Projections of configuration, angle, frequency, and action space at t = 0 (top panels) and t = 3.5 Gyr (bottom panels) for an N-body stream evolved in a spherical NFW potential. The first column shows the projection of the stream on the orbital plane of the progenitor. Particles still bound to the progenitor are plotted in red. In the third column we have overlaid the distribution of frequencies at t = 10 Gyr in grey. In the panels on the right, we also show the final distribution of actions at t = 10 Gyr in grey. The actions, angles and frequencies have been centred on the coordinates of the centre of mass of the progenitor and the colours represent the energy gradient.