PetscErrorCode PetscViewerGetSubViewer_String(PetscViewer viewer,MPI_Comm comm,PetscViewer *sviewer)
{
PetscViewer_String *vstr = (PetscViewer_String*)viewer->data;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = PetscViewerStringOpen(PETSC_COMM_SELF,vstr->head,vstr->maxlen-vstr->curlen,sviewer);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
#include <petsc/private/fortranimpl.h>
#include <petscviewer.h>
#if defined(PETSC_HAVE_FORTRAN_CAPS)
#define petscviewerstringopen_ PETSCVIEWERSTRINGOPEN
#elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
#define petscviewerstringopen_ petscviewerstringopen
#endif
PETSC_EXTERN void PETSC_STDCALL petscviewerstringopen_(MPI_Comm *comm,CHAR name PETSC_MIXED_LEN(len1),PetscInt *len,PetscViewer *str,
PetscErrorCode *ierr PETSC_END_LEN(len1))
{
*ierr = PetscViewerStringOpen(MPI_Comm_f2c(*(MPI_Fint*)&*comm),name,*len,str);
}
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;
}
