That's like saying a well-written C program is a good reference for C++. In any case, writing POSIX-only shell scripts is much harder than writing Bash scripts, which can often be much faster (e.g., one can use {1..10}, which doesn't need an external call, instead of `seq 1 10` to iterate through a list of numbers). For POSIX-only shell scripts, the ones used in Git [1] are some of the best-written I've seen.
Not being pedantic, but OP's script isn't Bash, it's POSIX sh. POSIX sh can be executed in Bash, but there are several differences. The only non-POSIX command I can spot in that script is shuf.
> Why in the fuck do I have to pay a publisher to submit homework to my professor?
The argument is that it makes it easier for the professors/teachers to grade homework when they're submitted electronically. Of course, that's a stupid argument since part of a professor's job is teaching students, and that inevitably involves grading things. Few professors would be convinced by such an argument though.
Indeed, I would say most "modern" introductory physics textbooks (including newer editions of old texts like Halliday and Resnick or Sears and Zemansky) are terrible. Of course, the quality of printing, graphics, etc. have improved, but I don't think students ought to pay $300 for just that.
This is an excellent article. Much of the discussion about digital vs. dead-tree books is similar to Stallman's "Right to Read" essay [1], which was published 22 years ago in 1997. As a graduate teaching assistant who has taught several introductory physics courses in an American university, I've noticed that book publishers like Pearson and MacMillan have been pushing students to buy/subscribe digital versions of their textbooks. Professors also increasingly assign homeworks online rather than make students do it on paper. This is really sad because it's really difficult to learn physics without actually doing pen-and-paper calculations. As an example, in a particular homework on vector addition, students were asked to draw the resultant vectors on some poorly-written JS based web notebook, and the students spent more time getting the thing to work instead of learning vector addition.
I can also understand why publishers push for digital subscriptions. Introductory physics textbooks have hardly changed in the past 30-40 years (I would even say they were less distracting and had better problems 30 years ago than now), and it should be obvious for the execs at Pearson and MacMillan that their business model is not going to survive unless they introduce subscription based textbooks. You really don't need anything more than an old (SI-units based) copy of Halliday & Resnick to learn introductory physics.
Not that I know of, but many of the problems have been discussed online, e.g, calculating the average of the 100th power of sin in under 5 minutes [1], which according to Arnold, if you cannot solve, you don't understand mathematics.
1. "What Is Mathematics? An Elementary Approach to Ideas and Methods" by Courant and Robbins -- a general book on mathematics in the spirit of Feynman lectures.
2. Strogatz's "Nonlinear Dynamics and Chaos" -- it's a bit narrow in scope (mostly dynamical systems with a little bit of chaos/fractals thrown in) but very good nonetheless.
4. Cornelius Lanczos, "The Variational Principles of Mechanics" -- this is a physics book, but one of the classics in the subject, and as Gerald Sussman once remarked, you glean new insights each time you read it.
5. Cornelius Lanczos, "Linear Differential Operators" -- an excellent treatment of differential operators, Green's functions, and other things that one encounters in infinite-dimensional vector spaces. This book has some very intuitive explanations, e.g., why d/dx is not self-adjoint (i.e., Hermitian), whereas d^2/dx^2 is.
For chemistry, I would recommend "General Chemistry" by Linus Pauling, even though it's a bit outdated.
This is nuts. Mozilla should at least allow the user to set a custom search engine using an about:config option, like the old keyword.URL [1] option, which was removed after Firefox 23. I use DuckDuckGo with several customizations as POST parameters and it would be very cumbersome if I have to write an extension to use DDG the way I want it.
> I also loved Louisa Gilder’s The Age of Entanglement and Kip Thorne’s Black Holes and Time Warps. That one was slow for me, but it was like being in the kind of physics class I always dreamed of taking. At Harvard I had taken a class, Physics for Poets. The professor said in an impatient way, “If you can’t follow the math, then you don’t have to, but I can’t really explain it without the math, so just do the best you can.”
And this is true. You can't learn physics by listening to a physicist talk or by reading popular science books. The title of the article gave me the impression that the author picked up a university-level book in physics and worked through it. As far as reading popular science goes, I think a lot of SF authors do that. And there are also SF authors who dig deeply into the science they write about (e.g., Greg Egan, Peter Watts, etc.).
In Kim Stanley Robinson's 2312, Venus is terraformed by inserting a large sunshade in the L1 Lagrange point of the Venus-Sun system. This makes Venus significantly cooler and atmospheric CO2 freezes. The frozen CO2 is then easily removed.
> I can see definitely a lot of added value to the scientific document there.
You fail to see that nonprofit publishers (IEEE, AIP, APS, AMS, etc.) also typeset and copyedit articles just like Elsevier, and that too at a much smaller price. The point is that you don't have to charge customers exorbitantly if the only thing they are gaining on publishing with Elsevier is neatly typeset articles. Further, Elsevier outsources the production of its papers to companies [1] in India. If it's production quality that one wants, those companies can probably do it at a fiftieth of the price Elsevier finally charges the customer.
Even if they don't read HN, I'm sure Elsevier execs know about the general discontent against costly journals. There have been numerous campaigns [1] to boycott journals published by Elsevier.