An algorithm is implemented for the computation of inertial manifolds to ar
bitrary accuracy. It is applied to the Kuramoto-Sivashinsky equation to rec
over the high wave number components of elements on the global attractor. T
he computational results demonstrate that this algorithm is significantly m
ore accurate than previous methods, when compared after just a few iteratio
ns. An essential feature of the algorithm is that it does not require that
the entire manifold be constructed. Hence the algorithm is particularly sui
ted for computing trajectories on the manifold, and its computational compl
exity is independent of the dimension.