Rtrack uses a library for fast manipulation of spatial goemetries (which allows it to efficiently collect metrics such as ‘time in zone’ for even very complex arenas). This library is called GEOS and is used by the R package rgeos. On some systems (particularly Mac OS X), this library may need to be installed manually first (the library is not part of R).

Installation of GEOS on OS X

The easiest way to do this on Mac OS X is to install it using ‘homebrew’ This is a package manager which allows all sorts of useful tools to be installed on Mac. Install homebrew following the instructions in the link above and then install GEOS by pasting the following command in the Terminal:

brew install geos

This only needs to be done once and then the installation of Rtrack can be successfully carried out.

Why so complicated?

There are some alternative approaches to using GEOS, but in my tests so far, they are around 10x slower. I want you to get your work done quickly. On most systems, pre-built versions of GEOS are available so most people will never need this additional installation step. Future versions of Rtrack will continue to optimise the speed/simplicity balance.