Which emoji scissors close?

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Ah, scissors. They’re important enough that we have an emoji for them. On your device, it appears as ✂️. Unlike the real world tool it represents, the emoji’s job is to convey the idea, especially at small sizes. It doesn’t need to be able to swing or cut things. Nevertheless, let’s judge them on that irrelevant criterion.

I’ve watched from afar as the Internet collapsed in on itself during a debate about what a cheeseburger looks like and I’ve raged a little myself at the popular depiction of juggling, but this newly-identified emoji failure is a whole new thing. Sure, emoji are supposed to be representative, not realistic. But if they have to cover sufficient diversity to include gender-neutral representations (which they absolutely should, and should have done in an early instance, but at least we’re fixing some of the issues in hindsight, like Ido did) then perhaps they could also include sufficient attention to detail that the tools they depict would actually, y’know, work?

It’s 2020 and you’re in the future

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West Germany’s 1974 World Cup victory happened closer to the first World Cup in 1930 than to today.

The Wonder Years aired from 1988 and 1993 and depicted the years between 1968 and 1973. When I watched the show, it felt like it was set in a time long ago. If a new Wonder Years premiered today, it would cover the years between 2000 and 2005.

Also, remember when Jurassic Park, The Lion King, and Forrest Gump came out in theaters? Closer to the moon landing than today.

These things come around now and again, but I’m not sure of the universal validity of observing that a memorable event is now closer to another memorable event than it is to the present day. I don’t think that the relevance of events is as linear as that. Instead, perhaps, it looks something like this:

Graph showing that recent events matter a lot, but rapidly tail off for a while before levelling out again as they become long-ago events.
Recent events matter more than ancient events to the popular consciousness, all other things being equal, but relative to one another the ancient ones are less-relevant and there’s a steep drop-off somewhere between the two.

Where the drop-off in relevance occurs is hard to pinpoint and it probably varies a lot by the type of event that’s being remembered: nobody seems to care about what damn terrible thing Trump did last month or the month before when there’s some new terrible thing he did just this morning, for example (I haven’t looked at the news yet this morning, but honestly whenever you read this post he’ll probably have done something awful).

Nonetheless, this post on Wait But Why was a fun distraction, even if it’s been done before. Maybe the last time it happened was so long ago it’s irrelevant now?

XKCD 1393: Timeghost - 'Hello, Ghostbusters?' 'ooOOoooo people born years after that movie came out are having a second chiiiild right now ooOoooOoo'
Of course, there’s a relevant XKCD. And it was published closer to the theatrical releases of Cloudy with a Chance of Meatballs and Paranormal Activity than it was to today. OoooOOoooOOoh.

When you’re in the club and you’re hungry… (Misheard Lyrics… Round Two!)

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My mother has long argued that a large category of popular music, second only to those on the subjects of sex and drugs, are about food. This so-called corpus of food songs is, I’m pretty confident, mostly based on mishearing lyrics, but I think she’d have a friend in the fabulous Bec Hill who’s this month made a follow-up to her video When You Listen to the Radio When You’re Hungry. And it’s even better (and to my delight, paella still manages to make a cameo appearance).

Unfortunately Warner Music Group don’t seem to have a sense of humour and you might find that you can’t watch her new video on YouTube. But thankfully that’s not how the Internet works (somebody should tell them!) and if proxying isn’t the best solution for you then you can just watch her new video on the BBC’s Facebook page instead.

Howdymattic Outtakes

Yesterday, I shared with you the introduction video I made for my new employer. A few friends commented that it seemed very well-presented and complimented me on my presentation, so I thought I’d dispel the illusion by providing this: the “outtakes”. My process was to write a loose script and then perform it multiple times (while being sure to wear the same hoodie) over the course of several days as I walked or cycled around, and then take only the “good” content.

That I’m able to effortlessly make a longer video out of a selection of the outtakes should be evidence enough that I’m just as capable of mucking-up a simple task as anybody else, probably moreso.

You may observe in this video that I made a number of “Hey, I found a…” snippets; I wasn’t sure what would scan best (I eventually went with “Hey, I found a… nothing?”). Folks who’ve seen this video have already criticised my choice; apparently the cow I found was more photogenic than me.

Also available on: VideoPress, QTube, YouTube.

Time-Efficient Shuffling

Some years ago, a friend of mine told me about an interview they’d had for a junior programming position. Their interviewer was one of that particular breed who was attached to programming-test questions: if you’re in the field of computer science, you already know that these questions exist. In any case: my friend was asked to write pseudocode to shuffle a deck of cards: a classic programming problem that pretty much any first-year computer science undergraduate is likely to have considered, if not done.

Interview with paper visible.
Let’s play at writing software. Rather than a computer, we’ll use paper. But to make it sound techy, we’ll call it “pseudocode”.

There are lots of wrong ways to programmatically shuffle a deck of cards, such as the classic “swap the card in each position with the card in a randomly-selected position”, which results in biased results. In fact, the more that you think in terms of how humans shuffle cards, the less-likely you are to come up with a good answer!

Chart showing the probability bias for an incorrectly-implemented Fisher-Yates shuffle, for a 6-card deck.
If we shuffled a deck of six cards with this ‘broken’ algorithm, for example, we’d be more-likely to find the card that was originally in second place at the top of the deck than in any other position. This kind of thing REALLY matters if, for example, you’re running an online casino.

The simplest valid solution is to take a deck of cards and move each card, choosing each at random, into a fresh deck (you can do this as a human, if you like, but it takes a while)… and that’s exactly what my friend suggested.

The interviewer was ready for this answer, though, and asked my friend if they could think of a “more-efficient” way to do the shuffle. And this is where my friend had a brain fart and couldn’t think of one. That’s not a big problem in the real world: so long as you can conceive that there exists a more-efficient shuffle, know what to search for, and can comprehend the explanation you get, then you can still be a perfectly awesome programmer. Demanding that people already know the answer to problems in an interview setting doesn’t actually tell you anything about their qualities as a programmer, only how well they can memorise answers to stock interview questions (this interviewer should have stopped this line of inquiry one question sooner).

Riffle shuffling
Writing a program to shuffle a deck takes longer than just shuffling it, but that’s hardly the point, is it?

The interviewer was probably looking for an explanation of the modern form of the Fisher-Yates shuffle algorithm, which does the same thing as my friend suggested but without needing to start a “separate” deck: here’s a video demonstrating it. When they asked for greater efficiency, the interviewer was probably looking for a more memory-efficient solution. But that’s not what they said, and it’s certainly not the only way to measure efficiency.

When people ask ineffective interview questions, it annoys me a little. When people ask ineffective interview questions and phrase them ambiguously to boot, that’s just makes me want to contrive a deliberately-awkward answer.

So: another way to answer the shuffling efficiency question would be to optimise for time-efficiency. If, like my friend, you get a question about improving the efficiency of a shuffling algorithm and they don’t specify what kind of efficiency (and you’re feeling sarcastic), you’re likely to borrow either of the following algorithms. You won’t find them any computer science textbook!

Complexity/time-efficiency optimised shuffling

  1. Precompute and store an array of all 52! permutations of a deck of cards. I think you can store a permutation in no more than 226 bits, so I calculate that 2.3 quattuordecillion yottabytes would be plenty sufficient to store such an array. That’s about 25 sexdecillion times more data than is believed to exist on the Web, so you’re going to need to upgrade your hard drive.
  2. To shuffle a deck, simply select a random number x such that 0 <= x < 52! and retrieve the deck stored at that location.

This converts the O(n) problem that is Fisher-Yates to an O(1) problem, an entire complexity class of improvement. Sure, you need storage space valued at a few hundred orders of magnitude greater than the world GDP, but if you didn’t specify cost-efficiency, then that’s not what you get.

Stack of shuffled cards
If you’ve got a thousand galaxies worth of free space you can just fill them with actual decks of cards – one for each permutation – and physically pick one at random. That sounds convenient, right?

You’re also going to need a really, really good PRNG to ensure that the 226-bit binary number you generate has sufficient entropy. You could always use a real physical deck of cards to seed it, Solitaire/Pontifex-style, and go full meta, but I worry that doing so might cause this particular simulation of the Universe to implode, sooo… do it at your own risk?

Perhaps we can do one better, if we’re willing to be a little sillier…

(Everett interpretation) Quantum optimised shuffling

Quantum ungulations
If you live in a universe in which quantum optimised shuffling isn’t possible, the technique below can be adapted to create a universe in which it is.

Assuming the many-worlds interpretation of quantum mechanics is applicable to reality, there’s a yet-more-efficient way to shuffle a deck of cards, inspired by the excellent (and hilarious) quantum bogosort algorithm:

  1. Create a superposition of all possible states of a deck of cards. This divides the universe into 52! universes; however, the division has no cost, as it happens constantly anyway.
  2. Collapse the waveform by observing your shuffled deck of cards.

The unneeded universes can be destroyed or retained as you see fit.

Let me know if you manage to implement either of these.

So You Want To Start An Unpopular Blog

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Very occasionally I get asked how to start blogging by people who would like to create exciting and engaging articles that will build a following by delighting an audience hungry for more. Perhaps they envision spreading their views far across the face of the web.

To which I always reply, “Have you read my blog? I don’t know about any of those things!”

What I do have are 10 years of logs and some vague observations about beginning a blog.

As I’m sat here anyway, helping people get started on the Indieweb, here’s a great (tongue in cheek) look at how you can expect your new blog Indieweb presence to take off and become the Most Popular Thing Ever. Or rather, not.

But as I and others have said before, my blog is first and foremost for me. If you get something out of it too, that’s great, but that’s a secondary goal!

Caverna Do Dragão

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Dungeons & Dragons (80s TV show)Remember that 80s TV show Dungeons & Dragons?

It turns out that Renault’s target customer base in Brazil do, too. Presumably it was a way bigger deal over there than it was here, because this new car ad feels like it could genuinely be a trailer for a live-action reboot of the series. And now I want to watch it.

(I do have some questions, though. Like: Diana was only 14 years old when she and her friends were transported to the Realm of Dungeons and Dragons… so when did she learn to drive? Am I supposed to believe that she just rolled a natural 20 on that driving check? And where does Sheila go when she turns invisible so that Bobby doesn’t end up sitting on her transparent-lap? And how does the car’s navigation computer work: are we to believe that there’s a GNSS network in the skies above the Realm? The Internet must know!)

Danny Daycare

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“Have you had a good wee day out?”

This isn’t how I behave when I’m out cycling with one of our little ‘uns in tow. But sometimes, just sometimes, when I see a solid-looking jump… I wish it could be. Honestly: our eldest would be well up for this! (And would probably be quite disappointed to sit around until the end where they reveal that, obviously, they swapped the small child for a doll for many of the shots.)

Jon Snow oh oh EXTENDED REMIX oh oh oh oh oh oh oh oh oh oh oh oh oh

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This epic video (which contains spoilers for Game of Thrones through the third episode of season eight The Long Night). If you’re somehow not up-to-date, you can always watch the earlier iteration, which only contains spoilers through The Spoils of War, the fourth episode of the seventh series.

And now my bedsheets smell like Jon Snow.