/** * @ingroup VanDerPol */ double run_vdp_sdc(const size_t nsteps, const double dt, const size_t nnodes, const size_t niters, const double nu, const double x0, const double y0, const quadrature::QuadratureType nodetype) { SDC<> sdc; auto quad = quadrature::quadrature_factory(nnodes, nodetype); // van der Pol oscillator (as first order system) has two components auto factory = make_shared<encap::VectorFactory<double>>(2); // input is parameter nu and initial values for position and velocity auto sweeper = make_shared<VdpSweeper<>>(nu, x0, y0); sweeper->set_quadrature(quad); sweeper->set_factory(factory); sdc.add_level(sweeper); // Final time Tend = dt*nsteps sdc.set_duration(0.0, dt*nsteps, dt, niters); sdc.setup(); auto q0 = sweeper->get_start_state(); sweeper->exact(q0, 0.0); sdc.run(); return sweeper->get_errors(); }
/** * Advection/diffusion example using an encapsulated IMEX sweeper. * * This example uses a vanilla SDC sweeper. * * @ingroup AdvectionDiffusion */ error_map run_vanilla_sdc(double abs_residual_tol, double rel_residual_tol=0.0) { SDC<> sdc; auto const nnodes = config::get_value<size_t>("num_nodes", 3); auto const ndofs = config::get_value<size_t>("spatial_dofs", 64); auto const quad_type = \ config::get_value<quadrature::QuadratureType>("nodes_type", quadrature::QuadratureType::GaussLegendre); auto quad = quadrature::quadrature_factory(nnodes, quad_type); auto factory = make_shared<encap::VectorFactory<double>>(ndofs); auto sweeper = make_shared<AdvectionDiffusionSweeper<>>(ndofs); sweeper->set_quadrature(quad); sweeper->set_factory(factory); sweeper->set_residual_tolerances(abs_residual_tol, rel_residual_tol); sdc.add_level(sweeper); sdc.set_duration(0.0, 4*0.01, 0.01, 4); sdc.set_options(); sdc.setup(); auto q0 = sweeper->get_start_state(); sweeper->exact(q0, 0.0); sdc.run(); fftw_cleanup(); return sweeper->get_errors(); }