Measuring rotation sets of coupled oscillators

We present a simple way of measuring the rotation set of a system of coupled oscillators. The data is scanned to look for approximate periodic orbits and the rotation vectors of these periodic orbits are computed. For systems in the presence of low level noise, the convex hull of the computed points corresponds to the chain transitive rotation set provided no 'false' periodic orbits are found. We test our method on the sine-circle map, the Kim-Ostlund torus map and a system of three coupled electronic oscillators, and discuss the effect of noise on the results.