Ask HN: Why is Tesla worth $420B? - <AUTHOR> Stock is trading at all time highs but it's delivery numbers seem to be roughly the same over the last 6-8 quarters or so.
It's now more valuable than Johnson & Johnson and Visa.
What's going on here? <comment><USER2> Because capital is free right now just not to people and companies who don't already have a lot of it. Fed is spraying cash all over the country clubs and gated communities. Where are they going to put it? Highly visible stocks of large companies.

<comment><USER3> > Fed is spraying cash all over the country clubs and gated communities

Can you please elaborate on this? How exactly is this happening? Why specifically country clubs and gated communities?

<comment><USER4> He doesn't literally mean country clubs. He is saying that the fed's current policies allow rich corporations (controlled by rich people) to get loans at very low interest rates.

</comment></comment></comment><comment><USER5> Investors look for a stock that will appreciate in value. Not all investors look at actual sales or revenue figures (obviously). It's called the Greater Fool theory. It's smart to buy something overpriced if you can resell it to an even greater fool at a profit.

</comment><comment><USER6> I really think China has a lot to do with it. If Tesla is going to sell a lot of EVs anywhere, it's going to be China (and by a lot I mean the only conceivable market pushing for electric that could possibly justify that market cap).

The bet is they can sell about 4 million cars in China, I think. That can justify the 200 billionish projection.

Toyota sold something like 10 million cars globally in 2019. If Tesla really is the best electric car people want, it should just be a matter of ramping up production.

Edit: My numbers were all based on 200 billion valuation mistakenly, so just double everything.

<comment><USER7> I doubt at this point China wants to buy anything american. Plus Tesla does not have a good history of production neither quality.

</comment></comment><comment><USER8> Its worth more that gm, ford, Chrysler, and toyota combined. I am not sure what year they will make more cars, revenue, and profit than all those companies combined.

<comment><USER9> It's actually going to soon be worth more than all the major automakers on planet Earth combined. At the rate it's going, it'll hit that mark within a month or two.

That includes: VW, Porsche, GM, Ford, Daimler, BMW, Toyota, Fiat Chrysler, Honda, Hyundai, Nissan Renault, PSA, Suzuki. Combined.

Regardless of however long the ongoing stock market mania lasts, it's obviously going to obliterate a large number of shareholders on the way back down. There is no scenario where Tesla can fill in even a modest amount of that market cap.

Toyota is their absolute most extreme best case scenario. Toyota is worth less than 1/2 what Tesla is today. It would take decades for Tesla to get as large and profitable as Toyota if everything works out perfectly.

<comment><USER10> I believe the reason for the extra valuation of tesla is factoring in the potential of self driving cars and the market they can capture currently held by uber/lift - also the energy storage market and the solar market...

So while they sell cars and that is the majority of what they are known for now... it's believed in the future they will be worth more because of the AI and storage businesses

<comment><USER7> i think the main reason, as a follow up of your opinion is that Tesla is a technology company first and automaker second. This gives a huge potential to sell services that are unique/very specific that are tremendously expensive. Im talking about Cells/Battery technology, AI, Autonomous driving, Infotainment devices, Internet of things, Chargers etc... etc...

I think at this point the only Automaker that can follow up Tesla could be Toyota or VW.

</comment></comment></comment></comment><comment><USER11> Essentially because investors are desperate for growth and Tesla is one of the few non-social media / cloud companies that promise massive growth potential. This is largely driven by Musk, in the same way as Jobs was able to drive Apple. Tesla have a long way to go if they make the right moves.

</comment><comment><USER12> Because a sufficient number of people say it. That's pretty much the way most things in a free economy are valued.

</comment><comment><USER13> Because lots of retail investors (average people like you and me) from Robinhood app are willing to buy stocks. Good marketing and branding around Elon Musk.

With 420B market cap Tesla is worth more than Walmart who had 14B profit last year (half of whole Tesla 2019 revenue) and 500B revenue (20x of Tesla revenue)

</comment><comment><USER14> High speculative demand and low security availability. Similar to why bitcoin is worth 12k a coin.

</comment><comment><USER15> It's a bubble.

</comment><comment><USER16> It's the apple of cars.

<comment><USER8> Apple generates like 60 billion in cash. That is 3x revenue of tesla.

</comment></comment><comment><USER17> r/wallstreetbets is a good place to investigate this.

</comment><comment><USER18> Lots of people are speculating on direction of securities.

It has nothing to do with true or real value of underlying company

</comment><comment><USER19> Use your imagination my friend. And throw weak dollar and low rate on top of that.

</comment><comment> doopy-loopy2 People believe the company will be worth more in the future.

<comment><USER18> People beleive more people will buy the same thing they bought after they bought it

<comment><USER20> People believe "YOLO"

</comment></comment></comment><comment><USER21> Saudi money

</comment><comment><USER22> As a fundamental analysis investor, I find it so silly, it isn't even worth 1/10 of it. But those kind of movements happen every once in a while and I've learned to live with it and just observe.

The reason that it's happening?

So, one part of it is government driven: 0% rates, FREE MONEY, money printing press goes BRRRRRRRRRRRRRR.

Now for Tesla, it's the kids. The same that popped up cryptos through the roof in 2016-7.

Nowadays they are at r/wallstreetbets using robin hood.

Institutional investors are enjoying the ride as well.

People aren't also questioning FAANG and MSFT huge market caps without the same growth in the bottom line. Sure,, those companies are doing well, but they valuation rose much higher than they are able to give returns to its investors.

It's the same problem. I have 0 positions on those stocks because they are like cocaine for the mind and this will all eventually crash. Gold and real things are your best bet.

If it doesn't crash now, it means that there'll be a huge debasing of the dollar to match those valuations. There's just too much money in the economy and very little being produced.

I believe what we may see is that the dolar vs other currency pairs will devaluate a lot, meanwhile inflation will remain low for a little while and then it will hit everybody very hard, because it means for every imported good Americans will need to pay much more.

FED has a huge issue that it can't hike up interest rates or start cleaning up his huge balance and when inflation comes for real(not the 2% they expect, but more like Argentina style inflation), they won't be able to lower that inflation without literally stopping the economy.

It's as if QEs are hiding dust under the carpet to make the house look clean. Initially, it indeed looks clean and there's no impact. Even after a while it is still fine. But now there's like a mount everest of dust and the carpet can't hold it any longer. Once shit hits the fan, all americans(and western people) will feel it.

Americans like to believe in the fallacy of the reserve currency. Currency is currency. Every single currency can end up having huge inflation and turning to dust if enough money is printed. US has been able to get around having this problem because so many countries are dependent on it, but there's a limit and the writing is on the wall that this limit has been already reached. And when countries stop relying on US Dollars as it suffers too much debasing and can't be reliably used for trade anymore, the country we know as USA will just implode, because it's only real product it exports is the Dollar, which will be worthless.

World Economy will shift to China and Asian countries which produce most of the shit western economics consume and we'll have a new world order. It's about time.

<comment><USER3> Since the FED lowered interest rates to zero and started buying corporate bonds [0], I predicated dollar inflation would rise. How should someone like me (a blue collar working lower class) prepare for the storm? Should I invest in stocks? Buy property? Buy things like cars? How should I prepare for what's about to come?

It might seem speculative, but OP's comment is based on how economics works, so the storm is about to hit. The big question is when? And how should we prepare?

[0] [https://www.cnbc.com/2020/06/29/the-fed-is-buying-some-of- th...](https://www.cnbc.com/2020/06/29/the-fed-is-buying-some-of-the-biggest- companies-bonds-raising-questions-over-why.html)</comment></comment>


Ask HN: What are some quick to monetize ideas? - <AUTHOR> Looking for ideas that can quickly monetize. <comment><USER2> Sell something people want, if it's good, the money will come. Effort is the key, money is not easy, luck will play a part

</comment><comment><USER3> Sell something you don't want which has value to someone else. (eg. gold coins)</comment>


5 essential skills every web developer should have - <AUTHOR> https://usersnap.com/blog/skills-web-developer/ <comment><USER2> I disagree with the second point.</comment>


Ask HN: Women of HN, tell us about yourself and your journey in tech so far? - <AUTHOR> 	I almost never come across women on HN in the comments section or anywhere else. I am interested in knowing about women in tech and their journey, stories and challenges.<p>Feel free to share anything you like. <comment><USER2> Is this thread like Stephen Hawkings party for time travellers? :)

Serious question though, how do you know when you come across women in the HN comments?

<comment><USER3> you don't, but when unspecified with "as a woman.." I'm guessing people in the tech community are generally just assumed to be men since that's the majority

<comment><USER4> As a woman...

we have a secret: a lot of us also choose to "hide" behind gender-neutral usernames. It's a thing that makes life easier on the internet.

<comment><AUTHOR> I agree! Although I have my real first name in my user name, no one will know if I am a women as this is an Indian name and most of the world doesn't know if it's a male or a female name.

</comment></comment></comment></comment><comment><USER5> There's a game called Valhalla, in which there is a fictional version of the internet where everyone online is assumed to be female and where women didn't have to hide their gender in online communities to avoid biases. The game's take on internet culture feels absurdist, but the satire really hits home when you see threads like this that highlights how invisible women are in our IRL internet culture.

In an ideal world, women don't have to call out their gender in comments (as another user suggests). Instead, we shouldn't assume all posters are male by default.

<comment><USER6> I always find myself assuming the person writing the comment I'm reading to be a middle-aged white male, and I feel dumb and ashamed when I realize that's not it. FWIW I'm a white male living in a western country so I'm deeply privileged/prejudiced. It's good to have my biases put in check, but I wished I didn't have them in the first place.

Edit: typo it didn't->I didn't

<comment><USER7> > I'm a white male living in a western country so I'm deeply > privileged/prejudiced.

so is everyone else anywhere in the world. I've lived in India and Brazil.

> I wished it didn't have them in the first place.

How is this even possible :|. insn't our brain a pattern matching machine.</comment></comment></comment>


The Nazi and the Psychiatrist - <AUTHOR> http://www.scientificamerican.com/article.cfm?id=the-nazi-and-the-psychiatrist&print=true

<comment><USER2> _Kelley further noted that the prisoner was "cynical and filled with a mystic fatalism," which explained why he would not take responsibility for such wartime conduct as his murder of political opponents and complicity in genocide._

I doubt that commanders on the Allied side had any feelings of guilt about slaughtering German or Japanese civilians. They may not have been motivated by racism in particular, but their actions still killed many innocent people, needlessly.</comment>


Number of the Week: Billions in Gift Cards Go Unspent - <AUTHOR> http://blogs.wsj.com/economics/2011/12/24/number-of-the-week-billions-in-gift-cards-go-unspent/

<comment><USER2> It amazes me that gift cards are _ever_ purchased by anyone. The only possible benefit is to the vendor, in _every_ scenario, and this should be obvious:

\- If you spend less than the card amount and don't use the rest, the vendor wins.

\- If you spend more than the card amount, the vendor wins.

\- If you somehow spend the exact amount on the card, the vendor still wins because they made you buy something at _their_ store instead of a competitor's. Also, the card amount influenced the decision of what to buy, which wouldn't have happened when using cash.

It is also not only an unimaginative gift but a _bad_ gift, because:

\- You are compelling the recipient to shop at a particular store (a store that may not have what he or she really wants).

\- You are _probably_ compelling him or her to spend money that wouldn't have been spent otherwise, because the card may not cover everything (in this way, it's like a tax). And if more money isn't spent, the "gift" is worth even less than it was supposed to be.

\- You are stating pretty clearly what you think the person is worth. If I receive something nice, I might not think "this is worth $5", but when I am given a gift card I feel "oh, they think I'm only worth spending $5 on".

It would be nice if people would just identify gift cards as a massive scam and start giving real gifts again (or at least get over the apparent stigma carried with gifts of cash).</comment>


Confessions of a Book Pirate (2010) - <AUTHOR> https://themillions.com/2010/01/confessions-of-a-book-pirate.html <comment><USER2> I've been very poor (more than once), and I'm currently quite comfortable. I've always read a lot, and would be in a very different place if I hadn't. Using libraries has been a big part of that, but they are of course much less useful for cutting-edge tech topics. I'm limiting this to those, in situations where you think absorbing the book will improve your chops.

You should buy the book, because this makes both you and the author better off.

But if you can't, you should read it anyway, because at least one of you is benefiting. You can buy the book later when you're in a better place, or at least pay it forward in some other way.

The only thing worse than not getting paid for your work is your unpaid work not being used at all.

<comment><USER3> I bought the book (used), but I can't find it right now, so I borrowed it from the library, and this article just prompted me to do an online search for it, and I just downloaded a pdf copy.

</comment></comment><comment><USER4> It's a major embarrassment for humanity that we've created an astonishing library system – books in scanned or native digital format, inexpensive smartphones/e-reader devices, and the internet – that could give billions of people on the planet the ability to read nearly any book ever published essentially for free, but for narrow business reasons we're doing the best we can to prevent that eventuality from ever happening.

To protect their own business interests, publishers (and their technical accomplices) have invented crippled digital formats that try to destroy the most fundamental and beneficial advantages of e-books: free transmission and duplication, and the ability of one library copy to be read by millions simultaneously.

We have built the library of Alexandria and made it big enough to serve the entire world, but instead of burning it down we just lock the door so that nobody can get in.

<comment><USER5> Sure, but how are writers to get paid? It's hardly the most lucrative business to start with.

<comment> VvR-Ox Probably like musicians and a lot of them use platforms to publish their songs to listen to for free to gain momentum and attract enough people who will be delighted to get a Vinyl (in case of books it would be a hard cover).

When I personally used pirated stuff it was because I couldn't afford to buy it or there was no other possibility to get a digital copy that is easier to search and transport.

It is only greed that is stopping our world from becoming something with all the good features of series like "Star Trek" including access to all those books for free.

The greedy people think they can gain even more money by forcing poor people to buy their stuff by punishing them. The greedy who have money influence governments to make laws against this piracy and investigate against them with public money.

In the end the poor can still not afford to buy the books, music etc. and will just be punished which costs more public money than giving them free access in the first place.

This is just another thing that is very wrong in our world.

<comment><USER6> I think you should become the change you want to see in the world and stop charging for your work. I wonder how that will go.

<comment><USER7> A lot of people on this forum probably _are_ pretty happy-go-lucky with their negotiating.

The difference between $200k and $300k is a lot, but I see a lot of unattached young people not really caring. Ironically, it seems much smaller than the difference between $20k and $30k.

But most artists don't have people breaking their door down to compete for their time. And anyways, coding is a creative profession; I'm sure that plenty of techies are aspiring artists who didn't like their odds.

I'm surprised that more people don't see exclusively 'ex post facto' rewards as a sort of corrupting influence on the creation of art, rather than a motivator.

<comment><USER5> > The difference between $200k and $300k is a lot, but I see a lot of > unattached young people not really caring.

In which context do you see that?

> ex post facto' rewards as a sort of corrupting influence on the creation of > art

So ... Patronage only? Commissions only?

</comment></comment></comment></comment></comment></comment><comment><AUTHOR> I agree in terms of the economics of it for many readers at least. I buy a lot of books. I would buy a lot more e-books I think if prices were reasonable i.e sub $5, vs. usually being as much a print copy. I also gift many books. I recently downloaded 200+ books via b-ok.org...most of which I certainly wouldn't have bought and probably half of which I won't open for years if ever. Two months later, though, a couple of the books I enjoyed that I've ordered new copies to be sent as gifts as friends.

I would be a good candidate for something like Kindle Unlimited, but most of the books I'm interested in aren't available there. At least half the books I downloaded (many academic as well as poetry and other books) are not available on Kindle Unlimited.

Subscription music aggregators seem to have a pretty decently comprehensive offering in a way that the book, news, and movie aggregators don't.

It would be a little weird, but if there was an app where I could read any book but every 20th page or so was some full page ad...I could live with that (as long as it wasn't a video or something). Not sure if that kind of a model could work in terms of the economics for writers -- but it's of course working for news mostly and for some film sites like Tubi and Pluto.

<comment><USER8> Have you checked Scribd? They might have some of those that Kindle Unlimited doesn't.

</comment></comment><comment><USER9> Safari Books Online (I think recently rebranded as O'Reilly Online) is a pretty decent value -- about $49 USD a month for access to most O'Reilly, PragProg, Manning, and quite a few other non-programmer focused publishing houses like Academic Press. Between that subscription, my scribd subscription (which has plenty of unauthorized titles in addition to its authorized titles), and PDFs I'm able to find elsewhere, I'm pretty set. (not affiliated with either OReilly or Scribd, just a happy user)

Despite this, I strongly prefer a physical copy. Except for some of the books on Safari which I use as a quick reference, I mostly use PDF copies as a sort of extended preview before purchasing (or not!) a physical copy

But the interviewee is spot on when he argues that a pirated download != a lost sale. The idea that it is is just pure silliness. Before I got into tech, if I couldn't find a PDF of a $70-120 book I simply wouldn't read it. Period.

<comment><USER10> I tried Safari/O'Reilly Online and I think it is too expensive.

The time I can spend every month for "extra" reading translates to roughly one book. For 49 USD a month, I could just buy the book secondhand every month (and even sell it further when done).

I would have happily paid 5 USD a month, but 49 USD, that's way too much for the value, for me.

<comment><USER11> I wish they had pricing based on countries PPP instead of a flat international pricing, it's kinda expensive if you're not from a first world country cause atleast where I am, $588 (49x12) would easily pay for a semester of college. O'Reilly does have local reprints of the books for slightly cheaper through their partners here but I wish they would also implement a similar pricing discount for Safari

</comment></comment></comment><comment><USER12> Similar to books, growing up in India I discovered "Western" music because of pirated music. The one and only reason I heard of bands like Yes, Jethro Tul, Roxy Music, Steely Dan, Dylan, Joni Mitchell, or St. Martin in the Fields, etc. are the pirated copes moving from hand to hand among our school buddies. There was no way we could have afforded the orginal copies from the publishers.

Well the clocks ticked, I came here for graduate school and but the time I got my first job, over a period of time I had instinctively purchased all the original CDs and Box Sets of these and many other artists, about 1000 of them on my shelf. When I exchange notes with with my old buddies, some in Canada and some in England, they have more extensive collections than me. For one weak immitation of a Gibson lookalike guitar we had, we own a small stable of the real things by now :-)

The pirated copies that hooked us to the artists in the first place. I hate to steal from the artists I so much adore, but then shouldn't there be a way to spread the music around.

</comment><comment><USER13> Book piracy is a big reason I've been able to learn as much as I know about ML.

I don't know how to feel about it. All I know is that I'm more effective than I would've been if I had to pay for the books, since I wouldn't have read anything.

It's common on HN to pretend that everyone here is an affluent programmer working for FAANG with $500k/yr in stock vesting. In reality, I've spoken to many who are more along the lines of "month to month paycheck." Dropping $50 on a book about Tensorflow just isn't in the cards.

Yet the outrage is extreme, and probably justified: [https://news.ycombinator.com/item?id=18047297#18049297](https://news.ycombinator.com/item?id=18047297#18049297)

I apologize to the authors of the books I've absorbed. No doubt you've worked exceptionally hard. For what it's worth, I do recommend your books to others who may be in a position to buy them.

I like:

\- Hands-on Machine Learning with Scikit-Learn, Keras, and Tensorflow, 2nd Edition

\- IPython Interactive Computing and Visualization Cookbook 2nd Edition

\- Nick McClure - TensorFlow Machine Learning Cook (2017)

These are easily found on Library Genesis, which has become my de facto study.

<comment><USER14> "Buy or pirate" is a false dichotomy when there are good public and University libraries available; which is true for most big cities in the US. They will not stock the latest tech books, but you can easily get them through an interlibrary loan.

<comment><USER15> If the book is freely available from a library does it really matter if you find it more convenient to get it by pirating?

<comment><USER16> Sure, but libraries must buy books to loan. For physical books, there's only one concurrent user. And for ebooks, licenses specify allowed numbers of concurrent users.

But still, that is an interesting argument.

So why aren't libraries considered to be pirating?

<comment><USER17> IIRC, there have been that claim: Libraries, of course, were going to put book publishers out of business because all of their patrons were reading books they otherwise would have purchased. We simply don't hear of this pushback much anymore and we more see it as a public good - though not always good enough to fund them properly or make sure everyone has access to one for free.

<comment><USER18> It's more complicated than that; in the 19th century when libraries (at the time mostly subscription ones akin to a Victorian Netflix) were the primary purchasers of books rather than individuals, novels were extremely expensive -- the typical novel at the time was a rambling 1000+ page affair taking up three volumes [https://en.wikipedia.org/wiki/Three- volume_novel](https://en.wikipedia.org/wiki/Three-volume_novel)) and cost over 30 shillings. That's like £150 or $200 today! It was the decline of the subscription library that forced publishers to sell books to individuals at a more reasonable price and eventually invent the idea of the paperback

</comment></comment></comment></comment></comment></comment><comment><USER19> I can sympathize with the desire to see your favorite books put online for more people to read.

I for example, am a big fan of the book "Waves & Beaches" by Willard Bascom, a long out-of-print book on the physics, dynamics of the ocean (and the spirit of longing to understand the nature of the sea), but which always only could be found for >$30 on Ebay or something like that.

I finally bought a copy (out of nostalgia) and actually enjoyed it again so much, I went to the trouble of sawing off the spine, scanning it and OCRing it to produce an eBook and prolong its life. For myself.

I have been tempted to share it, but have no idea how. But I imagine there's tons of books and people like this.

<comment><USER20> Upload to libgen is the best way to share things like that.

I'm not goint to upload the latest JK King Grisham page turner but an obscure gardening book where the author is long dead? Yes that is getting uploaded.

For the culture.

<comment><USER21> "Waves and Beaches" (1964 edition) is already in libgen.

<comment><USER22> No OCR.

<comment><USER19> Thanks, I'll have a look at that site and maybe upload it. I have the 1980 version which comes with a bunch more content about energy production from the sea.

</comment></comment></comment></comment></comment><comment><USER23> A thread from 2013: [https://news.ycombinator.com/item?id=4992595](https://news.ycombinator.com/item?id=4992595)

Discussed at the time: [https://news.ycombinator.com/item?id=1078652](https://news.ycombinator.com/item?id=1078652)

<comment><AUTHOR> Thanks Dang for posting the links -- interesting!

</comment></comment><comment><USER24> This title just wants me to still throw a useless stone in an already lost battle: "book piracy" used to mean "Steal a book content and sell it putting you as the author". That's the original meaning of the word.

Copyright-infriging a book does not sound as serious as "piracy" or "theft" but these two words are actually misused.

</comment><comment><USER25> The publisher who does three of a four part series but not part four (ipr dispute with right holder usually)

The author who is dead, has one seminal work online and four other not online. (Randolph Stow)

The author who is dead, has four minor works online but not the seminal work (c.m. kornbluth)

The author who is in dispute with epublishing as a protest against ipr contract terms (Ursula le guin, Philip Pullman) and has their work ripped anyway.

The bad OCR conversion.

</comment><comment><USER26> I buy a lot of books, more than what I read. But I have to confess that the lack of pdf versions and the sometimes obscene cost of text books does sometime lead me to peruse alternatives.

</comment><comment><USER27> Interesting that in the old linked discussion from 2013, someone claims that publishers can't complain, because they had a record year financially. I wonder how well they are doing now.

My gut feeling is that publishers these days face problems not from privacy so much as from 1) the sheer glut of content, making it hard to stand out, and 2) shortening attention spans and people preferring to read snackable content on their phones instead of longform books.

When Kindles appeared, they seemed to augur a golden age for reading (and sure, you could load them up with pirated ebooks). Nowadays I am conscious at the beach or on public transport of usually being the only person with a Kindle while everyone else around me is looking at their phones, and it would be hard to believe any significant number have an EPUB reader open on those phones to read actual books.

<comment><USER28> I bought one of the first Kindles and loaded it up with a hundred DRM- liberated ebooks and read it avidly. Since then, phones have gotten bigger screens with higher pixel density and longer battery life, and my Kindle now sits is a drawer unused. The best ebook reader is the one you have on you.

<comment><USER27> Higher battery life? The Kindle battery lasts much longer than a phone with the backlight off and in airplane mode.

But again, even if a phone _could_ be used as an ereader, my point is that for most people it is likely not. Even for bibliophiles, they might not get so much reading done on a phone due to the distractions that phones bring.

<comment><USER28> I meant battery life is now longer on phones than it used to be on phones, assuming you're using it as an ebook reader, which means no radios.

<comment><USER29> That still can't be compared to an average eReader, whose battery lasts for weeks.

I charge mine every two or three weeks (about an hour of usage per day).

<comment><USER28> Of course it can be compared.

</comment></comment></comment></comment></comment></comment><comment><USER30> It's funny to think that I do books translations so others in my country (or for those that know my language) can read them, most of them pirated books. I sometimes ask my self how much would I earn if publishers would pay me for that work.

Anyway, it feels good to know that someone got his(her) exams fine, school homework done or just a pleasant read because some of my work. This is my contribution to the humanity. The invisible spark of information freedom.

</comment><comment><USER31> I'm torn on the topic myself. I buy books, because I'm fortunate enough to be in a financial position to buy the books I want to read.

But e-books are comparatively expensive. They were conceptually sold to us as a cheaper alternative to hardback and paperback books; but they cost as much as hardback editions quite often. For no reason other than "the market will bear it". The market may technically be bearing it, but it's caused a segmentation of that market with piracy on the other side of the line.

Technical books are even more ridiculous; $50 for a book is insane in this day and age. Especially when it's a distilling of topics and subjects easily found online for free. The act of distilling is not worth $50 to me. "Physically Based Rendering" is probably the only technical book I've purchased and felt good about purchasing; and that's because it feels like a full college course in the subject.

And then there's the college textbook scam. I feel morally incapable of supporting that racket in any way, shape or form. It's an egregious abuse of a captive audience that forces purchases at prices which are based on what can be gotten from a college loan, not in the value the textbook may provide.

<comment><USER4> Textbooks are definitely a scam, and often the authors don't make much money from them - it's eaten by the publisher and distributors.

A number of e-books on Amazon are priced at $9.99 since Amazon pays a higher royalty rate for prices under $10.

</comment></comment><comment><USER32> I stopped buying books when I realized that I don't really read most of them (blame short attention span). So I pirate a lot of books, which also, for the most part, remain unread. If I read a book and really like it, then I'd look at buying a DRM free ebook copy of it. I also buy ebooks when they're on sale at a low price.

</comment><comment><USER33> The problem where I live and studied, is that libraries state and book stores has deteriorated in the last few years for obvious reasons. At the same time it became difficult, or actually, impossible, for a privacy conscious person to buy ebooks online.

</comment><comment><USER34> I will sometimes try to locate a pdf of a technical book I am interested in. If I find it, I'll scan through it and if I think it's something I would like to read I'll buy a physical copy. If not, I delete the pdf and don't read it. If I don't want to buy it, it isn't worth my time to read it free.

It's my equivalent to walking into a book store and thumbing through books until I find one I want to buy.

</comment><comment><USER35> I read like 70 books per year, of which about 60 in pirated form on my Kindle. I never had any qualms with it.

</comment><comment><USER36> One thing that might lower piracy is making Amazon book previews not absolutely useless. If I preview a book and I can only see the million word introduction by someone who isn't the author, I'm not buying the book. The "surprise me" thing works ok but isn't available on most previews.

<comment><USER37> You can usually get a usable preview on the Apple bookstore.

</comment></comment><comment><USER38> This is an old story and much has changed since. You can find just about any technical title in seconds, and in clean pdf format - not scanned.

</comment><comment><USER39> I downloaded several thousand ebooks and read about 10 of them. I've also bought more ebooks than I've pirated and read, and the ones that I didn't read barely even happened... just a transfer of bits from one drive to another.</comment>


Twice - <AUTHOR> http://blog.aubrey.me/ <comment><USER2> The genius here was Bill Nguyen turning a failing company and a pittance $11mm offer from one failing company (Nokia) into an $80-160mm buyout from a real company (Apple), essentially though hustle alone.

But it's zero-sum genius. I can respect him for being good at playing a specific game, but it's not a game I want to play myself.

<comment><USER3> I struggle to even respect it. He ripped them off; the world would be better off without his "hustle".

<comment><USER4> He ripped nobody off, he sold a company in the exact way you're supposed to sell a company or for that matter the exact way you sell anything with a limited supply. Heck thats how you sell a house.

Step 1. Find interested parties, Step 2. Get Bids. Step 3. Allow other interested parties to counter.

Thats it there's no scam here. Its not even genius its company selling 101. Everyone involved had the opportunity to do their due diligence. Instagram did the exact same thing turning a $500M Twitter offer into a $1B offer from Facebook.

<comment><USER5> In my mind what you call "company selling 101" is just a legal, high level form of profiteering.

<comment><USER6> It's an auction. Profiteering (price gouging) applies to commodities, which already have a market price.

Not even really zero-sum, because selling it to the person valuing it the most (to whom it is most useful) does create value.

But it's not as satisfying as _making_ something that never existed before.

<comment><USER7> _commodities, which already have a market price_

Balls. Go to a commodity exchange and you know how you find the price? The last price paid at auction.

Sometimes the negotiation is disguised, using an order book or dealer system.

But sometimes they even explicitly run a call auction.

All Wall Street is is a continuous auction house.

All Supply/Demand is is a continuous auction.

</comment></comment></comment></comment></comment></comment><comment><USER8> Fascinating story.

Fast Company did a piece on Bill Nguyen about 18 months ago: (<http://www.fastcompany.com/1784823/bill-nguyen-boy-bubble>) and included an infographic on his track record:

[http://infographics.fastcompany.com/magazine/160/bill- nguyen...](http://infographics.fastcompany.com/magazine/160/bill-nguyen-track- record.html)

For a bunch of companies that have widely been considered failures in terms of product and number of users, he has had some unbelievable exits and financial successes.

<comment><USER9> Keep in mind most acquisitions for product integration kinda fail, well at least most of the acquisitions I hear off. The company I work for is small printing co, they made a small acquisition (sub $2M or $3M)a few years back, I doubt they got more than $500k in revenue from it.

</comment></comment><comment><USER10> The point of this post is to talk about Bill's hustling when selling Lala, which is a very interesting story.

The author should have left the last word out to make a much more powerful story about Lala rather than changing the focus of the article to Apple's "genius," especially since there was no genius involved on Apple's part. Just good luck for Apple, and horrible luck for the Color team.

<comment><USER11> I disagree. I thought the last paragraph was great. Life is never a single event. Round 1 to Lala and their engineers. Round 2 to Apple. There'll be Round 3's!

<comment><USER10> I agree, the last paragraph is great. My issue is with the last word. A better ending might've been something along the lines of "Paying twice cost less than paying once," and left out characterizing this fortuitous win as a "genius" strategy.

<comment><USER12> English isn't my first language and I really have a hard time grasping the meaning, the subtelty, of the end of the article.

Does the author say: "Apple bought some employes for a high price ($80M). Later, those employees left Apple for another venture. But when leaving, those employees also left some kind of shares/bonus or something very valuable they obtained by being acquired earlier. They were acquired again later (color) for a much lesser price so in the end they "lost" some money/shares/opportunity".

Have I got that right ?

<comment><USER13> The Lala acquisition was worth a total of $160M. $80M up front, and $80M as an earn out (over time). When they left Apple early to do Color, they lost a huge chunk of that $80M (earn out money) because they left early before receiving it (vesting) which in the end was worth a lot more due to increase in stock value. Apple bought Color (and those same engineers returned to work at Apple) for a lot less than what they would have paid in the earn out had the engineers stayed and not leave for Color in the first place.

<comment><USER12> Thanks a lot for taking the time to write it down for me! Much appreciated :)

This makes much better sense to me now.

</comment></comment></comment></comment></comment></comment><comment><USER14> The title of this is a little misleading as I don't really discuss anything about Apple acquiring Color. I just link to the rumor articles.

<comment><USER15> thanks for adding that - i read through it three times trying to find a link to page 2 or something. :)

</comment></comment><comment><USER16> I miss Lala, at least the final streaming iteration. It had iTunes Match for FREE years ago. You would upload your library to Lala, they would decide what they already had and just let you stream that, then anything they didn't have would get uploaded. It was iTunes in the cloud. Their webapp was phenomenal, especially by 2009 standards.

I had big expectations for Lala after Apple bought them. I thought they might actually get a true iTunes in the cloud built.

<comment><USER17> +1 to this. I am on Rdio now for $10/mo, and I easily would have paid Lala the same monthly fee for their service.

I assume they were in bad shape because they had to pay every time someone streamed a song, and not enough of their users wound up paying them for streaming access. Too many loss leaders.

<comment><USER18> What I liked about LaLa is that you didn't have a monthly fee, and browser- only purchases were dirt cheap, $0.10 for most songs if I remember correctly. I don't listen to enough music to make Radio or Spotify worth it for me, but I could buy a couple of albums to listen in the browser for 2 or 3 dollars every now and then.

</comment></comment></comment><comment><USER19> Looks like the post has disappeared from Aubrey's blog.

Google Cache of his original post: [http://webcache.googleusercontent.com/search?q=cache:blog.au...](http://webcache.googleusercontent.com/search?q=cache:blog.aubrey.me/twice)

Gizmodo also has his post mirrored: [http://gizmodo.com/5977076/the-amazing- story-of-how-bill-ngu...](http://gizmodo.com/5977076/the-amazing-story-of-how- bill-nguyen-sold-two-companies-youve-probably-never-heard-of-to-apple)

</comment><comment><USER20> _Google was worried, they moved fast._

This is what I'm unsure about: how much of google's worries was a result of Lala being a worthwhile company and how much of it was a result of Bill's propping it up? Let's remove Bill for a minute. Let's say Mr. No-name-CEO reaches out to his contact at Google and presents the deal for Lala. _My_ gut would be that Google guy would likely simply pass on the deal because he doesn't perceive Lala to be much of a competitive threat or a great product, not to mention the little traction they may have had was a result of Google's partnership(which I'm assuming they could easily opt out of). What am I missing? What made google worried, lala inc. or lala inc. with a salesman CEO with an acquisition offer?

<comment><USER21> Mr. Nguyen appears to be a hotshot startup salesman. Much like the proverbial car salesman, he can pump up something, sell it to a sucker, and pocket the commission.

</comment></comment><comment><USER22> He was relieved of day to day activities by the board about a month or more before the Apple acquisition...was that acquisition really his doing?

</comment><comment><USER23> I do not understood the tale :(

Why it was genius?

<comment><USER24> Those employees were given options at Apple ($80M worth) that were probably lost once they left the company to work at Color. Then Apple ended up getting them back on the cheap. So instead of $160M, Apple ended up paying $80M + $7M.

<comment><USER25> Doesn't the notion of this being genius imply that Apple "let them get away" the first time because they knew they'd be able to acquire their next company for less? Or am I missing something?

<comment><USER26> Its a very sycophantic article that gives Apple far too much credit. No "genius" strategy was involved it was just fortunate (for Apple) that they could acquire the remnants of Color for such a low price.

<comment><USER27> I don't understand.

They bought Lala. The sought-after employees left even after being offered a $80M golden leash.

They were bought again with Color. What stops these employees from leaving again, with a much less lucrative golden leash this time around?

<comment><USER26> Nothing stops them from leaving again. My previous comment was just taking issue with the article describing the move as "genius"

<comment><USER28> Seems to be a common trend with pro-Apple articles. Earlier I read one that credited Metro-style design to Retina displays.

</comment></comment></comment></comment></comment></comment></comment><comment><USER29> Fascinating story but how is Apple genius here? Was it Apple's all along to acquire Lala, let Lala's engineers go before they exercised their options, somehow made Color a failure, then bought the all the engineers back on the cheap? The real genius (or at least real good biz person) in this story is Bill Nguyen, Apple just did what makes sense for them, it just happens that two of their acquisitions are Bill's companies.

</comment><comment><USER30> No mention of the Color in the article, I guess but that was a great story.

</comment><comment><USER31> This is how the Finance people in NYC interview for a job. Give them a number and they'll shop it around and start a competition. :)

</comment><comment><USER32> The piece was removed for some reason?

</comment><comment><USER33> Why is this top link?

<comment><USER34> Because 70 people voted it up.</comment></comment>


Bypassing Google's authentication to access their Internal Admin panels  - <AUTHOR> https://medium.com/bugbountywriteup/bypassing-googles-fix-to-access-their-internal-admin-panels-12acd3d821e3 <comment><USER2> Sounds like a fun one to find. Good on him for digging around. I could totally see how this oversight would happen too, with the engineers working on a secure auth system but not thinking about a proxy or caching layer that might expose them.

<comment><USER3> It's intriguing though because it seems like the sort of thing Google is expressly focused on from a security standpoint. Essentially the problem here was that access was limited to Google's own network, but Google has repeatedly talked about how they no longer consider their own internal network secure. (See also: Anything about BeyondCorp.)

That being said, from the looks of this interface's channel-based settings, and the mention of YouTube TV, my guess is this is some classic telecom- industry hardware, and Google may have folks from the TV broadcasting industry working more heavily on this particular arm of the organization.

It doesn't much look like an interface Google itself designed, so they may be more limited in how they can lock it down.</comment></comment>


Ask HN: Following up on GPL violation of my own software? - <AUTHOR>

I'm interested in guidance here based on actual knowledge/experience, rather than just peoples' opinions.
Here's the story:
I am the author and copyright holder of some GPL software.  Even though I don't think I'm losing money because of the violation, I feel a duty to stand up for the GPL, so I do want to follow through.  I don't see instructions on how to do that here: http://www.gnu.org/licenses/gpl-violation.html
My GPL software's home page is here: http://ifdefined.com/bugtrackernet.html And a demo here: http://ifdefined.com/btnet/bugs.aspx
The company that I believe is violating my license is here: http://ibn-distribution.de/sbhd/
I have zero doubt that their software uses my codebase, but I'm not 100% sure that they are failing to open their source, as mandated by GPL. So, I contacted them directly using two different email addresses I found on their site, but I have not heard back. I wrote that I want to work with them to make sure they comply with GPL OR work with them to license my software under different terms.  I don't care which, but as I said, I feel it as a duty to follow up.
What should I do next? <comment><USER2> I believe a similar question was asked on Slashdot a while back. Someone had some GPLv2 code that another company was selling. The general response was that it was completely legal, because the company only had to disclose the source code to people who bought the product. Source had to be made available, but it's not so strict as to "publicly available."

I'm not a lawyer so I'd go with one of the links posted for software legal advice.

</comment><comment><USER3> The first step is to understand the terms under which you offered your code. Unless you have purchased the software from them and requested the code and they failed to make it available to you, or they have publicly made available their software and you've requested the code and they failed to make it available to you, and you've given them reasonable time to reply to these requests, there's no evidence of breach of the license yet.

<comment><AUTHOR> Right, I understand that. At this point, they haven't responded to me at all.

<comment><USER3> If they're selling the product, then they only have to provide the code to the customers. I could be totally off, but that's my understanding of the GPL -- it creates an obligation to share the code with whoever you distribute it to, not to everyone. In that case, they have no obligation to ever respond to you unless you paid for a copy from them.

</comment></comment></comment><comment><USER4> Have you asked them for a copy of the source?

They are only obligated to give out the source if someone asks (if it's not available with purchase/download).

<comment><AUTHOR> Right. Understood.

</comment></comment><comment><USER5> I suggest asking for advice from the Software Freedom Law Center: <http://www.softwarefreedom.org/> They specialize in this kind of thing.

As a point of ... trivia? ... Eben Moglen, the attorney that created the GPL along with Richard Stallman, directs and is a founder of SFLC.

</comment><comment><USER6> Call the company via phone. Most Germans speak English, so that should work.

You might want to take a look at <http://gpl-violations.org/> the guy who runs it is also a German.</comment>


The 10 Skills You'll Need by 2020 - <AUTHOR> http://www.careerfaqs.com.au/news/news-and-views/the-10-skills-you-ll-need-by-2020-and-beyond/?utm_source=prosperity&utm_campaign=prosperity_september_2016&utm_content=future_skills <comment><USER2> I feel like these aren't _that_ substantially different to things that have been useful since the stone age, slightly repackaged.

Further, "by 2020" is a bit of a misnomer; these things are currently very useful.

</comment><comment><AUTHOR> Self-driving cars, artificial intelligence, quantum computing — these are no longer the fantasies of sci-fi authors or Hollywood directors. This is the reality of our future, and the future is almost here!</comment>


Could You Power Your Home with a Bike-Powered Generator? - <AUTHOR> http://www.npr.org/sections/13.7/2016/12/08/504790589/could-you-power-your-home-with-a-bike <comment><USER2> This bike may be the closest yet to doing something like that. [http://www.treehugger.com/clean-technology/5-hour-energy- cre...](http://www.treehugger.com/clean-technology/5-hour-energy-creator-roll- out-pedal-powered-energy-solution- india.html#14812499440661&action=collapse_widget&id=0&data=)</comment>


Linus Torvalds Sees Lots of Hardware Headaches Ahead - <AUTHOR> https://devops.com/linus-torvalds-sees-lots-of-hardware-headaches-ahead/ <comment><USER2> >Moore's Law has guaranteed a doubling of hardware performance every 18 months for decades. But as processor vendors approach the limits of Moore's Law, many developers will need to reoptimize their code to continue achieving increased performance.

But Moore's law is dead for long time already. I'm using mid-range CPU from 2009 and performance is still reasonable. (while 1999 CPU in 2009 would be rather useless)

<comment><USER3> I think a part of this is that we hit a bottleneck on human data absorption. There's lots of real and hypothetical media formats (like VR) that won't run on a 2009 computer. But so long as you've got your email and websites and video, your machine is still perfectly useful. New computers are doing all those same things. But I remember when the concept of a video running on a computer was just wild.

</comment></comment><comment><USER4> Wirth's law is relevant for how software is constantly outrunning hardware.

I'm quite pessimistic but I'm sure a lot of stuff involved with os and ui and browsers will have to be thrown away, and built again.

The fact that js doesn't really run well on smartphone proves something is wrong.</comment>


Ask HN: Secure, reliable data backup solution? - <AUTHOR>

I am looking for a solution to back up daily trade logs.  These are VERY important.  Normally I would print out and keep hardcopies, but there's way too much data for that, so I will have to maintain an all-digital backup.
It should be:
- Secure (encryption, physical security, etc)
- Reliable (hopefully >3x replication -- I
currently maintain 3 copies on 3 separate devices)
- Accessible (I don't need instant access, but if I need to recall the entire database I should be able to get it within a week)
As far as price is concerned, nothing too egregious.  To put a price point, lets say 2000/mo. <comment> mike-cardwell Get a few dedicated servers wherever you want and use Duplicity: [https://grepular.com/Secure_Free_Incremental_and_Instant_Bac...](https://grepular.com/Secure_Free_Incremental_and_Instant_Backups_for_Linux)

</comment><comment><USER2> Maybe tarsnap?

You can do a write only key on the server and backup that way then keep the read and delete key off of that and use that only if you need to restore/check backups.

Depending on how much you are backing up it will probably be less than 2000/mo and it is hosted on s3 so there is quite a bit of reliability there.

<comment><AUTHOR> S3 concerns me quite a bit ..

<comment><USER3> What concerns you about S3?

<comment><AUTHOR> Reliability. Though that may have been other parts of AWS</comment></comment></comment></comment>


Ask HN: Should we keep building this cloud managed tablet for the classroom? - <AUTHOR>

We had this vision of a turn-key tablet solution for K-12 educators. We are forking Android to add cloud device management for the teachers to install/remove apps from students device, restrict when students are allowed to play games, and what website students can access. It will also have a school friendly app store that allows the school to purchase app and ebook licenses for all their devices, and push app installs to all of their tablets through the cloud.
After doing some research, some schools who rolled out tablets to their students allowed their students to manage their own devices. They decided to educate the students on whats appropriate rather than restricting their tablets.
Now we are not sure if we are solving the right problem any want to manage their students' tablets. HN, what do you think? <comment><USER2> We must work in similar industries. We had, and scrapped, a project do to nearly exactly what you are describing. It felt like this was the next logical step for us: we had experience in hardware, embedded linux, android and have good relationship with prominent distributors.

However, it was still a big big task and we'd never get close to competing on price/quality. Also, we discovered the same thing when talking with schools, they were letting students manage their own and adopting new policies to regulate their use.

We're focusing on software now.

</comment><comment><USER3> This maybe appropriate for middle school and younger kids. As kids go to high school they should be capable of making responsible decisions and not have 'big brother' monitoring them.</comment>


You Don't Find Bugs in Legacy Code - <AUTHOR> http://www.davidtanzer.net/you_dont_find_bugs_in_legacy_code <comment><USER2> As someone that has spent the last two years migrating legacy code, I can assure you, you do find bugs in legacy code.

I've seen bugs that user's don't notice.

I've seen bugs that user's have just gotten used to.

I've seen bugs where that failures it caused were dismissed as the system being a bit temperamental, for many years.

I've seen bugs that financially affected thousands of customers, and remained unnoticed over the course of several years.

I've even seen bugs that only remained because, by luck, the preconditions to trigger it had not been met.

I can assure you, you do find bugs in legacy code.

<comment><USER3> And yet, by fixing any one of those, you'll probably break something else. Something that relies on the broken behaviour, or 'corrects' it.

Any bug in a large codebase that's older than a certain point becomes a feature. ;)

<comment><USER4> [https://xkcd.com/1172/](https://xkcd.com/1172/)

<comment><USER5> And that's how we got Spacemacs.

</comment></comment></comment></comment><comment><USER6> Quick website comment: If you're going to ask if I want to subscribe to your agile development course _and_ your newsletter, I'd prefer if those popups came at the same time rather than several seconds apart. It's annoying enough to get one such popup.

<comment><USER7> If you read the article with NoScript installed in default deny mode, you get _zero_ popups while reading the whole article.

</comment></comment><comment><USER8> > None of the business analysts could remember what this statistics feature > was used for, so we tried to find out who uses it. We looked at the logs of > the last 6 months and found out: It was never used! Not a single time!

I've seen a lot of similar stories. General advice: if you want to find out whether anyone really uses something, the relevant time span is a year and a day. It's theoretically possible longer would be needed, but a year and a day will cover almost all cases.

<comment><USER9> Very good advice, especially for obscure features. If the feature was only used when filling out some field on the annual tax return for example, then no one using it for the past 6 month could be perfectly reasonable if you pick the wrong 6 month period.

</comment></comment><comment><USER10> If you find a feature nobody has used for the last 6 months... and its to do with some long term calculations... probably safe to say they use it annually. We have the end of year reports that generally kill the database when people try to run 5 years worth of data through them every christmas... they never touch them during the normal working year though.

</comment><comment><USER11> It's only mentioned in a single line, but there are a lot of real bugs in legacy code that the users actually learned to live with. It's the software's personality now. And when someone has learned to live with a bug, it will be missed if it is suddenly not there any more.

In the past I considered that a bug in human behaviour, but actually it is admirable. You give people a broken tool, but instead of failing, they find a way to succeed using that broken tool. And of course after the effort they are not as willing to change to anything else. Don't change a running system and such.

</comment><comment><USER12> "Legacy" is a very loaded term -- generally used in a derogatory way.

There is an old engineering truism: "if it ain't broke, don't fix it"

When Lindbergh flew across the Atlantic in the Spirit of St. Louis, the Wright Aviation Company which made the engine for his plane, wanted to do its best to make sure he made it. They carefully built and checked the engine and hand delivered it with a note: "don't monkey with it" (or words to that effect). Lindbergh was a careful guy and he didn't.

Businesses and developers need to distinguish between warranted or needed changes to working systems (software or otherwise) and ego trips.

Real systems are built in limited time, with limited resources, even if they have a multi-billion dollar budget. Invariably there are things someone can make an issue about even in a system with a perfect performance record. Why did you hard code 3.14159267 instead of having a general variable for PI initialized to 3.14159267, and by the way why do you have only 8 decimal places -- wouldn't 16 be better? It is an ego trip and it is the ancient territorial imperative, marking your territory by deprecating the previous person or team -- or a colleague.

Joel Spolsky wrote a famous and widely ignored blog post on this sort of thing:

[https://www.joelonsoftware.com/2000/04/06/things-you- should-...](https://www.joelonsoftware.com/2000/04/06/things-you-should-never- do-part-i/)

Take a deep breath and ask yourself: is this something we _really_ need to do or am I (are we) showing off/putting someone down/behaving like a spoiled adolescent?

<comment><USER13> In the sales community, "legacy" seems to mean "what we didn't sell you."

</comment></comment><comment><USER14> So users of old software may be aware of various defects and have changed their behaviour to make it work for them. It's important to consider the human element when "fixing" legacy software.

<comment><USER15> Aah yes, every change breaks someone's workflow: [https://xkcd.com/1172/](https://xkcd.com/1172/)

</comment></comment><comment><USER16> You can't really safely alter legacy code unless it had decent unit tests. Red/Green programming (test drive development) is absolutely essential in cutting down on technical debt.

<comment><USER17> Unit tests don't help you determine whether a given behavior is incidental or necessary. For a lot of code, including the statistics code in the article, correctness is a _dynamic_ property: dependent on its context, environment, clients, etc. So working with legacy code is as much project management and communication as it is engineering best practices.

Consider Chrome's recent change to mark sites as insecure if they have a password field without TLS. Will my grandma's bank page be reported as insecure? There's no way to know a priori, or through isolated unit tests. The Chrome team has to go out into the Internet jungle, reaching out to the site owners and pushing until the major sites are ready, and any holdouts can be considered acceptable casualties.

With that understanding, whether code is "legacy" isn't about age or budget or level of support; it's about how much influence you have over your clients. Some code is never used and so never becomes legacy, no matter how old it is. But other code is born legacy: it gets clients immediately and pays the price for being popular.

<comment><USER18> > Unit tests don't help you determine whether a given behavior is incidental > or necessary.

That's his point. If you have a test-case for the behaviour, you know that this is how it should actually behave.

Anything not covered in tests however, that will naturally be covered in uncertainty for any weirdness, quirks or odd behaviour. Should it be there or not? Hard to tell when it's not formalized in a unit-test.

<comment><USER19> Assuming they were testing behavior and not shooting for some coverage metric. I come across plenty of bugs with tests against them. I have a rather strict rule personally, every test should start with a line that says what it's testing.

</comment></comment></comment></comment><comment><USER20> The problem is that new code becomes legacy code about ten minutes after it is written.

</comment><comment><USER21> Hence why it's important to unit test legacy code using a mocking tool like Typemock Isolator</comment>


WhatsApp is not selling to Google - <AUTHOR> http://www.web-target.com/en/open-target/531-whatsapp-is-not-selling-to-google

<comment><USER2> "the head of development of WhatsApp, Neeraj Arora, has confirmed to AllThingsD that his company has not started any discussions with Google"

...merely gone along with the ones Google have started?

</comment><comment><USER3> I think whatsapp should integrate better with Android first (kinda like Facebook home). Then it would make sense.</comment>


HelpCode Is Solving Developers Bug's ( Ruby,JavaScript-Nodejs,RubyonRails) - <AUTHOR> http://www.helpcode.co <comment><AUTHOR> HelpCode is solving DevelopersBug's ( Ruby -Javascript - NodeJs - RubyonRails) for this month Free. they are doing a trial test to test. if you have a problem submit.</comment>


Amazing demo reel of Palantir visualization UI - <AUTHOR> http://blog.palantirtech.com/2009/09/29/the-palantir-technologies-demo-reel-screenshots-round-3/ Palantir has done some amazing work building high quality, meaningful visualizations backed by big data.  Really neat stuff, all in Java Swing! <comment><USER2> Maybe this demo reel makes sense to their target customers, but it made very little sense to me. Not sure if it really tells a story to members of the general population.

Also, I personally felt that the "eye candy" wasn't so impressive. Looked like any other ERP/B2B system out there. Aside from the criminal clip art and the maps, it might as well have been.

Music was grating after 30 seconds as well.

Still dig the company name though.

<comment><AUTHOR> This demo reel was culled from our myriad online workflow demos. You can find them linked off of our main website or directly on the two analysis blogs:

<http://www.palantirtech.com/government/analysis-blog> <http://www.palantirfinance.com/analysis-blog/>

or from the pfinance splash reel:

<http://www.palantirfinance.com/>

Seen as part of the demos they were pulled from, it will make more sense.

<comment><USER3> I liked it OK, but strongly suggest you either use a player with a volume control or process the volume on the music before you make the flash, especially if you're going to use dance music that stays pinned in the red :)

</comment></comment></comment><comment><USER4> There are a bunch of these kinds systems in the government. Palantir's tech is pretty cool and a nice spin on the area (besides looking nice and slick). But hardly new.

It takes a lot of cues from mish-mash systems like this one (warning PDF)

[http://www.cjmtk.com/EventRegistration/CjmtkConf08/DCGS- A_MF...](http://www.cjmtk.com/EventRegistration/CjmtkConf08/DCGS- A_MFWS_Overviews_CJMTKUC.PDF) (a hodge podge of every conceivable analysis tool and database under the Intelligence sun)

And more unified systems like this

<http://www.futurepointsystems.com/> (their page stinks but their tech is awesomely cool)

and other single purpose tools like

<http://www.i2inc.com/products/analysts_notebook/> (industry standard link- analysis)

<http://tactical.overwatch.com/products/axis_pro.htm> (another recent link- analysis tool)

<http://www.esri.com/software/arcgis/> ( _the_ name in geospatial)

And others <http://spotfire.tibco.com/>

<http://www.oculusinfo.com/SoftwareProducts/GeoTime.html>

It's nice that they are expanding out into financial services and geospatial analysis. Up till now it's largely been a glorified (and very expensive) link- analysis tool (see i2's and overwatch's tools).

</comment><comment><USER5> The streaming didn't work at all for me. You can download it directly here:

<http://media.palantirtech.com/palantir_demo_reel_final.mp4>

<comment><AUTHOR> Yeah, I apologize that the flash player is a little fickle. The direct link is a great way to get at it, too. Thanks for posting that.

</comment></comment><comment><USER6> I can't believe this was written in Swing

<comment><USER7> Visualizations like that are one of the few things swing is awesome at.

</comment></comment><comment><USER8> I've seen these guys come up a few times over the years, and I think what they're doing is amazing. When I watched that video, I didn't just think "Wow, this is something cool" it was more of "I want to be involved with this". Working on the kind of stuff shown off in that video was just about as close to my dream job as I have ever seen.

On that note, I wanted to point out one screenshot in particularly, which just blew me away: [http://blog.palantirtech.com/wp- content/uploads/2008/07/hh-d...](http://blog.palantirtech.com/wp- content/uploads/2008/07/hh-dashboard.png). That has got to be one of the slickest, best looking interfaces I have ever seen. Some of the contrast is a little bad from a color-blind perspective (the titles for the widgets are very difficult to read), but the way they jammed so much information into a screenfull is amazing.

<comment><AUTHOR> We're hiring: <http://www.palantirtech.com/careers/positions>

We'd love to have as much help as we can get!

</comment></comment><comment><USER9> I got one of their free schwag shirts. It says, "You had me at hello world"

<comment><USER10> I got one that says "Save the Shire" and I have no idea why.

<comment><USER11> (They're named palantir, after the crystal balls in Lord of the Rings... so hence that shirt)

I also have the shirts too. Good addition to the collection.

</comment></comment></comment><comment><USER12> Seems to be only good for presenting data, not interacting with it really.

</comment><comment><USER13> I didn't know music this bad existed. WHY would you use it in a demo real?

<comment><USER14> You don't know Daft Punk? Have you been living under a rock?</comment></comment>


Campaign to Buy Browsing Histories of Politicians Who Passed Anti-Privacy Law - <AUTHOR> https://yro.slashdot.org/story/17/03/29/1717201/activist-starts-a-campaign-to-buy-and-publish-browsing-histories-of-politicians-who-passed-anti-privacy-law <comment><USER2> I think this is a little premature until we know what exactly can be purchased and when. As of right now throwing money at this person seems like just giving him free money. Who is this person and is he trustworthy... what's he going to do with the money if he can't buy it ? Does he even know how to buy the data ?

<comment><USER3> > Who is this person and is he trustworthy... what's he going to do with the > money if he can't buy it ? Does he even know how to buy the data ?

You've documented exactly why we should buy Congressional data. Let's make it painfully obvious that the data can be "weaponized" against them, their loved ones, and business partners by the unscrupulous and the unstable.

<comment><USER4> Public scrutiny of the internet habits of our elected officials probably isn't a bad idea anyway.

</comment></comment></comment><comment><USER5> I would add to this list Sen. Rand Paul, who co-sponsored the bill, but skipped the vote.

edit: link to donate to the gofundme campaign to purchase the browser histories [https://www.gofundme.com/searchinternethistory](https://www.gofundme.com/searchinternethistory)

<comment><USER5> edit #2: turns out im a dummy

[https://www.techdirt.com/articles/20170329/13234837037/no- yo...](https://www.techdirt.com/articles/20170329/13234837037/no-you-cant-buy- congresss-internet-data-anyone-elses.shtml)

<comment><USER6> Instead of an editorial techdirt article, do you have the law's text where the behavior is expressly forbidden? One of these things matters, the other has no bearing on reality.

<comment><USER5> I'm not sure your question has any bearing on reality?

There is no law that explicitly states that selling individualized internet search history is illegal. However, (and you would know this if you read the techdirt article) internet advertising marketplaces don't function that way. It's not that it's illegal, its just inefficient. The advertisers don't need to know WHO you are to know that their ad is relevant to you.

</comment></comment></comment></comment><comment><USER7> I think that the only way to really drive home the importance of digital privacy rights is to craft a bit of targeted advertising that _only_ your senator or representative sees and that follows them _everywhere_ online.

<comment><USER8> Why only senators? It would be an effective way to teach the public too. "Hi, <full name>. I know you live at <address>, and that <other facts>. If you care about privacy go to eff.org (or some other organization)."

You might also include a message along the lines of "everyone knows this information about you, it's just that we're the only one telling you that we know".

<comment><USER9> That's a great way to make the general public hate the EFF because they think it's spying on them.

</comment></comment></comment><comment><USER10> Actual link:

[https://www.searchinternethistory.com/](https://www.searchinternethistory.com/)

</comment><comment><USER11> Can I just sell my data? I really don't care and not sure why everyone is freaking out over this. I also believe most tech muggles don't care either. Also is not most of our data sold by data brokers currently - like your physical address. Not sure what I should worry about with my browsing data...

<comment><USER12> > Can I just sell my data?

That's the real issue here IMO. It blows my mind that Comcast et al thinks it's unfair that Google, Facebook, etc get to profit off of user data while they can not. I get that most politicians don't have the slightest understanding of tech, but how hard is it to understand that Google, Facebook et al get this access because they provide a service for nearly free with the cost being your personal information.

Comcast, Verizon, etc. sells a service that consumers purchase. Now they are increasing the costs by profiting off of our personal data while giving users nothing in return. Ironically, this gives them an unfair advantage. These corporate welfare queens don't have to compete by providing a service that I would pay for with my personal information.

</comment></comment><comment><USER13> Except the data is cleaned of personal information, correct? The top comments on the reddit thread of this issue are all about how this is impossible.

<comment><USER14> It is easier to deanonimize data than one would imagine (the work on the Netflix prize dataset comes to mind: [http://ieeexplore.ieee.org/abstract/document/4531148/](http://ieeexplore.ieee.org/abstract/document/4531148/))

</comment></comment><comment><USER15> Maybe both the politicians and their staff. Some of these old Luddites have never sent so much as an email in their entire life.

</comment><comment><USER16> Someone explain why I should fear ISPs more than Google? I can at use Sonic.net for privacy. I can't realistically opt out of Google. The lines seem arbitrary.

<comment><USER2> what.. this doesn't make any sense and I don't know what Google has anything to do with this. Why can't you opt out of google ?

1\. ISP monitor all your internet traffic. Google can only have access to what google services you opt in to use.

2\. At this time we don't know how the ISP's will sell your internet history whether it be individual or in aggregate, but google doesn't sell your information.

3\. I trust google's security more than ISPs

<comment><USER17> Google don't just have access to what you opt in to use. They also have access to whatever anyone else you communicate with effectively opts in to use on your behalf. For example, even if you don't want to give Google any data at all, there is a very high chance that they already have a lot of the emails you send via one of the other parties, and a fair chance that you won't even know it's happening unless you look at the MX records for their domain or something along those lines.

This is, IMHO, one of the biggest unresolved ethical issues with data protection and privacy today. On the one hand, it would be a great burden on society to stop everyone from using any third party services for anything involving personal data about someone else. On the other hand, when those services are no longer neutral and will process any data they receive _for other purposes_ without the informed consent of some of the data subjects, that's a dubious practice at best. Another example is a social network's mobile app uploading your phone's entire contacts list, and just like that they've probably got a unique personal ID and a great deal of networking information about everyone on that list.

<comment><USER2> while i don't disagree, you still have the option of not responding. Also I think what you mention is more of an issue with integrating systems with open standards. The alternative is using a closed system that only belongs to one vendor or revising the open standard to support privacy

</comment></comment></comment></comment><comment><USER18> Let them burn in a pit of there own dirty history!

</comment><comment><USER19> Something I read long ago (and can't find) was that privacy is a relatively recent part of humanity. In the past, we lived in small groups where everyone knew each other very well.

Now we live in big groups, which provide pseudo-nymity.

One of the things I keep coming back to in my head is a way to democratize the information collected about us. Right now, certain "people" (including companies and government organizations) have lots of access to lots of data and the rest of the population has very little access to that information.

Does privacy matter as much if we share observations as humans likely did in the past?

<comment> rm_-rf_slash Difference is these memories are no longer forgotten. Embarrassing stories may fall by the wayside back in the day, but think, your grandchildren will be able to look up your cringey college Facebook posts long after you've passed away.

<comment><USER20> You didn't have the kind of authoritarian powers we have with the ability to archive information about people.

We know what the statsi archives did... now there's unprecedented power to repeat that mistake at a larger scale.</comment></comment></comment>


Guesty (YC W14) raises $1.5M to expand its Airbnb management service - <AUTHOR> http://techcrunch.com/2014/06/16/guesty-a-property-management-service-for-airbnb-hosts-and-soon-more-raises-1-5-million/

<comment><AUTHOR> Hi HN Ceo and founder Amiad is here to answer questions</comment>


Quaternions: the Strange Numbers That Birthed Modern Algebra - <AUTHOR> https://www.quantamagazine.org/the-strange-numbers-that-birthed-modern-algebra-20180906/ <comment><USER2> Quaternions recently made me look pretty smart.

I was consulting at a company that's developing a VR real estate app, and the first thing I did was check to see whether they were calculating their rotations with quaternions.

It was easy to do, I just looked straight up and then turned my head to the right. My view rotated to the left, and I almost vomited. I immediately ripped the headset off and said, "You're using euler angles to calculate rotations, you need to use quaternions."

I felt pretty good about finding the biggest flaw in their system in 3 seconds.

<comment> a-dub Was it because of [https://en.wikipedia.org/wiki/Gimbal_lock](https://en.wikipedia.org/wiki/Gimbal_lock) ?

Apollo 11 engineers made the same mistake. :)

<comment><USER3> For Apollo, it wasn't so much a "mistake" as a conscious decision to save weight. The Gemini IMU used 4 gimbals, and so avoided the issue entirely. Apollo dropped the weight of the extra gimbal and instead required the pilots to avoid flying in certain orientations.

</comment></comment></comment><comment><USER4> I've found that the easiest way to understand quaternions is by visualizing them as scaled "look" or "orientation" vectors.

For example, if an airplane is oriented in the direction (x,y,z) at a rotation θ around that axis, then its rotation in quaternion form is cos(θ/2)+x sin(θ/2) i + y sin(θ/2) j + z sin(θ/2) k

Notice that the multiplications involving x, y, and z are just scaling the vector.

The other important thing to realize is that sin(θ/2) is greater than or equal to zero in the interval [0, 2*pi]. So a quaternion is just a look vector where the magnitude of the vector is determined by the rotation around the look vector axis.

See this page for a useful picture: [http://www.chrobotics.com/library/understanding- quaternions](http://www.chrobotics.com/library/understanding-quaternions)

<comment><USER5> Sort like monads I imagine as soon as you understand it you lose the ability to explain. I have given up "understanding" them and just try to understand when and where to use them.

<comment><USER6> That's OK! Do you think you _really_ understand the natural numbers?

<comment><USER7> That's a good question, actually. I'm Not OP, I'm sure OP "understands" them as much as anyone does. But considering that the most common definition is an incomplete extrinsic definition by example, _N = {1, 2, 3 ...}_ , I'd argue that in principle no complete extrinsic definition can be given :) That's more than a solipsism, because any number has inherent properties that make it different from all the others, even if these properties might be equal up to isomorphism with "n'th successor to zero", because then the system of isomorphisms is in question, begging the question ...

Whereas, if you know the intrinsic definition by the axioms, you know the definition, not the numbers. Big difference that is.

I'm keen on a distinction between numbers and forumals. If you take binary numbers and succ(), you have 0, 1 and an infinity of formulas. In my book that's only two natural numbers. We commonly change base to represent eg. 16 as 0x10 - or 1000 as 1k, requiring additional figures. Figure, number - potato, potato.

<comment><USER8> >I'm keen on a distinction between numbers and forumals.

What's the operational advantage of this approach? I feel like it would wreck havoc with fundamental tools like mathematical induction..

<comment><USER7> The difference between f(x)=...=0 and x=2, e.g. is quite huge for a lot of college students. The distinction between constants, operators and formulas is quite explicit in algebra. It seems to be a natural distinction to make. One advantage, I guess, is that a formula can be wrong, but a number can't, which is why proof by induction works at all.

<comment><USER9> How would a proof by induction work with only two natural numbers?

</comment></comment></comment></comment></comment></comment></comment><comment><USER10> I'm happy to see 3Blue1Brown's most recent video [0] get a mention in this article! He does a great job of explaining quaternions though visual intuition.

(I do think simply calling Grant a "math animator" is selling him a bit short. He's a true educator in every sense; animation is just one of the (very effective) learning aides he uses.)

[0] [https://www.youtube.com/watch?v=d4EgbgTm0Bg](https://www.youtube.com/watch?v=d4EgbgTm0Bg)

</comment><comment><USER11> My first interaction with quaternions was by applying the same principles used for Julia fractals, creating really fascinating artistic renders. The hardware was incredibly slow back then, so now I'm interested in experimenting again to see how this could be implemented in a shader.

[http://paulbourke.net/fractals/quatjulia/](http://paulbourke.net/fractals/quatjulia/)

The simple results above may just look like three dimensional blobs of taffy, but different rendering methods create some stunning effects. Additionally animating variations of these fractals is mesmerizing.

[http://www.bugman123.com/Hypercomplex/](http://www.bugman123.com/Hypercomplex/)

Hypercomplex fractals are simply beautiful.

</comment><comment><USER12> Alright, tomorrow I want someone to count how many times we see the phrase "the easiest way to understand quaternions is ..." on here.

<comment><USER13> I don't think that's a bad thing -- it's people trying to test their mutual understanding.

Here, destroy my inexpert one, and maybe I'll learn something: "It's like describing how to twist a ball, first with the direction used to spear it with a rod, an then how much to twist."

<comment><USER10> I rather inelegantly attempted to describe this as "a twisty and a pushy" to a friend today, while mimicking the animation with my hands. There is no work- appropriate way to do this. :|

</comment></comment></comment><comment><USER14> At the very least, you should open this web page just to see the weird rotating cube with ribbons on all 4 faces animation. I'm not sure if there's a visual trick there or not.

<comment><USER15> There's no trick. It's really unintuitive but it works.

<comment><USER16> Seems like the top and bottom ribbons would work. But the ribbons on the side get a kink every 2 rotations that the animation sort of sweeps under the rug?

<comment><USER17> They get a twist, but then loop around the cube, which undoes the twist. You can see their full orientation throughout the animation. (Or try getting your own cube and ribbons and try physically turning it to see for yourself.)

<comment><USER18> You can see the key behavior by fixing one end of a belt, and moving the free end.

You should find that there is a way to apply and remove double twists in the belt without twisting the free end.

</comment></comment></comment></comment></comment><comment><USER19> Numberphile's explanation of Quaternions is the simplest I have seen so far:

[https://www.youtube.com/watch?v=3BR8tK- LuB0](https://www.youtube.com/watch?v=3BR8tK-LuB0)

Quaternions are very important to know if you are doing any kind of 3D math. For instance, game programming or SLAM for robotics.

</comment><comment><USER20> As a 3d character animator I try to use Quaternions on very few bones, the problem with Quaternions is not being able to edit the curves as a 1 to 1 understanding of the axis. I mainly use the Quaternions for IK handles and the Root bone, the things that will rotate more than 360 degress.

<comment><USER21> > the problem with Quaternions is not being able to edit the curves as a 1 to > 1 understanding of the axis

Can you expand on this? What is the curve representing, and which axis do you mean?

<comment><USER22> Not the GP, but by axis they mean XYZ euler angles. In 3D animation software you typically have a set of curve graphs that show transformations vs time, that allow the animator to tweak timing, ease in/out of keyframes etc. If your object has its rotations animated as a quaternion you effectively lose this functionality, because the individual XYZW components of the 4D rotation don't correspond to anything intuitive in 3D space. So typically you want to keep your rotations in euler angles except in the special cases when you run into gimbal lock etc.

<comment><USER21> Okay, let's see if I have this right. The rotations are animated by manipulating the graphs of three functions of time, the values of which are the amounts of rotation around each coordinate axis?

The only rotation animations I've made have been done with code.

<comment><USER22> Pretty much. Usually you do the rough animation by manipulating the objects in the 3D viewport (with the manipulator using euler angles even in the cases where the angles are then converted to and stored as quaternions) and marking keyframes. The graph view is then useful for tweaking the interpolation between keyframes, minor adjustments, copying and pasting keyframes and such.

The graphs are time on X against rotation/translation/scale amount on Y, yes, with separate graphs for each axis.

</comment></comment></comment></comment></comment><comment><USER23> Ive been recently studying dual quaternions which are even crazier

[http://www.chinedufn.com/dual-quaternion-shader- explained/](http://www.chinedufn.com/dual-quaternion-shader-explained/)

They are THE formalism for representing translation and rotation since they interpolate super nicely.

<comment><USER24> You can just interpolate translation and orientation each individually (translation using linear interpolation, since it's an affine space, and orientation using SLERP or the matrix exponential and logarithm), and you should get the same thing as dual-quarternion interpolation.

<comment><USER23> Slerp is quaternionic interpolation.

<comment><USER24> It's not dual-quaternion anything, though.

(Also you can implement it with matrix logarithms and exponents, no unit quaternions necessarily needed)

<comment><USER23> Can you look into it first? Yes you can but dual quaternions are more suited for this.

<comment><USER24> I have looked into it, that's why I felt comfortable replying in the first place! ;)

Can you explain why dual quaternions are more suited and for what? I can understand the appeal of having "one number" to represent a rotation and translation. But the interpolation they provide is no different than if you interpolate the rotational and translational components independently, right?

By the way, the 2D analog of dual quaternions is dual complex numbers. They let you encode a translation and rotation (and scaling) in 2D, just as the dual quaternions do for 3D.

One thing that bothers me about dual quaternions, and you may have an answer to this, is that there's an 8th term that doesn't seem to buy you anything: the epsilon term (not multiplied by i, j, k). It's an 8-dimensional representation, whereas a quaternion + translation is a 7-dimensional representation.

For more information: [http://www.euclideanspace.com/maths/algebra/realNormedAlgebr...](http://www.euclideanspace.com/maths/algebra/realNormedAlgebra/other/dualComplex/)

[http://www.euclideanspace.com/maths/algebra/realNormedAlgebr...](http://www.euclideanspace.com/maths/algebra/realNormedAlgebra/other/dualQuaternion/index.htm)

<comment><USER23> The separation can be a problem if I want to for example do a Fourier transform.

<comment><USER24> A Fourier transform of what? If you have a reference, I'd love to learn more.

<comment><USER23> Hey can you email me? I'd like to continue this convo. My email is in my profile.

</comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER25> Where could one learn quartenion math?

For educational purposes, I want to generate a 3d rotating cube on the screen without any help from 3d kits like OpenGL and etc (I want to learn all the math there is to do this without any help, only rastering).

Thanks in advance.

<comment><USER19> You will need more than quaternions to get a rotating cube working without OpenGL. You would need some kind of basic lighting for this to work.

If you really want to build a 3d engine from scratch without OpenGL, I suggest checking this book out. It was written in the mid 90s and explains how to write a simple 3d engine in DOS.

[https://archive.org/details/BlackArt3DEBook](https://archive.org/details/BlackArt3DEBook)

<comment><USER19> Well, I suppose you could create a wireframed cube without any lighting...

But the above material is much more interesting.

</comment></comment></comment><comment><USER26> And if you take quaternions further, you end up with something you can generalize to any number of dimensions, which also unifies algebra and geometry in very nice ways: Clifford algebra.

[https://slehar.wordpress.com/2014/03/18/clifford-algebra- a-v...](https://slehar.wordpress.com/2014/03/18/clifford-algebra-a-visual- introduction/)

> Here we see the hierarchy of Clifford Algebras each with its own > characteristic pattern of components, that appear in numbers corresponding > to Pascal's triangle. Two-dimensional clifs, Cl2 (the even sub-algebra) are > mathematically isomorphic to complex numbers. Three-dimensional clifs, Cl3 > are isomorphic to Pauli matrices used to model subatomic particles. Cl4 is > isomorphic to Dirac matrices that model relativistic subatomic particles.

All of that assumes every element of the metric signature has the same sign; that is, the dot product of any basis vector with itself is always positive for all of them or negative for all of them. If you pick one dimension to have a sign opposite the others, that dimension is your time dimension and you're now in Minkowski space. The consequences of doing that is literally the entirety of Special Relativity.

If you construct a Clifford algebra in Minkowski space, that's Spacetime algebra:

[https://arxiv.org/abs/1411.5002](https://arxiv.org/abs/1411.5002)

> We present a comprehensive introduction to spacetime algebra that emphasizes > its practicality and power as a tool for the study of electromagnetism. We > carefully develop this natural (Clifford) algebra of the Minkowski spacetime > geometry, with a particular focus on its intrinsic (and often overlooked) > complex structure. Notably, the scalar imaginary that appears throughout the > electromagnetic theory properly corresponds to the unit 4-volume of > spacetime itself, and thus has physical meaning. The electric and magnetic > fields are combined into a single complex and frame-independent bivector > field, which generalizes the Riemann-Silberstein complex vector that has > recently resurfaced in studies of the single photon wavefunction. The > complex structure of spacetime also underpins the emergence of > electromagnetic waves, circular polarizations, the normal variables for > canonical quantization, the distinction between electric and magnetic > charge, complex spinor representations of Lorentz transformations, and the > dual (electric-magnetic field exchange) symmetry that produces helicity > conservation in vacuum fields. This latter symmetry manifests as an > arbitrary global phase of the complex field, motivating the use of a complex > vector potential, along with an associated transverse and gauge-invariant > bivector potential, as well as complex (bivector and scalar) Hertz > potentials. Our detailed treatment aims to encourage the use of spacetime > algebra as a readily available and mature extension to existing vector > calculus and tensor methods that can greatly simplify the analysis of > fundamentally relativistic objects like the electromagnetic field.

More prosaically, it allows you to write all of the Maxwell equations in a single equation.

[http://www.av8n.com/physics/clifford- intro.htm](http://www.av8n.com/physics/clifford-intro.htm)

</comment><comment><USER27> Seems like a wierd article trying to support octonions. I've graduated from quaternions using Lie Algebra/Groups (not that I understand them completely) but I find it much more general that it handles translations in a much better fashion.

</comment><comment><USER28> If you like quaternions, you should check out the split-quaternions. They're equivalent to the 2x2 matrices, but help you understand them better by using analogies to the highly familiar and intuitive quaternions.

</comment><comment><USER29> I get why Euler angles are not ideal (gimbal lock). But what are the advantages of quaternions over rotation matrices?

<comment><USER30> (From the point of view of graphics programming.)

The advantage/disadvantage of a 4x4 matrix (i.e. homogenous coordinates) is that you can describe the full transform--position, rotation, scale, and skew --in one go. If you only care about rotations, then using quaternions is less multiplication. Plus quaternions sidestep any issues with unwanted scale/skew if you're dealing with rigid-body objects.</comment></comment>


Containerd – a core container runtime project for the industry - <AUTHOR> https://blog.docker.com/2016/12/introducing-containerd/ <comment><USER2> Here is a follow up blog post with more details about containerd: [https://blog.docker.com/2016/12/containerd-core-runtime- comp...](https://blog.docker.com/2016/12/containerd-core-runtime-component/)</comment>


Ask HN: With emscripten, can C++ developers write web app without JavaScript - <AUTHOR> Today is it possible to build a reasonably complicated single page web application, currently requires AngularJs or ReactJs, using C++ only (together with css and html)? How can you do data binding between html and compiled javascript like in AngularJS? Is there any tools to support this?<p>Is this also one of the goals of WebAssembly? ie. to enable non-web developers to write web application in their own language. <comment><USER2> I think you can use (x)inetd.

It's a linux wrapper, it listens to port X and calls an application everytime it gets a new connection.

The application will receive the HTTP requests in stdin. You'll need a parsing library to parse the request and generate a valid answer.

It's really old and deprecated technology but it's rather simple.

</comment><comment><USER3> Why would you want to do this? It doesn't make it faster than JavaScript. You'd still need to interface with JavaScript Web API bindings, which means you'd need C++ bindings to JavaScript bindings, which... use C++...

You can _currently_ do this without WebAssembly, but there's zero point to it.

<comment><AUTHOR> ok, so the main usage of emscripten is to compile C++ to javascript and then call them from the "normal" frontend javascript code? ie. most UI related frontend job will still be coded in javascript?

As to the question why, C++ is not only about runtime performance, it's a more mature language than javascript/typescript and there are powerful data structure/design patterns/algorithms that are missing from javascript. Of course I see it this way because I'm way more competent in C++ than javascript.

<comment><USER3> I definitely appreciate that being a C and C++ developer, but you're sorely misled if you think that runtime carries over. Emscripten just translates the language to something usable through asm.js with a similar execution flow, but you end up running JavaScript. That's what it compiles to. Even WebAssembly is designed to run something that is consumed by the very same JavaScript runtime.

<comment><AUTHOR> Are you sure about WebAssembly? I thought it's a new byte code standard and a completely new runtime on its own.

<comment><USER3> Yeah, it's designed to pass through the same mechanisms that handle JavaScript. It's a new byte code standard afaik, too, but one that's used in those systems.</comment></comment></comment></comment></comment>


Helping publishers recover lost revenue from ad blocking - <AUTHOR> https://blog.google/topics/ads/helping-publishers-recover-lost-revenue-ad-blocking/ <comment><USER2> Nagware... great idea. Now i will just need a google blocker.

/s</comment>


Ask HN: Best Resources to Get Started on Control Groups/Containerization? - <AUTHOR> Recently have started to learn more about containerization and control groups/namespaces. I've found a few articles online, but most of them repeat similar examples e.g. spawning a process and then altering its control group using the shell.
Are there any good sources that would service as a good introduction to control groups/containerization? In particular ones that talk about the correct level of abstraction in a particular system. Ones which talk about production implementation examples would be great as well.
Thanks! <comment><USER2> Hi, sadly I don't have anything to point to. But this thing is interesting, you could compile one of those "awesome" lists on github :)</comment>


Show HN: gotests – Generate table driven tests in Go - <AUTHOR> https://github.com/cweill/gotests <comment><AUTHOR> Hey all,

I've been working on gotests for the past couple months outside of work. My team at Google works in Go, and has gotten a lot of utility out of this tool/plugin. It generates tests that follow Google's own Go style guide, so I thought I'd share it with the world.

It also has a plugin for EMacs and Sublime Text.

</comment><comment><USER2> This my personal go-to project for testing in Go, popular with the rest of my team as well. Even when I'm not using the plugin directly I read the test files themselves as a guide to "correct" testing syntax. Highly recommended.</comment>


Warren Buffett Will Give You $1 Billion For A Perfect March Madness Bracket - <AUTHOR> http://www.businessinsider.com/warren-buffett-billion-dollar-bracket-2014-1

<comment><USER2> why not generate all possible brackets and submit?

<comment><USER3> there are 9,223,372,036,854,775,808 possible brackets

</comment></comment><comment><USER4> Really? A scrape from a story on Yahoo.com?</comment>