Zoom in to a chosen position. Due to their extremely clustered nature, structure of interest in an N-body simulation is often so small that it can not be seen when looking at the simulation as a whole. Color particles to display scalar fields. Examples of such fields are potential energy, or for SPH particles, density and temperature. Selection of a subset of the particles for display and analysis.
Regions of interest are generally small subsets of the simulation.
Following selected particles from one timestep to another. Finding cumulative properties of a collection of particles. This usually involves just a sum over the particles. The basic data structure is an array of particle structures. A single timestep is read into these arrays from a disk file.