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From the text:

We now have all the information to compute the optimal two egg solution.

While I prefer to read about algorithms and strategies in the fashion the author writes, I'm a bit sad that there's is no proof (or informal reasoning) why this is the optimal solution. Does anyone have a paper or some reasoning which will make me believe that this is the optimal solution?

JeanPierreon Shall We Use Clojure?

Anyway, having followed through their examples and done some of my own Clojure programming, I ended up not so convinced that people who are good at solving story-style imperative problems will necessarily be good at solving math-style functional problems. It felt like a different part of my brain.

When you're coming to a new paradigm which is completely different from what you're currently using, then of course it will initially feel hard/different and that you're using a different part of your brain. That doesn't necessarily mean that it's harder for you to program in a functional style, it just means that you're more experienced in imperative programming.

JeanPierreon 20 lines of code that beat A/B testing every time

How does a decay factor not "trust your 'new' data more than really 'old' data"?

JeanPierreon Quotes about programming languages

I think http://en.wikiquote.org/wiki/Programming_languages has a better list of programming language quotes. As this list, it contains a lot of ha-ha jokes, but at least it contains more of the "good" quotes too.

JeanPierreon Automatic programming: write code that writes code

Isn't that just syntactic sugar[1]? I cannot see any kind of metaprogramming going on here - unless you can define attr_accessor and similar parts yourself.

[1] http://en.wikipedia.org/wiki/Syntactic_sugar

JeanPierreon When the cops subpoena your Facebook information, here's what FB sends the cops

Ah, I see. So this falls into the category of "very hard to fabricate"-evidence, if I get you right. Then, that makes it reasonable to use it as evidence.

Just a though experiment: Would a mobile phone with these possibilities (sending messages with specific data at a specific time, or calling another phone of this type and transmit preproduced sound input, all without being able to distinguish between a "timed" message/call and a normal one) be a legal electronic device? If so, will they change how the law looks at evidence of this kind?

JeanPierreon When the cops subpoena your Facebook information, here's what FB sends the cops

I find evidence from mobile phones to be potentially problematic. If they track your position, you could just leave your mobile phone home when doing crimes, and say that you are home (You can tape it to your dog to make more realistic movement). If they track activity (but not content), you can make a program which sends empty messages to another mobile phone, or calls another mobile phone at some specific time. Finally, if you track content as well, create the content of the messages while you define when to send them, or make a predefined sound record which you transmit when the phone call is coming up.

You could be in a one hour phone call while the robbery you performed happened, and that phone call had your voice in it, and you were home while you called. Isn't that quite the alibi?

Hard? Sure thing. Impossible? Nope.

JeanPierreon Notch live coding 0x10c

Yeah, that's hotswap in practical use. When using debug mode in Eclipse, you're able hotswap - which basically means that you can change the content of a method while the program is running. When the method is called again, the new content will be executed.

JeanPierreon 60 minutes: Is sugar toxic?

As a person who read about studies like these, how do I filter out the "real" studies versus the studies blown out of proportions? I've read Ben Goldacre's Bad Science (which I highly recommend), but I don't have the time to do much research on every study newspapers/other media come out with. Is there a simple way to find out whether this - or any other study, for that matter - is a study to take seriously?

JeanPierreon Norwegian government tax portal security scandal

I really hope this change how our politicians view computer applications and electronic data. Last year, they decided to implement the data retention directive (http://en.wikipedia.org/wiki/Data_Retention_Directive), arguing that the odds of a security hole was close to zero due because "technology development" has removed those holes.

JeanPierreon I’m calling it: Ubuntu is finally ready for the world.

The main problem with the distros available today is their lack of non-free software. No matter how much you or I like free software, Minecraft can't run as good on OpenJDK as on Sun JDK, and I automatically install the proprietary Flash version because the other one's just way too laggy to use. I also always run smxi to get the best graphics drivers and compability with the least amount of work.

And even then I struggle with drivers: I went from a Radeon HD 6870 to a GTX 550 TI just to be able to run Linux on my machine. There is probably some way to install the HD 6870 on a linux machine, but after using 26 hours on that card trying to get it to work (I timed it), I gave up. Imagine if I used those 26 hours on work instead.

People don't care whether stuff is free or not: They just want stuff that works. If you can't get that without setting up non-free repositories and download proprietary graphic drivers for your graphics card, then you won't get normal people to use your operating system.

JeanPierreon The Evolution of a Python Programmer

As far as I know, 0! = 1, so I assume you meant non-negative integers instead of positive integers?

JeanPierreon Teal and Orange in Hollywood movies

The point he's making is that work, art and design done by the author doesn't have anything to do with the arguments he puts forward in the article/blogpost. If the arguments he uses are wrong, point that out and explain why they are wrong.

JeanPierreon Think Stats: Probability and Statistics for Programmers

If you've gone through this book and want to learn more ways to use statistics and probability, you should look at the videos from mathematicalmonk[1] on youtube - he's like Khan for Machine Learning and more rigorous probability. It helps learning Machine Learning and Hidden Markov Models pretty well, at least from my experience.

http://www.youtube.com/user/mathematicalmonk

JeanPierreon Games company claims their graphics are 100,000x better

What is somewhat disappointing is that they don't tell if they have managed to solve these issues or not, as they were clearly commented on one year ago. Another major issue is the RAM-usage, as point cloud data will require a lot of memory.

Their claims of being 100,000 times better than current technology is also "frustrating", as it is repeatedly mentioned as if you've for some strange reason forgot it in the last 30 seconds. It is also a lie if they cannot use this in a game: I would suspect it's not impossible to increase the level of polygons to 10-100 times the amount - if not even more - if there's no animations or dynamic light sources around.

JeanPierreon Free online version of Stanford's Fall 2011 Intro to AI course

Khan Academy has actually covered everything I've gone through in my statistics class and linear algebra classes, so I'll recommend that as I'm going two semesters with AIMA the upcoming year.

http://www.khanacademy.org/#linear-algebra

http://www.khanacademy.org/#probability

http://www.khanacademy.org/#statistics

JeanPierreon Norway’s Premier Vows to Keep an Open Society

It's hard to compare the events and the psychological impact, but keep in mind that most of the victims are children, came from all over the country and knew the PM and rest of the parliament, especially the Labour party.

As far as I know, September 11 was an attack that killed people who worked in office and affected people who lived in or near New York the most, and did not hurt Bush administration like the Oslo-attack did.

I would suspect that may make it worse to bear for the Norwegian people, but as stated, it's hard to compare.

JeanPierreon Wikipedia: Making of Doom

To elaborate on its usefullness: An XOR-swap is only useful when you do not have space for a new pointer, otherwise, making a new temporary variable will on most processors be faster than XOR-swapping.

JeanPierreon Nearly Half of All College Grades Are A's

In Norway, we have the opposite problem: Nearly half of the grades in some subjects at NTNU are Fs, and 40% of all students get an F every year. The institute for IT, maths and electronics implicitly says that "a high failure rate means the standard is high", and they ignore feedback and complaints about professors.

Luckily (if I should put it like that), the grades themselves are usually fair. It's just that some subjects require too much work to be considered as one subject, which seems to be the university's intentions.

JeanPierreon Dyslexie: A typeface for dyslexics

Interestingly, the much hated font Comic Sans is another good font for dyslexics because the letters look more different from each other than e.g. Times New Roman. Therefore, if you're making invitations to your son's 7-year old birthday, Comic Sans is a great font for the text.

JeanPierreon Automata via Macros (Lisp) [pdf]

As this is a DFA, I wonder if it is possible to create a NFA via macros. One way would obviously be to turn the NFA into the DFA at compile-time, and then apply the DFA-macro, but that may possibly kill efficiency. Is it possible to do without creating infinite loops because of ϵ-transitions, and with tail calls? I have my doubts, but that would be amazing.

JeanPierreon Paper.js — The Swiss Army Knife of Vector Graphics Scripting

I haven't used Paper.js, but I've used Raphaël and the main differences I see right now is that Paper uses Canvas, while Raphaël simulates/uses SVG. As a result, Paper should be more practical for making dynamic content that uses user input or is "very dynamic".

Raphaël on the other hand, provides a simple system for making relatively "static" vector images with very good support for a lot of browsers (IE6 support, even). If you need user input, I think I would've tested out Paper and most likely ended up with that.

So basically: Raphaël for vector images that may be scaled and simple, dynamic images. Paper for animations and e.g. games.

JeanPierreon 10000 things all CS students should do before graduating

(It seems like all the points in my list have been interpreted in many different ways here, so I apologize beforehand if any of you misinterpreted my list.)

I'm not talking about wasting years here, I'm talking about something that is possible to learn in a single course. [1] Also, I'm not talking about making a computer from scratch by building your own circuit board and make your completely own compiler to your newly designed programming language for your home made OS without any proper design. I meant simple stuff - simple compilers[2] and operative systems, because it may actually come back and help you someday - even if you're not going to make a programming language[3] or an operating system.

[1] http://video.google.com/videoplay?docid=7654043762021156507#

[2] http://norvig.com/lispy.html (maybe not THAT simple, but the idea is that doesn't have to take that long or be that hard.)

[3] http://steve-yegge.blogspot.com/2007/06/rich-programmer-food...

JeanPierreon 10000 things all CS students should do before graduating

It's an interesting list, but I do believe it lacks a lot of computer-specific things which I personally think people should do. For example

  - Build your own computer
  - Build your own (small) operative system
  - Build your own programming language

would be on my list of things a CS-student should do before graduating, because you will most likely get into problems where knowledge of the three things mentioned above will help you understand/solve the problem. Obviously, that list is not complete, but I think those are some of the more important points.

JeanPierreon How we got the unusual symbol used for the Mac menu command key

Same in Norway, and I assume this is how these signs are used throughout the Nordic countries. "Severdighet" could also be roughly translated into "tourist attractions", as they are mostly used for that.

http://i.imgur.com/0jdn2.jpg

JeanPierreon Picking holes in mathematics: Finitely stated, undecidable propositions

I'm curious: If you add a new axiom in order to make a undecidable proposition decidable, will this new axiom add more than one undecidable proposition, or is the number of new undecidable propositions unknown? Or are there infinitely undecidable propositions for every set of rules?

If the former is true, couldn't we theoretically just apply axioms in order to solve undecidable propositions which have a practical application if solved? Or will it practically be hard to find these axioms?

JeanPierreon Ask HN: Programming Problems for Plane Rides

You could always download earlier topcoder-contests (http://www.topcoder.com), specifically single round matches for algorithms. They have a time limit on 75 minutes for 3 exercises, and should keep you busy for roughly that amount of time.

JeanPierreon Why GNU grep is fast

I have to disagree, and I could actually use Boyer-Moore as an example on this:

Split the string you're searching into four roughly equal pieces, with an overlap so that potential matches is guaranteed to be found. Then do a Boyer-Moore on those in parallel. E.g. if you look after FOO, you'd have to split the string like this (pipes are the start/end of the piece exclusive, i.e. piece 1 does not contain the last O)

    piece 1 here|
  ...7890abcdeFOOghijk
             |piece 2 here

Now, what we know is that in the worst cases, this would require more operations: The O may be detected by piece 1, and it will check if the character in front is an O as well. Piece 2 will also check the same O, so there's redundant computation going on. However, this is theoretically faster (I'd guess it is practically faster for large files) even though this requires more operations.

JeanPierreon What life lessons are unintuitive or go against common sense or wisdom?

Happiness = Outcome - Expectations. The key to enjoying life is keeping expectations low to the degree that you're always pleasantly surprised.

I find this a bad advice due to many different reasons. First and foremost, startups must have high expectations in order to, well, start up. People would never, ever create a company assuming it would go straight to hell after six months.

What also bothers me with this statement is that, by keeping expectations low, you would probably not work as much as you would if you had higher expectations.

As a final note, I have always kept my expectations very, very high. I always aim for A's at university. Yet, I do not feel less happy than the average Joe, even though I sometimes get a B or a C.