Universal approximation by systems of hill functions
In this paper, our attention is concentrated on the GMRES method for the solution of the system of linear algebraic equations with a nonsymmetric matrix. We perform pre-iterations before starting GMRES and put for the initial approximation in GMRES. We derive an upper estimate for the norm of the error vector in dependence on the th powers of eigenvalues of the matrix . Further we study under what eigenvalues lay-out this upper estimate is the best one. The estimate shows and numerical...
We present a novel, cell-local shock detector for use with discontinuous Galerkin (DG) methods. The output of this detector is a reliably scaled, element-wise smoothness estimate which is suited as a control input to a shock capture mechanism. Using an artificial viscosity in the latter role, we obtain a DG scheme for the numerical solution of nonlinear systems of conservation laws. Building on work by Persson and Peraire, we thoroughly justify the...