integrators.cpp

Go to the documentation of this file.

 
void MultiStageIntegrator::SetIntegrator(std::string integrator) {
  if (integrator == "vl2") {
 
    // set number of stages and time coeff.
    nstages_ = 2;
  } else if (integrator == "rk3") {
 
    // set number of stages and time coeff.
    nstages_ = 3;
    stage_wghts_[0].sbeta = 0.0;
    stage_wghts_[0].ebeta = 1.0;
    stage_wghts_[0].delta = 1.0;
    stage_wghts_[0].gamma_1 = 0.0;
    stage_wghts_[0].gamma_2 = 1.0;
    stage_wghts_[0].gamma_3 = 0.0;
 
    stage_wghts_[1].sbeta = 1.0;
    stage_wghts_[1].ebeta = 0.5;
    stage_wghts_[1].delta = 0.0;
    stage_wghts_[1].gamma_1 = 0.25;
    stage_wghts_[1].gamma_2 = 0.75;
    stage_wghts_[1].gamma_3 = 0.0;
 
    stage_wghts_[2].sbeta = 0.5;
    stage_wghts_[2].ebeta = 1.0;
    stage_wghts_[2].delta = 0.0;
    stage_wghts_[2].gamma_1 = 2. / 3.;
    stage_wghts_[2].gamma_2 = 1. / 3.;
    stage_wghts_[2].gamma_3 = 0.0;
 
    stage_wghts_[0].beta = 1.0;
    stage_wghts_[1].beta = 0.25;
    stage_wghts_[2].beta = 2. / 3.;
  };