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|
/*@@
@file SetTime.c
@date Mon May 20 09:45:45 2002
@author Ian Hawke
@desc
Sets the time and dt depending on the ODE method and
position in the loop.
@enddesc
@version $Header$
@@*/
#include <stdlib.h>
#include "cctk.h"
#include "cctk_Arguments.h"
#include "cctk_Parameters.h"
static const char *rcsid = "$Header$";
CCTK_FILEVERSION(CactusBase_MoL_SetTime_c);
/* #define MOLDEBUG 1 */
/********************************************************************
********************* Local Data Types ***********************
********************************************************************/
/********************************************************************
********************* Local Routine Prototypes *********************
********************************************************************/
/********************************************************************
***************** Scheduled Routine Prototypes *********************
********************************************************************/
void MoL_SetTime(CCTK_ARGUMENTS);
void MoL_ResetTime(CCTK_ARGUMENTS);
void MoL_ResetDeltaTime(CCTK_ARGUMENTS);
/********************************************************************
********************* Other Routine Prototypes *********************
********************************************************************/
/********************************************************************
********************* Local Data *****************************
********************************************************************/
/* RK45 Fehlberg coefficients */
static const CCTK_REAL alpha_array_F[6] = {
0.0,
1.0/4.0,
3.0/8.0,
12.0/13.0,
1.0,
1.0/2.0,
};
/* RK45 Cash-Karp coefficients */
static const CCTK_REAL alpha_array_CK[6] = {
0.0,
1.0/5.0,
3.0/10.0,
3.0/5.0,
1.0,
7.0/8.0,
};
/* RK65 coefficients */
static const CCTK_REAL alpha_array65[8] = {
0.0,
1.0/10.0,
2.0/9.0,
3.0/7.0,
3.0/5.0,
4.0/5.0,
1.0,
1.0
};
/* RK87 coefficients */
static const CCTK_REAL alpha_array87[13] = {
0.0,
1.0/18.0,
1.0/12.0,
1.0/8.0,
5.0/16.0,
3.0/8.0,
59.0/400.0,
93.0/200.0,
5490023248.0/9719169821.0,
13.0/20.0,
1201146811.0/1299019798.0,
1.0,
1.0
};
/********************************************************************
********************* External Routines **********************
********************************************************************/
/*@@
@routine MoL_SetTime
@date Mon May 20 09:48:55 2002
@author Ian Hawke
@desc
Sets the time and timestep before the MoL evolution loop starts.
@enddesc
@calls
@calledby
@history
@endhistory
@@*/
void MoL_SetTime(CCTK_ARGUMENTS)
{
DECLARE_CCTK_ARGUMENTS;
DECLARE_CCTK_PARAMETERS;
CCTK_REAL beta;
if (adaptive_stepsize && ! CCTK_EQUALS(verbose, "none"))
{
CCTK_VInfo (CCTK_THORNSTRING, "Integrating from %g to %g with step size %g",
(double)(cctkGH->cctk_time - cctkGH->cctk_delta_time),
(double)cctkGH->cctk_time,
(double)cctkGH->cctk_delta_time);
}
*Original_Time = cctkGH->cctk_time;
*Original_Delta_Time = cctkGH->cctk_delta_time;
cctkGH->cctk_time -= cctkGH->cctk_delta_time / cctkGH->cctk_timefac;
if (CCTK_EQUALS(ODE_Method,"ICN"))
{
cctkGH->cctk_delta_time = 0.5*(*Original_Delta_Time);
}
else if (CCTK_EQUALS(ODE_Method,"ICN-avg"))
{
cctkGH->cctk_delta_time = *Original_Delta_Time;
}
else if (CCTK_EQUALS(ODE_Method,"Generic"))
{
beta = RKBetaCoefficients[0];
cctkGH->cctk_delta_time = beta*(*Original_Delta_Time);
}
}
/*@@
@routine MoL_ResetTime
@date Mon May 20 09:49:41 2002
@author Ian Hawke
@desc
Sets the time during the MoL evolution loop.
At the last time all methods should end up with the original
values for time and timestep.
@enddesc
@calls
@calledby
@history
@endhistory
@@*/
void MoL_ResetTime(CCTK_ARGUMENTS)
{
DECLARE_CCTK_ARGUMENTS;
DECLARE_CCTK_PARAMETERS;
CCTK_REAL *previous_times;
CCTK_INT alphaindex, i, j;
previous_times = (CCTK_REAL*)malloc(MoL_Intermediate_Steps*sizeof(CCTK_REAL));
if (!previous_times)
{
CCTK_WARN(0,"Failed to allocate memory for very small array!");
}
if (*MoL_Intermediate_Step == 0)
{
cctkGH->cctk_time = (*Original_Time);
}
else if (CCTK_EQUALS(ODE_Method,"ICN"))
{
cctkGH->cctk_time = (*Original_Time) -
0.5*(*Original_Delta_Time)/cctkGH->cctk_timefac;
}
else if (CCTK_EQUALS(ODE_Method,"ICN-avg"))
{
cctkGH->cctk_time = (*Original_Time);
}
else if (CCTK_EQUALS(ODE_Method,"Generic"))
{
previous_times[0] = (*Original_Time) -
(*Original_Delta_Time)/cctkGH->cctk_timefac;
for (i = MoL_Intermediate_Steps - 1; i > *MoL_Intermediate_Step - 1; i--)
{
previous_times[MoL_Intermediate_Steps - i] =
RKBetaCoefficients[MoL_Intermediate_Steps - i - 1] *
(*Original_Delta_Time)/cctkGH->cctk_timefac;
for (j = MoL_Intermediate_Steps; j > i; j--)
{
alphaindex = (MoL_Intermediate_Steps - i - 1) *
MoL_Intermediate_Steps + MoL_Intermediate_Steps - j;
previous_times[MoL_Intermediate_Steps - i] +=
RKAlphaCoefficients[alphaindex] *
previous_times[MoL_Intermediate_Steps - j];
#ifdef MOLDEBUG
printf("i %d j %d is %d index %d t %g dt %g alpha %g beta %g\n",
i, j, MoL_Intermediate_Steps, alphaindex,
previous_times[MoL_Intermediate_Steps - i],
(*Original_Delta_Time)/cctkGH->cctk_timefac,
RKAlphaCoefficients[alphaindex],
RKBetaCoefficients[MoL_Intermediate_Steps - i - 1]);
#endif
}
}
#ifdef MOLDEBUG
printf("MoL says the previous times are ");
for (i = 0; i < MoL_Intermediate_Steps - *MoL_Intermediate_Step
+ 1; i++)
{
printf("%g ", previous_times[i]);
}
printf("\n");
#endif
cctkGH->cctk_time = previous_times[MoL_Intermediate_Steps -
*MoL_Intermediate_Step];
}
else if (CCTK_EQUALS(ODE_Method,"RK2"))
{
if (*MoL_Intermediate_Step == 1)
{
cctkGH->cctk_time = (*Original_Time);
}
}
else if (CCTK_EQUALS(ODE_Method,"RK3"))
{
if (*MoL_Intermediate_Step == 2)
{
cctkGH->cctk_time = (*Original_Time);
}
else if (*MoL_Intermediate_Step == 1)
{
cctkGH->cctk_time = (*Original_Time) -
0.5*(*Original_Delta_Time)/cctkGH->cctk_timefac;
}
}
else if (CCTK_EQUALS(ODE_Method,"RK4"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
CCTK_REAL dt = (*Original_Delta_Time)/cctkGH->cctk_timefac;
switch (substep)
{
case 1:
case 2:
dt *= 0.5;
break;
default:
dt = 0;
}
cctkGH->cctk_time = (*Original_Time) - dt;
}
else if (CCTK_EQUALS(ODE_Method,"RK45") || CCTK_EQUALS(ODE_Method,"RK45CK"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
const CCTK_REAL * alpha_array;
if (CCTK_EQUALS(ODE_Method, "RK45"))
{
alpha_array = alpha_array_F;
}
else if (CCTK_EQUALS(ODE_Method, "RK45CK"))
{
alpha_array = alpha_array_CK;
}
else
{
CCTK_WARN (0, "internal error");
/* Avoid compiler warning */
alpha_array = NULL;
}
cctkGH->cctk_time
= ((* Original_Time)
+ ((alpha_array[substep] - 1)
* (* Original_Delta_Time) / cctkGH->cctk_timefac));
}
else if (CCTK_EQUALS(ODE_Method,"RK65"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
cctkGH->cctk_time
= ((* Original_Time)
+ ((alpha_array65[substep] - 1)
* (* Original_Delta_Time) / cctkGH->cctk_timefac));
}
else if (CCTK_EQUALS(ODE_Method,"RK87"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
cctkGH->cctk_time
= ((* Original_Time)
+ ((alpha_array87[substep] - 1)
* (* Original_Delta_Time) / cctkGH->cctk_timefac));
}
else if (CCTK_EQUALS(ODE_Method,"AB"))
{
CCTK_WARN (0, "internal error");
}
else if (CCTK_EQUALS(ODE_Method,"RK2-MR-2:1"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
CCTK_REAL dt = (*Original_Delta_Time)/cctkGH->cctk_timefac;
switch (substep)
{
case 1:
case 2:
dt *= 0.5;
break;
default:
dt = 0;
}
cctkGH->cctk_time = (*Original_Time) - dt;
}
else if (CCTK_EQUALS(ODE_Method,"RK4-MR-2:1"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
CCTK_REAL dt = (*Original_Delta_Time)/cctkGH->cctk_timefac;
switch (substep)
{
case 1:
case 2:
dt *= 3.0/4.0;
break;
case 3:
case 4:
case 5:
dt *= 1.0/2.0;
break;
case 6:
case 7:
dt *= 1.0/4.0;
break;
default:
dt = 0;
}
cctkGH->cctk_time = (*Original_Time) - dt;
}
else if (CCTK_EQUALS(ODE_Method,"RK4-RK2"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
CCTK_REAL dt = (*Original_Delta_Time)/cctkGH->cctk_timefac;
switch (substep)
{
case 1:
case 2:
dt *= 0.5;
break;
default:
dt = 0;
}
cctkGH->cctk_time = (*Original_Time) - dt;
}
#ifdef MOLDEBUG
printf("MoL has once more reset t (%d): %f.\n",
*MoL_Intermediate_Step, cctkGH->cctk_time);
fflush(stdout);
#endif
free(previous_times);
previous_times = NULL;
if (adaptive_stepsize && ! CCTK_EQUALS(verbose, "none"))
{
CCTK_VInfo (CCTK_THORNSTRING, "Evaluating RHS at %g",
(double)cctkGH->cctk_time);
}
}
/*@@
@routine MoL_ResetDeltaTime
@date Mon May 20 09:49:41 2002
@author Ian Hawke
@desc
Sets the timestep during the MoL evolution loop.
At the last time all methods should end up with the original
values for time and timestep.
@enddesc
@calls
@calledby
@history
@endhistory
@@*/
void MoL_ResetDeltaTime(CCTK_ARGUMENTS)
{
DECLARE_CCTK_ARGUMENTS;
DECLARE_CCTK_PARAMETERS;
if (*MoL_Intermediate_Step == 0)
{
cctkGH->cctk_delta_time = (*Original_Delta_Time);
}
else if (CCTK_EQUALS(ODE_Method,"ICN"))
{
if (*MoL_Intermediate_Step == 1)
{
cctkGH->cctk_delta_time = (*Original_Delta_Time);
}
else
{
cctkGH->cctk_delta_time = 0.5*(*Original_Delta_Time);
}
}
else if (CCTK_EQUALS(ODE_Method,"ICN-avg"))
{
cctkGH->cctk_delta_time = (*Original_Delta_Time);
}
else if (CCTK_EQUALS(ODE_Method,"Generic"))
{
cctkGH->cctk_delta_time = RKBetaCoefficients[MoL_Intermediate_Steps -
(*MoL_Intermediate_Step)] *
(*Original_Delta_Time);
}
else if (CCTK_EQUALS(ODE_Method,"RK2"))
{
if (*MoL_Intermediate_Step == 1)
{
cctkGH->cctk_delta_time = 0.5*(*Original_Delta_Time);
}
}
else if (CCTK_EQUALS(ODE_Method,"RK3"))
{
if (*MoL_Intermediate_Step == 2)
{
cctkGH->cctk_delta_time = 0.25*(*Original_Delta_Time);
}
else if (*MoL_Intermediate_Step == 1)
{
cctkGH->cctk_delta_time = 2.0/3.0*(*Original_Delta_Time);
}
}
else if (CCTK_EQUALS(ODE_Method,"RK45") || CCTK_EQUALS(ODE_Method,"RK45CK"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
const CCTK_REAL * alpha_array;
if (CCTK_EQUALS(ODE_Method, "RK45"))
{
alpha_array = alpha_array_F;
}
else if (CCTK_EQUALS(ODE_Method, "RK45CK"))
{
alpha_array = alpha_array_CK;
}
else
{
CCTK_WARN (0, "internal error");
/* Avoid compiler warning */
alpha_array = NULL;
}
cctkGH->cctk_delta_time
= ((alpha_array[substep + 1] - alpha_array[substep])
* (* Original_Delta_Time));
}
else if (CCTK_EQUALS(ODE_Method,"RK65"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
cctkGH->cctk_delta_time
= ((alpha_array65[substep + 1] - alpha_array65[substep])
* (* Original_Delta_Time));
}
else if (CCTK_EQUALS(ODE_Method,"RK87"))
{
const int substep = MoL_Intermediate_Steps - (* MoL_Intermediate_Step);
cctkGH->cctk_delta_time
= ((alpha_array87[substep + 1] - alpha_array87[substep])
* (* Original_Delta_Time));
}
#ifdef MOLDEBUG
printf("MoL has once more reset dt (%d): %f.\n",
*MoL_Intermediate_Step,
cctkGH->cctk_delta_time/cctkGH->cctk_timefac);
fflush(stdout);
#endif
if (adaptive_stepsize && ! CCTK_EQUALS(verbose, "none"))
{
CCTK_VInfo (CCTK_THORNSTRING, "Evaluating RHS with a time step of %g",
(double)cctkGH->cctk_delta_time);
}
}
/********************************************************************
********************* Local Routines *************************
********************************************************************/
|
