skysight-inc/HackerNews huggingface dataset:
I'll try to give some short pointers.

1. Matrices represent linear functions between finite-dimensional vector spaces. That is, if you have a function f from V to W that satisfies f(ax + by) = af(x) + bf(y), then there is a matrix A such that f(x) = Ax, and vice versa.

Once you understand that, try to figure out what happens to those matrices when you compose functions. In other words, when you define h(x) = g(f(x)) (assuming that f and g are linear maps that can be composed in this way), then given the matrices for g and f, what will the matrix for h look like? You will end up with exactly the rules for matrix multiplication.

The reason that you call this result "multiplication" is simply that it behaves very much like the multiplication that you are used to from the reals. In particular, you get a ring on square matrices, with (matrix) addition and multiplication that satisfy a distributive law.

2. I personally think that those angles are a bit of a red herring. In particular, the cross product generalizes in a somewhat more complicated way to higher dimensions, and then you have to talk about determinants instead of angles. That would take too much time and space to explain properly here.

3. Set and the "element-of" relation are not defined in the usual sense. They are indeed simply assumed, and you just postulate the properties that they need to satisfy, a.k.a. the axioms of set theory. It's a way of thinking that takes some getting used to, but as an analogy, try to work through Euclid. He doesn't define points or lines, either, but only postulates properties that they need to satisfy.

4. Because 0.9999... is usually interpreted as a real number, and not as an infinite sequence of characters. As a real number, 0.9999... has no meaning except as a limit, and hence they must be equal. As infinite sequences of characters, 0.9999... and 1 are of course different, but that's not how we usually interpret them.

If you think that this is in your way when understanding Cantor's infinities, perhaps you should try to use the diagonalisation argument on infinite bit strings instead of on real numbers. That way, those kinds of subtleties simply do not arise.
Tent v0.1
I've read this piece before, but it's dated Sept 21st, 2012. What's up with that?
Tent.io Releases v0.1 Documentation and reference server: tentd
Awesome - glad to see a Google Maps alternative given some serious support like this. The headline is a bit sensationalist though, as $575k is not a large investment; It's basically angel money.
3. Control bad PR. Warrantless threats of litigation are attributed to the shell not the troll. As far as the press can see the troll is not involved.
Considering that we very likely sabotaged their nuclear program, I can't really blame them for attacking our banks.
Querying PostgreSQL datatypes in ActiveRecord with postgres_ext
Ok, thx. I think I understand now.
I'm getting -

An error has occurred: {"code":"ENOTFOUND","errno":"ENOTFOUND","syscall":"getaddrinfo"}
Im going to let someone give a better response for some of these, but i will touch on a few.

2) The dot product can be thought of the projection of one vector onto another, or: If i shine a light directly at one vector with the 2nd vector in between, how long will the shadow of the 2nd vector in the system be? Do an image search for dot product to see this, and it will become clear (if you know basic trig) why the equation is ABcos(theta).

The cross product is defined as having a magnitude equal to the area of the parallelogram that the vectors create. So have both vectors start at the same point, and then mirror them to make a parallelogram (see wiki on parallelogram).

4) How are the different? If you take 1-0.9999.... = x, what is x exactly? You can't tell me the difference. This is essentially how limits work.
Depends on your POV. Personally, I like it. Anecdotally my cousin, independently of me I might add, has just bought an 13" MBA and he seems to think it's like a breath of fresh air. Horses for courses. But, yes, whatever you are using is the best.
This actually supports my point.

I've read in several places that the public perceived it as a broken promise and it's a major reason why he lost to Bill Clinton.

The message Republican politicians took away is: The public doesn't interpret anti-tax promises narrowly; if you make one, you'd better stay the heck away from anything that looks remotely like raising taxes.
Whilst I agree with the basic thesis of "charge more and compete by providing value".
The difficult part for me seems to be finding people who have money they can part with in the first place, you can't really sell somebody on the benefits of something they can't afford.

I've recently been trying to pick up some part time freelance work to supplement my income and pick up a wider range of experience.

So first stop was elance.com/Guru.com and similar sites. Looking at the jobs it seems like around 90% of the bids were from individuals in India or the far east happy to work for $7 per hour. So I figured I could "compete on quality" , however a lot of the individuals I would be competing against had CS or design degrees (often from western universities) , 5+ years experience and portfolios full of slick looking corporate websites.
Besides, at the rates on offer I figured I'd have to complete at least one fairly large project a week to match my current salary and I'm not confident about producing quality on those kind of deadlines.

Most of the project descriptions were also either extremely vague (I want a website), impossible (I want a website, must be #1 on google for <competitive search term>) or possibly illegal (I want a keylogger, must not show up on AVG).

It also seemed like a lot of the bids came from various outsourcing companies who had a bunch of different skills in house and providing 24 hour coverage which would kill my timezone advantage (besides a lot of buyers were in the US when I'm in the UK or were in India/Far East themselves).

Looking at the profiles of freelancers from the US/UK etc , most of them appeared to have never won a project despite being on the site for over a year often.

So I gave up on that and figured, "It's all about networking right?" so I attended a local business networking event for "entrepreneurs". First bad sign was after sitting down and introducing myself to the lady next to me, "what do you do?" , "I build websites , computer software and mobile apps" , "wow, you TOO".

Everyone there who wasn't a freelancer of some description desperate for business was either a recent university grad full of enthusiasm, bright ideas but no funds at all or some small mom and pop operation who were stressed out about meeting their mortgage payments that month and absolutely not looking to drop a chunk of change on any kind of bespoke software.

Now I'm sure there are people out there with money to spend, but they are probably hiding behind an army of secretaries etc. Besides even people with money are looking to save it, and there are plenty of monied businesses like investment banks etc who are still offshoring all of their dev work.

Any bright ideas on how to break through this firewall?
Email is for work, as Facebook is for personal
today I figured out that I use email completely for work.. all my personal life messages are now been handled in facebook, twitter and whatsap. This is an interesting trend.
Name and shame, so we can flag their posts.
Has anyone here read Ramit Sethi's book? Thoughts? I'm thinking about picking up the Audible version.

By the way, thanks for this podcast, Patrick, I'm about to listen to both parts.
For #2 and to some extent #1, see the earlier link I posted about Geometric Algebra. For #1, you want to find a good linear algebra book or resource. I never watched them, but I’ve heard that Gil Strang’s MIT 18.06 lectures are good. http://www.youtube.com/course?list=ECE7DDD91010BC51F8

For #3, try to find Halmos’s book Naive Set Theory. It has a very nice and accessible explanations.
> Contrary to what the article states, computers that compete against each other will tend to eliminate all short term unjustified price swings and leave only accessible prices based on real company fundamentals.

This is assuming that computers only try to extract money by going long on every stock they purchase, an incredibly ignorant view of finance.
Good for a company if they don't need to spend in advertising. For me, in an ideal world word of mouth if the product is good should be enough.

Apple master the process of creating expectations and surprising people, in their staged announcements, good for them.

Why the hate? envy?
If there was one Android phone released every year, it would get at least as much coverage as the release of the iPhone.
Tent.io v0.1 Documentation
I made an uneducated guess for why sgdesign disliked golang.org’s web design. I think an unearthly visual design is more appropriate for adventure games, less so for software tools. That does not mean that only “mysterious” visual design is good visual design.
some context: this was written by a guy who moved from california to washington state -- a state with no personal income tax -- just before his company was acquired for tens of millions of dollars. i'm not implying anything, just giving some context.
I would argue something is better than nothing. And if this gets people to start using the tool then maybe they will start to hit the cases where the loss of utility matters, and then this can be the source of inspiration to actually tough out the technical inspiration. Probably a long shot in general but it worked that way for me.
Newfound Planet a Top Contender to Host Life
> but the classic case for patents is in things like pharmaceuticals

That is also the classic case for patent abuse. Take a drug that works, tack on some non-active atoms somewhere, change the name, patent it, jack up the prices on the old drug when the patent is about to expire to push buyers to your new monopoly.
Microsoft Patches IE Zero Day And Fixes Four Other Flaws
The Heartbeat Philosophy
I was actually a PM before I became a developer. Do you think there is anything missing?
That is called "radical honesty" (http://www.esquire.com/print-this/honesty0707?page=all)
I completely agree, obviously there are many complications and other concerns that could make it a much more difficult task.

I envision most of the difficulty that exceptional.io has encountered has been related to scalability. If I wanted a small, simple, self-hosted application with this functionality, it will probably be simpler. I'm not guaranteeing this, but I'm making a good estimate based on my experience creating similar web apps and utilities throughout my career—this ain't no blind shot in the dark guess.

You're right, being programmers does not make us magically able to understand details of software. But being good software engineers does involve a lot of exactly that skill. They are separate and distinct skills, but most great programmers I know are also great software engineers, and also great estimaters of project complexity. In my experience, I am as well (in fact I am generally better at estimating project architecture, complexity and time than I am at programming itself). This is where my response comes from—not simply being a programmer. Apologies for the confusion.
There have been many attempts to solve the approachability problem by creating alternate syntaxes. Vaughan Pratt's CGOL, written almost 40 years ago, was perhaps one of the best.

Although these alternate syntaxes may be helpful to newcomers, they have never caught on. Expert users actually prefer the parenthesized form; so anyone working in Lisp for very long has to learn to deal with it -- and usually, once they do, they find it preferable.

You said it yourself: programmers preferred S-expressions, so they became the default.

The other important point here is that the non-Lispers are right, in a sense: editing Lisp without a paren-counting editor is just as tedious as one would expect. But with a paren-counting editor -- and even better, with something like Paredit that keeps the parens balanced at all times -- editing actually becomes easier, more fluid, and more pleasant than in other languages.

That is why expert Lisp users prefer the parens.
Startups kick asana with nerd yoga
Writing Conferences Fall 2012
Authentication chips discovered in teardown of Apple's new Lightning connector
Hiring is a numbers game
Apply for enough positions that you
Forget to Followup!
Got it right out of college -- it was great for giving me a kick in the ass to get my finances in order. Highly recommended.
Setback for Apple in German patent case
And I don't. Well OK, maybe once in a while, but I got off the TC train 'round about the "Arrington (supposedly) got spit on!" era.
What is this a parody of?
Good question. A lot of it really depends on the nature of the product. Is it purely mechanical or does it have electronics? Plastics? Metal? Any optics?

The set of disciplines to be mastered could be daunting. In such cases it is probably best to hire a product designer to help you get from a garage prototype to a manufacturable product or an interim product that is manufactured using an approach that is closest to production.

If you could provide a little more info as to the nature of the product I can certainly take the time to give you some pointers. I don't need to know what it is. What I need is an understanding of the technologies that you might require and if there's anything really critical in the design. For example, if it has lenses it might be critical to have them precisely aligned. Does it produce a lot of heat? What kind of power will it require? Batteries or powered off the wall?

The other important bit of data would be your current skill set (you and your friend).

Tools: For nearly all electro-mechanical products you will need specific industry-standard tools in order to be able to communicate with manufacturers and job shops. For example, I use Solidworks for mechanical design as well as thermal and flow simulation and Altium Designer for schematic and circuit board design. If the design involves programmable electronics you might be into tools such as Xilinx or Altera for FPGA's and Keil or other compilers for embedded stuff.

Lastly. Where are you? The approach might change a bit based on your geographic location and the locally available resources. You might, for example, be able to ping your local university for help.
2nd Annual SaaS Metrics Survey Results
And what is wrong with that? Seriously. Who is to say that one business model is better than another? Jaguar to Tiger was a big leap, as was Panther to Leopard; certainly as big a leap as XP to Vista.
While not in consulting, I have actually found the same to be true in selling advertisements on my website.

My original plan was to sell ads at rock bottom prices - thinking that because they were inexpensive, they would sell out quickly. What I found was that the advertisements didn't sell out, and I was making rock bottom wages. I recently upped the price by 10x and have already sold an advertisement at the price, effectively making in 1 sale what would have previously taken 10 sales.

I have also thought that advertisements at such low prices signaled low quality to potential advertisers, making them less inclined to purchase from me.
I'm doing pretty okay with Safari 4.1 on my PowerBook running 10.4. What exactly is "bit rot", are the magnetic particles on my disk going to grow mold?
Nifty Search Tricks To Significantly Enhance Google Results
Cirque du Soleil + Google = Innovation
> The only downside to spaced repetition is that most software implementations of it require daily review and don't work optimally if you miss a day

I don't think the efficiency penalty is that bad if you do it, say, every other day - I doubt the algorithms are precise down to the day.
An in-depth review of the Hotfix WordPress Plugin
Seems like they could get 100% of the ambiguity reduction they are probably going for with the "no renderings" rule by requiring that any renderings have a standard label. Some very noticeable and tasteful diagonal bar saying "Rendering" across the corner of the image would do nicely. Perhaps you could/should propose that to them as a sensible middle-ground position.

I really like the "you have to show what you have now" part of the requirement, but getting a look at where the creator wants to get to as a goal is also very useful for choosing projects. And your cutaway animation also sounds like a knock-down case for why renderings are needed sometimes.
If they waited for every customer to enjoy the unboxing experience then the line would have barely moved as everyone would be joygasming.

On the real.

The employees are trying to rush through the mass. They have the setup the phone, activate and etc for the account that they don't have the luxury of time for you to enjoy the unboxing experience. It is unfortunate for those who enjoy it - sure. But it is what it is and business is business. There are a hundreds of customers waiting and want to play with their phone and so they have to blitz through to fulfill every customer.
The Tour de France analogy is priceless. I wished the final conclusion were true "As always, for long term sucess the most important factor is working hard to create a good product.". It all starts with marketing unfortunately.
Show HN: Test Jade and EJS templates easily in the browser with view-test
A main one for me is that 'Shortcuts don't pay off in the end'. It hurts when you, as a developer, pour your sole into your app only to have your partners take shortcuts and purchase 'likes', or otherwise 'stuff the ballot-box'. Take the time to help develop sincere social and ad strategies for your app, and your potential for a higher-quality yield increases.
> When you make something useful for a market large enough to make a successful business out of, there is no mystery.

This statement is where a trope, meme, and axiom collide in a nuclear reaction. Sure there's no mystery, but you're describing the end state after you've already done all the analysis. Although you're also missing the 'profitability' metric, which is important.

make something useful for a market: How do you know what's useful? You've used the "saves time" metric a couple times here, but that isn't always enough. Bikes save time over walking, but people still walk. Cars save time over bikes, but people still bike. Ditch-digging machines are orders of magnitude faster than human ditch diggers, but people still dig ditches. Buying fast food saves time over cooking, but people still cook. Netflix is more efficient than cable and Redbox, but people still buy cable and rent from Redbox. Quickbooks is more efficient than paper bookkeeping, but legions of small businesses still use paper. The examples go on forever. You can't know if your product is useful unless it's fundamentally obvious (lightbulbs, toaster, eyeglasses, cups, dog food) and most products aren't this way. Most are incremental improvements on stuff we've owned or done forever. Is your product a significant enough increment? That's where validation comes in...

for a market large enough: The perpetual question. Total addressable market is not a simple thing to figure out. Surely you're familiar with the traditional startup pitch: If we could get just 1% of this billion-dollar market... It's a dream-killer, that one. And it's really only useful in context -- consider a theoretically perfect product like, say... perfect socks. They magically match whatever clothes/shoes you're wearing, automatically adjust thickness depending on your feet and shoes, wick moisture better than anything else, and never wear out. Addressable market: everyone who wears socks. Home run. But now say they cost $10,000/pair to manufacture. Total addressable market: like 500 people. From a home run to hit-by-pitch just like that. My point: TAM is important, and non-trivial to calculate for all but the simplest idea. Talking to customers helps figure out what segment of the market 1) wants your product and 2) will/can pay for your product.

to make a successful business out of: That means margin and profit. If your theoretical $300 sedan above cost $350 to manufacture, it doesn't matter how revolutionary your idea was. The LIFX bulb is a possible example of this. Can LIFX deliver on their product for $70/each? A lot of people are saying it's impossible. If it ends up costing them $100/bulb to make it exactly like their Kickstarter campaign says it will be, that business is not going to be a successful one. There are armadas of good products & services that went belly up because they cost too much to make compared to what people would pay.
I agree. There's no reason why this should continue once it's been outed like this.
Actually you can be 100% correct and 100% complete in mathematics. That's why I specifically said "outside of narrow formalisms".
> We, of course, have no reason to assume you have a private definition of lying that classifies statements we would consider true (or half-truth at most) a lie.

I am aware that it's my personal definition, but I thought I gave it right away:

> We all lie, everytime we open our mouths to say something. Whatever we say it's always biased, subjective, emotional (to varying degrees, ofc)

Sorry if that was not clear. Also, I think I have to admit the obvious: "Lying is good" was of course meant to be something akin to "linkbait", something which can kickstart discussion. Which it did, so I'm happy it worked.

(Before proceeding, please note that English is not my first language! It's hard to discuss these concepts even in my native language.)

Your "morality example" is almost exactly what I wrote a couple years ago in some essay :) But it's not really the same argument, the problem is that the "good" and the "bad" are indeed fuzzy, they mix, they're on the continuum, it makes perfect sense to say that something was more than 50% good and therefore it was good overall. This is not the case when talking about truth. If a sentence is half-and-then-some true and half untrue (@davidhollander, I'll try to avoid the term 'lie' outside of it's original meaning:)) we cannot say that the sentence as a whole is true. It is not 100% untrue, but it cannot be said to be the truth just because of that. At least I think so, am I wrong on this?

If I'm right, then "telling the truth, only the truth and nothing but the truth" is impossible, which some of the commenters seem to agree with. And this is where it gets interesting, because I want to tell the truth! Or at least I'd like to transfer the truth I think I know to someone else's head, which is even more of an impossibility. I have basically two choices here: either struggle to maximize the amount of true (like in 100% true) statements in what I say, but this a) still won't make what I'm saying the truth, b) could be counterproductive, because while struggling to tell the truth I'll fail to actually communicate.

The second option I see is to lie. Given some knowledge about a person I'm trying to communicate with and some imagination I can craft a lie, that will communicate the truth I know to this person to the greater extent, than the previous option would. Moreover, I think that both options are really similar, in that they are not truth anyway and there is the same intent behind them.

So, when I say "lying is good" I mean that often a lie, deliberate untruth, comes closer to the truth than something you struggle to make as true as you can.

And this is a response I wanted to give to the person who "doesn't understand lying". In the face of inability to express truth directly lying can be the most effective way of communicating as much truth as possible.

I hope that this time I expressed myself clearly, at least as much as possible :)
Instagram Cofounder Says Simple Apps Are Best
You're going to run into this on any social news site. Don't act surprised - it's the nature of the beast.