A thorough evaluation of Go from a Google Employee - <AUTHOR> http://scienceblogs.com/goodmath/2009/11/googles_new_language_go.php

<comment><USER2> I'm interested in the independent opinions. I hope to see more of them going forward.

Here is my relatively uninformed opinion based on having read through their examples and some of the recent discussion.

Having looked at the language a little, I think I understand why they don't have exceptions yet (if ever). The problem is that they envision using this to write servers, and the servers will essentially use a microkernel design with message passing through channels. But when one of your little miniservers goes down, who is it supposed to report the error to and how will that be dealt with? If there is no good answer, then what sense does it make to let a miniserver go down without warning?

To be concrete, take this example from the documentation:

      func startServer(op binOp) (service chan *request, quit chan bool) {
          service = make(chan *request);
          quit = make(chan bool);
          go server(op, service, quit);
          return service, quit;
      }

If an exception is thrown within the server function, who catches it? What can startServer do? Someone who talked to chan? The last process who tried to talk to chan? Everyone who tries to talk to chan? Do we shut down the whole program? Concurrency gives you tangled flow of controls, and you don't have a simple stack where it is clear who has responsibility for a given error. In some ways it really _does_ make sense for the server to pass back an error object somewhere and let someone else figure out what to do about it.

Moving on, I think a better mental model for "interface" is "implicitly matched mixin". Like a Ruby mixin and unlike a Java interface, once you've matched the set of methods in the interface you can now call the methods that are appropriate for that interface. That's very powerful, and potentially very dangerous. When you write a larger system I could definitely see method name collisions becoming a big deal.

Moving on, the lack of generics is huge, and I hope they solve it. They have first class functions and closures, but when asked on the mailing list whether they support standard functional goodness like map and reduce, the response was that the type system made that really hard. When I think about it, I can understand why they are fighting the type system. But if they can add generics then they can solve that problem. The challenge is doing it efficiently.

And my final thought is that anyone thinking of building a real server out of this should read up on capability systems before figuring out their security/permissions model. I say this because having a channel to a service IS a capability, but most programmers don't realize how powerful that organizational concept can be. If you think that you're among them, <http://www.eros-os.org/essays/capintro.html> provides a good introduction.

<comment><USER3> "But when one of your little miniservers goes down, who is it supposed to report the error to and how will that be dealt with? If there is no good answer, then what sense does it make to let a miniserver go down without warning?"

Answer: [http://www.erlang.org/doc/design_principles/des_princ.html#1...](http://www.erlang.org/doc/design_principles/des_princ.html#1.1) . You send the error to the supervisor.

Go strikes me as less C++ meets Python than C meets Erlang, but Go has the C side covered better than the Erlang side so far. If Go "steals" the OTP framework, and especially if channels grow the ability to span across different nodes, Google will definitely have something interesting (to me).

<comment><USER4> > if channels grow the ability to span across different nodes

This is being considered, rob said he has been thinking a lot about it, but obviously they want to get something as important _right_.

<comment><USER3> Absolutely, by all means, take the time to get it right.

I don't know if I'm saying something blindingly obvious or not, but it still should be said just in case: The team really needs someone who has not just glanced at Erlang tutorials, but actually used it for significant work. Not necessarily "hired", but certainly in the loop. The Erlang community could tell you a lot about what works, and give you a few things that don't work in Erlang well either.

OTP is killer for reliable server apps, but it's really hard to understand the full implications until you've used it yourself for a while. Implementing cheap threads is great, but there's a couple more primitives to grab that make it truly powerful.

I am advocating this because as much as I like Erlang, I'd really love to see another language steal its thunder. The syntax and performance are dubious (not terrible, but not stellar). But while I've seen other languages implement bits and pieces of the whole, I'm yet to see another community grok the totality of the Erlang platform and correctly port it into their language, often because they're trying to graft something into their language that it just can't support. Go is probably not in that position, and is my best hope for this sort of thing.

</comment></comment></comment></comment><comment><USER5> This is a good review of the language from someone who has had a chance to work with it, and is inside Google. He shows some quite nice examples of its use, and reports that it is exceedingly fast to compile and generates good code.

(This is the _Good Math, Bad Math_ blog)

<comment><USER6> Next up, a thorough evaluation of Visual Basic from a Microsoft employee.

Doesn't quite have the same ring to it, does it?

<comment><USER7> But, how much work does Microsoft really do with Visual Basic? Given the press, I have a feeling that Google might want to start actually using this for production work.

</comment></comment></comment><comment><USER8> Something that strikes me about the language is that it was clearly designed by systems programmers as a replacement for C - but not a replacement for C++. The ability to return and concisely accept multiple values from a function simplifies procedural error checking considerably - exactly the kind of error checking that is all over systems code.

</comment><comment><USER9> > Interface types are similar to interface types in languages like Java, with > one huge exception: you don't need to declare what interface types you > implement!

Nice. This seems to add the benefits of duck-typing, but with type checking.

</comment><comment><USER10> This is one of the more thoughtful evaluations I've seen. All too often, a language evaluator mistakes their misunderstanding of the design for a design flaw. Evaluating a new language is often the tricky mental task of understanding a different way of thinking. This reviewer gets it!

</comment><comment><USER11> So does it have closures?

<comment><USER2> Yes it does. It has full first class functions and closures. However the lack of generics means that you can't write a general-purpose map, filter, reduce, etc. You'll need to keep writing almost identical pieces of code.

See <http://golang.org/doc/go_spec.html#Function_literals> for confirmation and [http://groups.google.com/group/golang- nuts/browse_thread/thr...](http://groups.google.com/group/golang- nuts/browse_thread/thread/74a37a9923cdf327) for more details.

<comment><USER12> _However the lack of generics means that you can't write a general-purpose map, filter, reduce, etc._

I'm not so sure, why not just define them "dynamically"? From the article: _it's defined as an empty interface, and everything implements the empty interface_

<comment><USER2> Well if you follow the second link you will find Adam Langley (one of the initial developers of Go) saying that the type system precludes a generic map, grep, etc.

You point out that everything implements the empty interface, but knowing that something implements the empty interface isn't very useful. A map, grep, etc needs to be passed a function and a bunch of data, then needs to apply the function to each piece of data. But the type system can't let you pass a piece of data to the function unless it knows the types are compatible. So if your function takes ints and adds them, then you really need to know that all of your pieces of data are ints. To use functions that accept data of other types, you will need a different version of grep for every type of function you accept.

This is exactly the problem that generics tries to solve.

</comment></comment></comment></comment><comment><USER13> MarkCC has also written some wonderful poignant work on bullying and how it affected his life. One of the few blog posts that's really ever moved me.

</comment><comment><USER14> I've seen a lot of good analysis of Go, and I hope its creators carefully consider it and work to make Go (if they keep the name) even better.

</comment><comment><USER15> Oh, man, that new pointer syntax is going to trip up a lot of C/C++ programmers...

</comment><comment><USER4> It is a pity that he doesn't say anything about the awesome CSP-based concurrency system, which is one of the greatest features of the language.

That aside, it is a very good read (although I think his complaints are a bit silly, iota might look a bit strange, but works really well, and it is very simple, anyone can understand how it works in 30 seconds).

</comment><comment><USER16> Articles that label this language 'go' instead of 'i9' or 'issue9' should be ignored.

Stand up for the little guy and help a bit, with every article that cements 'go' as the new 'go!' there is more damage.

Already you have to look real hard in google to find anything on the 'old' go. It really isn't fair.

When you're a giant you should tread carefully, lest you flatten someone by accident.

EDIT: hey downmodders, if you disagree, let me know why.

What would you think if google decided to call their project 37signals or something like that next week ?

Would you stand by 37signals or would you tell them that on that scale their efforts amounted to nothing anyway so they should man up and change their name ?

What rationale do you have for giving google a free pass on this ?

<comment><USER17> I have a couple issues with what you're saying.

First, there's a long history of name appropriation about which I'm quite certain you've never raised any concerns. For example: this site's domain name, which represents the appropriation of an important bit of CS terminology by a for-profit concern which isn't in any way related to that bit of terminology. Where is your outrage toward PG?

And I'm glad you chose 37Signals as an example further on in your post, because they recently launched a search-oriented (helping designers and clients find each other) service named "Haystack". A friend of mine was already maintaining a somewhat-popular (in its niche) search framework for Python web apps called... Haystack. Guess how many people are standing up and denouncing 37Signals as the Big Bad Evil Destroyer? You didn't, so far as I'm aware.

So it seems somewhat hypocritical, or at the very least arbitrary, to single out Google for the treatment you're advocating while overlooking numerous other examples of the same thing happening.

And this leads into my second concern: I don't really see how someone can stake a permanent claim to a name in a field based on not much more than a niche/hobby project. If "Go!" had been more heavily marketed or more widely disseminated (or even maintained; it seems to have basically died as a project), I'd be more inclined to sympathy, but the simple fact is that it wasn't: until the past couple of days, it had spent its entire existence shrouded in obscurity, and to my mind that's nowhere near enough to begin dictating the use of the name to anyone.

<comment><USER16> Y combinator was as far as I know not in use for the domain of 'start-up booster / mentors / incubators'

And I wasn't aware of the 37signals name clash with respect to 'haystack', and I really wonder how you can expect me to be supportive of things that I am not even aware of.

But, now that you have raised my awareness to the issue, if the clash is for the same problem domain, then yes, I think that 37signals should change their name.</comment></comment></comment>


Introducing Amazon Fresh - <AUTHOR> http://fresh.amazon.com/MembershipBenefits <comment><USER3> Amazon Fresh isn't new -- it's been around in Seattle since 2007. What appears to be new is the Prime Fresh offering as a new gating mechanism for it: $299 per annum (effectively $220 if you're already a Prime customer), which also cuts away the delivery cost.

At first blush, I'm not sure if the value proposition is attractive enough for me, even though I'm more or less the target demographic (upper-middle-class, 20's, who lives alone, without car). $200/year is not an insignificant amount of money: I can get a ZipCar for an hour for $10, and hop over to the Trader Joe's at Capitol Hill and get cheaper, higher quality food.

The big thing here is the time savings (which is valid: ordering off of Fresh is just as easy as ordering off of Amazon itself).

<comment><USER4> Back of the napkin calculations put the cost of Prime Fresh at less than the cost of Zipcar grocery shopping.

Realistically, you can't drive to the grocery store, do your shopping, drive home, unload the car, and drive the Zipcar back to its parking spot in anything less than two hours. (And maybe fill it up with gas, if you're unlucky.) Even with a cheap Zipcar, that's $16 + tax per trip.

$220/$17 puts the equivalency at 13 trips a year. So, Prime is cheaper if you grocery shop more than about once a month. I certainly do.

If they bring this to Boston, I'm in.

<comment><USER5> I saw ads for stop & shop's "peapod" service on the T: [http://www.peapod.com/](http://www.peapod.com/) .

Haven't used them myself though.

(and the ad said that you can use T2013 as a coupon code and get ?15$? off your first order)

<comment><USER6> My experience with Peapod is a few years back when I had a broken foot and was on crutches. It was great for me in those circumstances. I could order from a (somewhat limited) set of things and they would (mostly) arrive at the scheduled time. Going to the store to pick up the odd item wasn't that big a deal but doing a full grocery shopping was difficult.

Now, if I could reliably do a full grocery shopping with all the ordered items delivered from a good selection I might be tempted. But probably wouldn't pay the necessary fee as the grocery store is 4 miles down the road from my house and I have a car. (Also I imagine I'm too far out of the city to get the service anyway.)

</comment></comment></comment></comment><comment><USER7> Grocery delivery in the UK is amazing! I wish it was like this everywhere. All the major chains have professional websites, nice trucks, cheap service. Delivery prices range from about £3.00 to £6.00 depending on the time of day.

Sadly, I'm moving to Canada where grocery delivery is nearly non existent. I hope amazon solves my problems there.

<comment><USER8> Yeah, when I lived in the UK I often used major chain's delivery services (Tesco, Sainsburys, Ocado, etc) when I couldn't get to a store. Safeway has a pretty good delivery service in the US for next day grocery deliveries (pretty much as good as in the UK - apart from the website, which is pretty terrible).

Though, one of the perks of living in the Bay Area is Instacart. Instacart is 100x better than the UK delivery services since they offer same day delivery that generally arrives within 2 hours (and then there's Postmates if you need things within 1 hour). They also have a subscription model like Amazon Prime Fresh where if you pay $99 a year you get free delivery for orders over $35 which is super useful.

</comment></comment><comment><USER9> Already have Prime. No way I'm paying another $220/yr. Another $80/yr would be pushing it. But my neighbors in LA certainly do seem to be adopting it quickly, and it's helping me because a Fresh truck delivered one of my packages recently.

</comment><comment><USER10> I experimented with a few options here in SF for groceries. I tried Instacart; it works out to be slightly more expensive than be taking an uber back and forth to the closest TJs and buying stuff. The best of the bunch now appears to Walmart to go[1]. They have a minimum delivery of $35 but stuff appears to be reasonable (assuming you don't have personal objections to walmart). The site is kind of shitty though.

I would probably go the Amazon route if they released fresh here and made it cheaper to get a membership. I use Amazon for almost everything else.

[1] [http://delivery.walmart.com/](http://delivery.walmart.com/)

</comment><comment><USER11> I cannot wait for this to launch in San Francisco.

Depending on your location in the city, grocery shopping without a car can be a pain if you're buying enough food/organic produce/grass-fed meat for 21 meals/week x 2 people.

Add the cost of ~1.0-1.5 hours of a ZipCar on top of the 'organic premium' and a delivery service makes sense.

In NYC, FreshDirect was worth the delivery cost. They charged per delivery rather than a subscription. Their food quality, variety, consistency, time- savings, and organic options always exceeded my expectations and made it worthwhile.

I'll pay the fee on top of my Prime membership for this in San Francisco.

<comment><USER12> You may wanna try Good Eggs: [http://www.goodeggs.com/welcome](http://www.goodeggs.com/welcome)

</comment></comment><comment><USER13> I used the free trial in LA for a while. I placed quite a few orders in the two months that I used it, but ultimately decided to cancel it before I had to pay the additional $220.

The selection was somewhat mediocre compared to what you would find in a real grocery store. The quality of produce was good, while the quality of the meat was mediocre. The selection of wine and beer was abysmal (wine and beer were made available through a third party, but they seemed to have a very limited selection). The pricing was also considerably higher than what you would find at a supermarket and just slightly lower than Whole Foods (while the quality was not nearly as good...). They seemed unable to meet the demand for certain items (La Brea bakery bread for example), and in two separate orders they just didn't send some items.

I realized with the first order that you really need to do the in person delivery since you'll be stuck with a bunch of giant box/bag things full of frozen water bottles cluttering up your residence unless you return them to the delivery person. They encourage you to tip the delivery person as well, which I find annoying. If I'm already paying $220 for this additional service, why don't Amazon pay them a decent wage? In the end, I just don't order enough groceries to justify the $220 a year it costs.

</comment><comment><USER14> How does Amazon Fresh compare to Webvan of old? For me, Webvan was kind of cool (I still have a green plastic box), but it was kind of a pain in the ass. The main points against it, in my book, were:

\- It's hard to keep track of recurring purchases. If I haven't finished something, I don't (necessarily) want more of it piling up. That, and I'm lazy and will get annoyed if this is happening with more than a couple of items. \- Deliveries had to be scheduled days in advance. Often I just need a couple of things to finish a meal, and I'd rather buy those and have them delivered in an hour. When I make a grocery list, it's often just-in-time when I go to the supermarket. I know what I'm missing _right now_. It's a lot more difficult to predict what will be missing 3-4 days from now. \- The interface for finding things was a pain in the ass. Presumably Amazon can fix this, but their interface isn't exactly stellar. It's easy to find a three-four things relatively quickly, but the loiter time I spend on each product is probably 5-10 minutes because of comparison shopping. This isn't how I approach buying things at a supermarket where I usually know the location of something because it's always in the same spot.

</comment><comment><USER15> We've been using fresh in Seattle for a couple years. They've always had free delivery with a minimum order (it's crept up to about $100). The big "secret" is that they will deliver many prime-eligible amazon.com items. So it's pretty easy to hit the minimum if you throw in a couple of books or a hard drive.

</comment><comment><USER16> Well, this isn't in my area, but I'd be all over it. First off, I live in a city center, and I'm single. I walk to the grocery store and carry everything I buy, so I typically go twice a week and spend about $50 each time. It takes about 45min to walk to the store, shop, walk back, and unload groceries.

If this is $300/yr, that means I have to decide between going to the store myself, or paying $2.88 for amazon to deliver my groceries every few days. $2.88 to avoid putting on pants, interrupting my workflow, walking to and from the store, and waiting in line. That seems like a deal I'd take.

Then again, when I go to the grocery store, I usually walk to the bakery, market, etc. Plus, being forced to leave the house, wear pants, and interact with human beings has some advantages. Sometimes I get too comfortable being at home, and the fear of starvation is good motivation to get fresh air.

</comment><comment><USER17> $300 a year for the privilege of being able to shop with them? And there's still a $35 minimum order for 'free' delivery? WTF.

This has got to be the worst value prop I've ever seen -- online grocery delivery services are way cheaper than that, even if you make a shitload of orders. The one I use costs $7 a run for under $100 or $3 for over $100. Even if you make an order every other week that's under $100, you're still at just over half the price Amazon is charging.

</comment><comment><USER18> This was around already. The relevant news story is that this service may be announced for San Francisco next week: [http://allthingsd.com/20131205/online- retail-giants-grocery-...](http://allthingsd.com/20131205/online-retail- giants-grocery-delivery-service-amazonfresh-may-launch-in-san-francisco-next- week/)

</comment><comment><USER19> Grocery delivery is fantastic when you need it, even if it costs a little more than driving out and doing it yourself.

In the Twin Cities area we have Coborns Delivers ([http://www.cobornsdelivers.com](http://www.cobornsdelivers.com)). It was amazing to have groceries delivered to my front steps in the winter time after we had a baby.

</comment><comment><USER20> Has anything changed with Fresh recently? Looks about the same to me.

Incidentally, my review of the LA service from a few months ago: [http://tiamat.tsotech.com/amazon-fresh](http://tiamat.tsotech.com/amazon- fresh)

TLDR: It's a welcome and long-anticipated return of home grocery delivery but there is a lot of room for improvement.

<comment><USER21> It seems like they've rolled it out to more of LA. When it first came here my address wasn't eligible, but apparently it is now (although for some reason before it lets me proceed it shows a big warning saying that I'm not in the Seattle delivery area)

</comment></comment><comment><USER22> Just in case you're confused -- as I was, until I started digging through the details:

Amazon Fresh is the store.

Amazon Prime Fresh is the subscription service, a $220 add-on to Amazon Prime (so, basically, you're paying $300 for both Amazon Prime and Amazon Prime Fresh).

Your subscription allows you to shop at the store (Amazon Fresh), and orders over $35 qualify for free shipping.

</comment><comment><USER23> I could stomach the $299 per year if the prices were cheap, however - <USER2> avacado I could find was for $1.29 per avacado.... that's a lot more expensive then the 48c special at sprouts.... especially when you factor in the cost of membership.

</comment><comment><USER24> This would be more attractive if Amazon Fresh weren't completely unreliable-- it's often out of stock of the products I want. I must throw my recipie plan in the trash on a regular basis. Whole Foods or PCC it is most definitely not.

</comment><comment><USER25> Came for world changing technology.

Got vegetables.

</comment><comment><USER26> After reading Brad Stone's book I winner if this is the first shot across the bow against Instacart, PeaPod et al. A race to the bottom

</comment><comment><USER27> Way more excited about this than drones!</comment>


Tesla owner recreates fatal Autopilot crash, nearly crashes as well - <AUTHOR> https://www.cnet.com/roadshow/news/tesla-fatal-crash-autopilot-recreation/ <comment><USER2> Discussion thread when the video was posted here the other day (109 comments): [https://news.ycombinator.com/item?id=16732436](https://news.ycombinator.com/item?id=16732436)

<comment><USER3> I wanted to post same link, the post was gone from first page much faster then other less interesting posts IMO so I am suspecting that maybe Tesla fans are downvoting discussions about this crashes.

In this case someone reproduced the bug, the blinking lights are a timed warning not related to what is on the road.

<comment><USER4> People tend to flag copycat posts about topics that have already been posted/discussed extensively.

It's less about "Telsa fans" and more about "HN fans" who prefer the site to be focused on discussions about new, interesting things rather than repetitive outrage-inducing things.

None of this is to say the topic isn't important, but a topic's importance is separate to how much value there is in discussing it repeatedly here, particularly when it stirs such heated emotions in some people.

<comment><USER3> This video was the first timeThat topic was first time when it appeared, no one commented that it was here before and linked to that page, it was an actual video so not an opinion blog or media spin.

The video was very clear and it showed a real problem, the system followed the wrong line on the roads and the comments were answering explaing what they thing it happened, what the capabilities and limitation of Tesla radar are( I learned that Tesla has a radar) and of course there were the skeptic comments that I think are the cause of those dislikes, I don't think is good for the community to disaprove of well thought skeptic comments, some of the readers here studied AI in universities and worked with AI and know about it's limitations and they can express the skepticism that the self driving hardware and software is not ready yet.

<comment><USER5> But, as has been pointed out above, the video has been posted here, and has been discussed here. There are over 200 comments about the video.

The link you posted contains no new information.

<comment><USER3> You do not understand, I did not post this article, I commented that the posted video was gone suspiciously fast from first page, where other much less interesting topic were one the first page much more time that day, and I was sharing my conclusion(that could be wrong) that some Tesla fans (hopefully not the company PR) was involved

<comment><USER4> If you notice "suspicious" voting activity or stories dropping off the front page faster than you believe is warranted, you should contact the mods via email (email@example.com) rather than speculating in the comments, as the guidelines request [1].

This specific story might have been new, but the broader topic of the safety and functionality of assisted and autonomous driving systems has been extensively discussed over multiple articles in the past couple of weeks, and it's inevitable that members of the community will start to tire of any topic that has had extensive coverage for a sustained period of time.

[1] [https://news.ycombinator.com/newsguidelines.html](https://news.ycombinator.com/newsguidelines.html)

<comment><USER3> It would help to have some data to check my suspicions(I will check if there are some sites that track the stories and the votes patterns but not today ), anyway let's see what happens with the new video that reproduces the bug([https://news.ycombinator.com/item?id=16742391#16742956](https://news.ycombinator.com/item?id=16742391#16742956))... now since this is similar to the other one I can see why won't be that engaging, most of what was said was already said on the first video posting.

Edit: 15 minutes later , all Tesla posts are gone from the first page

<comment><USER2> I don't think there's a huge conspiracy. The Tesla crash had 2 different stories (the official blog post, plus separate news stories), 3 days ago:

[http://archive.is/4uQSR](http://archive.is/4uQSR) (snapshot of /best)

And then yesterday, the Youtube video got 205 upvotes with 109 comments, which is pretty good exposure on the same topic: [https://news.ycombinator.com/item?id=16732436](https://news.ycombinator.com/item?id=16732436)

Yesterday, there was also this side story with NTSB that got 90 upvotes and 98 comments: [https://news.ycombinator.com/item?id=16730286](https://news.ycombinator.com/item?id=16730286)

So Tesla stories today might be getting flagged because users feel they are incremental updates.

<comment><USER3> The first video that got 200 comments, some of the comments were made when the story was on first page, the rest were replies that also happened after the story was gone from the first page(the time coincides with US people starting getting up).

It is just a felling/instinct I have and I don't want us both spend our energy on trying to figure it out, if the community votes in this way then we can't do anything about it, maybe having a page that pulls this kind of topics easy accessible would be interesting,.

</comment></comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER6> Autopilot is following the strong white line to the left, which is what the simple system is designed to do.

It (currently) follows road markings, and/or the car in front. That's it, and that's why you don't leave it unattended - spoken as a Model X owner.

As a Brit, I'm astounded at the US road design. You'd never see something like that over here, and I've never seen motorway (freeway) lane markers so worn away.

Autopilot did what it is designed to do, which in this case was the wrong thing. The driver was not paying attention, which is easy to do when you have no physical buttons in the car and often operate a touchscreen. The poor state of the road also contributed, both with the lack of steel barrier and the worn-out markings.

Will road markings be kept in better condition for the sake of self-driving cars, I wonder?

Would LIDAR have helped, or would the presented surface area of the concrete block be too small to act upon?

<comment><USER3> What will happen if it stars snowing? The self driving cars will be stuck on the roads?(I mean in the future where the passenger can't drive the car back home)

Following the line is too basic for a self driving car, I remember some students having small toys programmed to drive toy roads by following the lines, and that was more then 10 years ago.

Tesla should have detailed maps of this big roads, so maybe when the maps and what the car detects do not match it should be less confident, the collision detection should be extra sensitive, the driver should be alarmed, the car should slow down, if they have problems on this big roads then they need a new kind of hardware and software to navigate any medium road.

<comment><USER6> > Tesla should have detailed maps of this big roads

Their imminent software update adds exactly that. They took their navigation data in house because the atuff they used before wasn't detailed enough.

<comment><USER3> I mean the maps data they collect from the other Tesla cars and not the GPS navigation, they said that in that accident a big number of Tesla cars pass that point daily and they also collected this navigation data for training, so I assumed they have this detailed maps and the car should know what to expect(I am sure this is a hard problem ) but maybe they need to be more cautious when there is a mismatch(like if 2000 cars used this side of the road but now it appears some line appeared that does not match, lets safely slow down and ask the driver to take over and analyze what is wrong)

</comment></comment></comment></comment><comment><USER7> This article is about old video, already discussed here in detail. I thought it could be about a new one.

So, couple of hours ago another video surfaced on /r/teslamotors, filmed at original location of Model X crash, with very detailed slow-motion.

And autopilot acts (presumably) the same way as on Model X, trying to drive the car into solid obstacle.

Video: [https://youtu.be/VVJSjeHDvfY](https://youtu.be/VVJSjeHDvfY) Thread: [https://www.reddit.com/r/teslamotors/comments/899i1w/my_mode...](https://www.reddit.com/r/teslamotors/comments/899i1w/my_model_s_failing_in_autopilot_where_the_model_x/)

</comment><comment><USER6> I'm danged if I'd let it get so close to disaster if I was recreating this. One tug of the steering wheel in the wrong direction is enough for me to assert myself and get the car to cancel Autopilot.

</comment><comment><USER8> Can you mount the camera properly and repeat this experiment?</comment>


Amazon files suit against 1,000 Fiverr users over fake product reviews - <AUTHOR> http://www.geekwire.com/2015/after-conducting-undercover-sting-amazon-files-suit-against-1000-fiverr-users-over-fake-product-reviews/ <comment><USER2> Good news.

The non-fiction kindle books are a mess with all of the fake reviews.

        Amazon is not suing Fiverr.
        The company noted in the court filing that these kinds of
        services are banned by Fiverr's terms and conditions and
        Fiverr has tried to cut down on the practice.

Fiverr must not be trying too hard, the first result for the search "reviews" is for "AMAZ'N REVIEWS - I will review your book including erotica" followed by a page full of "I will provide a verified kindle review for you" providers. [0]

        As in the previous lawsuit, Amazon alleges that these
        reviewers often arranged to have empty boxes shipped to
        them in order to make it look like they had purchased the
        products.

They should also sue (ar at least ban/suspend) the marketplace sellers who shipped empty boxes so the fake reviews would have a "Verified Purchase" qualifier, that's something I look for to determine if a review seems legit.

[0] [https://www.fiverr.com/search/gigs?utf8=%E2%9C%93&search_in=...](https://www.fiverr.com/search/gigs?utf8=%E2%9C%93&search_in=category&source=guest- hp&locale=en&query=reviews&category=2&sub_category=181&page=1&layout=auto)

</comment><comment><USER3> >Amazon is bringing this action to protect its customers from this misconduct, by stopping defendants and uprooting the ecosystem in which they participate," Amazon wrote in the court filing. "Although Amazon has successfully requested removal of similar listings from Fiverr in the past, the removal of individual listings does not address the root cause of the issue or serve as a sufficient deterrent to the bad actors engaged in creating and purchasing fraudulent product reviews."

Good job Amazon. As an avid shopper on the site who relies on reviews to make a decision, this is excellent.

</comment><comment><AUTHOR> Hopefully this will start a trend and other sites like Yelp will improve its comment quality too</comment>


Moving to GitLab - sahin-boydas https://mail.haskell.org/pipermail/ghc-devs/2018-December/016613.html <comment><USER2> Note: this is about moving from Phabricator to GitLab, not GitHub to GitLab.

GHC Discussion from November about moving to GitLab/moving away from Phabricator: [https://mail.haskell.org/pipermail/ghc- devs/2018-November/01...](https://mail.haskell.org/pipermail/ghc- devs/2018-November/016457.html)

<comment><USER3> Does anyone know what did not work out with phabricator?

<comment><USER4> Ben Gamari's October 30 email ([https://mail.haskell.org/pipermail/ghc- devs/2018-October/016...](https://mail.haskell.org/pipermail/ghc- devs/2018-October/016425.html)) to the ghc-devs list proposed considering alternatives to Phabricator and outlines reasons that Phab wasn't working.

A summary of the problems outlined in the email:

* Lack of options for support from Phacility

* Free/open source components of Phabricator feeling half-finished because Phacility has redirected development resources to paid features

* Issues with Harbormaster (Phabricator's half-baked CI system)

* Developer's prefer using regular Git to Phabricator's nonstandard workflow, which requires installation of the Arcanist command-line tool (written in PHP to manage patches.

<comment><USER5> > Phabricator's nonstandard workflow, which requires installation of the > Arcanist command-line tool

I was just going to eval Phab for my team, your comment identified a deal breaker for us and you've saved me more than a few wasted hours. Thank you

<comment><USER6> Please ignore the others in this thread.

Phabricator is basically cancer.

I'm partial to Gerrit if you're looking for a git native solution with branch, draft, patch, review, iterate workflows with proper merge/rebase handling.

It is a bit different from "GitHub flow" but mostly a big improvement in an organisation context (vs FOSS.)

Media wiki has the best docs but it's a bit dense.

[https://mediawiki.org/wiki/Gerrit](https://mediawiki.org/wiki/Gerrit)

This page below has a decent graphic and lots of quick examples to show you how powerful it is to work with git instead of gimping it with a wrapper.

[https://mediawiki.org/wiki/Special:MyLanguage/Gerrit/Advance...](https://mediawiki.org/wiki/Special:MyLanguage/Gerrit/Advanced_usage)

<comment><USER7> > Phabricator is basically cancer.

I think you need a lessen in sensible writing. You don't like Phabricator, fine. It's not cancer. Not "basically" either.

<comment><USER6> You don't like my casual use of the word cancer? Fine. Personally I feel like cancer was a relatively good approximation for the cancerous like changes you need to make to established industry workflows once you begin to use phabricator.

Would you have preferred I used the word infection? Virus? Aids?

Which one of those metaphors crosses the "sense writing" line for you?

Why does cancer?

<comment><USER8> Describing software as "cancer" is something I'd expect to see on 4chan or reddit, not HN. It's hyperbole and your explanation ("relatively good approximation for the cancerous like changes [to] workflows") shows as much.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER9> Notably Drupal is also moving to GitLab. It's over 40 000 projects, it's not easy. Announcement was at [https://www.drupal.org/drupalorg/blog/developer- tools-initia...](https://www.drupal.org/drupalorg/blog/developer-tools- initiative-part-5-gitlab-partnership)

And it's coming [https://groups.google.com/a/association.drupal.org/forum/#!t...](https://groups.google.com/a/association.drupal.org/forum/#!topic/changes/ZTYUEParS5U)

</comment><comment><USER10> Gitlab seems to fit all the Open Source Project ideals and philosophy. They don't want the burden of managing a dozen difference software or services for their development, they want coding, not time messing with Ops. And it has to be Open Source and no lock it. And Gitlab could even host it for you with with out you having the hassle.

Amazon, Google. One of them likely to acquire Gitlab. Strategically speaking both company would be a great fit for Gitlab, the only problem is both company absolutely loathe Ruby and Rails.

Or there could be another slim possibility, Microsoft decide to Open Source Github Core.

<comment><USER11> > _Or there could be another slim possibility, Microsoft decide to Open Source > Github Core_

Or there could be another slim possibility, Microsoft decide to acquire GitLab...

<comment><USER12> Then the Department of Justice will step in and it'll be 2001 all over again

</comment></comment></comment><comment><USER13> TLDR; Why GitLab instead of GitHub? From their discussion group thread:

\- Good multi-platform hosted CI or at least workable integration with other (existing) CI solutions

\- Hosted review tool that we don't have to maintain ourselves (though a little bit less good than Phabricator, allegedly)

\- familiar GitHub-like workflow with no requirement to install extra software locally

\- Reuse of GitHub credentials

\- Realistic path forward for migrating tickets from Trac

CI is becoming Achilles heels for GitHub. Personally I would probably also add lack of fine grained permissions for contributors, inflexible diff, very basic code review tool as well.

<comment><USER14> What is wrong with Travis compared to GL's default CI?

<comment><USER15> Does Travis have native Docker support? Last time I checked you had to manually run docker and add "sudo: true" to your .travis.yml.

<comment> http-teapot I am not exactly sure of your use case but we build our Docker images in Travis without problems. [https://docs.travis- ci.com/user/docker/](https://docs.travis-ci.com/user/docker/)

<comment><USER15> I want to run my build/test commands in a Docker image.

</comment></comment></comment></comment></comment><comment><USER16> Was a move to Gerrit or the email patch workflow ever discussed?

</comment><comment><USER17> I don't recall GHC development ever being on GitHub? Most I can find is a mirror at [https://github.com/ghc/ghc](https://github.com/ghc/ghc).

edit: Title has been changed.

<comment> sahin-boydas thx, fixed the title

</comment></comment><comment><USER18> What's the point of moving from one proprietary service to another? One day GetLab will get acquired by another tech giant, or will stay the same - <AUTHOR> doesn't matter too much, because it's already owned by private company and venture capitalists. They do what they want, and they definitely won't turn down million-dollar acquisition offer.

<comment><USER19> I thought Phabricator was open source?

<comment><USER20> Same with gitlab? (They're self hosting an instance)

<comment><USER21> there are some features in pro version, but yeah its mostly open source

<comment><USER22> Afaik, The Pro version is open source as well, it's just not usable without a key.

<comment><USER23> That's not really possible, and I'm not sure what you mean.

<comment><USER24> They may be referring to this: [https://gitlab.com/gitlab-org/gitlab- ee](https://gitlab.com/gitlab-org/gitlab-ee)

</comment></comment></comment></comment></comment></comment></comment><comment><USER25> A small note: what's the difference between GitLab, GitHub etc? Are they companies with a substantially identical target: making money? Does they offer storage on their own server (or even worse others servers in a chain)?

So why the hell instead of moving from a company to another ANY FOSS dev do not came back to classic ML (mirrored offline in personal maildir) and use hosting, multiple if possible, only as a mean to offer a shared repo? Why not even serve the project via the repo itself like fossil?

There is a world outside the web, on our desktops.

Just as a suggestion: try to disconnect your desktop and look what you can or can't do. If you feel "empty" you are in danger.

<comment><USER26> Classic ML sucks, and gitlab is opensource that can be selfhosted. The world evolved and offers now better environments than 20 years ago. No reason to stay behind.

<comment><USER16> > Classic ML sucks

Could you elaborate on why that is? The git and linux kernel projects have been using this workflow for decades and it works very well for them.

> The world evolved and offers now better environments than 20 years ago.

I think that's largely subjective. I have experience reviewing code via email and via a Github Enterprise instance.

The Github based review requires far more scrolling and makes it difficult to find comments that were made and how they were resolved. Plus, it makes the implicit assumption that a comment was resolved if the line commented on was changed in any way regardless of whether or not the change is related to the comment made. When that happens, it collapses the comment thread and requires that I expand them to find out what I commented on and determine whether it was addressed by going to another tab to read through the entire diff, find the approximate location of the line I commented on and see if it was changed as I expected.

With the email based workflow, my email client has a built in index of all the comments made on a patch set threaded by commit that I can click on and I can quickly find the comments I made and any responses to them (and whether or not I've already read them). I can easily get different versions of the patch set and run a diff between them to see what changed (either on the entire diff or on each individual commit).

> The world evolved and offers now better environments than 20 years ago. No > reason to stay behind.

I believe that if something should be considered an improvement, then it should have all the capabilities of the previous version and introduce new features that were not possible to accomplish in the previous version. It shouldn't make things that were easy to do in the previous version more difficult or impossible to do.

<comment><USER27> Not the GP, but I contribute to the Git project. I think your some of your critique of GitHub Enterprise is correct (although don't you need to also "resolve discussion" if the lines change, or is that just GitLab?), just commenting on the "why not ML" aspect of this.

> With the email based workflow, my email client has a built in index of all > the comments made[...]

The reason for why E-Mail based workflows like those used by Linux and Git didn't win over "just host on Git(Hub|Lab)" is because this requires a lot of setup & technical expertise from your contributors that just using a web UI gives you out of the box.

Right off the bat you need to have been subscribed to the list for a significant amount of time to do what you're describing, or if you're lucky (e.g. in the case of the Git project) use some E-Mail archive[1]. You're already looking at maybe a week of setup time for someone who's never used E-Mail in this way (which applies for most devs these days) just to get to the point you'd get in 10 seconds with a search box on GitHub or GitLab.

Does it pay off in a lot of ways? Sure, but at the cost of losing a lot of potential contributors. It's not a big deal for projects like linux.git or git.git whose contributors are by definition at the tail end of the competency curve when it comes being comfortable with setting up this sort of thing, but good luck running e.g. some popular WordPress plugin this way.

1\. [https://public-inbox.org/git/](https://public-inbox.org/git/)

<comment><USER16> > although don't you need to also "resolve discussion" if the lines change, or > is that just GitLab?

I believe Github recently deployed a feature to do just that, but that hasn't made it over to the enterprise version. In either case, it's something that's been a source of problems for quite a few years.

> Right off the bat you need to have been subscribed to the list for a > significant amount of time to do what you're describing

That's one inherent limitation with email lists. Fortunately, both public- inbox and gmane provide a NNTP gateway to allow for access to list archives with an interface that's, for all practical purposes, identical to email.

As an aside, I've always wondered why open source projects like git and linux never adopted NNTP (not necessarily on usenet) as a primary form of communication (and and email CC contributers of code that you're changing) instead of using an email list.

> this requires a lot of setup & technical expertise from your contributors > [...] You're already looking at maybe a week of setup time

I simply don't see how it requires significant expertise or a week to set up. Using a client like Thunderbird for reading the list (or NNTP gateway) doesn't take that much to set up (other than entering the server information and credentials to send replies). Setting up one's git configuration for using git-send-email (to send patches) is only a one time thing as well and isn't any more complex.

Years ago, ISPs commonly provided help pages that gave the server information to set up your client to access one's email account hosted on the ISP and how to access the NNTP server to get on usenet. You didn't need significant technical expertise to follow the instructions on those pages and many non- technical people successfully configured their clients to receive/send their email and participate on usenet newsgroups.

<comment><USER27> > I simply don't see how it requires significant expertise or a week to set > up[...]

I don't just mean the setup required to send a one-off patch. Obviously setting up some random E-Mail client with IMAP is easy. But the sort of setup required to get anything like feature parity with common operations in GitHub's or GitLab's interface.

E.g. when you open a Pull/Merge request on those sites. It's easy to apply & download the patch series locally to test it. For E-Mail client integration you need something that'll "git am" a range of messages. Likewise with "git push" to your topic branch updating the PR/MR. Sure you can do this all manually with git-format-patch and git-send-email, but having something that works smoothly takes a lot of work.

And nowadays the network effects of that setup don't make sense for most contributors, because so few projects still use E-Mail like this. There's a large long tail of contributors to these projects, e.g. the median for patches in git.git per contributor is 2.

<comment><USER16> > when you open a Pull/Merge request on those sites. It's easy to apply & > download the patch series locally to test it. For E-Mail client integration > you need something that'll "git am" a range of messages.

That's a good point. Like git-am is the inverse of git-format-patch. Unfortunately, no program has been written as the corresponding inverse of git-send-email. If a program like that existed, then one could get feature parity.

At least with Thunderbird, one can highlight the messages one wants to save and save them to multiple files in a folder.

> Likewise with "git push" to your topic branch updating the PR/MR. Sure you > can do this all manually with git-format-patch and git-send-email, but > having something that works smoothly takes a lot of work.

Based on what I've read, people typically rebase their patch series and push up a new set of emails as a reply to the original patch series. In Github/Gitlab, people typically make an incremental commit and push it up.

But, if one wants to maintain a clean commit history for a given feature development branch before it's merged, one will have to rebase and apply those incremental commits to their corresponding base commit. That's trivial if the feature is implemented in a single commit, but a bit more complex if it's multiple commits. The former case has been addressed by Github with their squash before merge feature I believe. The latter case requires manual rebasing (which arguably is more more than just doing it locally before pushing up the next version of the patch set).

<comment><USER25> Hem, notmuch/mu4e offer easy magit integration so you can see, test, patch etc straight from a mail messages... That's the power of a text-centric UI vs a graphical-centric UI.

<comment><USER16> I'll try it out. vim is my main editor, so it will be a bit of a learning curve to get used to emacs :)

As an aside, I have tried out gnus for reading the git mailing list via gmane, but I found it very slow in threading messages (when compared to Thunderbird). I don't know if notmuch/mu4e has the same issue though.</comment></comment></comment></comment></comment></comment></comment></comment></comment>


Robot Locusts - <AUTHOR> http://europe.newsweek.com/mini-robot-locusts-492433 <comment><USER2> We spent so long asking if we _could_ do it, that we never stopped to ask if we _should_.

<comment><USER3> People spend so much time talking about "the singularity" but billions of tiny dumb things seems much more like a danger.

<comment><USER4> The tinier, the worse: [https://en.wikipedia.org/wiki/Grey_goo](https://en.wikipedia.org/wiki/Grey_goo)

<comment><USER5> That's pretty scary. We spend a lot of time talking about AI taking over (like in the Terminator films), but the grey goo scenario seems much more realistic!

<comment><USER6> So, the T-1000 was not an apparatus made of grey goo?</comment></comment></comment></comment></comment>


IE11 Gives Microsoft A Shot At Browser Redemption - <AUTHOR> http://techcrunch.com/2013/06/29/ie11-gives-microsoft-a-shot-at-browser-redemption/

<comment><USER2> Likely the thing that drives me batty the most when it comes to IE is it's compatibility modes. While I understand MS's reasoning for this, it, I feel, is really doing more damage than good.

I have seen my share of tickets where the only thing wrong was the user had forced the site to render as IE 7. Thankfully I was able to use that to push the addition of the correct meta tag to our pages, but really, I have to wonder how many people see sites 'broken' because they clicked compat on.</comment>


The Archaeology of the Stars - <AUTHOR> http://www.nytimes.com/2014/02/11/science/space/the-archaeology-of-the-stars.html

<comment><USER2> Paywalled article. Don't do this.

<comment><USER3> You get a number of free views per month, try deleting your cookies or using a private window.</comment></comment>


Use PuTTY as a superior command shell on Windows - <AUTHOR>

In the past I have installed cygwin and sshd on Windows, so that I can log in to localhost via PuTTY, because I like PuTTY better than the default cygwin shell or rxvt.
I was just setting that up tonight, when I ran into a PuTTY version that does not require sshd to log in to Windows localhost, only cygwin.
http://code.google.com/p/puttycyg/
So far so good. <comment><USER2> Have a look at mintty as well. <http://mintty.googlecode.com>.

</comment><comment><AUTHOR> clickable: <http://code.google.com/p/puttycyg/></comment>


Vuez – A very simple but powerful state management for vuejs projects - <AUTHOR> https://github.com/markselby9/vuez <comment><AUTHOR> Vuez is a very simple state management library for Vue.js projects, with only two APIs. Please kindly check the repo and demo projects if you are interested :)

<comment><USER2> If it meets the guidelines, this might make a good 'Show HN'. Show HN guidelines: [https://news.ycombinator.com/showhn.html](https://news.ycombinator.com/showhn.html)

</comment></comment><comment><USER3> >Whenever you are interested in monitoring an object or an event, start a new column in the table with a new name, with an object you plan to monitor

row?

<comment><AUTHOR> Yes that's roughly the general idea. If you're interested in something named 'foo'(let's say an object), use store.observe('foo', some_object) to observe it, then define some actions on the name 'foo' wherever it's convenient. Next time you call the store.observe('foo', changed_object) somewhere, if the object is changed, the actions would be automatically triggered.</comment></comment>


Show HN: Starting Senior Consulting Marketplace - <AUTHOR> http://devcaptains.com/ <comment><USER2> Interesting. I will probably sign up soon as I'm looking to get into more contract/freelance work and it seems like a better place to get gigs rather than Upwork. A few questions: How many companies are there currently using this? What is the screening process by the panel like?

Just a tip, I would change the background image behind the "Hire a Dev Captain" signup. The white text gets lost on the background of that image.

</comment><comment><AUTHOR> Hi,

This is lean page to test a senior consulting marketplace for tech leadership and development. The concept is a response to consulting and engaging in freelance marketplaces for the last 3 years.

Looking for feedback.

Thanks!</comment>


Reminder - Live Steve Jobs interview at D8 tonight 6pm PST - <AUTHOR> http://d8.allthingsd.com/20100601/steve-jobs-session/

<comment><USER2> FYI, Kara Swisher has said the interview will not be streamed live:

<http://twitter.com/karaswisher/status/15205166069>

<comment><AUTHOR> Ah man, too bad. It says live coverage on the site.</comment></comment>


How to Raise Your Rates with Existing Clients - <AUTHOR> http://glennstovall.com/raise-your-rates/ <comment><USER2> Nice and straightforward post on the necessary business side of freelance work.</comment>


Getting started with linear algebra - <AUTHOR> https://hadrienj.github.io/posts/Deep-Learning-Book-Series-Introduction/ <comment><USER2> But [https://graphicallinearalgebra.net/](https://graphicallinearalgebra.net/) is available for free and uses easier-to-read graphical syntax. Why prefer this book instead?

<comment><USER3> The original linked text is probably better for a linear algebra learner if they want to apply it (especially if they want to apply it earlier rather than later). Your linked text looks (I've read the first 5 parts) to be a good introduction but at a higher level of abstraction (category theory and abstract algebra). In fact, I think it may present a good motivating case for understanding that level of higher abstraction (while it's ostensibly about linear algebra, the ideas transfer with some adjustments to other algebras).

It could also use some polish. It's awkward to be starting a new "episode" and find that it's two pages of off-topic discussion (presenting the case for the blog, which would serve better in an introduction than in the middle of the material).

</comment></comment><comment><USER4> Where is the text? Or is this an advertisement for a book?

Since this might get the right eyeballs here:

1\. Does anyone have a good intuitive explanation for the meaning of the transpose operation? It seems to tie into a central symmetry between columns and rows (or equations and variables) that I'm having trouble articulating for myself

2\. Why does every linear algebra book have a chapter on norms? It's always so incredibly boring and esoteric and I still haven't hit a situation where it's strictly necessary. The 2-norm seem adequate for most situations and comes out naturally from the least squares problem

PS: Strang is great. Meyer's "Matrix analysis and applied linear algebra" is even better (but more advanced)

<comment> man-and-laptop Two interpretations of transpose:

\- Let <-,-> denote an inner product. Then <Au, v> = <u, A^T v> is a definition of the transpose operation. Proof: (Au)^T v = u^T A^T v = <u, A^T v>

\- The transpose maps a vector v to a linear functional (a kind of function) v^T, such that v^T (u) = <v, u>. Conversely, a linear functional of a vector can be transposes to a vector. In fact, it's the latter (linear functionals to vectors) that's more interesting. This fact generalises to Hilbert spaces as the Riesz representation theorem, where the consequences can be pretty amazing.

\- An arbitrary linear operator L: H -> K tranposes to a mapping between their dual spaces L^* = K^* -> H^* by L*(f) = f o L.

\- The outer product produces rank-one matrices, and all rank-one matrices can be expressed as outer products.

<comment><USER4> Oh yikes. So the rabbit holes goes quite deep

So the transpose is really ties to the whole idea of inner product operators/function? (I'm not sure what the exact terminology is there)

So thinking out loud a bit about the first interpretation... The inner to me represents an operator that maps vectors to a scalar that denotes the degree of "sameness" between two vectors. And it's a whole family of operators that all share certain properties. It just so happens that to write out this operator in matrix notation (for the standard inner product) we need to transpose/rotate the first vector which is yucky and why we prefer the bracket notation

It's a cool insight but it just makes it seem like a mechanical operator that flips a column into a row to make things work for one family of operators. I'm thinking more like in the case of an orthonormal matrix/basis. We know the transpose is it's inverse. It stems from the standard inner products of the columns being equal to one which is I find kinda interesting b/c the inner products suddenly become part of linear systems and not just a separate measurement of a degree of sameness.. but the headache for me is that I can picture an orthonormal basis, but I can't picture it's inverse! :)

PS: The orthonormal basis case and the transpose by extension further makes me feel that only the standard inner product seems to really map to something directly applicable in linear systems

PPS: The 3rd bullet is a bit beyond me. And the 4th is also very interesting but I'm not sure how to expand on that to build an intuition haha. I'll need to digest it further

</comment></comment></comment><comment><USER5> Hadrien's book is so engaging I couldn't stop reading.

It's superbly illustrated. It steadily and seamlessly progresses through each topic that you don't realize you're actually learning 'deep learning'.

I'm sure this book will get lots of praise pretty soon.

Thanks for sharing it ghosthamlet. Thanks for writing it Hadrien.

</comment><comment><USER6> Looks like some great information but you need to change the way you style the links to the different chapters. The links look like ordinary text and I had no idea that I could click them until I accidentally hovered over one.

<comment><USER7> Thanks! It was a style error. I just fixed it!

</comment></comment><comment><USER8> Thank you for doing this. I'm currently working with deep learning but have never had Linear Algebra in school. Resources like this one, and the 3Blue1Brown video series on YouTube are a really nice way to get started.

<comment><USER9> 3B1B is by far the best resource on LA anywhere in the Web. I might be chastice for saying it but i will go as far to say that 3B1B is better than MIT's LA.

<comment><USER10> 3B1B is definitely more useful for applied purposes, but the MIT LA introduces you to the topic formally, and helps you understand research papers.

</comment></comment></comment><comment><USER11> > _A tensor is a n-dimensional array with n >2_

This is just one example of why it is usually better to learn stuff from more authoritative sources. (On the other hand, I can't help but recommend this amazing video: [https://m.youtube.com/watch?v=CliW7kSxxWU.](https://m.youtube.com/watch?v=CliW7kSxxWU.))

</comment><comment><USER12> Read Introduction to Linear Algebra by Gilbert Strang; should be all you need. There are the MIT OCW lectures that you can use too.

<comment><USER13> Obligatory remark that "reading" a math textbook, and even moreso a basic one, is an active task; you can get the intuitions from youtube videos of the 3Blue1Brown variety, but to really learn you need to follow the text closely, put question marks on passages you're not 120% comfortable with, do the proofs that are left to the reader and the recommended exercises. If you're super comfortable with the material, you should do the more challenging exercises, usually marked with asterisks.

Basically you need a pencil, a lot of scratch paper and a capable waste basket; or a whiteboard all to yourself (but I get tired from being on my feet for hours on end).

\----

E: My litmus test is the Gershgorin circle theorem. Every so often I check if I can still prove it, and if I do I try to review the surrounding matrix. I will literally vote against hiring anyone who can't at least handwave why that's true.

<comment><USER14> >My litmus test is the Gershgorin circle theorem. Every so often I check if I can still prove it, and if I do I try to review the surrounding matrix. I will literally vote against hiring anyone who can't at least handwave why that's true.

Interesting comment with no context—i.e. not hire someone for what? I don't know if I would ever not hire someone for not understanding a math problem (unless the job was heavily math related in the sphere of the problem). I would definitely not hire someone who communicates as ineffectively as you did in this comment.

<comment><USER15> Reminds me of: [http://philip.greenspun.com/humor/mcdonalds- joke](http://philip.greenspun.com/humor/mcdonalds-joke)</comment></comment></comment></comment>


Simply Secure - <AUTHOR> https://simplysecure.org/

<comment><USER2> Comments moved to [https://news.ycombinator.com/item?id=8335310](https://news.ycombinator.com/item?id=8335310).</comment>


Worth staying in Austin? - <AUTHOR>

I started Physics grad school this Fall, but I have recently considered dropping out in order to find a job in industry (I'd like to work at a startup). I know this could look really bad to employers, but I just have no motivation to continue my studies
Recently I've been working on a programming project on my own (a sort of video game), as a way to improve my programming skills, and I've been working on it with alot more motivation than studying for my Physics classes. I'm still fairly new to programming so I can't say I'm committed to programming over Physics yet
Anyways, the semester is almost over and I have to make a decision soon as to whether to move back home (Los Angeles) or stay in Austin to find a job. Ideally, I would like to work as a programmer for a computer software startup. That is because after reading Paul Graham's essays, I think I'm willing to take the risks involved in running my own business or joining someone else's startup.
But my programming skills aren't that great and my statistical analysis software skills aren't either (I've only used SPSS minimally). Also, I have no idea as to what kind of startup I'd like to work for. I'm not interested in Iphone apps, social networking, etc. But analytics seems pretty interesting.
Would I really be missing out on alot of opportunities if I moved back to LA instead of staying here in Austin? <comment><USER2> Nothing says you cannot continue your education back in LA. Also, nothing says you cannot dive deeper into the world of startups in Austin, either. If I were you, I'd put some more thought into what you actually want to do. You sound interested in programming and startups, but I don't think it sounds like you know enough to actually know what you'd be getting yourself into if you just moved back to LA immediately. With how much programming you describe yourself as knowing, it would probably be difficult to find a job at a startup, too.

I guess it all just depends on your scenario and stuff, but from what you've described, I'd say stick it out with at least another semester, but make it a goal of yours to really think about what you want to do during that semester.</comment>


Dr. Bunsen's coffee experiments - <AUTHOR> http://www.drbunsen.org/coffee-experiments/

<comment><USER2> This is a great rundown. Two things for consideration:

-Part of the benefit of a burr grinder is that you get consistent results. For espresso, where the grind affects how much time the water spends in contact with the grounds, it's essential. This might be why burr grinders are generally held in higher esteem. For coffee, this doesn't matter as much.

-Another benefit to a burr grinder is that you don't have to hold the darn thing down while you're grinding coffee, or turn it upside down and risk dumping grounds all over the place.</comment>


How an old hacking law hampers the fight against online discriminationĺ - <AUTHOR> http://www.newyorker.com/business/currency/how-an-old-hacking-law-hampers-the-fight-against-online-discrimination <comment><USER2> > stay away from: in sales for 8-10 years.

There are definitely startups that do the "stay away from: in development for 8-10 years", however it's worded as "must be enthusiastic code ninja."</comment>


Hurricane Harvey was not a catastrophe - <AUTHOR> http://www.houstonchronicle.com/opinion/outlook/article/Linbeck-Hurricane-Harvey-was-not-a-catastrophe-12174976.php <comment><USER2> This piece has value. This passage from it is a morass of cognitive dissonance and bad faith rhetoric:

"The claim that CO2 causes worse hurricanes is unproven and controversial, even to believers in climate change. Regardless, even if you believe that CO2 is causing climate change, you should be thanking the energy entrepreneurs in Houston for bringing cheap, clean natural gas to the nation. The increasing use of gas in power generation has led to a much-improved carbon dioxide picture in the U.S."

<comment><USER3> His comparison of wetland absorption and rainfall is comparing apples to oranges - if his numbers are accurate in the first place; which given the lack of citations and a piece that clearly is trying to prove a point, I think is an unreasonably optimistic assumption.

His scaling of the costs to a personal budget is also misleading (not terribly so, but still). Individuals have buffers that are proportionally much larger than those of large organisations; and if indeed you encounter a setback that's larger than you can absord you usually have a whole network of contacts to help you mitigate the effects. Conceptually: relying on your neighbors doesn't work so well when your neighbors were hit too. The comparison isn't crazy, but it's a little misleading nevertheless.

If the core premise of this piece really had value, then city of houston should be comfortably able to cover the bill without undue burden, and not need support from texas or the federal government. That does not appear to be the case.

Also: note that the estimates of damage almost certainly only include straightforward economic damage. That's of course an absurd proposition; much will have been damaged in houston that has value to various people but simply isn't trivially measurable. Losing family heirlooms, pictures... your house... does damage beyond the trivial value of the object.

Finally: even _if_ it turns out the damage is merely 10s of billions and not hundreds (as he's implying), then it's still reasonable to assume it's worthwhile to mitigate that damage. Just because you _can_ deal with the setback doesn't mean it's best to ignore the risk.

<comment><USER4> It's pretty wild, he seems to suggest that because wetlands wouldn't prevent the whole thing, they aren't worth having, or something like that.

<comment><USER3> And it's totally normal in dynamic systems for even tiny buffers to have huge impacts on how the whole system behaves. It's sort of like saying having a network stream buffer is pointless because the complete transmission doesn't fit into the buffer at once. Say what? That just doesn't follow. And again, I really wouldn't take this guy at his word as to the numbers anyhow.

</comment></comment></comment></comment><comment><USER5> Most important line in this article

Leo Linbeck III is executive chairman of Linbeck Group, a Houston-based institutional construction firm and vice chairman of the Center for Opportunity Urbanism.

<comment><USER6> I think you're suggesting that because Linbeck is associated with a construction firm, he views the property damage as an opportunity, and therefore less of a catastrophe than others would.

I think Linbeck has a good point - Houston did not suffer nearly the level of disaster that New Orleans did. I say this with utmost respect for the individual and cumulative loss in both events! But comparing the amount of the city flooded, the effect on the population, the number of deaths (especially relative to total population), and the ability of the cities to maintain order, services, and support, I think it's pretty clear that while Katrina was a "catastrophe", Harvey wasn't in the same class.

[http://www.npr.org/2017/08/31/547568681/harvey-feel-like- kat...](http://www.npr.org/2017/08/31/547568681/harvey-feel-like-katrina-d-j- vu-not-so-fast)

[https://www.nytimes.com/2017/08/28/us/hurricane-katrina- harv...](https://www.nytimes.com/2017/08/28/us/hurricane-katrina-harvey.html)

</comment></comment><comment><USER7> It's somewhat remarkable to me that nothing sort of a complete decimation of Houston would get people to recognize what a serious business it was.

What's more, it impacted a lot of neighborhoods that were populated by people without a lot of monetary resources, so these personal impact numbers are quite misleading.

And of course, at the end we have this "even if you do believe in climate change" the country should be "thanking Houston" for bringing "clean" natural gas to the nation? What? Who even raised this point for rebuttal? This is like walking into a coffee shop and the barista suddenly shouting, "NO THERE CERTAINLY ISN'T A DEAD BODY BEHIND THIS COUNTER!"

Why is this political/economic spin job on hacker news?

</comment><comment><USER8> Hey, less than 1% of global population died during the second world war, so I guess it wasn't a catastrophe either.

</comment><comment><USER9> > "This is like someone who makes a salary of $60,000 having suffering loss of > $6,000 to $12,000."

This line had the opposite of the intended effect, for me. Someone with $60k salary, a $12k loss could take years to recover from if they have expenses like college debt, rent/mortgage, and kids.

I dunno, some might say that's poor financial planning, but it's reality for a lot of people. And de-referencing the analogy: most US cities are not exactly financially rock solid either.

</comment><comment><USER10> "Tales from 'narrative spinners' are trying to change our city's formula for success"

No offense, but I don't necessarily trust a local paper to be a no-spin-zone about the disaster either.

</comment><comment><USER11> I agree that Harvey was not nearly as bad as it could have been. In fact several people that I spoke to (who themselves could document) would likely argue that the Army Core of Engineers caused more damage than Harvey did... that is, their home didn't flood until after the water releases from the dams.

That said, the amount of fellowship and effort being put together by the communities in Houston is a most definitely a picture of what it looks like to confront challenges head on. Seeing a flooded neighborhood filled with people working together to strip homes and start the repair process (even if they didn't have insurance) was downright amazing.

Kudos to Houston for sticking together and being good neighbors to each other.

<comment><USER12> The Corps released water presumably because they were afraid that the dam might fail if they didn't.

<comment> aaron-lebo During the height of the storm the spillways came in use (due to so much water). That happened at 108 feet and the top of the dam was 118. This happened in spite of the engineers releasing water for hours. Had they not done this those dams would have catastrophically failed.

[https://www.washingtonpost.com/news/post- nation/wp/2017/08/2...](https://www.washingtonpost.com/news/post- nation/wp/2017/08/28/houston-releases-water-from-two-dams-in-attempt-to- prevent-uncontrolled-overflow/?utm_term=.9fb755c1e1aa)

The person you are replying to should make fewer assumptions about the work of engineers outside of their domain.

<comment><USER13> I still don't understand how water can raise an extra 10 feet over the spillway. Isn't a bathtub only as high as its lowest side?

<comment><USER14> It can happen if water is entering the lake faster than it can exit.

That's why a river can crest much higher than the water lower than it - it's a dynamic level, not a static one.

</comment></comment></comment></comment></comment><comment><USER15> I find it ironic that he lauds the Houston sprawl for keeping housing prices low. He makes some very excellent points about how the rest of the nation has perceived or had the storm presented to them. But his "efficient use of land" argument for paving over huge tracts of wetlands is absurd.

"As a result, it's easier to develop real estate than most cities, which keeps real estate prices - especially housing prices - low relative to the rest of the country."

Easier development != intelligent, sustainable or ecologically friendly.

<comment><USER13> The most egregious example of sprawl and lack of zoning that I learned from Harvey was that there are residential neighborhoods built _inside the reservoirs_. There were homes being flooded well before the reservoirs reached even the spillway points as it was assumed they just wouldn't fill up that high.

<comment><USER16> Its TX, zoning laws don't cover things like building apartments next to fertilizer (explosives) plants or anything else that infringes on peoples right to make a buck.

I live near a TX lake, and full is defined at some level less than the spillway height. So, there are houses that are built above the full line, but below the spillway. Every dozen or so years those houses get flooded when the dam authority prioritizes flooding those houses over flooding the downstream communities.

</comment></comment></comment><comment><USER17> Meanwhile Trump has signed a $15B disaster aid package for Hurricane Harvey. And while most Americans, myself included, don't mind the financial aid to those in need it _is_ money that could have been spent on other things rather than the replacement of existing capital. This spend represents a lost investment, a lost opportunity. As such, this article makes light of a serious matter and really isn't helping in driving the policy discussion forward.

<comment><USER18> I argue that the 15b isnt just replacing lost capital but is an investment. I think you underestimate how much houston contributes to our economy.

<comment><USER17> Let me put it this way: would Houston's mayor prefer to receive a check for $15B to invest where needed for the future and growth of Houston or to replace stuff damaged by a storm? That's what I mean by this spend being a lost investment, a lost opportunity.

Maybe you're trying to point out it's not totally lost: the spend will make Houston incrementally better at withstanding storms of this magnitude in the future. If so, there's still a huge portion of that spend that's simply replacing lost capital.

</comment></comment></comment><comment><USER12> With so many cars destroyed, maybe Houstonians will try taking the bus.

<comment><USER4> It certainly seems like an opportunity of some kind. I was thinking about this the other day. It's not often you have such high changeover of vehicles on the road. Could you incentivize everyone to go electric together? Start up some kind of city-wide transit co-op with auto insurance payouts as seed capital?

</comment></comment><comment><USER19> This is simple, then. If it's not a disaster, it doesn't need federal relief funds. Let Texas pay for this damage through their own taxes.

</comment><comment><USER20> "Ok Exxon we published your article, please make the check payable to...."</comment>


Elon Musk shares footage of Boring's first working car elevator - <AUTHOR> https://techcrunch.com/2017/07/26/elon-musk-shares-footage-of-the-boring-companys-first-working-car-elevator/ <comment><USER2> This is in response to Mark Zuckerberg blasts Musk warnings against artificial intelligence as 'pretty irresponsible'

[https://www.bizjournals.com/sanjose/news/2017/07/24/elon- mus...](https://www.bizjournals.com/sanjose/news/2017/07/24/elon-musk- artificial-intelligence-risk-zuckerberg.amp.html)

<comment><USER2> Oops ignore the above comment, it was meant for other post.</comment></comment>


Is The Left Hand of God the next big fantasy novel? - <AUTHOR> http://www.keepingthedoor.com/2009/08/20/is-the-left-hand-of-god-the-next-big-fantasy-debut/

<comment><USER2> I don't know, but while gathering material for a mildly snarky reply I was surprised to learn that romance novels (often thinly-disguised porn) are probably the biggest-selling e-book category, followed by SF and fantasy. Readers like escapism during a recession, and e-books are cheap enough to be a guilt-free discretionary purchase.

[http://www.teleread.org/2009/04/08/romance-novels-are-big- in...](http://www.teleread.org/2009/04/08/romance-novels-are-big-in-the-e- book-world-says-new-york-times/)</comment>


Gemnasium command line 1.0.0 is out - <AUTHOR> http://blog.tech-angels.com/post/44630988143/gemnasium-gem-1-0-is-out-because-security-matters

<comment><USER2> Finally a way to send our dependencies without giving full access to our private repos. Thanks guys !</comment>


Better Place to file for bankruptcy - <AUTHOR> http://finance.fortune.cnn.com/2013/05/24/exclusive-better-place-to-file-for-bankruptcy/?iid=HP_River

<comment><USER2> My initial reaction is that this is a turning point in electric car technology. If there was one company suited to take the role in battery swapping like Tesla did for electric cars in general, it was Better Place. With them gone, and battery technology rapidly improving, battery swapping for consumer cars may never take off.

</comment><comment><USER3> Just finished reading [Wide Lens][1] about innovation of ecosystems, why things can fail even if you do everything right if you ignore the ecosystems. One of their main example for the complete system, for a company which did thing right, was Better Place. I was just thinking to compare the Tesla model with Better Place. Well, I still think that the book is very insightful, just there's more to the story than it was written at that time...

[1]: [http://www.amazon.com/The-Wide-Lens-Strategy- Innovation/dp/1...](http://www.amazon.com/The-Wide-Lens-Strategy- Innovation/dp/1591844606) "Wide Lens on Amazon"

<comment><USER4> I think the main reason better place failed wasn't due to ecosystem risk. The product was just too expensive hence with little value to price and came with a pretty high risk.

All those were caused by limits of current technology, and by the need to sell in small countries(limited high end market) where charging networks could be built.

</comment></comment><comment><USER5> I wasn't familiar with Better Place, but the headline reads as though it would be an article outlining WHERE one should file for bankruptcy for strategic reasons.

</comment><comment><USER6> It's somewhat sad. I really hope Better Place's demise happens because battery-swapping lost to just-keep-the-battery-in-the-car-and-charge-it strategy; not because oil-is-still-more-economical. :-/

But seriously, how will we ever be able to drive truly long distances with EVs? Super-charger stations that recharge batteries in a very short time?

<comment><USER7> I'm pretty sure that heavily parallel charging of batteries made up of smaller battery cells in special supercharging stations will be the solution, combined with charging at home when you can afford to wait eight hours for charging the battery slowly.

At the moment this is just a question of existing battery technology improving enough. Right now we are in the region where this is just borderline feasible, but in five years I'm pretty sure it will seem like a no-brainer. Tesla Motors is currently building supercharging stations all over the US, and it remains to be seen whether their approach will work. Note that they are a private company with no current government involvement, and we are now a few years into the future from when Better Place started rolling out their technology. Timing is everything in this game - the obvious strategy will seem like a bad idea until suddenly it isn't.

<comment><USER6> Hmm, according to <http://www.teslamotors.com/supercharger> Tesla now promises to charge 150 miles of range worth of battery in 30 minutes. This isn't bad, though of course far from perfect. But yes, parallel charging of sub-batteries sounds like a good idea, one I was also thinking about at some point. It definitely sounds like (and I hope it's no more than) an engineering problem at this point.

</comment></comment></comment><comment><USER8> Better Place always seemed to me like a marketing stunt. I am really not that surprised this happened. The idea, although, is still interesting. I guess another lesson of the big difference there is between a good idea and a successful implementation.

<comment><USER9> it was. the ceo stole the idea from a small-time silicon valley inventor, while said inventor was soliciting him for money. thus it was never in the US or EU where patents applied.

<comment><USER4> Interesting, got any links?

</comment></comment></comment><comment><USER10> Aside from the huge money lost the investors have, my heart goes to the ~1000 car owners that are now stuck. I hope that there will be some money left to compensate them for being true early adopters and believers.

<comment><USER11> I am not sad for these particular investors, because they could've become very rich if it had taken off. With great chance for cash comes great risk of losing it and they knew it. I do feel for the early adopters, though; I hope Better Place finds some money to compensate them.

For future investors, Better Place will be a reminder not to invest in ideas that are too disruptive, even if the founder and the team seems right for the job. The companies that might never be due to this precedent is the real loss, I think.

</comment></comment><comment><USER12> Battery-swapping as a thing for the general public's use of electric vehicles always struck me as just stupid. It works against an important advantage of EVs (no more detours to gas stations), requires standardization of a nascent product space (does that _ever_ work?), adds costs (at the very least, that machinery must be maintained), and confers no advantage at all for the vast majority of car use cases.

The general public simply does not take long road trips frequently enough for a full network of battery-swap stations to be viable.

<comment><USER13> I guess standardization worked pretty good for automobiles, trains, planes, telephone, electric power, radio, heck even the internet.

For instance an industry charging standard could take off easily. I think Better Place just guessed wrong.

<comment><USER12> I think you fundamentally misunderstood my comment. Either that, or you fundamentally misunderstand every single product space you mention. Standardization of _nascent_ product spaces doesn't work at all. Most of the products you mention _still_ aren't really standardized decades or even centuries after their invention, and/or have competing standards.</comment></comment></comment>