A comment from a referee led me to find a method to describe curvature of membranes. This is a quick write-up of our solution. I couldn’t find a solution readily available in Fiji, so I created one using a combination of Fiji for tracing the curvature and IgorPro to do the fitting. If there is any interest I can convert this code into an all-Fiji routine. The code is simple and a gist is available here.

A colleague sent me a coding challenge. This is a short post to describe how I tackled it. Edit: a follow-up post is here.

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.

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 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 to you in some way.

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 to learn. Learning Igor – like most IDEs or programming languages – is tough going.

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 no equivalent. Typically I send ipf files to someone and they run the code, but I have to resend them whenever there’s an update.

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 you would measure the distance from one edge to the other, crossing the centre of the object.

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 rewrite our analysis method in R. Other people helped in lots of ways.

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.