PetscErrorCode RunTest(int nx, int ny, int nz, int loops, double *wt)
{
Vec x,f;
TS ts;
AppCtx _app,*app=&_app;
double t1,t2;
PetscErrorCode ierr;
PetscFunctionBegin;
app->nx = nx; app->h[0] = 1./(nx-1);
app->ny = ny; app->h[1] = 1./(ny-1);
app->nz = nz; app->h[2] = 1./(nz-1);
ierr = VecCreate(PETSC_COMM_SELF,&x);CHKERRQ(ierr);
ierr = VecSetSizes(x,nx*ny*nz,nx*ny*nz);CHKERRQ(ierr);
ierr = VecSetUp(x);CHKERRQ(ierr);
ierr = VecDuplicate(x,&f);CHKERRQ(ierr);
ierr = TSCreate(PETSC_COMM_SELF,&ts);CHKERRQ(ierr);
ierr = TSSetProblemType(ts,TS_NONLINEAR);CHKERRQ(ierr);
ierr = TSSetType(ts,TSTHETA);CHKERRQ(ierr);
ierr = TSThetaSetTheta(ts,1.0);CHKERRQ(ierr);
ierr = TSSetTimeStep(ts,0.01);CHKERRQ(ierr);
ierr = TSSetTime(ts,0.0);CHKERRQ(ierr);
ierr = TSSetDuration(ts,10,1.0);CHKERRQ(ierr);
ierr = TSSetSolution(ts,x);CHKERRQ(ierr);
ierr = TSSetIFunction(ts,f,FormFunction,app);CHKERRQ(ierr);
ierr = PetscOptionsSetValue("-snes_mf","1");CHKERRQ(ierr);
{
SNES snes;
KSP ksp;
ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
ierr = SNESGetKSP(snes,&ksp);CHKERRQ(ierr);
ierr = KSPSetType(ksp,KSPCG);CHKERRQ(ierr);
}
ierr = TSSetFromOptions(ts);CHKERRQ(ierr);
ierr = TSSetUp(ts);CHKERRQ(ierr);
*wt = 1e300;
while (loops-- > 0) {
ierr = FormInitial(0.0,x,app);CHKERRQ(ierr);
ierr = PetscGetTime(&t1);CHKERRQ(ierr);
ierr = TSSolve(ts,x,PETSC_NULL);CHKERRQ(ierr);
ierr = PetscGetTime(&t2);CHKERRQ(ierr);
*wt = PetscMin(*wt,t2-t1);
}
ierr = VecDestroy(&x);CHKERRQ(ierr);
ierr = VecDestroy(&f);CHKERRQ(ierr);
ierr = TSDestroy(&ts);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PetscErrorCode DMTSCheckFromOptions(TS ts, Vec u, PetscErrorCode (**exactFuncs)(PetscInt dim, PetscReal time, const PetscReal x[], PetscInt Nf, PetscScalar *u, void *ctx), void **ctxs)
{
DM dm;
SNES snes;
Vec sol;
PetscBool check;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = PetscOptionsHasName(((PetscObject)ts)->options,((PetscObject)ts)->prefix, "-dmts_check", &check);CHKERRQ(ierr);
if (!check) PetscFunctionReturn(0);
ierr = VecDuplicate(u, &sol);CHKERRQ(ierr);
ierr = TSSetSolution(ts, sol);CHKERRQ(ierr);
ierr = TSGetDM(ts, &dm);CHKERRQ(ierr);
ierr = TSSetUp(ts);CHKERRQ(ierr);
ierr = TSGetSNES(ts, &snes);CHKERRQ(ierr);
ierr = SNESSetSolution(snes, sol);CHKERRQ(ierr);
ierr = DMSNESCheckFromOptions_Internal(snes, dm, u, sol, exactFuncs, ctxs);CHKERRQ(ierr);
ierr = VecDestroy(&sol);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
int main(int argc,char **argv)
{
TS ts; /* timestepping context */
PetscErrorCode ierr;
PetscViewer viewer;
ierr = PetscInitialize(&argc,&argv,NULL,help);if (ierr) return ierr;
ierr = PetscDLLibraryAppend(PETSC_COMM_WORLD,&PetscDLLibrariesLoaded,"advection-diffusion-reaction/ex1");CHKERRQ(ierr);
ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr);
ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,"advection-diffusion-reaction/binaryoutput",FILE_MODE_READ,&viewer);CHKERRQ(ierr);
ierr = TSLoad(ts,viewer);CHKERRQ(ierr);
ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
/* ierr = PetscFPTView(0);CHKERRQ(ierr); */
ierr = TSSetFromOptions(ts);CHKERRQ(ierr);
ierr = TSSetUp(ts);CHKERRQ(ierr);
ierr = TSView(ts,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
ierr = TSSolve(ts,NULL);CHKERRQ(ierr);
ierr = TSDestroy(&ts);CHKERRQ(ierr);
ierr = PetscFinalize();
return ierr;
}
int main(int argc,char **argv)
{
PetscErrorCode ierr;
PetscInt time_steps=100,iout,NOUT=1;
PetscMPIInt size;
Vec global;
PetscReal dt,ftime,ftime_original;
TS ts;
PetscViewer viewfile;
Mat J = 0;
Vec x;
Data data;
PetscInt mn;
PetscBool flg;
MatColoring mc;
ISColoring iscoloring;
MatFDColoring matfdcoloring = 0;
PetscBool fd_jacobian_coloring = PETSC_FALSE;
SNES snes;
KSP ksp;
PC pc;
PetscViewer viewer;
char pcinfo[120],tsinfo[120];
TSType tstype;
PetscBool sundials;
ierr = PetscInitialize(&argc,&argv,(char*)0,help);CHKERRQ(ierr);
ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
/* set data */
data.m = 9;
data.n = 9;
data.a = 1.0;
data.epsilon = 0.1;
data.dx = 1.0/(data.m+1.0);
data.dy = 1.0/(data.n+1.0);
mn = (data.m)*(data.n);
ierr = PetscOptionsGetInt(NULL,"-time",&time_steps,NULL);CHKERRQ(ierr);
/* set initial conditions */
ierr = VecCreate(PETSC_COMM_WORLD,&global);CHKERRQ(ierr);
ierr = VecSetSizes(global,PETSC_DECIDE,mn);CHKERRQ(ierr);
ierr = VecSetFromOptions(global);CHKERRQ(ierr);
ierr = Initial(global,&data);CHKERRQ(ierr);
ierr = VecDuplicate(global,&x);CHKERRQ(ierr);
/* create timestep context */
ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr);
ierr = TSMonitorSet(ts,Monitor,&data,NULL);CHKERRQ(ierr);
#if defined(PETSC_HAVE_SUNDIALS)
ierr = TSSetType(ts,TSSUNDIALS);CHKERRQ(ierr);
#else
ierr = TSSetType(ts,TSEULER);CHKERRQ(ierr);
#endif
dt = 0.1;
ftime_original = data.tfinal = 1.0;
ierr = TSSetInitialTimeStep(ts,0.0,dt);CHKERRQ(ierr);
ierr = TSSetDuration(ts,time_steps,ftime_original);CHKERRQ(ierr);
ierr = TSSetSolution(ts,global);CHKERRQ(ierr);
/* set user provided RHSFunction and RHSJacobian */
ierr = TSSetRHSFunction(ts,NULL,RHSFunction,&data);CHKERRQ(ierr);
ierr = MatCreate(PETSC_COMM_WORLD,&J);CHKERRQ(ierr);
ierr = MatSetSizes(J,PETSC_DECIDE,PETSC_DECIDE,mn,mn);CHKERRQ(ierr);
ierr = MatSetFromOptions(J);CHKERRQ(ierr);
ierr = MatSeqAIJSetPreallocation(J,5,NULL);CHKERRQ(ierr);
ierr = MatMPIAIJSetPreallocation(J,5,NULL,5,NULL);CHKERRQ(ierr);
ierr = PetscOptionsHasName(NULL,"-ts_fd",&flg);CHKERRQ(ierr);
if (!flg) {
ierr = TSSetRHSJacobian(ts,J,J,RHSJacobian,&data);CHKERRQ(ierr);
} else {
ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
ierr = PetscOptionsHasName(NULL,"-fd_color",&fd_jacobian_coloring);CHKERRQ(ierr);
if (fd_jacobian_coloring) { /* Use finite differences with coloring */
/* Get data structure of J */
PetscBool pc_diagonal;
ierr = PetscOptionsHasName(NULL,"-pc_diagonal",&pc_diagonal);CHKERRQ(ierr);
if (pc_diagonal) { /* the preconditioner of J is a diagonal matrix */
PetscInt rstart,rend,i;
PetscScalar zero=0.0;
ierr = MatGetOwnershipRange(J,&rstart,&rend);CHKERRQ(ierr);
for (i=rstart; i<rend; i++) {
ierr = MatSetValues(J,1,&i,1,&i,&zero,INSERT_VALUES);CHKERRQ(ierr);
}
ierr = MatAssemblyBegin(J,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(J,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
} else {
/* Fill the structure using the expensive SNESComputeJacobianDefault. Temporarily set up the TS so we can call this function */
ierr = TSSetType(ts,TSBEULER);CHKERRQ(ierr);
ierr = TSSetUp(ts);CHKERRQ(ierr);
ierr = SNESComputeJacobianDefault(snes,x,J,J,ts);CHKERRQ(ierr);
}
/* create coloring context */
ierr = MatColoringCreate(J,&mc);CHKERRQ(ierr);
ierr = MatColoringSetType(mc,MATCOLORINGSL);CHKERRQ(ierr);
ierr = MatColoringSetFromOptions(mc);CHKERRQ(ierr);
ierr = MatColoringApply(mc,&iscoloring);CHKERRQ(ierr);
ierr = MatColoringDestroy(&mc);CHKERRQ(ierr);
ierr = MatFDColoringCreate(J,iscoloring,&matfdcoloring);CHKERRQ(ierr);
ierr = MatFDColoringSetFunction(matfdcoloring,(PetscErrorCode (*)(void))SNESTSFormFunction,ts);CHKERRQ(ierr);
ierr = MatFDColoringSetFromOptions(matfdcoloring);CHKERRQ(ierr);
ierr = MatFDColoringSetUp(J,iscoloring,matfdcoloring);CHKERRQ(ierr);
ierr = SNESSetJacobian(snes,J,J,SNESComputeJacobianDefaultColor,matfdcoloring);CHKERRQ(ierr);
ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
} else { /* Use finite differences (slow) */
ierr = SNESSetJacobian(snes,J,J,SNESComputeJacobianDefault,NULL);CHKERRQ(ierr);
}
}
/* Pick up a Petsc preconditioner */
/* one can always set method or preconditioner during the run time */
ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
ierr = SNESGetKSP(snes,&ksp);CHKERRQ(ierr);
ierr = KSPGetPC(ksp,&pc);CHKERRQ(ierr);
ierr = PCSetType(pc,PCJACOBI);CHKERRQ(ierr);
ierr = TSSetFromOptions(ts);CHKERRQ(ierr);
ierr = TSSetUp(ts);CHKERRQ(ierr);
/* Test TSSetPostStep() */
ierr = PetscOptionsHasName(NULL,"-test_PostStep",&flg);CHKERRQ(ierr);
if (flg) {
ierr = TSSetPostStep(ts,PostStep);CHKERRQ(ierr);
}
ierr = PetscOptionsGetInt(NULL,"-NOUT",&NOUT,NULL);CHKERRQ(ierr);
for (iout=1; iout<=NOUT; iout++) {
ierr = TSSetDuration(ts,time_steps,iout*ftime_original/NOUT);CHKERRQ(ierr);
ierr = TSSolve(ts,global);CHKERRQ(ierr);
ierr = TSGetSolveTime(ts,&ftime);CHKERRQ(ierr);
ierr = TSSetInitialTimeStep(ts,ftime,dt);CHKERRQ(ierr);
}
/* Interpolate solution at tfinal */
ierr = TSGetSolution(ts,&global);CHKERRQ(ierr);
ierr = TSInterpolate(ts,ftime_original,global);CHKERRQ(ierr);
ierr = PetscOptionsHasName(NULL,"-matlab_view",&flg);CHKERRQ(ierr);
if (flg) { /* print solution into a MATLAB file */
ierr = PetscViewerASCIIOpen(PETSC_COMM_WORLD,"out.m",&viewfile);CHKERRQ(ierr);
ierr = PetscViewerSetFormat(viewfile,PETSC_VIEWER_ASCII_MATLAB);CHKERRQ(ierr);
ierr = VecView(global,viewfile);CHKERRQ(ierr);
ierr = PetscViewerDestroy(&viewfile);CHKERRQ(ierr);
}
/* display solver info for Sundials */
ierr = TSGetType(ts,&tstype);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject)ts,TSSUNDIALS,&sundials);CHKERRQ(ierr);
if (sundials) {
ierr = PetscViewerStringOpen(PETSC_COMM_WORLD,tsinfo,120,&viewer);CHKERRQ(ierr);
ierr = TSView(ts,viewer);CHKERRQ(ierr);
ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
ierr = PetscViewerStringOpen(PETSC_COMM_WORLD,pcinfo,120,&viewer);CHKERRQ(ierr);
ierr = PCView(pc,viewer);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD,"%d Procs,%s TSType, %s Preconditioner\n",size,tsinfo,pcinfo);CHKERRQ(ierr);
ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
}
/* free the memories */
ierr = TSDestroy(&ts);CHKERRQ(ierr);
ierr = VecDestroy(&global);CHKERRQ(ierr);
ierr = VecDestroy(&x);CHKERRQ(ierr);
ierr = MatDestroy(&J);CHKERRQ(ierr);
if (fd_jacobian_coloring) {ierr = MatFDColoringDestroy(&matfdcoloring);CHKERRQ(ierr);}
ierr = PetscFinalize();
return 0;
}
int main(int argc,char **argv)
{
TS ts; /* timestepping context */
Vec x,r; /* solution, residual vectors */
Mat J; /* Jacobian matrix */
AppCtx user; /* user-defined work context */
PetscInt its,N; /* iterations for convergence */
PetscErrorCode ierr;
PetscReal param_max = 6.81,param_min = 0.,dt;
PetscReal ftime;
PetscMPIInt size;
PetscInitialize(&argc,&argv,NULL,help);
ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);
if (size != 1) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP,"This is a uniprocessor example only");
user.mx = 4;
user.my = 4;
user.param = 6.0;
/*
Allow user to set the grid dimensions and nonlinearity parameter at run-time
*/
PetscOptionsGetInt(NULL,"-mx",&user.mx,NULL);
PetscOptionsGetInt(NULL,"-my",&user.my,NULL);
N = user.mx*user.my;
dt = .5/PetscMax(user.mx,user.my);
PetscOptionsGetReal(NULL,"-param",&user.param,NULL);
if (user.param >= param_max || user.param <= param_min) SETERRQ(PETSC_COMM_SELF,1,"Parameter is out of range");
/*
Create vectors to hold the solution and function value
*/
ierr = VecCreateSeq(PETSC_COMM_SELF,N,&x);CHKERRQ(ierr);
ierr = VecDuplicate(x,&r);CHKERRQ(ierr);
/*
Create matrix to hold Jacobian. Preallocate 5 nonzeros per row
in the sparse matrix. Note that this is not the optimal strategy; see
the Performance chapter of the users manual for information on
preallocating memory in sparse matrices.
*/
ierr = MatCreateSeqAIJ(PETSC_COMM_SELF,N,N,5,0,&J);CHKERRQ(ierr);
/*
Create timestepper context
*/
ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr);
ierr = TSSetProblemType(ts,TS_NONLINEAR);CHKERRQ(ierr);
/*
Tell the timestepper context where to compute solutions
*/
ierr = TSSetSolution(ts,x);CHKERRQ(ierr);
/*
Provide the call-back for the nonlinear function we are
evaluating. Thus whenever the timestepping routines need the
function they will call this routine. Note the final argument
is the application context used by the call-back functions.
*/
ierr = TSSetRHSFunction(ts,NULL,FormFunction,&user);CHKERRQ(ierr);
/*
Set the Jacobian matrix and the function used to compute
Jacobians.
*/
ierr = TSSetRHSJacobian(ts,J,J,FormJacobian,&user);CHKERRQ(ierr);
/*
Form the initial guess for the problem
*/
ierr = FormInitialGuess(x,&user);
/*
This indicates that we are using pseudo timestepping to
find a steady state solution to the nonlinear problem.
*/
ierr = TSSetType(ts,TSPSEUDO);CHKERRQ(ierr);
/*
Set the initial time to start at (this is arbitrary for
steady state problems); and the initial timestep given above
*/
ierr = TSSetInitialTimeStep(ts,0.0,dt);CHKERRQ(ierr);
/*
Set a large number of timesteps and final duration time
to insure convergence to steady state.
*/
ierr = TSSetDuration(ts,1000,1.e12);
/*
Use the default strategy for increasing the timestep
*/
ierr = TSPseudoSetTimeStep(ts,TSPseudoTimeStepDefault,0);CHKERRQ(ierr);
/*
Set any additional options from the options database. This
includes all options for the nonlinear and linear solvers used
internally the the timestepping routines.
*/
ierr = TSSetFromOptions(ts);CHKERRQ(ierr);
ierr = TSSetUp(ts);CHKERRQ(ierr);
/*
Perform the solve. This is where the timestepping takes place.
*/
ierr = TSSolve(ts,x);CHKERRQ(ierr);
ierr = TSGetSolveTime(ts,&ftime);CHKERRQ(ierr);
/*
Get the number of steps
*/
ierr = TSGetTimeStepNumber(ts,&its);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD,"Number of pseudo timesteps = %D final time %4.2e\n",its,(double)ftime);CHKERRQ(ierr);
/*
Free the data structures constructed above
*/
ierr = VecDestroy(&x);CHKERRQ(ierr);
ierr = VecDestroy(&r);CHKERRQ(ierr);
ierr = MatDestroy(&J);CHKERRQ(ierr);
ierr = TSDestroy(&ts);CHKERRQ(ierr);
ierr = PetscFinalize();
return 0;
}
void PETSC_STDCALL tssetup_(TS ts, int *__ierr ){
*__ierr = TSSetUp(
(TS)PetscToPointer((ts) ));
}
int main(int argc, char **argv)
{
TS ts; /* time-stepping context */
Vec x; /* State vector */
Mat J; /* Jacobian matrix */
AppCtx user; /* user-defined context */
PetscErrorCode ierr;
PetscReal ftime;
PetscInt its;
PetscMPIInt size;
PetscInitialize(&argc, &argv, NULL, help);
ierr = MPI_Comm_size(PETSC_COMM_WORLD, &size);
if(size != 1) SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_SUP, "This is a uniprocessor example only");
/*
* Allow user to set the grid dimensions and the equations parameters
*/
user.nb_cells = 50;
user.alpha = 10.;
user.beta = 1.;
user.rho_a = 1.;
user.rho_h = 2.;
user.mu_a = 2.;
user.mu_h = 3.;
user.D_a = 0.;
user.D_h = 30.;
ierr = PetscOptionsBegin(PETSC_COMM_WORLD, "", "Problem settings", "PROBLEM");
ierr = PetscOptionsInt("-nb_cells", "Number of cells", "ex42.c",user.nb_cells, &user.nb_cells,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-alpha", "Autocatalysis factor", "ex42.c",user.alpha, &user.alpha,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-beta", "Inhibition factor", "ex42.c",user.beta, &user.beta,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-rho_a", "Default production of the activator", "ex42.c",user.rho_a, &user.rho_a,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-mu_a", "Degradation rate of the activator", "ex42.c",user.mu_a, &user.mu_a,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-D_a", "Diffusion rate of the activator", "ex42.c",user.D_a, &user.D_a,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-rho_h", "Default production of the inhibitor", "ex42.c",user.rho_h, &user.rho_h,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-mu_h", "Degradation rate of the inhibitor", "ex42.c",user.mu_h, &user.mu_h,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-D_h", "Diffusion rate of the inhibitor", "ex42.c",user.D_h, &user.D_h,NULL);CHKERRQ(ierr);
ierr = PetscOptionsEnd();
ierr = PetscPrintf(PETSC_COMM_WORLD, "nb_cells: %D\n", user.nb_cells);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD, "alpha: %5.5g\n", user.alpha);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD, "beta: %5.5g\n", user.beta);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD, "rho_a: %5.5g\n", user.rho_a);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD, "mu_a: %5.5g\n", user.mu_a);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD, "D_a: %5.5g\n", user.D_a);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD, "rho_h: %5.5g\n", user.rho_h);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD, "mu_h: %5.5g\n", user.mu_h);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD, "D_h: %5.5g\n", user.D_h);CHKERRQ(ierr);
/*
* Create vector to hold the solution
*/
ierr = VecCreateSeq(PETSC_COMM_WORLD, 2*user.nb_cells, &x);CHKERRQ(ierr);
/*
* Create time-stepper context
*/
ierr = TSCreate(PETSC_COMM_WORLD, &ts);CHKERRQ(ierr);
ierr = TSSetProblemType(ts, TS_NONLINEAR);CHKERRQ(ierr);
/*
* Tell the time-stepper context where to compute the solution
*/
ierr = TSSetSolution(ts, x);CHKERRQ(ierr);
/*
* Allocate the jacobian matrix
*/
ierr = MatCreateSeqAIJ(PETSC_COMM_WORLD, 2*user.nb_cells, 2*user.nb_cells, 4, 0, &J);CHKERRQ(ierr);
/*
* Provide the call-back for the non-linear function we are evaluating.
*/
ierr = TSSetRHSFunction(ts, NULL, RHSFunction, &user);CHKERRQ(ierr);
/*
* Set the Jacobian matrix and the function user to compute Jacobians
*/
ierr = TSSetRHSJacobian(ts, J, J, RHSJacobian, &user);CHKERRQ(ierr);
/*
* Set the function checking the domain
*/
ierr = TSSetFunctionDomainError(ts, &DomainErrorFunction);CHKERRQ(ierr);
/*
* Initialize the problem with random values
*/
ierr = FormInitialState(x, &user);CHKERRQ(ierr);
/*
* Read the solver type from options
*/
ierr = TSSetType(ts, TSPSEUDO);CHKERRQ(ierr);
/*
* Set a large number of timesteps and final duration time to insure
* convergenge to steady state
*/
ierr = TSSetDuration(ts, 5000, 1e12);
/*
* Set a larger number of potential errors
*/
ierr = TSSetMaxStepRejections(ts, 50);CHKERRQ(ierr);
/*
* Also start with a very small dt
*/
ierr = TSSetTimeStep(ts, 0.05);CHKERRQ(ierr);
/*
* Set a larger time step increment
*/
ierr = TSPseudoSetTimeStepIncrement(ts, 1.5);CHKERRQ(ierr);
/*
* Let the user personalise TS
*/
ierr = TSSetFromOptions(ts);CHKERRQ(ierr);
/*
* Set the context for the time stepper
*/
ierr = TSSetApplicationContext(ts, &user);CHKERRQ(ierr);
/*
* Setup the time stepper, ready for evaluation
*/
ierr = TSSetUp(ts);CHKERRQ(ierr);
/*
* Perform the solve.
*/
ierr = TSSolve(ts, x);CHKERRQ(ierr);
ierr = TSGetSolveTime(ts, &ftime);CHKERRQ(ierr);
ierr = TSGetTimeStepNumber(ts,&its);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD, "Number of time steps = %D, final time: %4.2e\nResult:\n\n", its, (double)ftime);CHKERRQ(ierr);
ierr = PrintSolution(x, &user);CHKERRQ(ierr);
/*
* Free the data structures
*/
ierr = VecDestroy(&x);CHKERRQ(ierr);
ierr = MatDestroy(&J);CHKERRQ(ierr);
ierr = TSDestroy(&ts);CHKERRQ(ierr);
ierr = PetscFinalize();
return 0;
}
