Intertwingled: The Work and Influence of Ted Nelson – Starts at 9:30AM PDT - <AUTHOR> http://chapman.edu/events/intertwingled/index.aspx <comment><USER2> If it's not already going to be recorded, can someone here do that? I'll be in class when it's going on and won't be able to watch it. :(

<comment><AUTHOR> It will be available for a while.

</comment></comment><comment><USER3> I don't know if I necessarily approve of this, or entirely trust its accuracy, but this 1995 hatchet job on Ted Nelson is a great read: [http://archive.wired.com/wired/archive/3.06/xanadu.html](http://archive.wired.com/wired/archive/3.06/xanadu.html)

<comment><USER4> That is a very sad article indeed. I believe Ted Nelson's work is hampered a lot by the fact that none(?) of his texts are available as ebooks/reprints -- which mean they're far to difficult to get ones hands on in order to read the original.

The insights Nelson brings to the idea of hypertext (besides coming up with the term in the first place) are somewhat more significant than for instance Fielding's contributions in his REST paper (partly because Nelson was so far ahead of everyone else).

<comment><USER5> If you don't mind spending a couple hundred bucks you can pick them up used on Amazon. If you just get one, get Literary Machines.

It just covers the basic concepts though, not all the details of "enfilade theory" and so on. That stuff gets really complicated and I haven't found a clear explanation anywhere. Nelson kept it secret for a long time.

This article covers the basic concepts: [http://www.xanadu.com.au/ted/XUsurvey/xuDation.html](http://www.xanadu.com.au/ted/XUsurvey/xuDation.html)

And this briefly introduces their more complex ideas: [http://xanadu.com/tech/](http://xanadu.com/tech/)

I just found this page, which has some Internet Archive links that go into as much detail as I've seen: [http://fileformats.archiveteam.org/wiki/Enfilade](http://fileformats.archiveteam.org/wiki/Enfilade)

<comment><USER4> I certainly do mind spending several hundred dollars on some second-hand paperbacks -- when the things should just've been made available for reprint (and as ebooks). Not to mention that it pretty much rules them out as curriculum for any kind of course on hypermedia. That said, I do think they're great books.

<comment><AUTHOR> computer lib is now in reprint. [http://hyperland.com/LibPage](http://hyperland.com/LibPage)

<comment><USER4> Well that's nice. Not sure I'm entirely convinced they shouldn't be able to make it available cheaper than 100$/book (and as a pdf...) -- even just assuming they're able to print it at reasonable quality there should be _something_ available for making a high quality scan...

Still, great that it is available!

<comment><AUTHOR> it's a different form factor: [http://www.digibarn.com/history/grand- opening/images/amara-c...](http://www.digibarn.com/history/grand- opening/images/amara-computerlib.jpg) ... At small volume printing, you'll have to pay a good amount to get such a custom work done.

And Ted's is an idealist ... he would never be ok with a PDF version of the work. Those letters are fighting words.

Also in that shot you'll get a rare rare glimpse of Steve Inness without a hat!

</comment></comment></comment></comment></comment></comment></comment><comment><USER6> Only Silverlight or HLS supported :|

<comment><AUTHOR> I'll ask around about getting it officially put on YouTube

</comment></comment><comment><USER7> Link to the Open Xanadu demo:

[http://dl.dropboxusercontent.com/u/126637177/Phase_1_no_nav_...](http://dl.dropboxusercontent.com/u/126637177/Phase_1_no_nav_for_Ted/Xanaburger.html)

Doesn't work for me due to Javascript errors, but I figured I'd post it all the same.

<comment><AUTHOR> this was just out today. done by nicholas levin.

<comment><USER7> You wouldn't happen to have a link to a working version, by any chance? I'd like to play with it, and I'm not soon going to have the time to sort out what's wrong with the version I linked.

<comment><AUTHOR> nothing on the mailing list yet. If I don't see anything by Monday, I'll ask him.

</comment></comment></comment></comment><comment><USER5> Streaming video doesn't seem to be working. I'm on Windows 7, tried with Chrome and IE. I clicked the link for the presentation that should be running now but it just says "waiting for presentation to begin."

<comment><AUTHOR> Someone got it working on a Mac.

</comment></comment><comment><USER8> this is a Ted Nelon tribute event. so the title should name him first!

some lectures of his here [http://www.youtube.com/watch?v=KdnGPQaICjk](http://www.youtube.com/watch?v=KdnGPQaICjk)

</comment><comment><USER5> Some other big names at the conference too...Alan Kay, Jaron Lanier...if I'd known about this one in advance I'd have been tempted to take the day off work!

<comment><AUTHOR> Woz is here too. It's pretty epic for a room of 45 people

<comment><USER5> Wow. Ok I would have gone in person.

</comment></comment></comment><comment><USER9> Is anyone seeing the live broadcast? I am not, as of 9:44

<comment><AUTHOR> It started about 945 ... But I'm in the back of the room.

<comment><USER9> Thanks. Still waiting for the live broadcast online at 9:50

<comment><AUTHOR> :( I'll ask around when I get a chance. I _thought_ it was a stream but it doesn't explicitly claim so.

<comment><USER9> Got it streaming on the Mac now. Was not working on Win8, laughably.

<comment><AUTHOR> Live? Chapman guy is in front of me now and says it will be live later

<comment><USER7> It appears to be either live or live-ish. (On the other hand, according to the schedule, Jaron Lanier should've been the first speaker, and he doesn't appear to have been from the perspective of the stream. Did he speak and it wasn't broadcast, or what?)

<comment><AUTHOR> I see him two rows ahead but unless I'm missing something he didn't speak yet. It was the chancellor, Wendy Hall, and now Christine Borgman

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER8> how sad that this doesn't even the front page of HN. he's the inventor of hypertext.

I recently wrote to Mr. Nelson and he is still working on his grand dream.</comment>


Ask HN: Do startups hire 50+ year old programmers?(US) - <AUTHOR> <comment><USER2> Yes they do, as long as you keep up with the trends, one of the things that tends to happen is at a certain age, usually in the 30's many developers will decide to sunset. e.g they just stick with COBOL, Java, etc. It can be a good career choice, usually there is an apex where wages decline or stagnate for a 5-10 years and then they see their effective wage start to rise given that new personnel entering the field opt for other technologies and older peers leave the industry. Given that reality a good deal of older programmer choose to take that course.

I don't think that age discrimination is as bad in the industry as people think it is. I think rather sun-setting at some point becomes too much of a draw for most and you also have those that defect to management. I know in my start-up experiences when I was young we used to look up to the older developers that took the effort to stay relevant.

Personally, I would hire someone of any age if they are proficient and have passion to build something. I think there may be some organizations that may look at older developers and think well we can't get 80 hrs a week out of them, but I think they are the minority and I personally would not want to work for an organization that would expect 80hrs a week a standard course.

<comment><USER3> I always frown a little when my older (by a dozen years or so) co-workers get frustrated when moving to new tech, like git. :( Too often they'll bristle at the mere suggestion that they should keep the dedicating an hour or two of their spare time each week/month to reading and learning new things.

Its not hard, regardless of obligations outside of the office. You can't just sit back and rest on the stuff you learned 10 years ago...

<comment><USER4> Why should they do this in their spare time? If it is important to the business, shouldn't the employers provide time for their employees to learn new technologies?

<comment><USER5> This is one of those assertions that is simultaneously true and irrelevant. A developer who is comfortable in git is better than a developer who's only willing to use Clearcase. How they get to be one or the other doesn't play into the value calculation. "That's not fair" is one of the least compelling arguments in business.

But then, I strongly object to the notion that older developers are likely to push back on (say) git. More likely, given the developers over 40 that I have known, is that the developer is likely to think that choice of VCS is banal; older developers are less likely to fetishize git or hg, which is a productivity trap for developers who are passionate about their VCS.

<comment><USER6> Thomas, this is totally irrelevant, but would you consider yourself one of those "older" developers? I'm intimately familiar with your comments, but I have no idea how old you are.

<comment><USER5> I'm 35.

</comment></comment></comment></comment></comment></comment><comment><USER7> I care about quality output, pure and simple. Productivity in our technology stack is what I'm looking for in candidates. I've encountered basically two types of programmers who are 50+ (my guess on their age, based on resume dates).

Those who (still) possess that curiosity to learn and the drive to create. They may not be completely current with every late-breaking technology (show me anyone who _really_ does, for that matter), but they embrace change and strive for improvement. They are the ones that make you forget about age -- young, old or somewhere in between.

And then there are those who seem like they walked in with their high-school letterman's jacket on, hanging on something they did years and years ago -- and having trouble transitioning to today's world.

While many people associate those 50 and older as "seniors", not everyone maintains senior-level status in this business. As we all age, we would do well to remember to rely on our natural instincts for curiosity and learning to keep the fires stoked and remain relevant in an industry that will continue to change for years to come.

<comment><USER8> I hope you remember there age, or more specifically what comes with _serious_ experience, when they e.g. look at the symptoms of a bug and say "It's going to be there" (in the code) and are right more often than not. That's something I achieved in C/C++, but only after, say, a decade and a half of working with them. (And this does translate to newer stuff where no one can have that much experience, although of course not as well).

Or take architecture. I know I've done a good job there when mine solves problems I didn't consciously anticipate. Again, that took nearly 2 decades from when I first started programming including a lot of reading on good software design, starting in that first year of programming ('77-8) and _never_ stopping. Heck, the older you are, the more time you've had to read and grok the classics.

Hmmm, to finish with a riff on some other observations in this discussion, the normal, _average_ outcome of a startup is failure. Perhaps one should consider non-normal approaches to staffing, like recruiting one or more grey-beards of the right sort who can save you days, weeks, even man-months of effort on individual things because of their experience. To paraphrase Scott Adams, sometimes you have the option of working harder or smarter. The latter frequently wins.

</comment></comment><comment><USER9> Youth is not a skill. I don't hire green college grads. And I look at anyone with less than 10 years of experience with suspicion. Knowing Ruby or Scala or whatever syntax is fine, but it's far less important than the underlying skills: OO design, distributed systems, threading... Specific languages and frameworks come and go. Many of the twenty somethings don't really understand that.

As for working 80 hour weeks, you're fooling yourself if you think people of any age can do that productively for an extended period of time. Plenty of research exists on that topic.

The key to hiring is to hire only A players who will be highly productive and produce quality code. In my experience A players are not twenty somethings. Do you think Delta Force recruits green beans fresh out of boot camp? Absolutely not. They recruit from the Rangers and Special Forces. Of course we can't all hire A players. But I can.

<comment><USER8> Actually, I like hiring one or so nearly green college grads of the right sort, who are willing to be mentored. As long as they are self-directed, can start working given basic directions and then ask you the right questions (my favorite example from a guy who'd only done C++: "where is new in C?" "ah, in C we malloc...."), they can be very productive and follow your vision. And as they learn, help to refine it.

I believe in trying to balance your team. A very few green apprentices (too many take too much time), enough seriously experienced masters (you're not likely to get many) and then journeymen in the middle, all of these aspiring to reach higher levels.

</comment></comment><comment><USER10> Here is an honest answer that you won't hear from many others. Startups are not the best option for 50 year olds.

Most 50 year olds demand high salaries, aren't willing to work long hours (let alone nights and weekends), are far less familiar with new technologies and less willing to learn, and are much more cynical than 20 somethings. The risk, uncertainty, and low structure environment of a startup is just a bad fit for the age group in general.

Our society hasn't yet adapted to the fact that as people get older in technology, they get less competent but demand higher and higher salaries due to their increasing fixed costs (mortgage, etc.).

Those who will argue with you about the above facts want to eat their cake and keep it too, like the women who want to have kids and pregnancy and a social life but also want to make it big at a high tech startup. People do not want to acknowledge that tradeoffs exist: that women with young children can't put in long hours or that old folks just aren't as plastic and supple.

Some engineers age like Ken Ritchie, and stay sharp. Some go into management or do consulting on legacy systems. Those are all legit options. A 50 something should have enough savings to bankroll his own startup; that too is a legit option. But working at a YC-style startup is not likely to be a good fit.

<comment><USER5> Our society hasn't adapted to the fact that people get less competent and unjustifiably more expensive with age because it isn't true.

People who get less competent get less competent; people who demand unjustifiable compensation demand unjustifiable compensation. Some of those people are 50+. Some of them are 25. Some 20-somethings code for 2 years, write an O'Reilly book, and then reposition themselves as "architects". So many young people did this with the title "CTO" that the term "CTO" got tainted.

This is something I was taught in 3rd grade, but apparently hasn't percolated into the public school system, so we're having to teach it to adults at great expense: _one needs to be vigilant about prejudice_.

Or, in some cases not, because one of the subtexts behind ageism is that talent is getting more and more expensive, and firms want to avoid engaging with that reality. At least 21 year olds come bundled with the pretense of inexperience, so you can pay them 40% of scale.

If I sound self-righteous about this, I apologize; I'm really not upset by it, because it is one of the more easily exploitable market inefficiencies our industry cultivates. You guys pay for the "Rails programmer" who foreaches through N+1 queries because they don't grok SQL joins; I'll pick up the 50 year olds who've shipped Lisp and written RISC assembly.

</comment></comment><comment><USER11> How much do families fit in the with culture of startup? Would it be odd for an employee to have to leave in the middle of the day to pick up sick kids at school? Will you be a "good fit" if sometimes your family responsibilities trump work. What is your desire and inner motivation at 50? It's probably a lot different than the 20yr and 30yr old startup culture. I would say if you are 50 yr old that fits in with the younger culture and have the necessary skills you will do just fine. The reality is though that you are probably at a much different place than the majority of startup employees. You have probably see enough to know how to best spend your time and your priorities are likely different than your peers. The guy doing the hiring knows all of this and where he won't directly use age as a factor in hiring he will take these other factors into consideration. good luck.

<comment><USER12> If you are 50 years old, your kids are likely to be old enough to get to home by themselves.

Personally I'd hate to work in a place where it would be considered odd to take care of some private business during the day every once in a while. Stretching and leeway goes both ways.

<comment><USER13> That's not as true any more. I know a number of couples that "started late" and will be in their fifties just as their kids enter the ~10+ year old age range where after-school activities ramp up yet the kid can't drive. People having kids later is probably going to be another of those slow social changes we'll all have to adjust to.

</comment></comment></comment><comment><USER14> Sure, but here are some prejudices people will have about you going into an interview:

\- You don't want to work enough (~80hr/weeks).

\- You aren't familiar with new technologies or languages, and aren't curious enough to learn.

\- You think slow, and don't have the ability to push stuff out the door quickly.

\- You want a senior position as an "architect" or "senior engineer" instead of being an IC like everyone else.

\- You want a bigger salary than everyone else.

\- It's going to be hard for people to relate to you and communicate with you.

If you can fight against all of those, go for it.

</comment><comment><USER15> kls doesn't think age discrimination is as bad as it is. I'll wager he doesn't think gender discrimination is as bad as it is either. He's more likely to age than he is to change gender, so we'll check back with him in 30 years.

It's kind of amusing to hear him think of COBOL and Java in the same breath; I've worked extensively with both. Not at the same time, though. :-)

He is on target in saying keeping your skillset fresh is key. Like the Red Queen, it takes all the running you can do to stay in the same place.

<comment><USER2> I'm old. I have almost 20 years in the industry.

</comment></comment><comment><USER16> Yes. I hire excellent people who are interested and interesting that fit into the culture of our company. Age/sex/race/gender/etc. are irrelevant.

</comment><comment><USER5> We did. Age wasn't a factor in the discussion. If you can play, we want you in the game.

</comment><comment><USER17> Speaking as a founder, yes I would. I'd also fire one just as quick.

I'm of the mindset that both employers and employees need to be flexible with one another. I may need you to pick up technologies you're not comfortable with and you may need spend your early evenings with your family. I may need you to work 60+ hours on a given week and you may need to work some of that on off hours.

It's a give and take situation with any startup employment. What's objective is what can you deliver and can I obtain a positive ROI from hiring you?

</comment><comment><USER18> I don't work for a startup but just wanted to comment since I work with a lot of older developers, one who must be well into his sixties is rather interesting as, while he does have his spots where he seems a bit stuck in the past, is constantly trying to inject new technologies into the organization. We're a primarily java shop and he writes a lot of scripts in Ruby and always wants to bring more ruby into projects. I also know he has probably more of a passion for developing software (personal projects) than some of the other developers, who are younger (but still much older than me). I think its really just based on the person. If they really love building software they will keep up at any age because they see the benefit in their own projects.

</comment><comment><USER19> Age does not matter. Skills matter. This is interesting. Have to lookup whether startups have already hired 50 plus year old guys? Maybe phd professors!

<comment><USER20> Age would matter for a startup beyond just skills. Older hackers might not be able to "keep up" and "fit in" with many startups. Culture fit is really important, but being old doesn't automatically mean no fit.

One interesting thing about a hacker being 50 is that they potentially have an empty nest (no kids), much like their 20s. In some cases they might be able to work "startup hours".

</comment></comment><comment><USER21> Companies in general rarely hire older employees exclusively for their technical ability.

The typical 50 year old programmer has worked at numerous organizations, with dozens of teams, using at least as many technologies. This directly contributes to the development of non-technical skills such as communication skills, management skills, insight, and stronger perception. They're rarely oblivious to these skills (as demonstrated by the relatively low numbers of older professionals selling themselves as "programmers").

<comment><USER18> I find this not necessarily true at my company, in fact the oldest people in the engineering department are exclusively developers where the managers tend to be younger or the same age as them. This may depend on region, as well, the area I live in now is rather different than Silicon Valley where I think people wouldn't stick around for years and years as "just a programmer" but in lower-cost, slower-pace areas, I think programming is often just another job to people and its something that people will just continue to do for their entire career.

</comment></comment><comment><USER22> When I've hired people, while working as an engineering lead at a startup, It's never been about age, it's been about skills + personality. Out of a development team of around 10 people, I'd say 2 were >= 50 years old, a few 30 somethings and the rest around 20-25.

</comment><comment><USER23> some? yes

most? You won't get hired, because you'll be seen as a bad cultural fit for the company.

Only real way to get in as someone that old, is if you are going for the position of a CTO

<comment><USER5> I wonder how many of the people on this thread who share this opinion have started successful companies.</comment></comment>


Wiped-Out Hedge Fund Manager Confessed His Losses on YouTube - <AUTHOR> https://www.bloomberg.com/news/articles/2018-11-19/hedge-fund-s-accounts-liquidated-amid-energy-market-volatility <comment><USER2> Such is the life of an option seller, especially naked option sellers. You are picking up the proverbial nickle in front of the steam roller.

The really unfortunate part of this is that some of his clients actually owe more money than what was in their account.

There is a scummy way of managing money that some CTA's use where you don't get the proper license to manage others money as a hedge fund and instead just have people put money into accounts and then they give you the right to trade. Due to the use of leverage when the market moved against their naked short Nat Gas positions all the collateral posted in the accounts were not enough to covert the losses so some people are not only out the amount they wagered, but more.

And the worst part of it is the manager blaming this on an unforeseen event. Everyone who sells options knows that rule one is never be naked when you are short as your losses can be unbounded.

The reason for this is that if you have traded for even a short period of time you realized that while the market is liquid most of hte time, there are times when its not and the only thing you can do is watch it move while realizing you can't exit a position.

This happend to short sellers of KBIO when they thought they were riding a shitty stock to zero, when Martin Shkreli bought it for a premium causing margin calls for everyone short it.

See:

[https://www.investopedia.com/articles/investing/112315/did-m...](https://www.investopedia.com/articles/investing/112315/did- martin-shkreli-intentionally-burn-kalobios-shorts.asp)

As a side note Martin has a blog. [http://martinshkreli.com/](http://martinshkreli.com/)

its actually pretty good as this is what he does for a living and when hes out of prison he's going to try and go back to it so this is really the only way he can redeem his brand. I expect him to put everything he has into the blog. its' a good source of trading ideas.

TL/DR

\- never sell options

\- if you do then never sell naked options

\- if you do make sure you can get out of your trade

\- if you can't get out of your trade make sure you are well capitalized for loss absorption

\- if don't have enough to cover your losses don't apologize for losing your clients money while wearing a $10,000 watch and post it for the rest of the world to see.

<comment><USER3> Why would his clients owe money? The fund is the one doing the trading, so it's the fund that would owe money.

<comment><USER4> They were setup as managed accounts. Clients actually own the assets and in turn the liabilities.

<comment><USER3> Got it. Seems weird anyone would sign up for something like that.

<comment><USER5> I'm sure it was "cheaper" or they were friends/acquaintances and he just said "I can make you money" - because he wasn't a "real" (eg with the presumably expensive accounts and control systems) it was probably easiest to have it set up that way.

Question for people who understand things better than me: isn't setting up an LLC in America quite cheap? Couldn't an individual make an LLC to hold their investment funds, and then give him control of those accounts? Wouldn't the LLC protect them? (Not saying that such a layer is free, but it seems like a relatively cheap protection)

<comment><USER4> Without getting into specifics, some investors prefer separately managed accounts. It has nothing to do with difficulty of setting things up and everything to do with preference. That said, if for some reason I wanted to invest in something that sold naked options, I would prefer to invest with an LLC.

<comment><USER6> Aren't managed accounts orthogonal to liability? e.g. if I wanted to invest my money in a managed account, I could _still_ set up (my own) LLC to limit liability (and that could be better even for e.g. tax reasons).

<comment><USER7> What prevents people from setting up such LLCs and go nuts on such naked options? I mean you can bankrupt the company if they go wrong, reap it if it works out. I am sure I am missing some gaping hole there.

<comment><USER6> Yeah, options are either traded on an exchange, in which case the exchange should ensure that its members/participants have enough capital to cover the trades, and that makes the exchange itself liable (i.e. the exchange is the counterparty) - see e.g. the recent case of an energy trader going belly up in Norway [1] - he wiped out the whole emergency fund set up by the exchange itself, as well as a huge chunk of the secondary emergency fund set up by the exchange members. Otherwise, you're trading options OTC i.e. directly with another counterparty (e.g. an investment bank, private trader, etc), in which case the other party bears "counterparty risk" (i.e. the proximal cause of the last financial crisis - "will the bank that I've $100bn of exposure to still exist tomorrow or not") which they should manage and/or enforce in court if necessary (i.e. options are just contracts).

TL;DR: the person on the other side of the transaction needs to be reasonably sure you can hold your end of the deal.

[1] [https://www.forbes.com/sites/heatherfarmbrough/2018/09/14/no...](https://www.forbes.com/sites/heatherfarmbrough/2018/09/14/norwegian- energy-market-trader-creates-e114m-hole-in-nasdaq-clearing-fund/#621f8746ce57)

</comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER8> I can't believe he'd say, "I owe you a cuban sandwich" to someone whose life- savings he presumably gambled away on options. I seriously thought this was the Onion when I heard that.

[https://www.youtube.com/watch?v=VNYNMM0hXXY&feature=youtu.be...](https://www.youtube.com/watch?v=VNYNMM0hXXY&feature=youtu.be&t=128)

<comment><USER9> > _someone whose life-savings he presumably gambled away on options_

It's a stupid line. But nobody with any sense has more than 5% of their portfolio in a single hedge fund.

<comment><USER5> The problem is that even if they had only 5% in that fund, the way it was managed meant that they ended up owing more than was originally put in. Options (or at least naked? Ones) have unbounded loss. You can end up owing vastly more than you started off with.

<comment><USER10> Only if you sell. Option buyers have a loss floor built-in.

<comment><USER5> My understanding of options was essentially that you borrow N shares of stock X with a promise to buy it back. You then sell your shares to get so many $$$ (much wow, such bankruptcy ;) ). Then later when the stock goes down you buy back N shares and pocket the difference, and use those N shares to pay back your loaned shares.

The problem seems to come from selling your shares and then the stock unexpectedly (to you at least) rising so that buying back N shares costs you more money than you necessarily have.

As far as I can make out the way people make "huge amounts" from options is going down that path.

Are you saying that another common approach is to buy your options and instead bank on the value of the options themselves increasing?

This is a legit non-sarcastic question as it literally never occurred to me to do this :)

<comment><USER10> What you are describing is short-selling. An option is a contract to buy (or sell, depending on the option) 100 shares of some stock at a set price, which expires at the end of a set day (usually the 3rd Friday). This contract costs some premium, which is lost if the option expires before the owner exercises it.

You can indeed make a lot of money just holding the option until it is worth more, and it can jump several multiples of the original price, especially on unexpected price movements.

As the option cannot have a negative price, your losses are capped at whatever you spent on them.

</comment></comment></comment></comment></comment></comment><comment><USER11> I find this difficult to watch.

The only thing that would make this less difficult for me to watch is if he had his personal fortune invested in his hedge fund also, and so was similarly wiped out. In which case I'd like to hear it.

Otherwise if I was an investor I couldn't help but think: "sure, but you only lose our 2 and 20 this year, what happened to the 2 and 20 you made through the last few decades?".

It would actually be an interesting law:

"Operators of investments must have a higher fraction of their wealth invested in the fund than any of their investors".

Obviously difficult to implement but the spirit of it is fascinating to me. That way, when a hedge fund fails, the entity which has been the most ruined by it (fractionally speaking) is the CEO. It'd create genuine skin in the game.

<comment><USER12> That's the idea behind Nicholas Nassim Taleb's most recent book "skin in the game". People should be exposed to the downside risks of their actions.

<comment><USER11> Yeah, I was 100% cribbing off Taleb's broad point, which I'm familiar with. Do you know if he's suggested this particular idea, or something similar?

</comment></comment></comment><comment><USER13> The photo at the top of the article reminded me of a sight in northern New York, and apparently being duplicated in many parts of the country: Tens of thousands of obsolete and unneeded tanker cars sitting idle on rural sidings and unused lines:

[https://www.npr.org/2015/09/14/440173575/what-to-do-with- rai...](https://www.npr.org/2015/09/14/440173575/what-to-do-with-railroad- tank-cars-that-are-no-longer-safe-or-economical)

The collection I saw last year next to Route 12 in New York was at least 10 miles long, and there is another one in the Adirondacks. It's an eyesore to say the least ... possibly a pending environmental hazard. If there's a declining need for oil to be transported around the country on trains, and the cars are expensive to recycle or transform, what will happen to them?

<comment><USER14> Likely the same thing that happened to all the mills throughout the rust belt. They'll get abandoned. The pessimist in me says that they'll get sold to a new corporate entity which will then file for bankruptcy and the government at some level will need to clean it up.

</comment></comment><comment><USER15> It appears that this fund was mostly in the business of selling options. Nassim Taleb often warns this is a dumb idea because in the long run something bad will happen from which you can't recover. I tend to agree and while it's sad for those involved I believe they can only blame themselves. They haven't been prudent.

<comment><USER16> Options are extremely high risk and should be avoided. Naked options are an excellent way to part a fool and his money. Investing in anything that potentially exposes you to unlimited losses is eventually going to expose you to unlimited losses and you can't make that up with volume.

</comment></comment><comment><USER17> A good thought experiment is to imagine a hedge fund which invests in the s&p500 all the time, but once per year takes all its capital and sells options with a 5% return and a roughly 1/20 risk of ruin. On average they beat the s&p500 by 5% every year, and only explode once every 20 years on average.

If you could charge 2 and 20 and smoothtalk investors the chances that you get rich before it explodes are pretty good.

Differentiating an investment with a negligible chance of going to zero (like the s&p500) from one with a small but nonzero chance is difficult until one of them explodes.

</comment><comment><USER18> This is bad, but $150M lost in the natural gas market is not the worst I've seen. There was Brian Hunter of Amaranth [1] fame that blew up a $9B hedge fund with a bad NG trade. Amaranth had to liquidate assets for pennies on the dollar to cover the margin calls. Wikipedia is note entirely correct, here, though. It says that JP Morgan & Citadel bought the assets, but it was Citadel that bought them all at the end of the day. My understanding at the time was that JPM couldn't calculate in time the risk involved with the assets they were planning on buying.

[1] [https://en.wikipedia.org/wiki/Brian_Hunter_(trader)](https://en.wikipedia.org/wiki/Brian_Hunter_\(trader\))

<comment><USER4> Centaurus/John Arnold was another party here. While they were not part of the liquidation they had ridiculous returns that year as a result of the Amaranth situation. The book Hedge Hogs is a good read on Amaranth.

Dollar amount aside, I'd argue this is worse in some ways because it dealt with individual investors who are now figuring out how to fund margin calls.

</comment></comment><comment><USER19> I'm sorry for the destruction of wealth on one side, but the traders on the other side made a killing.

What happened here is fat tail risk that is always present in the market.

</comment><comment><USER20> Seems like a non-apology. It was all the "rogue wave" that "capsized the boat."

If a fund can't manage volatility surges, the blame isn't the rogue wave that, out of nowhere blew everything to smithereens, but the guy who steered right into it.

It's the difference between being sorry that the house you destroyed with a car was in your path vs. being sorry for having left the party drunk.

<comment><USER16> I mean, nobody can manage volatility 100% of the time when they are selling naked options.

</comment></comment><comment><USER21> I have no experience investing in hedge funds, but I feel like having a name like "OptionSellers.com" might be a red flag?

<comment><USER16> Why? That's literally what he does.

</comment></comment><comment><USER22> Extending this man a hug in this professionally devastating time and hoping his inner circle makes sure he stays afloat himself.

<comment><USER4> This guy deserves no sympathy. He gambled his client's money in an extremely irresponsible manner.

<comment><USER6> How do you know he "gambled in an extremely irresponsible manner"? Was he misrepresenting the risks he was taking in some way? The domain "optionsellers.com" suggests he was rather transparent...

<comment><USER4> This person claims that they were an investor and put together a spreadsheet with several days of NG trades. What I see is someone being irresponsible.

[https://twitter.com/waklyn1/status/1064307589578579968](https://twitter.com/waklyn1/status/1064307589578579968)

<comment><USER16> That looks like a well-informed investor understanding _full-well_ that they were buying naked options and the enormous risks associated with that.

<comment><USER4> They were selling options; not buying them. Hard to blow up like that if you're buying options. Regardless of what the investor did or did not understand, my point stands; this guy was extremely reckless.

<comment><USER16> Whoops, that was an error rather than misunderstanding. Anybody selling naked options is playing an enormously dangerous game. Any investor throwing money at a game like this knows the risks, or they wouldn't even know the firm exists.

<comment><USER4> Like I said above, only talking about dude in charge.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER23> I think now would be a great time to open a new account. What could go wrong? [https://www.optionsellers.com/accounts/](https://www.optionsellers.com/accounts/)

</comment><comment><USER24> Tragic. From the video, I half expected him to put a gun in his mouth at the end of it.

What happens now for this guy? He mentions it likely wiped out his firm. Likely? How can anyone who has done this have any chance to remain in business, and feel secure enough not to even go into hiding? If the losses are unbounded, can a number of his clients be totally wiped out, even if they were diversified?

He'll continue to wear a watch worth more than my car, and have a suit worth more than all my clothes combined. I have a hard time imagining his lifestyle will even suffer.

<comment><USER25> You sound envious.

<comment><USER24> ... his entire reputation is ruined. How does somebody come back from this? I like sleeping with both eyes closed at night, don't you?

</comment></comment></comment><comment><USER26> This man has no right handling other peoples' money. This is sheer incompetence.

</comment><comment><USER27> Is there blood in the streets yet?</comment>


Ask HN: Does Gitlab's website always feel slow to you too? - <AUTHOR> <comment><USER2> Yes. I try to open issues and reply to comments by email with templates. I do the most I can through command line, but I have to look at hundreds of issues and many merge requests, prioritize them, review, etc, augment and edit issues and comments. I have to interact somehow with the site although I try to minimize that interaction.

But I don't know anyone who likes the interaction. Even non technical staff were delighted when I told them they can create issues with email, and are learning command line not to interact with the site (just pull, and look at documents, change commit, push).

It still solves a problem, though, and I'm grateful. GitLab is really cool and it is a company, and a product I respect a lot.

</comment><comment><USER3> Yes, it happens to me also. Sometimes is just frustrating. :/

</comment><comment><USER4> Nope</comment>


Recreating the THX Deep Note (2009) - citywide-fondue http://earslap.com/article/recreating-the-thx-deep-note.html <comment><AUTHOR> Here's what the THX note would look like in creative sheet music notation. [https://twitter.com/THX/status/1000077588415447040](https://twitter.com/THX/status/1000077588415447040)

DEEPNOTE from NYSTHI for VCV Rack does this in a virtual modular environment. [https://github.com/nysthi/nysthi#deepnote](https://github.com/nysthi/nysthi#deepnote) You could create this with other modules too, like E-Series E340.

</comment><comment><USER2> There's seems to be a THX contest on currently and I found this version quite remarkable. [https://youtu.be/ZRvJW4-izLs](https://youtu.be/ZRvJW4-izLs)

<comment><USER3> that is amazing haha

</comment></comment><comment><USER4> That's really neat.

There is a very good 20 000 Hz podcast on the creation of the THX Deepnote:

[https://www.20k.org/episodes/thxdeepnote](https://www.20k.org/episodes/thxdeepnote)

[https://www.20k.org/episodes/thxdeepnote2](https://www.20k.org/episodes/thxdeepnote2)

</comment><comment><USER5> If you're interested in the history of stuff like this be sure to look into Beaver and Krause ([https://en.m.wikipedia.org/wiki/Beaver_%26_Krause](https://en.m.wikipedia.org/wiki/Beaver_%26_Krause)). If you recognize the THX sound then you'll also probably recognize the last 30 seconds of Spaced ([https://youtu.be/2xKO3KAtDZ0](https://youtu.be/2xKO3KAtDZ0)). They started off as early Moog salesmen showing off equipment and ended up introducing many famous musicians like George Harrison, the Doors, and the Byrds to electronic music. They also scored for movies such as The Graduate, In Cold Blood, Point Blank and Rosemary's Baby. True pioneers in the space and good music to boot.

</comment><comment><USER6> The version on the official site (worth a few clicks if you have headphones)

[https://www.thx.com/deepnote/](https://www.thx.com/deepnote/)

<comment> another-cuppa Headphone? Deep Note was made for speakers.

<comment><USER7> And mixed for at least a 5.1 soundfield. The low frequency start absolutely has to come from the subwoofer, or the whole effect is lost.

I have deepnote as an AC3 audio file, along with a lot of other sound clips such as the original Dolby Digital trailers (the steam train is my favourite), and when ever I'm tweaking the audio in my Home Cinema I always fire them all up and give the house a good shake :)

<comment> another-cuppa It doesn't necessarily have to come from a subwoofer. Dolby specifically states that the LFO channel does not have to correspond to a physical speaker. The LFO channel only exists to ease retrofitting a subwoofer into old cinemas (in that case they would simply wire the LFO to a subwoofer and be done). But any other channel can contain bass information and in practice a new cinema will use a bass management system to route bass from all channels into their subwoofers. In theory a cinema could also have no subwoofers at all and send all bass to the mains and drop the LFO. It all works.

</comment></comment></comment></comment><comment> basil-rash Link to the real one seems to be dead. Here's a version I found on youtube: [https://www.youtube.com/watch?v=uYMpMcmpfkI](https://www.youtube.com/watch?v=uYMpMcmpfkI)

<comment> basil-rash Edit: someone else posted a much better version, [https://www.thx.com/deepnote/](https://www.thx.com/deepnote/). My link fails in comparison. Also, that website is actually pretty cool.

</comment></comment><comment><USER8> Prior discussions:

2014: [https://news.ycombinator.com/item?id=7537674](https://news.ycombinator.com/item?id=7537674)

2009: [https://news.ycombinator.com/item?id=725564](https://news.ycombinator.com/item?id=725564)

</comment><comment><USER9> This has been on HN several times in the past:

[https://hn.algolia.com/?query=Recreating%20the%20THX%20Deep%...](https://hn.algolia.com/?query=Recreating%20the%20THX%20Deep%20Note&sort=byDate&dateRange=all&type=story&storyText=false&prefix&page=0)

</comment><comment><USER10> Maybe someone here can help.

A few years ago I tried to implement what is shown on that page but without using something like SC, i.e. I was generating list of samples directly. I recall I was stuck trying to find how the 2nd order resonant Low Pass Filter (BLowPass [1]) was working.

Any good pointer to help me write it would be appreciated. I didn't spent much time reading SC source but I think it was not very clear for me without much sound synthesis knowledge.

1\. [http://doc.sccode.org/Classes/BLowPass.html](http://doc.sccode.org/Classes/BLowPass.html)

<comment><USER11> A typical implementation is simple - a couple of single sample delays, a couple of multiplications, some addition.

Deriving the coefficients and the design is not simple. There is math.

[https://ccrma.stanford.edu/~jos/filters/Two_Pole.html](https://ccrma.stanford.edu/~jos/filters/Two_Pole.html)

A characteristic equation called the Transfer Function defines what a filter (actually any circuit) does using polar complex numbers to represent the frequency and phase of an arbitrary input signal.

Basically the TF says "If you put a sine wave in, the circuit will change its amplitude and phase like this" \- across all possible frequencies.

Filters are usually designed with a combination of poles and zeroes.

Poles are low-pass building blocks. Zeroes are high-pass building blocks.

Poles are a polynomial on the denominator of the Transfer Function, zeroes a polynomial on the numerator.

When you have your continuous Transfer Function you apply something called a z-transform, which gives you a form you can turn into a difference equation, which is basically the core equation for the filter, and another set of equations for calculating the coefficients.

Instead of deriving this from scratch you use standard forms which you can find on sites like the JOS tutorial I linked to, and dspguru.com.

But you do need to have some idea how all of this works - and also when this nice simple model stops working. (E.g. digital filters have issues close to the sampling rate, so good designs compensate for this and don't just use the difference equation blindly.)

<comment><USER10> Thanks a lot. It seems this remains quite a challenge to turn those into working code though !

</comment></comment></comment><comment><USER12> Here is one done in Pd:

[https://www.youtube.com/watch?v=Rz1uNLHorEs](https://www.youtube.com/watch?v=Rz1uNLHorEs)

The little GUI allows you to change all the parameters, like the partials of the final chord and the range of the glissando for each voice.

But I think the sound would only "lock in" by recording an actual cello and using that for the source of the oscillator. (A friend of mine suggested a cello harmonic which seems right given the timbre of the opening texture.)

<comment><USER12> There's also the issue of how far each voice travels from its initial randomly chosen state to its goal frequency.

It sure sounds to me like the original algorithm sought to choose initial frequencies that would be farthest from the goal frequencies. In other words, a lot of voices traveling several octaves from low to high while others go low to high. But I haven't tested that.

</comment></comment><comment><USER13> The one at the end that fits in the size of a tweet sounds better than all of them, IMO. Including the original.

</comment><comment><USER14> The early part (with the most randomness) sounds very similar to the prop buzzing noise multirotors make.

</comment><comment><USER15> I would never have thought there is a C code behind this masterpiece.</comment>


Ask HN: Are there any NLP projects that use context? - <AUTHOR>

I was thinking about natural language processing today. I am by no means educated on the subject, but it seems like an interesting field. Most NLP libraries can parse text into its parts-of-speech, but often times it can be wrong because it's a word like "project" where the verb form is a completely different word than the noun form, etc.
In all the libaries I looked at, "project" was interpreted as a noun despite the sentence being "We will project our earnings".
Could we not provide context to the parsing process? For instance: a database could store the frequency of parts of speech for a given word's N nearest neighbours (ie. the n-1 neighbour of "project" is a definite article 90% of the time), as well as the frequency for each part-of-speech for the given word. So if the n-1 neighbouring word of "project" was not a definite article, it may indicate with a certain weight that "project" is not being used in its typical form either. Then you could do the reverse lookup (the n+1 neighbour of "will") and see that that neighbour is a verb 50% of the time. Putting those two pieces of information together gives you pretty good confidence that "project" probably isn't a noun like it usually is.
So is this just too computationally expensive or is there something else that I'm missing? <comment><USER2> There are a lot of ways of creating context in NLP. When a normal person thinks of contex, they probably consider the meaning of the sentence and from there they'll figure out the POS.

For a simple POS-tagger you would today probably use an HMM. What this means in simple terms in you look at how likely is the next word (regardless of what word there may be) to be a given category. Let's say the next word has a 50/50 chance of being a verb or a noun. Then we look at the actual word "project" which has a 20/80 chance of being a verb or a noun.

In another context the POS might have a 90% chance of being a verb, and then project would probably end up being. Tagged as such.

You can also start looking at bi, and trigrams (series of two or three words) and so on.

So what you describe is pretty much an actual thing.

<comment><AUTHOR> Oh interesting! Thanks for sharing.

</comment></comment><comment><USER3> Yes, some NLP POS (part of speech) taggers do use context. I'm not entirely sure if they work in the way that you describe. I believe that they use the grammar of the sentence to derive what the tags over the sentence are. That is, they can tag the sentence on what they know and then iterate over the sentence until everything can fit into the grammar (or corpus) that it was trained on.

If you want more background - the nltk book, in particular chapter five is a good place to start: [http://www.nltk.org/book/ch05.html](http://www.nltk.org/book/ch05.html)

What library did you use? NLTK on Python 2.7 gave the following:

[('We', 'PRP'), ('will', 'MD'), ('project', 'VB'), ('our', 'PRP$'), ('earnings', 'NNS')]

<comment><AUTHOR> Interesting I'll have to take a look at this Python lib. I was trying out various Node.JS libs.</comment></comment>


Show HN: UIChamp, a fun way for designers to compete and learn - <AUTHOR> http://uichamp.com/

<comment><AUTHOR> My teammate Dane brought up this idea over lunch, and we hacked this out last night. We thought it would be really interesting if designers could submit their best 'signup' button and compete to see which one is most clickable. There are a lot of interesting places to go from here: design categories, vote tallying methods, and analysis of user demographics and their design preferences. We're both longtime readers of HN, and we'd love to get feedback from the community.</comment>


Behind the music: What if the culture industry shut down for a day? - <AUTHOR> http://www.guardian.co.uk/music/musicblog/2012/jan/19/behind-music-anti-piracy-legislation

<comment> wh-uws I'll say here, what I said to a friend who sent me this:

I say music industry folks should get together and do it.

Let me tell you why. On our in end and for our part us in the tech industry we're like its just the MPAA, the RIAA, and the militant people who are crazy rich already and just want the government to protect their outdated business models.

To us piracy is a service problem. [http://www.escapistmagazine.com/news/view/114391-Valves- Gabe...](http://www.escapistmagazine.com/news/view/114391-Valves-Gabe-Newell- Says-Piracy-Is-a-Service-Problem)

[http://www.tcs.cam.ac.uk/story_type/site_trail_story/intervi...](http://www.tcs.cam.ac.uk/story_type/site_trail_story/interview- gabe-newell/)

The old way of distributing this stuff is over. And only the people who are versed in the newer ways (i.e. blowing up on Youtube and then doing shows) are going to make it. And the record labels can't control that and that is what scares them. Becoming obsolete

If regular people in the music industry were to strike to bring attention to the issue, we would take it more seriously. It would go from "a bunch of greedy people just want more money" to "this is actually hurting regular people" and our conversations would change to how to combat that without risking becoming China.

Look up the Great Firewall. That is effectively what laws like SOPA and PIPA would have and still could create right here at home. No conspiracy bullshit, for real. And the way it started was the politicians there said it was for "combating piracy and pornography." But the Chinese don't care about pirates so they don't even pay attention to that. They just head straight for the dissenters because they have the power to.

So what I'm saying is a boycott of regular people would make it realer to us and we would take the issue more seriously. And also we have to be extremely careful with laws like these because they can easily lead to abuse no one wants.</comment>


Watch Out, Kindle: Google Makes iPhone the New eBook Reader - <AUTHOR> http://www.pcworld.com/article/159067/

<comment><USER2> This a little ridiculous. Anyone who's seen both a Kindle and an iPhone side by side knows they don't compare. It's pretty hard to imagine someone reading War and Peace on an iPhone, or even the Wall Street journal or something...

</comment><comment><USER3> It also works with the G1, here's the original announcement from google: <http://tinyurl.com/cvlxmu></comment>


Show HN: Export all Digg Reader data - <AUTHOR> https://github.com/sangupta/digg-reader-dump <comment><USER2> I finally got back into RSS and started using Digg Reader less than a week before getting the notification it was shutting down.

Sigh...

What even are the options for free RSS readers these days?

<comment><AUTHOR> The ones I use MultiPLX (multiplx.com, for everything), InoReader (inoreader.com, for mailing lists).

<comment><USER3> Good lord, why is multiplx in that horrible pinterest style layout?

<comment><AUTHOR> They have multiple layouts that they support - I prefer the normal list layout that shows the title and snippet.</comment></comment></comment></comment>


Quake's Fast Inverse Square Root - <AUTHOR> http://betterexplained.com/articles/understanding-quakes-fast-inverse-square-root/

<comment><USER2> This is a good thing to know about, but bear in mind that these days it's often slower than just using whatever built in square root you have access to. Especially beware in languages where you need to do something more than a cast to get the raw bits out of the floating point number, oftentimes that alone is enough to kill any performance gains you might otherwise see. Profile your code before and after, and make sure you've got an easy way to switch back if you realize that you've gone and made things slower (or worse, too inaccurate for your use case).

If this was a universally effective optimization with no potential downside, it would already be built in to your standard math library...

<comment><USER3> This isn't a universally effective optimization. It's an exquisite optimization for when a little imprecision is tolerable. Micro-optimizations like this are rarely worth the increase in cognitive complexity of the code, but Quake had to do a lot of math in very little time on 1996 hardware, so I'll trust Carmack (whose programming skills are legendary if you aren't familiar with him).

<comment><USER4> Carmack didn't write that code. It was written by Greg Walsh.

</comment></comment></comment><comment><USER5> Also see: <http://en.wikipedia.org/wiki/Fast_inverse_square_root>

And for more analysis and improvements see those papers:

<http://www.lomont.org/Math/Papers/2003/InvSqrt.pdf>

[http://www.daxia.com/bibis/upload/406Fast_Inverse_Square_Roo...](http://www.daxia.com/bibis/upload/406Fast_Inverse_Square_Root.pdf)

[http://www.geometrictools.com/Documentation/FastInverseSqrt....](http://www.geometrictools.com/Documentation/FastInverseSqrt.pdf)

</comment><comment><USER6> Huh. The only really interesting part of the algorithm is the initial guess with the magic number, and he doesn't go into that part at all. Read Chris Lamont's paper if you care enough to want to understand it. The only downside to Lamont's paper is that it's a post mortem analysis rather than a pedagogical derivation. I worked out a step-by-step development of the algorithm last year, but I've never gotten around to writing it up in tutorial form.

</comment><comment><USER7> Obligatory XKCD reference:

<http://xkcd.com/664/>

Image text: Some engineer out there has solved P=NP and it's locked up in an electric eggbeater calibration routine. For every 0x5f375a86 we learn about, there are thousands we never see.

</comment><comment><USER8> This is the kind of article I come to Hacker News for. A clever hack for a real-world problem with an excellent explanation.

<comment><USER9> You might also be interested in the previous HN discussions of the same topic, then: <http://news.ycombinator.com/item?id=896092>

(yes, this "trick" has been making rounds for a decade now; I predict another HN article within 6 months)

</comment></comment><comment><USER10> Every time I read the headline for a fast algorithm for inverse square root I think "Well, yeah, you just multiply the input by itself. Can't get much faster to undo a square root than that." Silly me.

<comment><USER11> My native language isn't English, and I made the very same mistake like 50 times already. Sometimes I still forget what inverse means in math. I would instantly understand "reciprocal" though, which is the name I learnt for this operation.

<comment><USER12> >Sometimes I still forget what inverse means in math.

I think your interpretation is actually the more correct one, here. Squaring and square-rooting are the inverse of each other.

They are really talking about calculating the reciprocal of the square root of X. They are calling it the 'inverse square root', but thats just them abusing terminology, which people do all the time, rightly or wrongly.

But you weren't wrong to be initially confused by this abuse of terminology, and it doesn't have anything to do with your native language not being English.

<comment><USER13> I thought the same thing. I guess the confusion comes from thinking of the inverse of the function square root instead of the multiplicative inverse of the value of the square root function. Technically I suppose the terminology is a bit hand-wavy, since you could have also been referring to the additive inverse, but I think it's fairly common to talk about "inverses" of members of a field and assume that people know you mean multiplicative inverses. But that's exactly what isn't a safe assumption here, since you could be thinking about a function (which seems like the more natural interpretation), as opposed to a number.

</comment></comment></comment></comment><comment><USER14> I love that this comes up regularly in this community. It's one of those things that everyone seems to discover at some point.

</comment><comment><USER15> The most useful modern-day knowledge you could gain from this is here: <http://www.sosmath.com/calculus/diff/der07/der07.html>

(Newton-Raphson Method)

</comment><comment><USER16> Relevant link for those who want to know more about who came up with the magic number. <http://www.beyond3d.com/content/articles/15/>

</comment><comment><USER17> <http://news.ycombinator.com/item?id=419166>

</comment><comment><USER18> Awesome writeup, thanks!

Came across something similar a couple of days ago while browsing the source code of Marathon (one of the early games of Jason Jones and Bungie, later of Halo fame). At the time, Bungie were the Mac equivalent of id software, and Jason Jones the equivalent of John Carmack.

[http://marathon.svn.sourceforge.net/viewvc/marathon/branches...](http://marathon.svn.sourceforge.net/viewvc/marathon/branches/aleph- source/Source_Files/Misc/world.cpp?revision=3&view=markup) (look for isqrt())

There's a great explanation in the comments.

This code was most likely written by Jason, probably around '93-'94.

</comment><comment><USER19> Which came first? Quake 3 or the papers? This defines how interesting it is. I've seen a lot of folks working through Quake's code lately. Hard to tell if they are originators or appliers, but either way it's much more interesting than reading bland examples from a book.

</comment><comment><USER20> Not Quake, but Quake 3. That's one and half generation of engines ahead.</comment>


Write AWS CloudFormation templates in Python - <AUTHOR> http://answersforaws.com/blog/2013/10/cloudformation-templates-with-troposphere/

<comment><USER2> This is great. I am just starting to learn Cloudformation and will be quite helpful for me.

Also, what's your opinion on using boto instead of cloudformation? If you use boto with ansible, all your infrastructure code is in python and in a single code base.

<comment><AUTHOR> boto is great and I am a big fan of it. I think the combination of troposphere and boto is very powerful. Using boto along can certainly get the job done, but: \- it will take longer to come up as calls will happen in serial (CloudFormation does parallel execution) \- you will have to do your own dependency management (not hard, just get the order right) \- you will have to do your own teardown when you are finished with the resources (this is why I would use both)

Hope that helps.

<comment><USER2> Thank you.</comment></comment></comment>


50k-year-old three-ply cord fragment found at Neanderthal site - <AUTHOR> https://www.bbc.com/news/world-europe-52267383 <comment><USER2> _"Given the ongoing revelations of Neanderthal art and technology, it is difficult to see how we can regard Neanderthals as anything other than the cognitive equals of modern humans, " the study said._

I don't keep a finger on the pulse, but seeming advances in the study of Neanderthals have been noticeable from browsing HN alone this past decade.

Are there any books or resources that look to bring a layman up to speed on the changes to and current state of the field, similar to what _Mann's 1491_ did for pre-Columbian studies back in the day?

I've turned up _Pääbo's Neanderthal Man_ before, but it was focused on genetics, and could be quite technical.

<comment><USER3> It is difficult to see how we can regard Neanderthals as anything other than "the same as today just many years ago"

At the risk of being disdained by "science", I never bought the idea of pre- historic human subspecies.

The reason being is that I cannot fathom the evolutionary event that would cause our brain to develop in such a way that we evolved from "smart enough to outsmart all predators" to "completely dominate the earth and the elements".

There hasn't seemed to exist any such predator or environment where such a huge jump in brain capacity would be required.

<comment><USER4> >completely dominate the earth and the elements".

I think that depends on how you look at it. If we're going by pure numbers, bacteria win by a landslide. Then we've got fungi which come pretty close to competing with bacteria for most numerous and widespread.

Ants probably have us beat too along with a few other insects.

But to address the point you were making. It didn't happen all at once. It was a long gradual process that occurred with huge overlap between different hominid species. The 'jump' in brain power wasn't a jump, but a slow process of selection where smarter individuals would outcompete the less intelligent ones.

For example, they would possibly hunt more efficiently, using tools and having a better memory for migration routes, they would have a better memory for dangers etc. Over time individuals better suited to this would mate and breed with others, this in turn would pass those traits on to offspring while individuals who couldn't compete would be left out and over millions of years of this and constant adaptations acquired because of this, humanity got smarter.

<comment><USER5> You haven't mentioned what to me is a much more important evolutionary pressure: other humans. Politics is a feature of the ancestral environment. Humans aren't smart because they need to out-compete other species, or a harsh environment. Other animals do this as well, and none of those are as smart (sorry octopi, elephants, dolphins and crows). Humans are so intelligent because they had to out-compete each other, in a positive feedback loop that produced where we are at today

</comment></comment></comment></comment><comment><USER6> 0.5mm wide is very thin indeed, especially as it's made out of even 3 fibres. Finer than anything I'd expect to be handmade but IANANeanderthal.

<comment><USER7> I saw that to, but it seems clear that's the sizes now? I guess it was bigger and most of it has rotted away? But also IANANeanderthal.

</comment></comment><comment><USER8> For a second there was thinking Live, Neutral, Earth?!? Wow these Neanderthals were far ahead...

<comment><USER9> No, they were even more advanced: Fire, Wind, Water, Earth

</comment></comment><comment><USER10> > Three groups of fibres were separated and twisted clockwise in an "S-twist". > Once twisted, the strands were twined anti-clockwise in "Z-twist" to form a > cord.

And hardly could they imagine the academic language used in analysing their handy work.

</comment><comment><USER11> I think it's fairly obvious there was a giant blood war between the neanderthal and homo sapiens early on. And a mass extinction of neanderthals. Simply because they were different. If anyone has more information about it, I'd love to hear more.

<comment><USER12> A sizeable chunk (like 1-4%) of our DNA comes from Neanderthals, and there's recent evidence that they produced offspring with humans. The two coexisted and interbred for many years.

[https://en.m.wikipedia.org/wiki/Interbreeding_between_archai...](https://en.m.wikipedia.org/wiki/Interbreeding_between_archaic_and_modern_humans)

</comment></comment><comment><USER13> I wonder if it was null terminated.

<comment><USER14> I'm putting a three-ply cord fragment to thwart you guys in the title above.

</comment></comment><comment><USER15> Will Blavatsky have the last laugh?

</comment><comment><USER16> Is there link to this story on something other than ultra-mainstream media?

<comment><USER17> Here's the actual paper:

[https://www.nature.com/articles/s41598-020-61839-w](https://www.nature.com/articles/s41598-020-61839-w)

Hardy, B. L., Moncel M.-H., Kerfant C., Lebon, Bellot-Gurlet M. L., & Mélard N. (2020). "Direct evidence of Neanderthal fibre technology and its cognitive and behavioral implications." _Scientific Reports._ 10(4889).

</comment></comment><comment><USER18> This seems a stretch. The art, craft and social structures of Neanderthal can only be seen as 'very primitive' compared to modern humans. This PC insistence on making them seem 'as smart as us' does no service to science.

They are similar in kind to us, in that they could master (simple) crafts. But evidence shows they often learned it from Homo Sapiens, and imperfectly at that.

</comment><comment><USER19> I have friend who does genetic testing and had person who wasn't matching sapiens genome and compared to Neanderthal with much better match. Out of curiosity found Facebook profile and they look like Neanderthal. Is it possible that they aren't exinct?

<comment><USER20> IANAGeneticist but afaik it is known that there was interbreeding between modern humans and neanderthals and there are populations in Europe and Middle East with genetically discernible neanderthal ancestry, still your observation that they "look like a Neanderthal" is probably affected by confirmation bias.

<comment><USER21> Actually all that is known is that there is shared genetic sequences that indicate interbreeding as one possible scenario. I've heard others make the claim that the same phenomenon could have been caused by populations of sapiens that had archaic genetic features (that is shared by both sapiens and neanderthal) from much further back.

I expect the genetic picture is far more complicated than we thought or think, and "interbreeding" is a simplistic way of talking about populations. Species are, after all, a taxonomical concept we invented, not an actual thing in nature. The lines are far more blurry.

<comment><USER20> No disagreement there, just pointing that interbreeding is a natural default hypotheses given that we know that at some point their living areas began to overlap and the Neanderthals eventually disappeared as a distinct species by that taxonomy - the debates afaik are about the scale of the phenomena that is whether they were mostly absorbed by modern humans or mostly driven to extinction or even killed by them.

<comment><USER21> Lots of animals have gone extinct when our range overlapped with theirs :-)

<comment><USER20> Yes but ancient modern humans would have recognized Neanderthals as humans rather than animals even if they had knowledge of other hominids.</comment></comment></comment></comment></comment></comment>


Breaking News: Box Secures $150 Million in New Funding - <AUTHOR> https://vcexperts.com/reference/buzz

<comment><USER2> There's a redirect back to the home page when clicking on this link.</comment>


Fast Inverse Square Root Function - Seems to have been created for Quake - <AUTHOR> http://www.scribd.com/vacuum?url=http://www.lomont.org/Math/Papers/2003/InvSqrt.pdf

<comment><AUTHOR> The PDF: <http://www.lomont.org/Math/Papers/2003/InvSqrt.pdf>

<comment><USER2> It is at the point now where I click on the comments for every scribd.com story to see if someone has pasted in the original pdf url. Never fails.

<comment><AUTHOR> I've noticed everyone likes the PDF version. It's trivial to add it as a comment since I have it copied in the clipboard from creating the submission - it's my standard practice now.

<comment><USER3> Then why not submit the direct PDF link in the first place? Or is it a 'helpful' news.yc antifeature?

(PDF readers actually load faster than scribed, provided you aren't using the vanilla Adobe one with all the plugins turned on.)

<comment><AUTHOR> It's a "helpful" feature. All PDF links are auto converted to scribd.

<comment><USER4> It would be more useful if the original hyperlink to a PDF file was preserved and a hyperlink to scribd was also presented. This would also eliminate a problem with duplicate hyperlink suppression.

</comment></comment></comment></comment></comment></comment><comment><USER5> The history of this function: <http://www.beyond3d.com/content/articles/8/>

Finding the original author of the function (Greg Walsh): <http://www.beyond3d.com/content/articles/15/>

</comment><comment><USER6> If you just want the big picture, this link is easier to skim:

[http://betterexplained.com/articles/understanding-quakes- fas...](http://betterexplained.com/articles/understanding-quakes-fast-inverse- square-root/)

</comment><comment><USER7> No. The "inverse square root function" is the "square function."

What you want is a function that gives the inverse of a square root.

Mathematical terminology sucks.

<comment><USER8> I was thinking the same thing.

      int inverse_square_root(int x) { return x * x; } // patent pending

</comment></comment><comment><USER9> great... now we can have all the posts that repeat every 3 months on programming.reddit repeat here too! YAY for signal:noise.

<comment><USER10> Just don't upvote the submission. If it's a major dupe, it will get off the front page very quickly.</comment></comment>


BMI in the U.S.: 1882-1986 - <AUTHOR> http://www.nber.org/papers/w16252

<comment><USER2> I can only access the abstract, but this is fascinating: "[t]he highest centile increased by some 18 to 22 units in the course of the century". An increase of 22 units runs the gamut of possible BMI values [1], from severely underweight to obese class 2. It's equivalent to gaining 170 lbs (for a 5' 11" person).

[1]: <http://en.wikipedia.org/wiki/Body_mass_index></comment>


Locked in the Ivory Tower: Why JSTOR Imprisons Academic Research - <AUTHOR> http://www.theatlantic.com/business/archive/2012/01/locked-in-the-ivory-tower-why-jstor-imprisons-academic-research/251649/ <comment><USER2> This is analogous to the Hollywood debate that's going on right now. It's a similarly broken model that can benefit from some startup help.</comment>


Log-structured file systems: There's one in every SSD - <AUTHOR> http://lwn.net/Articles/353411/

<comment><USER2> Can a single post make you smarter? This was an awesome description of why log file systems match with SSD (as long as TRIM is part of the picture). It also covers how flash based memories work in practice (small reads, but block writes).

Very fascinating stuff for a guy that only does simulations software, but was once super curious about electronics in junior lab physics (nand gates, opamps, feedback circuits).

Great SSD video (the 24 raid 0 setup) [http://www.youtube.com/watch?v=96dWOEa4Djs&feature=playe...](http://www.youtube.com/watch?v=96dWOEa4Djs&feature=player_embedded)

<comment><USER3> Valerie Aurora articles have gotten good reviews here before eg <http://news.ycombinator.com/item?id=735982>

An SSD is already like a raid 0. This is a Samsung block diagram of what's going on inside <http://www.pcper.com/images/reviews/766/SSD-Samsung.png>

</comment></comment><comment><USER4> A reckon a battery backed RAM/SDD hybrid would be the fastest option available. I did search and found a 4G one that was selling for thousands of dollars (can't find the link now). They said that it could back up the whole of RAM to SSD in 60 seconds so the data security (with a reliable battery) would be pretty good. Should scale as well with the same amount of time required for more lots of 4G. I can't see any reason why this should have to cost so much though. 4G SSD + 4G RAM + Battery + Controller < thousands of dollars. Must still be in the 'paying for the innovation' stage I guess.

<comment><USER5> Acard (acard.com) sells battery backed RAM/CFcard solutions for well under $500. There are compromises. It will fit your budget, but may not fit your needs.

<comment><USER4> Thanks for that. This page has a clearer description than the companies web site.

<http://2xod.com/articles/ANS_9010_ramdisk_review/>

Seems like it wouldn't be too hard to build this into motherboards so you could essentially have non-volatile ram for whatever purpose you wanted.</comment></comment></comment>


Mail.app implemented on the web using ukijs  - <AUTHOR> http://blog.ukijs.org/2010/04/08/mail-app-on-the-web/

<comment><USER2> I think that building web apps that look/feel like desktop apps is a step in the wrong direction. Some of the best web apps around like Gmail, Maps, Facebook, Twitter, Wordpress etc represent a complete break from traditional desktop software and I actually like that.

You can almost think of the browser viewport as a blank canvas on which you can draw pretty much anything. Desktop apps feel much more constrained in terms of UI & appearance. I think web apps - if done right - look and feel much better than most desktop apps anyway.

Not to take way from what the OP accomplished.. That's some serious javascripting and I like his approach much better than Cappuccinos

<comment><USER3> The best example of this is forward/back buttons - these don't exist on the desktop, but are integral to the browser experience.

<comment><USER4> Undo/Redo ?

</comment></comment></comment><comment><USER5> You can play with the actual demo over here: <http://ukijs.org/mail/index.html>

It seems pretty interesting.

<comment><USER6> It's interesting, but not very deep in terms of functionality.

The main exhibits here are the split panel view and the table view. Both are OK, but these problems have already been solved many times by ExtJS, Dojo, and various jQuery plugins, most of which implement many more difficult features like sorting, searching, editing, and saving state.

All else to be seen here is the meticulously reproduced skin with CSS and background images.

Things I would have been excited to see, because they are not yet well-solved amongst JS frameworks: tokenizable editable text fields, like the real Mail.app's To: field, attachments using HTML5 D&D, a quickly-searchable inbox and a drag & drop sortable treelist view for the mailboxes.

<comment><USER7> I actually think it shows a lot of promise. Though it is reasonably limited, a lot of what it does do it does well. For example, it doesn't have the _extremely common_ problem of every piece of text being selectable, and often that selection fundamentally breaking other interactions like drag and drop.

<comment><USER8> Disabling text selection is actually really simple. All you need to do is apply user-select: none (currently available as -webkit-user-select and -moz- user-select) to the element.

</comment></comment></comment></comment><comment><USER9> I have to admit that is quite fast, and the GUI is pretty. Nice job.

</comment><comment><USER10> I'm a little confused. The blog post states:

> "Models store, load and transform the data from the server."

But the ukijs.org states:

> "Uki doesn't want to be a Jack-of-all-trades. It only does layout but it > does it well. You won't find any ajax or data storage layer code here."

Which one is it?! (I'd much prefer the former)

<comment><USER11> Both. He's saying that models (in general) handle data, but Uki (in specific) doesn't specify how you should go about doing that.

<comment><USER12> The data.model file is about 100 lines of code

</comment></comment></comment><comment><USER13> _What this basically means is that you have to do more: read more source, learn more conceptions and tools, support more code, fix more bugs._

I think the biggest advantage to Cappucino is that, if you already know the Cocoa framework, there is less to learn.

<comment><USER10> True. But if you're already developing for the web, chances are you know JavaScript better than you know Cocoa.

<comment><USER10> Side Note: One of the major draws for me to learn Objective-J (coming from a Ruby/JavaScript background) was that I simultaneously learned a lot about Objective-C and Cocoa, which is key for iPhone/iPad apps.

I felt like I was double dipping courses in college again.

<comment><USER7> More of our biggest users came from pure web backgrounds then from Cocoa backgrounds.

</comment></comment></comment></comment><comment><USER14> How theme-able is it?

</comment><comment><USER15> Disclaimer: I'm one of the co-founders of NOLOH (<http://www.noloh.com>).

I want to apologize in advance for being so brash. I find that these demonstrations are very misleading. We all ohh and ahh, but not because of the technical accomplishment, but because of the beauty of Mac interfaces. First, sure the app is fast, it's loading the entire application from JavaScript, yet another fat client app.

Second, the capabilities that this provides seems no different than the basics of YUI, or other JavaScript widget collections with unified syntax.

Third, it's misleading to suggest that this is Mac Mail when in fact I can't search. I guess that's not a part of the Mail.app.

Fourth, 15 hours to do a main screen and a new message form, really? I'm sure that we or the guys at Cappuccino & Sproutcore could throw a similarly functioning demo together quicker.

The hard part of this example is getting the image resources, not the implementation. This implementation could've been done just as well in straight JavaScript or any other JavaScript framework just as nicely.

<comment><USER16> I really see no reason for being an ass like this. The guy made something, embrace it or leave it. Constructive criticism is valuable, but telling "…I can do it better" serves no other purpose than being negative.

<comment><USER17> I think the point is, the title "Mail.app implemented on the web using ukijs" is wrong.

It's pretty easy to clone a UI so something looks like something else. It's easy enough to then add a bit of data so it sort of feels like it as well. But building a real world fully functioning app takes a bit more work.</comment></comment></comment>


'The Female Factor' And Other Proven Tricks To Get Into Y Combinator - <AUTHOR> http://www.forbes.com/sites/meghancasserly/2012/10/02/the-female-factor-and-other-proven-tricks-to-get-into-y-combinator/

<comment><USER2> Interesting article. However, I'm a little surprised that an article about women at ycombinator didn't include Paul Graham's own rumination on the issue...

<http://paulgraham.com/ideas.html>

"This is one reason Y Combinator has a rule against investing in startups with only one founder. Practically every successful company has at least two. And because startup founders work under great pressure, it's critical they be friends.

I didn't realize it till I was writing this, but that may help explain why there are so few female startup founders. I read on the Internet (so it must be true) that only 1.7% of VC-backed startups are founded by women. The percentage of female hackers is small, but not that small. So why the discrepancy?

When you realize that successful startups tend to have multiple founders who were already friends, a possible explanation emerges. People's best friends are likely to be of the same sex, and if one group is a minority in some population, pairs of them will be a minority squared."

</comment><comment><USER3> When I applied, I didn't even think about the fact that I'm female. This article has me super-excited.

I'm surprised it's so low. My guess is that:

1) As geebee said, groups of coding girlfriends are rare (I'm the only one of my girlfriends who's into tech stuff)

2) Women don't like peacocking as much as men, so they suppress a lot of great ideas

3) If women have babies in their twenties, that becomes their first priority

Otherwise, I'm psyched to be a female applicant at this moment of opportunity.</comment>


40th anniversary of the Rubik's Cube - <AUTHOR> https://www.google.com/webhp?tab=ww&ei=1AZ6U5_BI8mYqAavvoKACg&ved=0CBYQ1S4

<comment><USER2> Unfortunately it forcing me to use Chrome, Firefox, or Safari even though I am using the latest Chrome on Ubuntu 13.10. Too bad.

<comment><USER3> Ditto, only I'm on Debian. Just updated to 34.0.1847.137

</comment></comment><comment><USER4> Sadly, my original cube from 1980 broke last year. The plastic just gave way on the center rotating "star" and it came apart. :(

I bought a new one, but it's much harder to turn. I think I may have put some Vaseline in the original to lubricate it, but it's been too many years to remember.

I wonder if Dr. Rubik is getting his royalties now that the Soviet Union is gone (The story I heard was that the Soviets kept all the royalties, giving him a relatively generous salary in return).

<comment> atom-morgan I'd recommend a silicone based lubricant. Jig-a-loo works very well. I used to compete, so I've used a few.

</comment></comment><comment><USER5> When I was 5, my parents promised me a Rubik's cube if I came along with them and moved to the United States. I never realized it was a fairly new product back then. 40 yrs and still going strong - how many other "toys" have those legs?

</comment><comment><USER6> A dupe of [https://news.ycombinator.com/item?id=7765879](https://news.ycombinator.com/item?id=7765879).

</comment><comment><USER7> After solving the cube, it doesn't let you share the completed screenshot...

</comment><comment><USER8> window.solveCube() if you want to cheat.

<comment><USER9> TypeError: undefined is not a function

<comment><USER10> You have to switch to the iframe's context.

</comment></comment></comment><comment><AUTHOR> Click outside the cube to rotate the whole cube. If anyone has time to solve it please post a screen shot.

<comment> atom-morgan The controls make it really hard but here you go: [http://imgur.com/o8YILYY](http://imgur.com/o8YILYY)

<comment><USER11> Use the keyboard! Once you got the focus out of the instant search box, all of the following work almost as you expect: UuRrLlFfDdBb for face rotation, MmEeSs for slice rotations and XxYyZz for cube rotations. (upper-case for clockwise, lower-case for counterclockwise)

I got it down to 19 seconds using the optimal solution from [http://www.speedsolving.com/forum/showthread.php?47666-Googl...](http://www.speedsolving.com/forum/showthread.php?47666-Google- Doodle-Rubik-s-Cube&p=979211&viewfull=1#post979211)

I'm not doing it again, the interface is too frustrating.

<comment> atom-morgan I should have known better. Thanks. It's a shame the cube always scrambles to the same state.</comment></comment></comment></comment>


Ask HN: Why does running a few instances of DIR /s in Command prompt load CPU heavily? - <AUTHOR>

Opening 3-5 windows command prompt and running DIR /S to list all subdirectories increases CPU load to 80%. I have seen this type of significant load on the CPU in different platforms. Any idea why a simple task like directory listing consumes so much CPU? <comment><USER2> That's because you are the only user on the system and you're asking the filesystem to tell you everything it knows about all your files.

Strictly speaking it is an io-bound operation, but with the number of files on your machine and some aggressive caching it will quickly turn into a memory- to-display translation (involving lots of font rendering and scrolling) and that is cpu-bound, not io-bound.

Look at it this way, the 'idle' process also consumes lots of cpu power, but it does absolutely nothing. When you're alone on a machine you have the power to max it out with anything cpu bound, no matter how simple. A loop that counts from 0 to 1.000.000.000 (assuming it's not optimized out) will consume 100% cpu time unless you tell your system explicitly otherwise.

The only way to _not_ max out the cpu is to deliberately slow the process down by installing small sleep periods in between operations, but you really want your 'dir /s' to run as fast as it can.

<comment><USER3> Indeed - as an experiment, try doing the same with all your CMD windows minimized.

<comment><AUTHOR> Thanks</comment></comment></comment>


The craziest Javascript implementations - angry-hacker http://yeblon.com/the-craziest-javascript-implementations

<comment><AUTHOR> Disappointed! I thought this was about the craziest JavaScript runtimes (and potentially compilers), but it's a couple of JS _programs_.</comment>


Ask HN: Options for foreign hackers looking to work in the US? - <AUTHOR>

Using a throwaway because I don't want the discussion to be centered around me personally (although my account is 1k+ days old)
I'm sure I'm not alone in being frustrated seeing all of these posts and discussions on how hot the job market is for software developers in the US.
Rather than suffer in silence, I figured we could have a real discussion about what the practical options are for those of us who are non-US citizens.
If the market is as crazy as everyone seems to be saying lately, why aren't more US startups looking to hire people from abroad?
Is it impossible for a startup to sponsor an employment visa?
For those of you who are not native US citizens but are currently working in the US, how did you get there?
What is a realistic way for a skilled software developer to come to the US? <comment><USER3> I am also interested on more information on this matter. I see some companies specify in the job post that they are willing to help you relocate but haven't heard much talk about this.

I know this process is not really cheap (+20k) for the company and surely not a walk in the park but would it be more appealing for the company if the job applicant would agree to pay all the expenses related? Possibly this way it will (I think) be treated as any other local applicant.

Are there any other road blocks beside the costs involved? How long would the process take (without the interview)?

</comment><comment><USER4> I am not an expert in the matter but here is what I have learnt/heard about it:

\- There are costs involved in the whole process, I usually hear 15K-20K (could be more)

\- Committing ~20K upfront for an employee who you don't know much about involves risk. Hiring & firing becomes complicated and involves attorneys.

\- Depending on what country the employee is in, there are different quotas for visas and they fill up very quickly. I know this is the case for India, not sure about other countries.

\- Another potential problem I can think of is what percent of your workforce is non-US. I believe there are laws around that too.

All this being said, I have thought about this and a few of my founder friends. Most of the H1B hires I have seen is students who come to US for MS and get the visas. I don't know anyone who was hired from their native country and relocated to US. There might be some cases though.

<comment><USER3> Yes, the risks are high for the employer especially if it comes to such high fees, so I assume by letting the employee to make the pay, there won't be any (high) risks. Of course this might not be possible for everyone but would be good to have it as an option.

Will just assume that getting the Visa won't be a problem. At least in my country not.

Hopefully will have the _pleasure_ to try the system soon.

</comment></comment><comment><USER5> The most common way is to come to the US to study first, say for a Master's degree, and then look for a job while still in the US, before graduation.

Other than that, you have to look for a company that would hire you from overseas and sponsor an H-1B visa. The company has to prove that it couldn't find any qualified Americans to do the job.

This might be difficult, especially if a face-to-face interview is required, which it is in most cases. Then, to come for a face-to-face interview to the US, you legally must not have an intention to stay and work in the US, since you're coming as a "visitor/tourist". It's a Catch-22 situation.

<comment><USER6> _The company has to prove that it couldn't find any qualified Americans to do the job._

Can you please link to an official document that states this? Because i thought the only relevant clause was not paying the Visa holder less than what an American would get. In other words, the Visa sponsor must pay market rates.

Edits: Sorry, bad connection.

<comment><USER5> Sorry, I gave wrong information. For H-1B, the company doesn't have to prove this. I confused it with an employer-sponsored green-card application process.

</comment></comment></comment><comment><USER7> If you're a dev that is good enough to work for a solid startup then you have the (technical) skills to found a startup yourself. Don't have any ideas? I'm sure there are entrepreneurial people in your country who look for technical co-founders.

</comment><comment><USER8> Personally, I think that a good compromise is for foreign devs to become technical co-founders with others who are based in SV.

The issue is that all the devs here have a great job market to pick from - <USER2> there are a ton of startups looking for technical folks who cant compete with BigCo for devs.

Further, there is so much energy (money, interest, thought, etc) flowing in the startup space right now. Get into/form a company here - build an MVP, get funding, sponsor your own visa or at least regular visits (trust me, the living costs are really high here).

I know I am looking to connect with people.

<comment><USER5> This is nearly impossible with current US immigration laws. You can be a founder of the company (i.e. an investor), but you cannot legally work for the company, or you violate your visitor immigration status.

<comment><USER9> Not convinced that's true, what's the reasoning that your own company can't sponsor your visa ?

<comment><USER5> [http://www.quora.com/Can-a-H1B-holder-work-for-a-startup- as-...](http://www.quora.com/Can-a-H1B-holder-work-for-a-startup-as-a-co- founder)

<comment><USER9> That would only seem to apply in the case where you own the majority of the company, so it wouldn't seem to apply to cases where >2 co-founders or 2 co- founders + investors exist.</comment></comment></comment></comment></comment>


Five methods for Filtering data with multiple conditions in Python - <AUTHOR> https://kanoki.org/2020/01/21/pandas-dataframe-filter-with-multiple-conditions/ <comment><USER2> Title should probably clarify that this is with Pandas, that's much more specific and less generally useful than "in Python".

Original title: "Pandas dataframe filter with Multiple conditions"

</comment><comment><USER3> To help readability I tend to do something like this:

f1 = (df["col1"] == condition1)

f2 = (df["col2"] == condition2)

df[f1 & f2]

This is equivalent to the 'pandas boolean indexing multiple conditions' method.

<comment><USER4> I do the same without the parenthesis.

</comment></comment><comment><USER5> This is probably gonna be sacrilege to the Pythonians, but I often wish there was support for some SQL-like syntax when working with (pandas) data frames. It certainly would make the process a lot smoother for some tasks.

<comment><USER6> I'd love if someone took the next step from Pandas being influenced by R to port dplyr-esque syntax to it.

<comment><USER7> I've been working on a library over the past year that does exactly that, including generating dbplyr style SQL queries!

Would love your feedback :)

[https://github.com/machow/siuba](https://github.com/machow/siuba)

<comment><USER8> This looks interesting! Can I ask, what's the origin of the name? Both "siu" and "siuba"? Would be a useful addition to the docs, IMO.

<comment><USER7> Ah, thanks for pointing out the lack of explanation. I'll add one to the readme.

It's a transliteration of the cantonese word for minibus, 小巴 :).

edit: siu (小) means little!

</comment></comment></comment></comment></comment><comment><USER9> This seems to be about doing filtering with Pandas, not pure python. The title should probably be changed to reflect this.

</comment><comment><USER10> Yeah it looks like his code that this person uploaded isnt escaping the HTML or is being unescaped when it should be escaped.

df.loc[(df['Salary_in_1000']>=100) & (df['Age']< 60) & (df['FT_Team'].str.startswith('S')),['Name','FT_Team']]

</comment><comment><USER11> Would have been nice to see a comparison of performance, or at least which is suggested style.

<comment><USER12> My guess is that eval and query have the worst performance, since they need to be interpreted first. As for the other methods, I'm not too sure how they rank. Personally, for style I agree with the first comment on the linked page, which is to split up the conditions for readability:

      f1 = (df["col1"] == condition1)

      f2 = (df["col2"] == condition2)

      df[f1 & f2]

</comment></comment><comment><USER7> One thing that really surprises me: NONE of these methods work with grouped DataFrames.

But grouping data is extremely common in data analysis.

Basically, the strategy with grouped data, is taking the loc approach, and sprinkling in a bunch of additional .transform calls. :/

<comment><USER13> I wonder if this could be improved with SQL

</comment></comment><comment><USER14> I strongly prefer .query() for legibility and that it can but used in a pipe. My only problem is that often flake8 will not detect the use of a variable inside of the query string. Has anyone else come across this before?

<comment><USER15> If you supply a function to `.loc`, you can use it in pipes pretty easily. E.g.

``` my_dataframe.loc[lambda df: df['col'] > 0.8] ```

Would this help work around your issue?

</comment></comment><comment><USER16> Some speed comparison on a larger dataset would be interesting</comment>


The Local-Global Flip, or, "The Lanier Effect" - <AUTHOR> http://edge.org/conversation/the-local-global-flip

<comment><AUTHOR> A little meatier than most articles, but definitely worth the read.</comment>


Ask HN: DevOps portfolio to impress - <AUTHOR> If you were looking to hire a DevOps professional, what would you be most impressed by?<p>A video showing an example for a complete CI/CD deployment? Articles? Cloud certifications? The interview alone? <comment><USER2> Here's a good article about hiring a DevOps: [https://medium.com/aws-activate- startup-blog/hiring-a-cloud-...](https://medium.com/aws-activate-startup- blog/hiring-a-cloud-engineer-questions-to-ask-and-what-you-should- hear-12a960d97163)</comment>