A numerical study of the nonlinear wave solutions of the Rosenau-Pikovsky
K(cos) equation is presented. This equation supports at least two kind of
solitary waves with compact support: compactons of varying amplitude and speed,
both bounded, and kovatons which have the maximum compacton amplitude, but
arbitrary width. A new Pad\'e numerical method is used to simulate the
propagation and, with small artificial viscosity added, the interaction between
these kind of solitary waves. Several numerically induced phenomena that appear
while propagating these compact travelling waves are discussed quantitatively,
including self-similar forward and backward wavepackets. The collisions of
compactons and kovatons show new phenomena such as the inversion of compactons
and the generation of pairwise ripples decomposing into small
compacton-anticompacton pairs