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https://github.com/mmaldacker/Vortex2D

It should work on macOS/iOS via MoltenVK, but I haven't tested it extensively.

It's a hybrid simulation with particles for the advection and a grid to ensure incompressibility.


1. The "reverse-complement" problem here is simply about reading a file, reversing strings and mapping a small set of characters to another one and printing the result. This is really a simple problem and there aren't a lot of optimisations to be done. Really this about having the fastest I/O library and thus doesn't seem like a good way to compare C and Haskell. If you look at the various solutions presented on benchmark games, the core algorithms are all the same and they only differ on how to read/write and the use of threads.

2. The author talks about the importance of reducing cache misses due to pointer indirection and then proceeds by implementing a character buffer as a linked list of small buffers...

3. The C version reads and writes character one by one, this can be greatly improved by reading/writing bigger chunks at once. Actually, the author points out this optimisation but says "that would require significant changes to the code;". So the author spent time optimising the Haskell version, but spending time optimising the C version is too much work? And then arrives at the conclusion Haskell is faster?

4. Commenters on the author's blog cannot reproduce the results...


This falls in the very specialized fields, but traders/brokers certainly need to be good at mental calculations.


> the Netherlands has fewer than 17 million residents and a language that nobody else speaks

If you don't count the flemish in Belgium (about 6-7 million people). In addition, (almost) everybody speaks english.

> One of the hardships Dutch startups face, says Kroes, is overcoming the natural Dutch tendency to be humble.

Really? This is not the impression I get from the Dutch. Belgians love to make fun of Dutch people for being arrogant. There is also a very strong culture of entrepreneurship in the Netherlands, starting and having a successful company is highly regarded. And there are already a few successful startups, like ticketswap which recently opened in several other countries.


Technological advancements are made. UDP Broadcast was completely broken in the 90s in Linux and was fixed by people in the finance industry. High speed network cards are constantly improving thanks to those same people.


dictionary is not necessary, the C++ impl just counts the number of words. This can be written as:

  int word_count(const char *const filename)
  {
    std::ifstream file{filename};
    return std::distance(std::istream_iterator<std::string>{file}, {}); 
  }


>Back in the 70s, you could rock up at the airport twenty minutes before your flight left

This still exists, for example Tegel airport in Berlin. Also, in the 70s there was waaaaaay less traffic in airports so it is simply not a fair comparison.

>Sadly, I bet the way we'll end up equalizing this will be that somebody will eventually bomb a TGV and we'll have to start doing the two hour confiscate-your-kids'-apple-juice routine at the train station too.

http://en.wikipedia.org/wiki/2004_Madrid_train_bombings

http://en.wikipedia.org/wiki/7_July_2005_London_bombings


Internal flights in Japan are basically turn-up-and-go (and cheap too), and have only a little security.


So that's fascinating. Having no expertise whatsoever on the topic of domestic Japanese transportation my immediate response is "Strong competition from fast rail means that air travel is a superior experience"

It breaks my heart we don't have fast rail in the US. Even if it was just the North Eastern corridor (extended maybe to Chicago and Atlanta) it would have a huge impact on air travel. Of course the cost and final date to roll this out means it's probably not worth buying into.


Texas has a project of a high speed train between Houston and Dallas, it would link the 2 cities in 90mn (instead of 3:30h of driving, or 70mn of plane. So if you spend more 20mn more at the airport than at the rail station , the train would be faster. http://texascentral.com/the-facts/

http://www.houstonchronicle.com/local/gray-matters/article/T...

It's a privately own project, supposedly ready in 2021.


you can even bring your own bottled drinks/liquid on Japan domestic flights. they have a machine specifically for "scanning" drink/liquid. put your bottle on it, green light, then off you go. not sure how it works


Something like:

    num_checks += 1                                                                                                                                                                                         
    if num_checks % 200000 == 0:                                                                                                                                                                            
        red_light()                                                                                                                                                                                         
    else:                                                                                                                                                                                                   
        green_light()


There's a UK company in talks with the DoD on rolling these out for military use, and I'm sure they will expand to civilian airports eventually. I'm not sure if this is the same company, but they're doing the same thing: http://www.theguardian.com/business/2014/nov/02/scanner-anal...


Almost certainly a spectral analyzer. Shine a light through it, see what the chemical signature is.


That certainly won't work for my aluminum water bottle. Granted, neither do X-rays, and yet I've never had it even questioned going through security.


Yes, I was assuming a typical disposable transparent plastic or glass bottle. I have not seen the machine in question, so I am guessing, but it would be very easy to implement and cover the majority of cases.


I think we're assuming here that this machine isn't merely security theatre.


I wasn't even asked to show my ID the last time I flew domestically in Japan.


Tegel is fairly unique because each gate has its own security checkpoint. It's definitely a bit less stressful.


I found it more stressful. The biggest place where delays are caused at an airport is at security, so when I arrive at an airport, this is the first thing I want to take care of, and cannot relax until I've passed through it.

To be told I cannot go through security until a few moments before the flight departs (because it is not even open, or the gate not even assigned) means that anything that does go wrong will cause me to miss my flight.

Not to mention the expense of having screening apparatus at every gate seems a little inefficient. It means everyone on the flight tries to cram through the one line at the same time, whereas if it were in advance, it could be spread out in time and over more lines.


Amsterdam Schiphol is like this, too, and yeah, it's great. I think for them it's because they're going for this combination airport/mall/mini-city vibe, and there are enough amenities that they want it to be attractive as a destination, even for people not flying, so they want to keep as much of the airport outside of security as possible.


>and also remember Berlin's system is essentially new and was rebuilt after reunification so you are looking at a modern system.

After the reunification, they only had to reconnect the lines that were separated by the wall. Only a few places needed some extensive work. You probably meant WW2 where most lines were destroyed. Note that Berlin was also one of the first cities in the world to have a metro system.

>No one is keeping you from remaining in Germany, are they? I can guarantee you they will approve your work permit and you can become a resident and eventual citizen.

The horror!


No, they didn't simply have to connect some disconnected lines. Not only did the eastern infrastructure, have to largely be rebuilt from the ground up, but even the western part was outdated and old and reunification meant that billions were spent on upgrading infrastructure.


Upgrading and maintaining a transport infrastructure is necessary for big cities regardless of the wall circumstances. You don't think London, Paris and other big metropolitan cities in Europe spend billions on upgrading and maintaining their public transport infrastructure? I don't see Berlin having a completely automated metro like the DLR in London, or NFC cards like pretty much any other metro in Europe.


Berlin had a maglev metro for a short while back in 1989: http://en.wikipedia.org/wiki/M-Bahn


The barcelona chair is a classic furniture from the bauhaus period designed in 1929, which is not even close to the "midcentury" period defined in the article.


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