skysight-inc/HackerNews huggingface dataset:
The fine print only applies to contracts. Requests like this, job applications - basically all cattle calls - people will call them like they see them. They're painting a picture of what they want as well as they can.
Holy crap. I was about to comment that NANs are not equal to each other, as is the case in every other floating-point representation on the planet[0]. I wasn't actually expecting the page to say either way, but I decided to have a quick look in the vague hope of finding a quote to support that, and instead discovered:

"nan is equal to itself."

That strikes me as being very odd, and will likely catch a lot of programmers out who are expecting the "normal" behaviour there. I predict many bugs, and much wailing and gnashing of teeth, as a result.

[0] Maybe.

Edit: I see Stormbrew made the point before me, lower down the thread.
> Those cases would jump to a previously configured operation table for software helpers.

What you want is called software interrupt or exception. MIPS and Alpha can do it for integer overflows. SPARC can do it for the two bottom tag bits of integers (to distinguish integers from pointers). I bet that if you only wait long enough, you will eventually see an architecture with both features. ;-)

In the meantime we have to fall back to conditional jumps. :-/
I had to search a lot to find the some context information. This message is apparently relevant: http://lists.scheme-reports.org/pipermail/scheme-reports/201...
So as I understood you wanted the ability to generate nice-looking report from your data?

So you had to resort to making extremely small cells to allow for precise positioning of elements, correct?
787 to SFO detours to Honolulu after pilot reports unspecified 'engine failure'
Ubuntu, Redhat/Centos, and SUSE
I live in Vancouver. Blue sky is something you go on vacation to see. :)
BTW, what were the main difficulties/problems in implementing your project using spreadsheets?

I assume that one of these was having to write Ruby scripts to connect things together instead of working directly with your data sources, was there anything else?
> Interesting approach, rather than normalize to 1 it normalizes to the largest whole number. The positives of this are that you don't run into issues with encoding things like .1 that you do in binary

Nonsense. Binary floating-point too normalizes to the largest possible significand. It then omits the leading 1 from the representation, since the leading 1 is by definition a 1. That this trick is simple to pull in binary is only one of the advantages of a base-2 floating-point representation.

The fact that 0.1 is not representable in binary has nothing to do with the choice of representing it as 0x1999999999999a * 2^-56, because it already is, and that does not make it representable.
I'd like an explanation also.

From my own understanding, an operation will lose precision iff () the result cannot be represented with 52 significant coefficient bits. Logically, the same happens in IEEE754, the difference is that the loss of precision in DEC64 is always a multiple 3.5 bits, whereas IEEE754 can lose precision in decrements of one bit.

() Maybe excluding over/underflow scenarios.

To clarify, what you say sounds like (I'm pretty sure that's not what you meant) every operation with mixed exponent will lead to loss of precision. From my understanding, that is not the case. It also sounds like every IEEE754 operation with mixed exponents only leads to one bit precision loss while it could lead to much more (in fact to (<total number of fraction bits between the two IEEE754 doubles> - 52).
If investors receive $0 in return for funding movies then why would they continue to fund more movies? You can make a few low budget movies using Kickstarter and similar methods but I don't see how larger budget movies could be made.
My expectations were set by the HN headline: "Hacker News for crypto, security, and privacy." But I see now you didn't submit the item. You might want to consider putting a banner on the site: "Hacker News for Bitcoin". That would make transferring accounts from bitcointalk seem more reasonable.
It looks pretty cool though.
I think CentOS, Ubuntu and openSUSE, as specified in this page: http://training.linuxfoundation.org/ways-to-train/general-in...

>The System Administration courses are written for CentOS 6, Ubuntu 12.04 LTS and OpenSUSE 12

(as the edX course should be the same as the course from the Linux Foundation, I'm assuming this applies as well).
Yea, I've tried, but haven't been able to get anything about this to the front page. Wrote a blog post about it: http://jere.in/lets-make-a-game

I wanted to get the word out earlier, but it's not too late to start and still have a whole 7 days! I'm starting tomorrow morning.
I don't think it's the cost of people. Technology has done a pretty good job of reducing the cost of simple labor. But technology hasn't done a great job of managing complexity. See, for example, the above jab at the "millions of lines of software code" managing the SR-72. That stands in stark contrast to the "keep it simple stupid" motto attributed to Kelly Johnson, the SR-71's designer.
This is some serious amateur hour. The most glaring problem is this:

> There are 255 possible representations of zero. They are all considered to be equal.

There are also 255 representations of almost all representable numbers. For example, 10 is 1 x 10^1 or 10 x 10^0 – or any one of 253 other representations. Aside from the fact that you're wasting an entire byte of your representation, this means that you can't check for equality by comparing bits. Take a look at the the assembly implementation of equality checking:

https://github.com/douglascrockford/DEC64/blob/master/dec64....

The "fast path" (which is ten instruction) applies only if the two numbers have the same exponent. The slow path calls subtraction and returns true if the result is zero. The implementation of subtraction falls back on yet another function, which jumps around even more:

https://github.com/douglascrockford/DEC64/blob/master/dec64....

For most comparisons (no, comparing numbers with the same exponent is not the norm) it will take around FIFTY INSTRUCTIONS TO CHECK IF TWO NUMBERS ARE EQUAL OR NOT. Many of these instructions are branches – and inherently unpredictable ones at that, which means that pipeline stalls will be normal. All told, I would expect equality comparison to typically take around 100 cycles. It's not even clear to me that this implementation is correct because at the end of the subtraction, it compares the result to the zero word, which is only one of the 255 possible representations of zero. The lack of a single canonical representation of any number is just as bad for other arithmetic operations and comparisons, if not worse.

Crockfords bugaboo with IEEE 754 floating-point is bizarre, verging on pathological. He devoted a section in his book "JavaScript: The Good Parts" to a rather ill-informed rant against it. When I saw him give a talk, I took the opportunity to ask him what he thought would be a good alternative to using IEEE 754. His answer was – I shit you not – "I don't know". Apparently this proposal is the answer. No thanks, I will stick with the amazingly successful, ubiquitous, thoroughly thought out standard, that was spearheaded by William Kahan – one of the greatest numerical analysts of all time. Anyone who doesn't appreciate how good we have it with IEEE 754 should really read "An Interview with the Old Man of Floating-Point" [1], in which Kahan relates just how messed up this stuff was before the IEEE 754 standardization process. It should also be noted that there already is an IEEE standard for decimal floating-point [2], which is not only infinitely better thought out than this drivel, but also is already implemented in hardware on many systems sold by IBM and others, specifically for financial applications.

[1] http://www.cs.berkeley.edu/~wkahan/ieee754status/754story.ht...

[2] http://en.wikipedia.org/wiki/Decimal64_floating-point_format
We're Matching
We want Ellen DeGeneres to come to our Medical School Match Day!!!
Why Airplane Black Boxes Fail
thx for your quick reply. obviously a disappointment!. Please can you also tell how could i use the youtube-Dl link you gave away to extract url from flash based sites? Also is there a way to play live videos from youtube in chromecast. Currently, live streams in youtube appear to be unsupported?

thanks again!
The ultimate game experience
HALF PIG HALF FISH
TldrLegal – Software Licenses Explained in Plain English
Create meaningful git branch names easily (using github issues)
> Did you do any programming at all before 31?

No, I didn't. Sorry, I only just noticed my comment had been replied to.
Thanks for that - I posted this in the hope that someone could provide some background.

Unfortunately http://trac.sacrideo.us/wg/wiki/R7RSSmallErrata is currently returning 503.
Providing additional information about the author is a logical fallacy now?

Also, see: http://www.logicalfallacies.info/relevance/fallacists/
He sounds like someone who gave up after attempting to write his first website.

Sure there are some problems but most of the problems that outsiders are talking about make a lot of logical sense once you learn more about how the system works.
absolute rubbish
More information about the "Introduction to Linux" course here: http://training.linuxfoundation.org/linux-courses/system-adm...

This page has a list of the covered topics: http://training.linuxfoundation.org/linux-courses/introducti...
The Yoga 2 Pro (Lenovo) works fine with the latest Ubuntu and Fedora
Dash documentation browser makes 450$/day
I use the term "significand", because the mantissa is logarithmic, the significand isn't.
In this game, the pawns always move one step forward. In chess the fist movements is different. From http://en.wikipedia.org/wiki/Pawn_(chess)

> Pawn movement: A pawn can move to the square directly in front of itself, if that square is clear. A pawn on its starting rank has the option of moving two squares.
While I understand the choice...I'm confident Debian is more popular than OpenSUSE at this point in history, at least in every market we work in (web hosting, mostly). We have tens of thousands of installations (or 1+ million, if you count Webmin, but we have much less OS data for that). OpenSUSE installs can be counted on a couple of hands.

Historically it was pretty popular; SUSE may have even been the second most popular distro worldwide at one point...but, these days? Not so much.
Presumably sldcool is objecting to using this tragedy to make a political point so soon.
Not hackerly, not notable, not cogent.

No thanks. Flagged.
That sounds like a lot of work and a lot of pain (and likely bugs) just to end up not quite back at square one thanks to the resulting performance drop. I feel what you've done here is the rough equivalent of pointing out that "nothing is stopping you" from building a webpage generator in brainfuck. It's turning complete after all! You could add whatever logic is necessary, like UTF8, XML, and Json parsing, etc.

Technically correct, but fails to address the core point that this might be a terrible idea.
Could you elaborate on how these points not apply to the IEEE standard for decimal floating-point? From what I can grasp, also the IEEE standard has multiple representations for the same values.

> For most comparisons (no, comparing numbers with the same exponent is not the norm)

I'd say that exponent 0 is the norm, meaning precise numbers in a really wide range, isn't it?
The superman penny shaving attack is not related to rounding behavior. You may multiply with fractional values, but when you add or subtract from a ledger, you are doing so in fixed precision (usually cents). If you were calculating something like interest and consistently rounding in one direction, you'd be either over or undercharging people, but the money wouldn't vanish.

In other cases, you need to actually think about rounding mode (e.g. how many shares of AAPL can I buy with $5000).

> there's no problem statement on his entire website to address what actual problem he was trying to solve

This is very true. I don't understand what problem this is trying to solve, because I don't spend a lot of time confused by the internal detail that a double is binary. The storage format isn't important beyond knowing roughly how many digits of accuracy I can count on.
There's a magnificent video available of flying in a U-2, featuring James May of Top Gear fame as passenger: https://www.youtube.com/watch?v=1PmYItnlY5M
the cards power up the pawns in this game so advancing two squares to speed up the game is unnecessary (it gets hectic pretty quickly)
> There are also 255 representations of almost all representable numbers.

Of course ... That's true of any decimal number representation with an exponent. Why is it a problem?
a) "Plane loses power" isn't that simple. There are multiple different independent "power" systems for different things, each with their own redundancies. Particularly critical systems, like engines, often don't need anything else in the aircraft to be functional to continue to work. Power failures, even fairly catastrophic ones, are trained for and there are checklists for such events. (This goes all the way to the point of losing power so badly that you have no instruments and no radios, there are procedures for using a very simple battery-powered radio transponder to alert ATC of this fact, who can flash high-powered light beacons at you to give you landing instructions when you get close.)

b) Ignoring the "power failure" question, decompression at altitude is also a known danger with its own procedures. At FL350 (35,000 feet), you'd have 30 - 60 seconds of "useful consciousness"[1]. Aircrews can don oxygen masks in much less time than that; this is trained for. Further, continuous use of oxygen masks by at least one pilot is mandatory when flying over at an altitude greater than FL410 with multiple pilots, or above FL350 with a single pilot. Again, if things fail so catastrophically that aircraft-supplied oxygen doesn't work, there are small standalone oxygen tanks on hand to provide at least 10 minutes of air, which is more than enough time to make an emergency descent to a breathable altitude.

Also, to the premise of the question, cabin pressure should never be lost in response to an electrical failure; these things are designed to fail "safe". There are mechanical components that have to be actively thrown for decompression, which can be done by hand if electricity is unavailable and won't be triggered during a loss of power. Uncontrolled decompression is usually the result of a structural failure (seal or gasket failure; metal structural failure; etc).

[1] http://en.wikipedia.org/wiki/Time_of_useful_consciousness
The Colosseum in Rome still exist

The Colosseum (and much Roman construction) was built with stone but also concrete. The composition of Roman concrete is such that it's much more durable than most modern concrete, due in part to material properties not well understood until recently.

There's also a survivor bias built into structures which have survived the test of time: by definition, what's lasted are the structures which have lasted.
> There are 255 possible representations of zero. They are all considered to be equal.

And we're done here folks.
You find Luddites in every field. Not using DNA is like sorting millions with bubble sort because that's the way you learned to sort in 1st grade.
I'm taking a 4 day long Linux foundation course starting on Monday called "Linux performance tuning". Looks like it is going to be interesting.
Might I suggest a glider rating? My opinion, and yours of course may vary, is that it's vastly more interesting and exciting.

There's nothing quite like pounding along at ridgetop level, two hundred feet off the trees, going 120kts with everything bouncing around the cockpit. Or sitting in perfectly still air at 12,000ft, climbing effortlessly, watching airliners wander through below.
What you wrote underscores how the patent process is flawed. IBM abused the spirit of patents for their own financial gain.
The announcements that came out at F8 three years ago were pretty big. I thought they didn't do another one because they had nothing else to promote to developers. Wondering what's cooking this time.
That's an excellent point. However, I don't think it accounts for all of it. There are lots of cases where people can panic and still survive. It lowers the odds, but doesn't reduce them to zero.
And the building isn't necessarily in an office park.
Thanks! Looking into it!
Bitcoin wallets are surprisingly tricky to implement. Use a good one that a lot of others are using, not the edgy one. Don't try to customize your key pair, just use what's generated for you. Split the wallet you spend from from the one that has real money on it. Backup the real one with a paper wallet and keep that safe.
>You might want to consider putting a banner on the site: "Hacker News for Bitcoin".

That is a great idea.

I had been toying with the idea of some kind of banner for the last few days, either relating to a crypto-contest or karma-contest, but was worried it might detract from the "HN Look" which I had worked so hard to achieve.

Thinking it over now it looks like more of a necessity than a distraction.
There are actually undercover stings going on too, by the looks of things http://www.reddit.com/r/SXSW/comments/1zwr26/atx_welcome_to_...
That is not the case – there is exactly one representation for every single IEEE 754 value besides NaN – and checking if something is NaN or not is easy (two instructions). Not only that, but negative and positive values are in integer order, meaning that you can compare same-signed values using integer comparisons.

What I meant by exponent zero not being the norm is that most numbers you work with won't have exponent zero. Specifically only one in 2^16 of the possibly representable values and only one in 2^24 of the possible representations. If you're using the "natural" representation, then only the integers -9 through 9 have zero exponent.
it looks beautiful but just having the page open on my 2011 Macbook Air results in about 50% constant cpu usage, fans spinnig up etc without me doing anything. Thats a bit much.
Ask HN: Living in a hacker house... Is it worth it?
Im currently living in a hacker house where people have their own seperate bedrooms.

Its great for networking, parties and meeting cool people etc, but the place is not being maintained

http://tiny.cc/hackerhousefuntimes

After living somewhere for a while, it's hard to maintain perspective. If you had a choice to live in poorly maintained living conditions but with cool people, vs living on your own in a studio, what would you choose? Does anyone know of hacker houses in SF that have decent living conditions (preferably with seperate bedrooms)?
I think they just decided to go with the distributions that have a commercial backing behind them (or, at least, their "free" versions). But I agree that Debian should be on that list.

P.s. happy openSUSE user here :)
Eliminate the temporary file:

sed -e "s/./x/g" < list.txt | paste - list.txt | sort | cut -f 2
OK. It looks like the proposed representation represents numbers as a signed 56 bit integer times ten to a signed 8-bit number. That does avoid fiddling with BCD, but it's VERY different from usual floating point. Look at the neighborhood of zero. As with usual floating point there's a gap between zero and the smallest nonzero number... but unlike floating point numbers, the next larger nonzero number is twice the smallest nonzero number. The behavior of numerical methods in DEC64 will, I suspect, be quite different from that of floating point. It would be very interesting to know what the difference is, and I'd hope that proponents of it as "the only number type in the next generation of application programming languages" would exercise due diligence in that and other regards.
The rules look like a mix of many special cases. Can this be implemented as currying? http://en.wikipedia.org/wiki/Currying
UX Design Tips
Online Education should be inspired by Video Games
Agreed. I'd rather see an aviation story than one on yet another Twitter clone.
All I see is what appears to be some weirdly colored landscape. There is no text or anything to explain what I am looking at, and there do not appear to be any interactive elements on the page or any time-varying content.

Does the site esquire a plugin or something? If so, the author should at least put something there in HTML to explain what is required.
Re: 2, whether or not this is true, it doesn't seem to have anything to do with the protocol on its own.
That's why you need an entrepreneur that has both skills (biz & tech). Engineering chops to execute (code) their dreams and business sense to make sure that they are building something that creates value for customers and not a hobby.
The Thrilling Physics of Resonance
Great! I've always been self-taught with Linux, so I'm sure I do a number of things in a suboptimal way, and this seems like a great way to clear some of those bad habits away.
The reason that SEP are worth less (than other valid patents) and not entitled to injunctions

Actually, almost no patents are entitled to injunctions since the eBay decision made courts apply the same standard to patent cases as to other injunction requests, and we all owe many thanks to the Supreme Court for that.

some SEPs are pretty low grade too

Indeed, the Microsoft v. Motorola patents were particularly lousy. One Motorola patent was on the use of a particular number as a key in an error correcting code. The code itself was prior art but any two devices needed to use the some identical arbitrary key to communicate. It's embarrassing that the PTO allowed that one, but the court is making Microsoft pay for every device shipped now. Fortunately the price is small.

The Apple v. Samsung case involved a few Samsung radio channel efficiency patents that the jury found not infringed even though Apple did infringe them. They were probably as invalid as all the utility patents in the case but they failed to be useful probably because they were complicated and juries don't pay much attention to technological patents or discussions of them.

Apple's garbage patent about bounce-back was much more effective. Juries can measure that.

Now SEP (standards essential) patents are much less useful because judges are not inclined to allow them to be used defensively. And arguably valid patents are slightly more powerful than clearly erroneous ones. But simple garbage patents focused on non-technological UI and superficial means of doing business are much more effective in all litigation than actual technological patents independent of SEP status or validity.
Thanks for the offer... thankfully some of my friends are french-fluent as well as the bulk of my family, so I can get help if I need something specific translated. I just haven't gotten around to it yet. If you're personally interested the site is available at

http://tiplanet.org/
"Excellent communication skills and the ability to work well with others"

The author added this in the rewrite, but I think this is exactly the kind of filler that needs to be avoided. These things are mandatory for basically all jobs, and people who can't communicate and work with others don't think they lack these skills anyway.
I don't know anything about ripple, but that's true of everything ever made. He'll, I've made my own currency and have all the coins. Trading them for real stuff is kind of hard, though.
Curious, why do you have rbenv and ruby-build deprecated?

Edit: Nevermind, it looks like chruby and ruby-install are the new black.
Ugh. Apple can go to hell. I use F.lux as my main point about the problems with Apple's walled garden. It's available GRATIS for iOS but Apple censors it so you have to jailbreak. The idea that Apple works to thwart this means they are actively hurting people. This specific issue was step one on my long journey to GNU/Linux and leaving Apple and proprietary software behind. Yes, F.lux (Redshift for me now on Linux) is that valuable in my opinion.