanics are simple. I'd also argue that math only gets interesting once you take the numbers away. If all you're doing is number crunching you should probably just write some code instead. Computers are good at that sort of thing.

In my experience the real disconnect with CS degrees is expectations about what is and what should be taught. A lot of students want a vocational program. Universities end up teaching a hodgepodge of topics such as how to write code in a particular language, program design/software engineering, algorithms and complexity, discipline specific specialties (e.g. AI, OSes), computability, etc.

When I was in university I was taught how to debug my code with ddd and gdb. Was this a waste of my time because I no longer use them? Of course not. Everything I learned with them carries over to the debuggers I use everyday. My degree also covered several languages that I've never used outside of classes. The skills I learned learning them help me any time I want to pick up a new language and start coding.

Code is not a primary tool for expressing algorithms and concepts. Code is how I tell the computer what to do. If code was so good for communicating concepts and algorithms to other people I wouldn't need to write comments. I also haven't seen any algorithm books that include real code. The closest you'll get there is MIX. Good luck programming a real application in that.

Re: Why Don't Schools Teach Debugging?

#129

Post by fredophile »

MichaelMoser123 wrote: post #123
mandor wrote: post #61

Earlier quoted context omitted.

CS prof. here. We don't want to teach "tools" (e.g. IDE) because they are always changing. There is no point is knowing how to set up an IDE when the IDE will have a different GUI before the student graduates. We teach"unix tools" a bit more because they did not change much during the last decades. My goal is to teach "concepts" (which is hard) and use tools as examples of these concepts. Dealing with the specifics o…

For really big programs you can't use valgrind; valgrind causes significant performance hit and the system often starts to choke under the the memory load. Also GDB really alters the timing of things, so it is bad at timing/multithreading bugs. Mostly what helps is working through the logs & traces / following through the code along as you pass through the traces; Use a needle and a steady hand ;-) i guess that's wha…

Valgrind is fine for teaching students. I would probably use something faster and more sophisticated (and probably more expensive) in a professional setting but that doesn't mean there's nothing to learn from using it.

Adding logging also changes timing. Those aren't just NOPs you're throwing in. Also, changing timing isn't always a bad thing. Sometimes you can get a bug from a race condition to happen more often with the debugger.

Re: Why Don't Schools Teach Debugging?

#130

Post by blah32497 »

mkartic wrote: post #125
blah32497 wrote: post #106

Earlier quoted context omitted.

"CS is a hard science" Hahaha. As someone who did a degree in physics, computer "science" is a joke when it comes to math. They took one of the easiest field of mathematics and rolled it in to a half-assed degree. Sure you learn some logic and some graph theory (yeah, lets try to avoid numbers as much as possible...) but it's not at a very high level. I seriously doubt CS professors are making significant contributio…

Why the bitterness against CS? As jarvic says, > However, CS and software development are not the same thing. A lot of schools offer a separate degree in Software engineering as opposed to CS (or at least separate tracks). So the distinction is pretty clear. Where I studied, there are separate degrees for CS and IT. You seem to be fudging the two. Do you expect physics majors to be mechanical engineers automatically?…

Sorry if I came off as bitter. I'm a couple of years out of college and honest I felt that the CS department was pretty self entitled and misguided.

"CS degrees teach you algorithms"

Yeah it does. And it doesn't feel like it's really enough. There isn't a feeling by the end that you've learned only a small fraction of the algorithms and I guess it felt like there wasn't all that much science.

I went to a school with a decent department (I think top 20 in the US) but I never felt like they were actually doing any real, interesting, groundbreaking research.

In contrast, the Physics department is doing all sorts of stuff. Quantum computing, CERN related stuff, building new astronomical sensors, string theory stuff etc. etc. They've got their own problems, but at least it's something you can point to.

Physics majors are sorta screwed. Physics is sorta the opposite of CS. When you're done you feel like you've only learned a tiny bit and that there is so much more to understand. If you're not trying to go to grad school, the department doesn't really care about you. You end up having no marketable skills and your selling point is "I-went-through-a-insanely-difficult-degree-and-i'm-good-at-problem-solving". Most people can sorta code in Python, and sorta can do some circuit stuff. It's pretty bad.

People end up teaching, or working in unrelated jobs. Or going to grad school in related disciplines. One of my buddies ended up picking grapes with illegal immigrants.

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