## Snakes and ladders: end-game rules

My 5-year-old son is mysteriously keen on a Snakes And Ladders game we have, but there is often some discussion about what the ending rule should be. The winner is definitely the person who lands on square 100 first, but what to do if you roll a number which would take you past square 100? There are two rules we play: You win. You bounce back off the end of the board. E.g., from square 98, a roll of 6 would take you: 99, 100, 99, 98, 97, 96. Photo © Nick Fedele. CC-BY-SA-2.0 Empirically, the game takes way longer if you play the ‘bounce’ rule than if you play the ‘win’ rule. But how much longer, on average? It turns out that

## Simulating a laser-based image projector

Some experiments to explore the ideas used by an image projector using the Fourier transform as its underlying mechanism.

## Counting sums of triangular and square numbers

The number of ways of writing an integer as the sum of a square number and twice a triangular number is the same as the number of ways of writing it as the sum of two triangular numbers.

## New video: stop-motion with sound!

A stop-motion animation with a bit of a story — one friend goes to visit another friend. And also sound! Animators: Jude and Zach Voice actors: Jude and Zach Camera operator: Meg Post-production: Ben (To put it together, I used Openshot again, but found it buggy and crashy this time, and the freeze-frame effect was quite fiddly to use. I also looked at kdenlive, which was in many ways much better but its freeze-frame effect didn’t seem to work if you used a clip more than once.)

## Encoding video for Archos Vision 14

© 2008, Blender Foundation : CC BY 3.0www.bigbuckbunny.org The kids had taken a few videos which they wanted to put onto their Archos Vision 14 portable media players, but the supplied software is Windows-only and wouldn’t run successfully under Wine. The example movie on the device (Big Buck Bunny) had in its metadata a comment that it had been encoded with mencoder, so I thought there was a reasonable chance that Archos’s clunky-GUI’d software just called out to mencoder to do the actual work. Running Archos’s AVIConverter on a real Windows XP machine and watching via Process Explorer revealed that this was the case. Grabbing the command-line and trying it under Linux worked: mencoder -noodml \ input-file.avi \ -of avi -o output-file.avi

## Most cliched adjectives and nouns

Which adjectives are most commonly paired with only a few nouns? Which nouns are most commonly paired with only a few adjectives? Combining the Google N-Gram data with a parts-of-speech database yields some answers.

## Meg’s book: Laura’s Troubles

For Christmas, my daughter Meg gave me a hardback book which she had made herself (with help from Bear), using one of the many on-line design-your-own-book outfits, Pixum. Pixum provides a Linux version of their book-design software, which is notable and encouraging. But I could see no obvious way of exporting to PDF, and wanted to send a soft copy to my parents. The file format used by Pixum’s software is XML, and it wasn’t too tricky to work out enough of the details to produce a reasonable facsimile in PDF, using various Python packages (ElementTree, Python Imaging Library, BeautifulSoup, tinycss, ReportLab’s Pdf Library). I was not able to get the text positioning to exactly match the original printed version,

## Braille in National Aquatic Centre lifts

I was wondering about the Braille signs in the lifts at Dublin’s National Aquatic Centre, and it turns out they are in German (courtesy of the Wikipedia entries on German braille and Braille patterns in Unicode): Open doors ⠞⠳⠗⠀⠡⠋ Tür auf Close doors ⠞⠳⠗⠀⠵⠥ Tür zu Alarm ⠝⠕⠞⠗⠥⠋ Notruf Curious. See also this xkcd (thanks to Oliver Nash for the pointer).