TimeForwardEuler.c File Reference

Forward Euler method. More...

#include <basic.h>
#include <arrayfunctions.h>
#include <simulation_object.h>
#include <timeintegration.h>

Go to the source code of this file.

Functions
int	TimeForwardEuler (void *ts)

Detailed Description

Forward Euler method.

Author

Debojyoti Ghosh

Definition in file TimeForwardEuler.c.

Function Documentation

int TimeForwardEuler

(

void *

ts

)

Advance the ODE given by

\begin{equation} \frac{d{\bf u}}{dt} = {\bf F} \left({\bf u}\right) \end{equation}

by one time step of size HyPar::dt using the forward Euler method given by

\begin{equation} {\bf u}^{n+1} = {\bf u}^n + \Delta t {\bf F}\left( {\bf u}^n \right) \end{equation}

where the superscript represents the time level, \(\Delta t\) is the time step size HyPar::dt, and \({\bf F}\left({\bf u}\right)\) is computed by TimeIntegration::RHSFunction.

Parameters

ts	Time integrator object of type TimeIntegration

Definition at line 25 of file TimeForwardEuler.c.

{
  TimeIntegration* TS = (TimeIntegration*) ts;
  SimulationObject* sim = (SimulationObject*) TS->simulation;
  int ns, nsims = TS->nsims;
  _DECLARE_IERR_;

  for (ns = 0; ns < nsims; ns++) {

    HyPar* solver = &(sim[ns].solver);
    MPIVariables* mpi = &(sim[ns].mpi);

    double* rhs = TS->rhs + TS->u_offsets[ns];
  
    /* Evaluate right-hand side */
    IERR TS->RHSFunction( rhs,
                          solver->u,
                          solver,
                          mpi,
                          TS->waqt  );   CHECKERR(ierr);
  
    /* update solution */
    _ArrayAXPY_(  rhs,
                  TS->dt,
                  solver->u,
                  TS->u_sizes[ns] );

    _ArrayScaleCopy1D_( solver->StageBoundaryIntegral,
                        TS->dt,
                        solver->StepBoundaryIntegral,
                        TS->bf_sizes[ns] );
  }

  return(0);
}