  Several techniques have appeared in the literatuare to solve the equations of
time-dependent density functional theory. We compare the efficiency of
different methods based on mesh representations of the wave function (direct
and Fourier space), taking as a test case the calculation of the surface
plasmon in the cluster Na_8. For smaller systems, the methods have comparable
efficiency. For large systems the direct time method has a decided advantage in
computer storage requirements. It is also more economical on arithmetic
operations, but is not as suited for parallel computing as the methods based on
a frequency representation.
