I'm David Llewellyn-Jones and this is my homepage. I'm a software engineer at Jolla, who's also interested in programming, security, privacy and graphics. I occasionally crave adventure and a good thunderstorm. You might be interested in my software, my research or my random musings.

Want to know more about me? Here's a personality sketch written by a psychologist when I was in school.

“David is of high intelligence, although lacking in true creativity. He has a need for order and clarity, and for neat and tidy systems in which every detail finds its appropriate place. His writing is rather dull and mechanical, occasionally enlivened by somewhat corny puns and by flashes of imagination of the sci-fi type. He has a strong drive for competence. He seems to have little feel and little sympathy for other people and does not enjoy interacting with others. Self-centered, he nonetheless has a deep moral sense.”

Wow. Harsh. But disturbingly accurate.

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3 Dec 2019 : Graphs of Waste, Part 4 #
The final part of my Graphs of Waste series is now up on my blog. It looks at some of the potentialy pitfalls of using the histocurves developed through the first three parts. If you read the series, I hope you enjoyed it, and... well done!
30 Nov 2019 : Waste data #
Staying on a pretty even keel this week with my waste output. Just lightly up on last week (more card, for some reason) but still below average.
26 Nov 2019 : Graphs of Waste, Part 3 #
The third part in my series on histograms is now available on my blog, entitled "A Continuously Differentiable Histogram Approach". In it we take a look at now to create a curved histogram (a histocurve!) to replace the column and line based approaches from parts 1 and 2.
24 Nov 2019 : Waste data #
New waste data is up on my waste page. It seems to have been a pretty average week this week, in spite of me having to throw away a heavy dose of my unpleasant Turkish Delight ("Turkish Disgust"?). Slightly below average with paper down (due to the postal strike in Finland). General waste is down and plastic is up, but mostly because I'm getting better at sorting them: combined they're about average. Don't forget if this is somehow interesting to you, you might find the series on drawing these waste graphs interesting. Part 1 and part 2 are up on my blog.
19 Nov 2019 : Sailfish Backup and Restore from Xperia XA2 to Xperia 10 #
If you're thinking of upgrading your Sailfish OS phone to one of the nice new Xperia 10 devices, chances are you'll want to copy your data from your old phone to your new one. Having just been through the exprience, I've posted some notes on what I had to do on my blog. The might be useful or interesting to some people, including future me.