TimeGetAuxSolutions.c File Reference

Returns any "auxiliary" solutions. More...

#include <stdio.h>
#include <string.h>
#include <hypar.h>
#include <timeintegration.h>

Go to the source code of this file.

Functions
int	TimeGetAuxSolutions (int *N, double **uaux, void *s, int nu, int ns)

Detailed Description

Returns any "auxiliary" solutions.

Author

Debojyoti Ghosh

Definition in file TimeGetAuxSolutions.c.

Function Documentation

TimeGetAuxSolutions()

int TimeGetAuxSolutions	(	int *	N,
		double **	uaux,
		void *	s,
		int	nu,
		int	ns
	)

Return auxiliary solution: Some time integrators may have the concept of auxiliary solutions that they evolve along with the main solution HyPar::u (these may be used for error estimation, for example). This function returns a pointer to such an auxiliary solution. Note that the auxiliary solution has the same dimensions and array layout as the main solution.

• Call with the final argument n less than 0 to get the total number of auxiliary solutions (this value will be stored in the argument N at exit).
• Call with the final argument n less than or equal to zero to get the n-th auxiliary solution (the argument uaux will point to this at exit).

Note that auxiliary solutions are numbered in the C convention: 0,1,...,N-1.

Time integration methods which use auxiliary solutions currently implemented:

• General Linear Methods with Global Error Estimators (GLM-GEE - _GLM_GEE_) (see TimeGLMGEE(), TimeGLMGEEInitialize() ).

Parameters

N	Number of auxiliary solutions
uaux	Pointer to the array holding the auxiliary solution
s	Solver object of type HyPar
nu	Index of the auxiliary solution to return
ns	Index of the simulation domain of which the auxiliary solution to return

Definition at line 29 of file TimeGetAuxSolutions.c.

{
  HyPar           *solver = (HyPar*) s;
  TimeIntegration *TS     = (TimeIntegration*) solver->time_integrator;

  if (nu >= 0) {
    if (!strcmp(solver->time_scheme,_GLM_GEE_)) {
      GLMGEEParameters *params = (GLMGEEParameters*) solver->msti;
      *uaux = (TS->U[params->r+nu] + TS->u_offsets[ns]);
    }
  } else {
    if (!TS) *N = 0;
    else {
      if (!strcmp(solver->time_scheme,_GLM_GEE_)) {
        GLMGEEParameters *params = (GLMGEEParameters*) solver->msti;
        *N = params->r - 1;
      } else *N = 0;
    }
  }

  return(0);
}