Here is a quick method for checking parity between two directories. Let’s say we have two directories dir1 and dir2. They are large and have thousands of files and subdirectories. How can we check that they have the same contents? I found myself in this situation recently during a server migration.

The Retropie project is a wonderful way to play retro games on a Raspberry Pi (see previous post). A number of handheld units are available to make a convincing retro gaming experience. One of these is the Retroflag GPi case, modelled on Nintendo’s Game Boy. It’s possible to order one of these pre-built and even loaded with games, but where is the fun in that? Here is a quick guide to building one.

I have a long-running project to make timelapse movies using a Raspberry Pi Zero with camera module. I’m capturing a countryside view and have images for two years. The uptime on the Pi is seriously impressive, but nonetheless I wanted to upgrade the Pi so that it would send me updates of how it’s going, so that I would know if it image capture had failed. Here is my solution.

I was working on a figure in Adobe Illustrator today. The ai file had 32 embedded TIFF files (we tend to embed images rather than linking them for portability reasons). I wanted to change all of the images, but to do this I needed to know where the originals were.

A short tech-tip this week. How can you find a line of code somewhere on your computer? I often find that I need to write a line of code and I can’t remember the exact syntax. To add to the frustration, I can remember writing a similar line before, but can’t remember in which file it was (or for what project, or even when it might’ve been). How can I quickly track that line down? Today I needed to write a LoadWave command in Igor.

Time for an update to a previous post. For the past few years, I have been using an automated process to track citations to my lab’s work on Google Scholar (details of how to set this up are at the end of this post). Due to the nature of how Google Scholar tracks citations, it means that citations get added (hooray!) but might be removed (booo!). Using a daily scrape of the data it is possible to watch this happening.

This is a quick “how to” post. There is a licensed version of PyMol (MacPyMol) available, but the open source version can be installed on a Mac free of charge. The official page has a guide, which is not terribly detailed, and I found this excellent guide which is unfortunately out-of-date.

This is the first post at quantixed about Raspberry Pi computing. Pi Zero is a minimalist Raspberry Pi that can be coupled to a camera. With this little rig, you can make time-lapse footage amongst other things. I’ve set up a couple of these now. One was to make a time-lapse movie of some plants growing through a plastic maze. The results were pretty good and I thought I’d upload the video and a brief how-to guide.

I’ve generated a lot of code for IgorPro. Keeping track of it all has got easier since I started using GitHub – even so – I have found myself writing something only to discover that I had previously written the same thing. I was thinking that it would be good to make a list of all functions that I’ve written to locate long lost functions.