brainwagon

The ESP8266 is an amazing little processor: cheap and capable and (most interestingly) WiFi enabled. I have some of the older “nodemcu” boards that I got for about $7 each, but there are newer alternatives that include up to 4M of flash memory, and a variety of interesting form factors. I noticed that WeMos was […]

I use ffmpeg to add some information overlays to the videos that I often upload to YouTube. I’ve documented these before, but I had a problem that arose from time to time that I never figured out: occasionally my encodes would seemingly just go on forever, and never terminate. I discovered today that this was […]

Eek! I was getting a bit impatient with my dorodango, so I decided to leave it out in the open air when I went to work today so I could let it dry out a bit. I returned to it having dry cracks! Note to anyone attempting this: don’t be impatient. Let it dry out […]

On Sunday, I started a new project which on the face of it, seems like an enormous waste of time, but if you’ve been reading my blog for any period of time, you know that wasting time is pretty much the bread and butter of my online presence, so here we go. I’ve started work […]

Last year, I bodged together a motion detecting camera to photograph hummingbirds at my hummingbird feeder. But it was always a temporary hack. We had some difficulty with the ants that discovered the feeder, and we discontinued the experiment. I had a post that I could hang some feeders from, and decided to fill a […]

Long time readers of this blog might remember that I received a Gameduino board designed by James Bowman. I used it to construct ANGST, an Arduino and Gameduino satellite tracking project. James did all the heavy lifting: the Gameduino uses a Xilinx FPGA to implement an Arduino shield that can generate graphics and sounds. To […]

Joel Grus blogged about a job interview where he was asked about the ridiculous Fizz Buzz question that apparently some companies use to weed out complete frauds from their job interview process. The task is to create a program which prints the numbers from 1 to 100, but where all numbers which are a multiple […]

I just recently found out about the /r/showerthoughts subreddit, where people vote on pithy sayings. I thought this might be a fun thing to have to replace the aging and relatively static “fortune” file that I use. I used the Python “PRAW” library to fetch the top entry for the day, and then optionally pass […]

The other day I mentioned that generating random Latin squares was a bit more complicated than I thought, and that an algorithm by Jacobson and Matthews was the way that people typically did it. I worked up this implementation based on a couple of different descriptions of the algorithm (the original paper was behind a […]

My last post dealt with a solver for KenKen puzzles. Once you have one of those, then the obvious thing to work on next (in your copious spare time) is a generator for KenKen puzzles. It didn’t seem too hard. You’d begin by generating a random Latin square, then divide it up into “cages”, assign […]

Lately, my lunch hours have been spent working on the NYT Crossword with my lunch companion Tom. While I find that the Thursday crosswords are often beyond my ability to do in the allotted time, between the two of us, more often than not we manage to plow through them. Slowly over time, we’ve begun […]

Just a pointer to a cool project which appeared on Hackaday: a solar powered FPV plane that can fly forever (or at least until the sun goes down). Pretty spiffy! The comments show a link to this solar powered plane developed at ETH: It was in the air for 81.5 hours, and had a continuous […]

I’ve been meaning to write down this story for a while, because it represents a time when I was booed away from a microphone by a crowd of two thousand people, and I always think that stories like this are fun. Back in 1996, I attended SIGGRAPH in New Orleans. I remember flying out early […]

Backtracking is a better technique, obviously. The version from earlier today was actually not very clever, and took half an hour to find the 73,712 solutions to the 13×13 checkerboard. This version is less code (just 91 lines, compared to 107 for yesterdays) and finds all the 13×13 solutions in just 2.5 seconds (a speed […]