Computer Science from the Bottom Up (2016)
31–40 of 79 posts
Re: Computer Science from the Bottom Up (2016)
#32Author here ... Yes as pointed out many times not "computer science" and I somewhat regret the name. However, it came out of me being a teaching assistant for people doing computer science degrees. A surprising number of people got to 3rd year operating systems courses without realising things like 2^10 is a kilobyte, 2^20 is a megabyte, etc. Let alone how a program was linked and loaded. I hope for this to be helpfu…
Hello, thanks for releasing this! Are there any plans to release chapter 10?
It is written in DocBook, which has become increasingly annoying to publish with and I think is, unfortunately, unmaintained now.
I have been considering some parts on containers and virtualisation which isn't covered at all.
The Itanium and PowerPC examples probably haven't aged well. There is no question that Itanium is a very interesting architecture with many interesting features, but now it is dead it's like deciphering hieroglyphs. I think I have to update these to ARM, or maybe even RISC-V to be more relevant moving forward.
So that would be my plans, as they were :)
Re: Computer Science from the Bottom Up (2016)
#33Author here ... Yes as pointed out many times not "computer science" and I somewhat regret the name. However, it came out of me being a teaching assistant for people doing computer science degrees. A surprising number of people got to 3rd year operating systems courses without realising things like 2^10 is a kilobyte, 2^20 is a megabyte, etc. Let alone how a program was linked and loaded. I hope for this to be helpfu…
I actually think "bottom up" is more of a misnomer than "computer science" as a title for this material, since when I think of "bottom up" I think of things like nand2tetris and Petzold's book. This looks more like "selected topics in operating systems" with some review of computer architecture basics mixed in.
Re: Computer Science from the Bottom Up (2016)
#34Author here ... Yes as pointed out many times not "computer science" and I somewhat regret the name. However, it came out of me being a teaching assistant for people doing computer science degrees. A surprising number of people got to 3rd year operating systems courses without realising things like 2^10 is a kilobyte, 2^20 is a megabyte, etc. Let alone how a program was linked and loaded. I hope for this to be helpfu…
I actually think "bottom up" is more of a misnomer than "computer science" as a title for this material, since when I think of "bottom up" I think of things like nand2tetris and Petzold's book. This looks more like "selected topics in operating systems" with some review of computer architecture basics mixed in.
This was really seeded for me when trying to teach people taking computer science courses who were trying to do practical things like integrate C libraries into their higher level projects, but didn't really understand how things were working under the hood and getting themselves into a mess.
If they understood a little more about how their program was built and run ... from the bottom up, as it were :) ... they would have had less pain.
Of course, it just shows as usual the hardest problem in computer science is indeed, naming!
Edit: BTW you're right, "Code" by Petzold should be required reading http://www.charlespetzold.com/code/index.html
Re: Computer Science from the Bottom Up (2016)
#35Earlier quoted context omitted.
Isn't it amazing how people pass courses, even perhaps demonstrate mastery at a point in time, but manage to get to later courses without fully understanding things? Students end up with a very strange mental framework by the time they graduate, and it seems like most students actually know shockingly little. I don't know that there's a solution, or even that it's an issue. To me, this is simply a reflection of how p…
When I did my CS programme decades ago, we all started with Scheme, which is very high-level, and forced everyone to focus on the algorithms, the math of it, instead of what the hardware is doing, or how the Scheme interpreter is implemented. It gets you going, thinking about values and execution and iteration and recursion. Starting with bits and bytes and hardware would be pretty goddamn boring, I think. You'd lose…
I think it depends on the audience.
For a group of prospective CS majors, or people learning programming for its own sake, I think it would be good to start with a high level language, say Python, Scheme or Ocaml, and then progressively deconstruct the layers of abstraction between the language and the physics.
For a group of electrical engineering majors, it might actually tie in better with their other courses if one starts with simple physical constructs like bits, bytes, and gates, and gradually introduce abstraction layers to form more convenient programming models.
Re: Computer Science from the Bottom Up (2016)
#36Author here ... Yes as pointed out many times not "computer science" and I somewhat regret the name. However, it came out of me being a teaching assistant for people doing computer science degrees. A surprising number of people got to 3rd year operating systems courses without realising things like 2^10 is a kilobyte, 2^20 is a megabyte, etc. Let alone how a program was linked and loaded. I hope for this to be helpfu…
Hey, so this is a great work you did. One thing perhaps you can explain... I've stared at this example now for like 30 minutes...
https://www.bottomupcs.com/chapter01.xhtml
Section on "Masking"
How do you get 0x09 or 0x90?
I get how using & = ...
so:
10100101
&
11110000
=
10100000
But I have yet to see how this is 0x90 or 0x09, perhaps I'm misunderstanding. I'm trying to understand the 'shift' piece of it
Re: Computer Science from the Bottom Up (2016)
#37Author here ... Yes as pointed out many times not "computer science" and I somewhat regret the name. However, it came out of me being a teaching assistant for people doing computer science degrees. A surprising number of people got to 3rd year operating systems courses without realising things like 2^10 is a kilobyte, 2^20 is a megabyte, etc. Let alone how a program was linked and loaded. I hope for this to be helpfu…
Hey, so this is a great work you did. One thing perhaps you can explain... I've stared at this example now for like 30 minutes... https://www.bottomupcs.com/chapter01.xhtml Section on "Masking" How do you get 0x09 or 0x90? I get how using & = ... so: 10100101 & 11110000 = 10100000 But I have yet to see how this is 0x90 or 0x09, perhaps I'm misunderstanding. I'm trying to understand the 'shift' piece of it
It’s a typo: he meant 0xa0 or 0x0a and the shift is the four positions to the right to extract the top nybble of the byte.
Re: Computer Science from the Bottom Up (2016)
#38Author here ... Yes as pointed out many times not "computer science" and I somewhat regret the name. However, it came out of me being a teaching assistant for people doing computer science degrees. A surprising number of people got to 3rd year operating systems courses without realising things like 2^10 is a kilobyte, 2^20 is a megabyte, etc. Let alone how a program was linked and loaded. I hope for this to be helpfu…
Isn't it amazing how people pass courses, even perhaps demonstrate mastery at a point in time, but manage to get to later courses without fully understanding things? Students end up with a very strange mental framework by the time they graduate, and it seems like most students actually know shockingly little. I don't know that there's a solution, or even that it's an issue. To me, this is simply a reflection of how p…
> Isn't it amazing how people pass courses, even perhaps demonstrate mastery at a point in time, but manage to get to later courses without fully understanding things?
People remember what they are required to recall (citation needed). Classes can only test for so many things, so people are going to remember what they needed for assignments or tests. It feels like that's one of the reasons apprenticeships are hailed by some as useful. They "test" what is required in real world application. I've never needed to know that 2^10 is a kilobyte as a developer building websites, but would that be surprising/amazing? There are many things I've needed outside of school that were never taught.
As long as CS is used as the path to software development, it will be a balance between theory and application.
Re: Computer Science from the Bottom Up (2016)
#39Author here ... Yes as pointed out many times not "computer science" and I somewhat regret the name. However, it came out of me being a teaching assistant for people doing computer science degrees. A surprising number of people got to 3rd year operating systems courses without realising things like 2^10 is a kilobyte, 2^20 is a megabyte, etc. Let alone how a program was linked and loaded. I hope for this to be helpfu…
Isn't it amazing how people pass courses, even perhaps demonstrate mastery at a point in time, but manage to get to later courses without fully understanding things? Students end up with a very strange mental framework by the time they graduate, and it seems like most students actually know shockingly little. I don't know that there's a solution, or even that it's an issue. To me, this is simply a reflection of how p…
Most students approach courses as a form of top-down search with a cache for items they see often. It is generally difficult to get them to reason about subjects from the bottom up.
A smaller proportion of students approach courses from the bottom-up (10-20%?) - they tend to start with the basic pieces and glue them together over time to understand larger concepts.
I’ve read about this phenomenon (it is extensively documented in pedagogic literature) and seen it in action (I taught CS for about ten years) but still could not explain to you why that split occurs.
I would speculate that it is a difference in type-1 vs type-2 reasoning based on the level of familiarity and comfort with the prerequisites to each course, but even that guess is heavily biased by studying constructivism in CS pedagogy.
Re: Computer Science from the Bottom Up (2016)
#40I remember reading this a few years back.
I stopped reading at some point because there were so many errors, unfinished bits, and just flat-out garbage.
Sorry to the author but this needs to improve. It's a good start, but you need to invite fixes and implement them. Put your email address on every single page and invite fixes and then implement them.
This could be an awesome resource, but right now it's too full of errors to be useful.
Nobody should be recommending this. Nobody who had actually reviewed it all would recommend it.