Weekly Head Voices #99: No-lands.

This is without a doubt my favourite animated GIF of all time (go ahead, click on the play button!):

I am eternally grateful to Twitter user @ftrain for granting us this gift. In the process, I also learnt that:

  1. Twitter automatically transcodes animated GIFs to MP4s to save bandwidth, and for other reasons. I’m in two minds about this, because these are good reasons, but GIFs are really handy to be able to paste into HipChat and Slack and everywhere else.
  2. There is no real consensus concerning the pronunciation of GIF. The author of the format says JIF, a whole bunch of (vocal) other people say GIF.

This is our last week in this house. It was a beautiful base for our return to South Africa, but the time has come to move on to a new home and to new memories. Moving out of places is decidedly not my favourite state of being. I think I might still be traumatized by the experience of moving out of our Dutch hood.

This weekend, TPN and more of my friends were at Lowlands, my church. They’re still there, as I write this. I’ve been enjoying the experience through their photos and messages. You see, this is the first time in a number of years that I’m not there. My head, on the other hand, felt like it was more there than here this weekend. Nostalgia really is quite bitter-sweet.


I somehow only just now learnt that you can do this with Python:

x_inside = x_min <= x <= x_max

It turns out that in Python comparisons can be chained arbitrarily.

To those of you who’ve met me in person (that’s both of you I guess) it’s probably no surprise that my Myers–Briggs Type Indicator is ENTJ. Someone tweeted this page which defines hell for each of the MBTI types. Mine reads:

ENTJ – Somebody is wrong, and they’re directing a large group of people! You can’t do anything about it and will have to obey whatever inefficient policies they decide to implement.

I mention this, because this week I again fell into the trap, and broke my personal rule, of correcting someone who was wrong on the internet (it was about bicarbonate of soda and cancer). Of course this did not end well, although I managed to extract myself before it went completely off the rails.

It also made me think about why the internet, in spite of being one of the most wonderful things humankind has ever come up with, is so conducive to anti-social behaviour. You only have to take one look at the average comments section of a news site (news24, I’m looking at you), or at something even more toxic like this, to lose all hope in your fellow humans.

It turns out that we have a name for this: It’s called online disinhibition effect. It comes down to the fact that otherwise relatively normal people turn into anti-social gits when given anonymity (i.e. no consequences) and an audience. Penny Arcade dubbed this phenomenon the Greater Internet F*ckwad Theory and published this handy graphical guide. What I take from this, is that it is an especially good idea not to break the no-correcting-wrong-people-on-the-internet rule when the person in question is not posting under their real identity. Also, I really wish that we would grow up now.

Our week ended very much away from the digital world with a delightful and lazy Sunday lunch with great friends at Long Table restaurant on Haskell Vineyards just outside of Stellenbosch. The food was divine: Moroccan beef carpaccio starter, beautifully prepared Kob mains, followed by pecan nut praline cheese cake for dessert. As one does around these parts, the view was also something to drink in:


Ok kids, have yourselves a great week! I’ll hopefully see you on the other side.

Weekly Head Voices #98: Lemons.

This, the ninety eighth edition of the WHV, looks back at the week of Monday August 10 to Sunday August 16, 2015.

Today we took a brief walk up into the mountain, as one does around these parts. This is what False Bay looks like from the Helderberg Nature Reserve:


When life hands you lemons, build a battery

Genetic Offspring Unit (GOU) #1 had to do a show and tell at school, so I helped her to construct a battery from 4 lemons. Besides that because of this I got to refresh my own knowledge (can you remember exactly why a battery such as this works?!) we got to chat about molecules, atoms, protons, neutrons, electrons, atomic numbers and the periodic table.

The next day she quite coolly took the whole kit to school, proceeded to connect up the disassembled kit before the class, and got the little LED to switch on, all the while explaining in high-level 9-year-old-ish how it worked.

In case you’re wondering, the experiment looked like this:


With zinc-covered screws and heavy duty stripped copper wire, we got about 0.9V per lemon. There was enough current to light up a small 3V LED.

(Will GOU#1 one day become an engineer? Stay tuned to this blog for the next 10 years to find out!)

Taking a break from Facebook

One of my more interesting Facebook friends announced that she was taking a break from Facebook, because “this stuff is toxic and no good”.

This made me evaluate what I thought of FB at the moment.

Toxic is a strong word, but after thinking about this for a while, I have to admit that a large part of the time I spend on the site is probably not that good for my karma. The problem is that there are a whole bunch of friends I really would like to stay in contact with, but for the most part they are quite silent. The people that do pipe up the most on FB are people with some or other silly and/or misguided agenda.

Although I have learnt to stop correcting the infinite number of people who are wrong on the internet, I’m still reading their contributions, getting slightly worked up, formulating a response, and then resisting posting it, all of this a number of times per day.

To the question whether seeing the one or two positive and life-affirming posts is justified by a seemingly much larger number of the opposite, my response has also become to take a break from Facebook and to see for myself.

I’m not going to cancel my account, so I will receive notifications for example when people message me, but I’m just going to stop checking the site completely. I am also giving myself permission to post new WHV editions there now and then: It’s sometimes the best way to reach some of those silent but desirable FB friends I mentioned, because not all of them are subscribed to this blog. THAT’S A SUBTLE HINT SILENT BUT DESIRABLE FRIENDS.

(BTW, I’m almost 3 days in now, so far no problems. I’ll report back in future WHVs.)

The mind is a terrible thing to taste

This week I learned about fascinating sleeping brain research (that summary is from the NIH, also see this one by Science Magazine) that was published in 2013.

In short, when mice sleep, the area between their brain cells is temporarily increased by 60% (!!), and the cerebro-spinal fluid between the cells flows much more rapidly than when they’re awake. This rapid flow literally flushes out of the brain the toxins that build up during the waking hours. HOW COOL IS THAT?!

Toxins flushed out via bright blue channels between brain cells. Image from Science Mag summary linked above.

Going down one detail level, the researchers showed that the glial cells (the non-neuronal cells in the brain) control the flow of cerebro-spinal fluid through channels in their cell membranes. By using different coloured dyes, they showed that there was significantly more flow during sleeping than when awake, clearing out toxins twice as quickly.

This research took place in mice, but the researchers hypothesise that this same mechanism operates in humans, and are working on verifying that this is the case.

Original article full text: Sleep Drives Metabolite Clearance from the Adult Brain, Xie et al., 2013, Science.

This is the end my friends

Have a great week kids, and do remember to get your sleep!

Weekly Head Voices #97: Beerbow.

This, the ninety seventh edition of the WHV, looks back at the week of Monday August 3 to Sunday August 9, 2015.


  • John Scalzi (famous and successful SciFi author) describes how he works in this post on lifehacker. What I found really interesting was that when he’s working on a book or other project, he switches off the internet between 8 and noon.
  • I just discovered that Four Tet’s mom is South African-born.
  • This week my work time was divided between having to analyse someone else’s quite complex application and bits of their domain in order to implement new features on the one hand, and designing a new relational data representation for workflow provenance on the other. I perceived both of these activities as challenging, and hence (I think) my work week as very satisfying.
  • After the whole day programming at work, I often relax at home in the evenings by programming some more. I’ve noticed that the after-dinner beer (or two) make architectural and design-level work more challenging.
  • On the topic of programming for relaxation, this weekend I had the feeling that my longest-running side-project was finally getting off the ground, at least technically. When it grows up, it really wants to be a non-linear graphical personal knowledge management tool – the crazy and colourful glue linking together all of your digital stuff.
  • On the topic of beer, I made you a photo of my weekend craft beer (the Skeleton Coast IPA by Jack Black) with a rainbow in the background. I call it a beerbow:


Have a great week everyone!

P.S. I could not help adding that beerbow was partly inspired by the brainbow, a technique for making individual neurons (brain cells!) fluoresce with different colours. This technique has played a major role in the study of neural connections in the brain (this study is also called connectomics). Read more about the technique in its wikipedia article, and see the pretty examples I have now added to the top of this post!

P.P.S. I just saw that a book chapter called Visualization in Connectomics that we put on arxiv (FREE fulltext!!) whilst waiting for the rest of the book to happen, did eventually get published by Springer.

Weekly Head Voices #96: Never gonna give you up.

The week has resulted in a terribly nerdy list of bullets. READ AT YOUR OWN RISK! (there’s a beer recommendation or three at the end to compensate)

  • It turns out that the terrible Samsung trim bug which would eat all of your data, as discovered by Algolia, was a Linux kernel bug after all (now patched by Samsung) and that it would only affect RAID setups. Let’s hope there are no surprising new turning outs.
  • Found out that the fastest ADSL lines available at my new place are a whole 2 Mbit/s. We’ve called off the transaction and we’re now searching for a new house.
  • I’m joking. It was really shocking however to consider the world as seen through a 2 Mbit/s connection. Now it seems that I will soon be entering the wonderful world of 5 GHz wireless connectivity, which should give me a fast enough connection, at least until fibre is rolled out in the year 3047.
  • Started watching Mr Robot. I don’t normally do series, but the pilot was just that good. I like the story, I really like the socially very strangely adjusted hacker protagonist and I love the cinematography. Up to episode 3, I give it 4 out of 5 Linux Distributions!
  • Continued fighting with OSX to get it completely working with my Dvorak and Emacs keybindings, also in Java apps such as IntelliJ IDEA. Two weeks ago I mentioned karabiner as a solution to most of these problems. The final piece of the puzzle was unbinding keys like Alt+W (or Mod+W as Apple calls it) in ~/Library/KeyBindings/DefaultKeyBinding.dict to prevent OSX from turning it into a \(\Sigma\) (sigma); as everyone knows, M-w is the Emacs shortcut for copying the selected region! You can use this trick to prevent OSX from turning any of the other Mod combos into completely unwanted special characters. (My base dict file is that of Jacob Rus.)
  • I guess OSX only Just Works(tm) if your time is worth nothing. Err…
  • My first Kivy pull request, a fix for a Mac-bug (go figure), was recently merged into master. I’ve been using Kivy in the third or fourth generation of my current and probably longest running side project.
  • I’ve also been screencasting some of my night-time coding sessions using one of the more prominent livecoding sites (bonus points if you can find these sleep-inducing performances). It has been an interesting and strange experience programming with people watching over one’s shoulder as it were.
  • On Sunday, I ended up at the Root44 Market in Stellenbosch for another of those really terrible balmy winter days. I had so much fun in the sun, tasting Devil’s Peak First Light Golden Ale and their King’s Blockhouse IPA, and Stellenbrau’s Craven Lager, all from the tap, that I forgot to take a photo of the beautiful surroundings.

Have a beautiful week dear readers! Just remember, I’m never gonna give you up.

Weekly Head Voices #95: A wheel of good fortune.

The Cape Wheel with Table Mountain in the background.
  • NERD-ALERT: There are a whole bunch of awesome SciPy 2015 presentations online! I really liked these so far (due to good work and good presentation):
  • On Tuesday, I attended the monthly Helderberg Software Developers and Entrepreneurs meetup, which was a ridiculous amount of fun. As you might be able to see from the meetup page, there are mentions of wrestling. I’m still not sure which of the developer or entrepreneurial components contributed most to this occurrence (I observed, but chose to concentrate on beer and conversation), but my backyard anthropological senses are still tingling.
  • Sunday was one of those really difficult Winter days, so we spent it in the glorious sun at the V&A Waterfront. The highlight of the day was going up in the Cape Wheel, a beautiful engineering artifact with really stunning views:


Have a great week peeps!

P.S. If you’re on Android, disable auto-downloading of MMSes right now. There’s a new hack called stagefreight that’s possibly doing the rounds, and it’s a real doozy. With just your telephone number, an attacker can send you a specially crafted MMS and with that completely take over your phone (and hence your life) without your knowledge. For now, disable auto-downloading of MMSes. After that, if you receive an MMS, don’t touch it!