tripa

The book has two parts, both of which can reasonably contain a chapter of that name.

(speedcuber here too)

Two random squares being swapped isn't really something that happens in real life. But abstracting that, you'd notice as soon as you've placed the piece one of them is on, which is kind of hard to predict in general, it'll really depend on where it is wrt which side you started from.

What does happen in real life is two pieces ("cubies") getting swapped, say after assembling back up a popped cube. Using CFOP, you'd notice the inversion itself one sequence before the end, though you might notice the fact they're not oriented properly one sequence before that.

For more swapped pieces, (theory ahoy) there's two cases. Odd number of swaps: they're all equivalent to the case above. Even number of swaps: equivalent to no swap at all. Interestingly, you can cancel out an edge piece swap with a corner piece swap.

I hinted at it above, and it's related: no need for swaps, you can make the cube unsolvable by flipping an edge or rotating a corner in place. A CFOP solver would notice two sequences before the end. Edge flips cancel each other out by pairs; corner twists cancel each out by triplets of the same orientation. Contrary to swaps, there's no catching up a flip with a twist.

In all cases, almost-solving them is just a gasp of surprise away from solving an untainted one.

It is, but Lisp did have it first, even if not through Racket.

/dev/null behaves like an empty file, which is (or used to be?) a valid executable.

Cf http://trillian.mit.edu/~jc/humor/ATT_Copyright_true.html or https://twitter.com/rob_pike/status/966896123548872705

Here's a more neutral classic:

What is the difference between USA and USB? One connects to all of your devices and accesses the data, the other is a hardware standard.

TBC: Neptune was predicted from observed perturbations in the orbit of *Uranus.

Do you have stats at hand about people who whine software isn't available for their platform?

There's a “Contributing” link at the bottom of the page.

Many years ago, I've had a project manager reluctant to have us commit to the Hadoop ecosystem because, come on, "Pig", "Zoo"[keeper]... this can't be serious!

Sometimes people are the problem. Of course they're just names and have no incidence whatsoever on the relevance of a project. Until they do. For terrible reasons.

I love how the favicon's still a gopher.

> That's pretty wishful (or perhaps naïve) thinking. A family member of mine literary hasn't spoken to me in over two decades because I told her I didn't believe in god when I was 12. She asked me out of nowhere, I said no, that was it, I was no longer to be in her life in any capacity. She also tries to meddle in my business telling other people I am not to be trusted because "you can only trust someone who fears god."

I'm afraid I'm tempted to dismiss this as anecdote. This is one personal experience. That seems quite personal. That seems far more family-related than church-related.

> Its been my experience that most people who are devout enough to go to church are exactly the "convert or leave" type. Church is a very tribal place.

Not around here. Feels weird to "defend" it, I can't even remember when I actually last attended a service.

> Not to mention that the type of people who want to spend their time doing church activities are people I find horrifically boring and have ZERO common ground with.

Can we agree on the fact this has nothing to do with the initial controversy that churches would be unwelcoming to atheists? This only describes atheists' (well, yours, but you seem to intend to represent a global viewpoint) likely aversion to churches.

> May be less so if you're male.

I wish we didn't live in a world where this came up so often, but ok, now I'm this deep in the debate I will bite: what's this got to do with anything? Personal/local trivia or something deeper?

I actually don't see why it shouldn't. As mentioned above, most churchgoers are nice people, and I can't conceive of anyone throwing the atheist out on grounds of “convert or leave”.

This is the weirdest rationalization of three-phase power I've ever read. By your reasoning and disregarding cos phi issues, monophase power is also constant-zero power, since it's two wires anyway and one is always the opposite of the other.

The best explanation of why three I was ever given hinged on "it's the number-of-phases argmin for the needed volume of wiring".

Reminds me of the US imposing FATCA on the entire world.

I read that as: it gives the impression it's been here forever, it's still being actively maintained, and will be for the foreseeable future. Benefiting from the “future” (sqlite4/perl6) at a slow but steady peace. So, really like Perl 5.

It's fair indeed. For now. What I'd like to know is how we can get the situation to evolve.

When do we stop tying religion to geography?

Apparently it made it to the FAQ.

I love the idea, but can't help wondering: did it actually convert into "sales"?

Existence of language schools doesn't prove existence of native speakers.

I don't think submodules were designed by Linus.

I like how the original was agnostic, yet you interpreted as perl5 :-)

Then again I've got Perl code I wrote in the 90s that still runs untouched on the latest Perl 5. Much more recent Python 2 code (of mine) still won't run untouched under Python 3.

So I might agree actually on the "bigger", but the "noticeability" does have a lot to do with the general feeling.

(to be clear, I agree with all of your comment)

I use make as a poor man's substitute for rsync (well, local rsync. Like cp -r), when I need to add some filtering in between.

As compared to "introvert"?

Even the solver part is impressive.

A BFS is a few seconds, but modeling a Rubik's cube properly in a way a daughter would understand is... harder.

What optimal methods are you referring to? The paper doesn't really define one, and real world cubers sure don't use any.

Assuming you mean real life cubes, the most common [1] method to solve anything bigger than 3×3×3 is to first reduce to 3×3×3, then solve as a normal 3×3×3 using outer slice turns. On even-sided cubes, that reduction process is sensitive to a number of so-called "reduction parities", meaning in a nutshell that you might be recreating edges [2] in a configuration that isn't possible/solvable on a 3×3×3. This can't happen with odd cubes, because the center piece on faces and edges disambiguates from the start.

So really, most of what you need to know about solving big cubes is there on a 4×4×4, and not on a 5×5×5. To make it fully pedantry-proof [3], you need to know standard methods for both 4×4×4 and 5×5×5, both of which already require solving a 3×3×3.

[1] There are alternate methods that are actually used for 4 or 5 and don't have the "parity weakness", but they don't scale well enough to anything bigger.

[2] Or, obviously, faces, but in real life reducing faces in a valid configuration is considered a prerequisite.

[3] It kind of depends on who you ask whether or not the reduction methods are "the same" moving from 4×4×4 to 5×5×5. They're a direct extension, but they do involve pieces with no counterpart.

I can understand that the etymology is disputed, but what does the modern French expression of agreement have to do with it?

For all I know, it's entirely possible a misunderstanding/reappropriation of a foreign phrase could be it.

I agree with your comment; but I do have to point out the comment you're replying to specifically conceives a political landscape with more than two parties, that can indeed be considered as zero sum as well, yet two major parties can feasibly agree on something at a net loss for others.

I like Perl a lot better than awk, buy I do agree with the general sentiment of using the language that makes for the clearest code for the task at hand, especially the smaller ones. Which makes me a frequent awk proponent.

So I'm surprised at the following part of your comment:

> There is no reason to use perl in situation when awk kicks its butt with clearer, shorter code free of distracting author and other line noise

In my experience, the shorter ask code tends to be the one with sigils.