Panel a: relative distribution of disc radii at the end of the simulations (1 Myr) for our Trap30 simulations. Brown corresponds to face-on accretion (FA), including ram pressure stripping, and green to truncation due to dynamical encounters (DE). The distribution is based on all the disc radii in the ten simulations we have performed with these parameters. The solid and dotted vertical lines in the corresponding colour indicate the median and mean disc radius, respectively. Panel b: the standard deviation of the radius distribution versus the median disc radius for the IM simulations. The colours correspond to the same process. Squares indicate the simulations with N_∗ = 2045, diamonds the simulations with N_∗ = 680, triangles the simulations with N_∗ = 230 and circles the simulations with N_∗ = 70.