Quaternions are essentially magic. With just four numbers, they can describe the position and orientation of an object in space. For example, the rotation of an object about one axis. Consecutive rotations can also be described by a quaternion. There are many explainer articles which help to understand quaternions and their uses (they are used […]
Tag: Igor
Turn A Square: generative aRt
A while back I visited Artistes & Robots in Paris. Part of the exhibition was on the origins of computer-based art. Nowadays this is referred to as generative art, where computers generate artwork according to rules specified by the programmer. I wanted to emulate some of the early generative artwork I saw there, using R. Some […]
Small Talk: How big is your lab?
I really dislike being asked “how big is your lab?”. The question usually arises at scientific meetings when you are chatting to someone during a break. Small talk can lead to some banal questions being asked, and that’s fine, but when this question is asked seriously, the person asking really just wants to compare themselves […]
My Blank Pages VI: Programming in Igor Pro
It has been a long time since I wrote a book review. A few months ago I read on IgorExchange that Martin Schmid had written a book about programming Igor. I snapped up a copy. I’m a competent Igor programmer but I was hoping that this book would be useful for lab members that want […]
Cloud Eleven: A cloud-based code sharing solution for IgorPro
This post is something of a “how to” guide. The problem is how can you share code with a small team and keep it up-to-date? For ImageJ, the solution is simple. You can make an ImageJ update site and then push any updated code to the user when they startup ImageJ. For IgorPro, there is […]
Esoteric Circle
Many projects in the lab involve quantifying circular objects. Microtubules, vesicles and so on are approximately circular in cross section. This quick post is about how to find the diameter of these objects using a computer. So how do you measure the diameter of an object that is approximately circular? Well, if it was circular […]
Parallel lines: new paper on modelling mitotic microtubules in 3D
We have a new paper out! You can access it here. The people This paper really was a team effort. Faye Nixon and Tom Honnor are joint-first authors. Faye did most of the experimental work in the final months of her PhD and Tom came up with the idea for the mathematical modelling and helped to […]
Adventures in Code V: making a map of Igor functions
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 […]
Realm of Chaos
Caution: this post is for nerds only. I watched this numberphile video last night and was fascinated by the point pattern that was created in it. I thought I would quickly program my own version to recreate it and then look at patterns made by more points. I didn’t realise until afterwards that there is actually […]
Elevation: accuracy of a Garmin Edge 800 GPS device
I use a Garmin 800 GPS device to log my cycling activity. including my commutes. Since I have now built up nearly 4 years of cycling the same route, I had a good dataset to look at how accurate the device is. I wrote some code to import all of the rides tagged with commute […]