PetscErrorCode StokesSetupPC(Stokes* s, KSP ksp) {
KSP* subksp;
PC pc;
PetscInt n = 1;
PetscErrorCode ierr;
PetscFunctionBeginUser;
ierr = KSPGetPC(ksp, &pc);
CHKERRQ(ierr);
ierr = PCFieldSplitSetIS(pc, "0", s->isg[0]);
CHKERRQ(ierr);
ierr = PCFieldSplitSetIS(pc, "1", s->isg[1]);
CHKERRQ(ierr);
if (s->userPC) {
ierr = PCFieldSplitSetSchurPre(pc, PC_FIELDSPLIT_SCHUR_PRE_USER, s->myS);
CHKERRQ(ierr);
}
if (s->userKSP) {
ierr = PCSetUp(pc);
CHKERRQ(ierr);
ierr = PCFieldSplitGetSubKSP(pc, &n, &subksp);
CHKERRQ(ierr);
ierr = KSPSetOperators(subksp[1], s->myS, s->myS);
CHKERRQ(ierr);
ierr = PetscFree(subksp);
CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
PETSC_EXTERN void PETSC_STDCALL pcfieldsplitgetsubksp_(PC *pc,PetscInt *n_local,KSP *ksp,PetscErrorCode *ierr)
{
KSP *tksp;
PetscInt i,nloc;
CHKFORTRANNULLINTEGER(n_local);
*ierr = PCFieldSplitGetSubKSP(*pc,&nloc,&tksp); if (*ierr) return;
if (n_local) *n_local = nloc;
CHKFORTRANNULLOBJECT(ksp);
if (ksp) {
for (i=0; i<nloc; i++) ksp[i] = tksp[i];
}
*ierr = PetscFree(tksp);
}
void setCompositePC(Type* A, PC pc) {
PetscInt nsplits;
KSP* subksp;
PCFieldSplitGetSubKSP(pc, &nsplits, &subksp);
if(A->_S.size() == 1)
KSPSetOperators(subksp[nsplits - 1], A->_S[0], A->_S[0]);
else {
PC pcS;
KSPGetPC(subksp[nsplits - 1], &pcS);
for(int i = 0; i < A->_S.size(); ++i)
PCCompositeAddPC(pcS, PCNONE);
PCSetUp(pcS);
for(int i = 0; i < A->_S.size(); ++i) {
PC subpc;
PCCompositeGetPC(pcS, i, &subpc);
PCSetOperators(subpc, A->_S[i], A->_S[i]);
PCSetFromOptions(subpc);
}
}
PetscFree(subksp);
}
PetscErrorCode SNESSolve_VINEWTONRSLS(SNES snes)
{
SNES_VINEWTONRSLS *vi = (SNES_VINEWTONRSLS*)snes->data;
PetscErrorCode ierr;
PetscInt maxits,i,lits;
PetscBool lssucceed;
MatStructure flg = DIFFERENT_NONZERO_PATTERN;
PetscReal fnorm,gnorm,xnorm=0,ynorm;
Vec Y,X,F;
KSPConvergedReason kspreason;
PetscFunctionBegin;
snes->numFailures = 0;
snes->numLinearSolveFailures = 0;
snes->reason = SNES_CONVERGED_ITERATING;
maxits = snes->max_its; /* maximum number of iterations */
X = snes->vec_sol; /* solution vector */
F = snes->vec_func; /* residual vector */
Y = snes->work[0]; /* work vectors */
ierr = SNESLineSearchSetVIFunctions(snes->linesearch, SNESVIProjectOntoBounds, SNESVIComputeInactiveSetFnorm);CHKERRQ(ierr);
ierr = SNESLineSearchSetVecs(snes->linesearch, X, PETSC_NULL, PETSC_NULL, PETSC_NULL, PETSC_NULL);CHKERRQ(ierr);
ierr = SNESLineSearchSetUp(snes->linesearch);CHKERRQ(ierr);
ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
snes->iter = 0;
snes->norm = 0.0;
ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr);
ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
if (snes->domainerror) {
snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
PetscFunctionReturn(0);
}
ierr = SNESVIComputeInactiveSetFnorm(snes,F,X,&fnorm);CHKERRQ(ierr);
ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr); /* xnorm <- ||x|| */
ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr);
if (PetscIsInfOrNanReal(fnorm)) SETERRQ(((PetscObject)X)->comm,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number");
ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
snes->norm = fnorm;
ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
SNESLogConvHistory(snes,fnorm,0);
ierr = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr);
/* set parameter for default relative tolerance convergence test */
snes->ttol = fnorm*snes->rtol;
/* test convergence */
ierr = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
if (snes->reason) PetscFunctionReturn(0);
for (i=0; i<maxits; i++) {
IS IS_act,IS_inact; /* _act -> active set _inact -> inactive set */
IS IS_redact; /* redundant active set */
VecScatter scat_act,scat_inact;
PetscInt nis_act,nis_inact;
Vec Y_act,Y_inact,F_inact;
Mat jac_inact_inact,prejac_inact_inact;
PetscBool isequal;
/* Call general purpose update function */
if (snes->ops->update) {
ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
}
ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr);
/* Create active and inactive index sets */
/*original
ierr = SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&IS_inact);CHKERRQ(ierr);
*/
ierr = SNESVIGetActiveSetIS(snes,X,F,&IS_act);CHKERRQ(ierr);
if (vi->checkredundancy) {
(*vi->checkredundancy)(snes,IS_act,&IS_redact,vi->ctxP);CHKERRQ(ierr);
if (IS_redact){
ierr = ISSort(IS_redact);CHKERRQ(ierr);
ierr = ISComplement(IS_redact,X->map->rstart,X->map->rend,&IS_inact);CHKERRQ(ierr);
ierr = ISDestroy(&IS_redact);CHKERRQ(ierr);
}
else {
ierr = ISComplement(IS_act,X->map->rstart,X->map->rend,&IS_inact);CHKERRQ(ierr);
}
} else {
ierr = ISComplement(IS_act,X->map->rstart,X->map->rend,&IS_inact);CHKERRQ(ierr);
}
/* Create inactive set submatrix */
ierr = MatGetSubMatrix(snes->jacobian,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);CHKERRQ(ierr);
if (0) { /* Dead code (temporary developer hack) */
IS keptrows;
ierr = MatFindNonzeroRows(jac_inact_inact,&keptrows);CHKERRQ(ierr);
if (keptrows) {
PetscInt cnt,*nrows,k;
const PetscInt *krows,*inact;
PetscInt rstart=jac_inact_inact->rmap->rstart;
ierr = MatDestroy(&jac_inact_inact);CHKERRQ(ierr);
ierr = ISDestroy(&IS_act);CHKERRQ(ierr);
ierr = ISGetLocalSize(keptrows,&cnt);CHKERRQ(ierr);
ierr = ISGetIndices(keptrows,&krows);CHKERRQ(ierr);
ierr = ISGetIndices(IS_inact,&inact);CHKERRQ(ierr);
ierr = PetscMalloc(cnt*sizeof(PetscInt),&nrows);CHKERRQ(ierr);
for (k=0; k<cnt; k++) {
nrows[k] = inact[krows[k]-rstart];
}
ierr = ISRestoreIndices(keptrows,&krows);CHKERRQ(ierr);
ierr = ISRestoreIndices(IS_inact,&inact);CHKERRQ(ierr);
ierr = ISDestroy(&keptrows);CHKERRQ(ierr);
ierr = ISDestroy(&IS_inact);CHKERRQ(ierr);
ierr = ISCreateGeneral(((PetscObject)snes)->comm,cnt,nrows,PETSC_OWN_POINTER,&IS_inact);CHKERRQ(ierr);
ierr = ISComplement(IS_inact,F->map->rstart,F->map->rend,&IS_act);CHKERRQ(ierr);
ierr = MatGetSubMatrix(snes->jacobian,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);CHKERRQ(ierr);
}
}
ierr = DMSetVI(snes->dm,IS_inact);CHKERRQ(ierr);
/* remove later */
/*
ierr = VecView(vi->xu,PETSC_VIEWER_BINARY_(((PetscObject)(vi->xu))->comm));CHKERRQ(ierr);
ierr = VecView(vi->xl,PETSC_VIEWER_BINARY_(((PetscObject)(vi->xl))->comm));CHKERRQ(ierr);
ierr = VecView(X,PETSC_VIEWER_BINARY_(((PetscObject)X)->comm));CHKERRQ(ierr);
ierr = VecView(F,PETSC_VIEWER_BINARY_(((PetscObject)F)->comm));CHKERRQ(ierr);
ierr = ISView(IS_inact,PETSC_VIEWER_BINARY_(((PetscObject)IS_inact)->comm));CHKERRQ(ierr);
*/
/* Get sizes of active and inactive sets */
ierr = ISGetLocalSize(IS_act,&nis_act);CHKERRQ(ierr);
ierr = ISGetLocalSize(IS_inact,&nis_inact);CHKERRQ(ierr);
/* Create active and inactive set vectors */
ierr = SNESCreateSubVectors_VINEWTONRSLS(snes,nis_inact,&F_inact);CHKERRQ(ierr);
ierr = SNESCreateSubVectors_VINEWTONRSLS(snes,nis_act,&Y_act);CHKERRQ(ierr);
ierr = SNESCreateSubVectors_VINEWTONRSLS(snes,nis_inact,&Y_inact);CHKERRQ(ierr);
/* Create scatter contexts */
ierr = VecScatterCreate(Y,IS_act,Y_act,PETSC_NULL,&scat_act);CHKERRQ(ierr);
ierr = VecScatterCreate(Y,IS_inact,Y_inact,PETSC_NULL,&scat_inact);CHKERRQ(ierr);
/* Do a vec scatter to active and inactive set vectors */
ierr = VecScatterBegin(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterBegin(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterBegin(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
/* Active set direction = 0 */
ierr = VecSet(Y_act,0);CHKERRQ(ierr);
if (snes->jacobian != snes->jacobian_pre) {
ierr = MatGetSubMatrix(snes->jacobian_pre,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&prejac_inact_inact);CHKERRQ(ierr);
} else prejac_inact_inact = jac_inact_inact;
ierr = ISEqual(vi->IS_inact_prev,IS_inact,&isequal);CHKERRQ(ierr);
if (!isequal) {
ierr = SNESVIResetPCandKSP(snes,jac_inact_inact,prejac_inact_inact);CHKERRQ(ierr);
flg = DIFFERENT_NONZERO_PATTERN;
}
/* ierr = ISView(IS_inact,0);CHKERRQ(ierr); */
/* ierr = ISView(IS_act,0);CHKERRQ(ierr);*/
/* ierr = MatView(snes->jacobian_pre,0); */
ierr = KSPSetOperators(snes->ksp,jac_inact_inact,prejac_inact_inact,flg);CHKERRQ(ierr);
ierr = KSPSetUp(snes->ksp);CHKERRQ(ierr);
{
PC pc;
PetscBool flg;
ierr = KSPGetPC(snes->ksp,&pc);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject)pc,PCFIELDSPLIT,&flg);CHKERRQ(ierr);
if (flg) {
KSP *subksps;
ierr = PCFieldSplitGetSubKSP(pc,PETSC_NULL,&subksps);CHKERRQ(ierr);
ierr = KSPGetPC(subksps[0],&pc);CHKERRQ(ierr);
ierr = PetscFree(subksps);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject)pc,PCBJACOBI,&flg);CHKERRQ(ierr);
if (flg) {
PetscInt n,N = 101*101,j,cnts[3] = {0,0,0};
const PetscInt *ii;
ierr = ISGetSize(IS_inact,&n);CHKERRQ(ierr);
ierr = ISGetIndices(IS_inact,&ii);CHKERRQ(ierr);
for (j=0; j<n; j++) {
if (ii[j] < N) cnts[0]++;
else if (ii[j] < 2*N) cnts[1]++;
else if (ii[j] < 3*N) cnts[2]++;
}
ierr = ISRestoreIndices(IS_inact,&ii);CHKERRQ(ierr);
ierr = PCBJacobiSetTotalBlocks(pc,3,cnts);CHKERRQ(ierr);
}
}
}
ierr = SNES_KSPSolve(snes,snes->ksp,F_inact,Y_inact);CHKERRQ(ierr);
ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr);
if (kspreason < 0) {
if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) {
ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr);
snes->reason = SNES_DIVERGED_LINEAR_SOLVE;
break;
}
}
ierr = VecScatterBegin(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecScatterEnd(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecScatterBegin(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecScatterEnd(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecDestroy(&F_inact);CHKERRQ(ierr);
ierr = VecDestroy(&Y_act);CHKERRQ(ierr);
ierr = VecDestroy(&Y_inact);CHKERRQ(ierr);
ierr = VecScatterDestroy(&scat_act);CHKERRQ(ierr);
ierr = VecScatterDestroy(&scat_inact);CHKERRQ(ierr);
ierr = ISDestroy(&IS_act);CHKERRQ(ierr);
if (!isequal) {
ierr = ISDestroy(&vi->IS_inact_prev);CHKERRQ(ierr);
ierr = ISDuplicate(IS_inact,&vi->IS_inact_prev);CHKERRQ(ierr);
}
ierr = ISDestroy(&IS_inact);CHKERRQ(ierr);
ierr = MatDestroy(&jac_inact_inact);CHKERRQ(ierr);
if (snes->jacobian != snes->jacobian_pre) {
ierr = MatDestroy(&prejac_inact_inact);CHKERRQ(ierr);
}
ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr);
snes->linear_its += lits;
ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr);
/*
if (snes->ops->precheck) {
PetscBool changed_y = PETSC_FALSE;
ierr = (*snes->ops->precheck)(snes,X,Y,snes->precheck,&changed_y);CHKERRQ(ierr);
}
if (PetscLogPrintInfo){
ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr);
}
*/
/* Compute a (scaled) negative update in the line search routine:
Y <- X - lambda*Y
and evaluate G = function(Y) (depends on the line search).
*/
ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr);
ynorm = 1; gnorm = fnorm;
ierr = SNESLineSearchApply(snes->linesearch, X, F, &gnorm, Y);CHKERRQ(ierr);
ierr = SNESLineSearchGetNorms(snes->linesearch, &xnorm, &gnorm, &ynorm);CHKERRQ(ierr);
ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",(double)fnorm,(double)gnorm,(double)ynorm,(int)lssucceed);CHKERRQ(ierr);
if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break;
if (snes->domainerror) {
snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
ierr = DMDestroyVI(snes->dm);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
ierr = SNESLineSearchGetSuccess(snes->linesearch, &lssucceed);CHKERRQ(ierr);
if (!lssucceed) {
if (++snes->numFailures >= snes->maxFailures) {
PetscBool ismin;
snes->reason = SNES_DIVERGED_LINE_SEARCH;
ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,F,X,gnorm,&ismin);CHKERRQ(ierr);
if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
break;
}
}
/* Update function and solution vectors */
fnorm = gnorm;
/* Monitor convergence */
ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
snes->iter = i+1;
snes->norm = fnorm;
ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
SNESLogConvHistory(snes,snes->norm,lits);
ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);
/* Test for convergence, xnorm = || X || */
if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); }
ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
if (snes->reason) break;
}
ierr = DMDestroyVI(snes->dm);CHKERRQ(ierr);
if (i == maxits) {
ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr);
if (!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT;
}
PetscFunctionReturn(0);
}
PetscErrorCode FluidFieldSetup( FluidField f )
{
PetscLogDouble t1,t2;
PetscErrorCode ierr;
PetscFunctionBegin;
// Assemble viscous matricies
ierr = FluidFieldMatAssemble( f ); CHKERRQ(ierr);
ierr = PetscInfo3( 0, "Lengths: %e %e %e\n", f->lens.x, f->lens.y, f->lens.z ); CHKERRQ(ierr);
ierr = PetscInfo3( 0, "Size: %d %d %d\n", f->dims.x, f->dims.y, f->dims.z ); CHKERRQ(ierr);
ierr = PetscInfo3( 0, "dx: %e %e %e\n", f->dh.x, f->dh.y, f->dh.z ); CHKERRQ(ierr);
ierr = PetscTime(&t1); CHKERRQ(ierr);
// Create vectors
ierr = GACreate( f->daV, &f->ga); CHKERRQ(ierr);
ierr = DMCreateGlobalVector(f->daV,&f->rhs); CHKERRQ(ierr);
ierr = VecDuplicate(f->rhs,&f->vel); CHKERRQ(ierr);
ierr = VecDuplicate(f->rhs,&f->vel0); CHKERRQ(ierr);
// ierr = DACreateGlobalVector(f->daE,&f->E); CHKERRQ(ierr);
ierr = DMCreateGlobalVector(f->daB,&f->buf); CHKERRQ(ierr);
// Set up the outer solver
ierr = KSPCreate(f->comm,&f->ksp); CHKERRQ(ierr);
ierr = KSPSetOperators(f->ksp,f->mat,f->mat, SAME_PRECONDITIONER); CHKERRQ(ierr);
ierr = KSPSetType(f->ksp,KSPFGMRES); CHKERRQ(ierr);
ierr = KSPSetInitialGuessNonzero(f->ksp,PETSC_TRUE); CHKERRQ(ierr);
ierr = KSPSetTolerances(f->ksp,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT); CHKERRQ(ierr);
ierr = KSPSetFromOptions(f->ksp);CHKERRQ(ierr);
// Split pressure from velocity [ u v w | p ]
PC pc;
ierr = KSPGetPC(f->ksp,&pc); CHKERRQ(ierr);
ierr = PCSetType(pc, PCFIELDSPLIT); CHKERRQ(ierr);
ierr = PCFieldSplitSetType(pc,PC_COMPOSITE_SCHUR); CHKERRQ(ierr);
if( f->is3D ) {
const PetscInt ufields[] = {U_FACE,V_FACE,W_FACE};
const PetscInt pfields[] = {CELL_CENTER};
ierr = PCFieldSplitSetBlockSize(pc,4); CHKERRQ(ierr); // [p u v w]
ierr = PCFieldSplitSetFields(pc,"v",3,ufields,ufields); CHKERRQ(ierr); // [u v w]
ierr = PCFieldSplitSetFields(pc,"p",1,pfields,pfields); CHKERRQ(ierr); // [ p ]
} else {
const PetscInt ufields[] = {U_FACE,V_FACE};
const PetscInt pfields[] = {CELL_CENTER};
ierr = PCFieldSplitSetBlockSize(pc,3); CHKERRQ(ierr); // [p u v]
ierr = PCFieldSplitSetFields(pc,"v",2,ufields,ufields); CHKERRQ(ierr); // [u v]
ierr = PCFieldSplitSetFields(pc,"p",1,pfields,pfields); CHKERRQ(ierr); // [ p ]
}
ierr = PCSetUp(pc); CHKERRQ(ierr);
int nVelP;
KSP *kspVelP;
ierr = PCFieldSplitGetSubKSP(pc,&nVelP,&kspVelP); CHKERRQ(ierr);
ierr = KSPSetTolerances(kspVelP[1],PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,4); CHKERRQ(ierr);
ierr = KSPSetType(kspVelP[1],KSPGMRES); CHKERRQ(ierr);
ierr = KSPGetPC(kspVelP[1],&pc); CHKERRQ(ierr);
ierr = PCSetType(pc,PCNONE); CHKERRQ(ierr);
ierr = KSPSetFromOptions(kspVelP[1]);CHKERRQ(ierr);
// Split velocity [u v w] into component matricies [u], [v], [w]
ierr = KSPSetType(kspVelP[0],KSPPREONLY); CHKERRQ(ierr);
ierr = KSPGetPC(kspVelP[0],&pc); CHKERRQ(ierr);
ierr = PCSetType(pc, PCFIELDSPLIT); CHKERRQ(ierr);
ierr = PCFieldSplitSetType(pc,PC_COMPOSITE_ADDITIVE); CHKERRQ(ierr);
ierr = PCFieldSplitSetBlockSize(pc,f->is3D?3:2); CHKERRQ(ierr);
ierr = PCSetUp(pc); CHKERRQ(ierr);
/* Set solver for each velocity component
* Split component velocity as parallel blocks along processors
* Use direct solver for each block
* TODO: use MG, w/FFT on coarse grid
*/
ierr = PetscTime(&t2); CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD,"Finished Solver Setup: %f sec\n",t2-t1); CHKERRQ(ierr);
PetscFunctionReturn(0);
}
ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr);
//Split pressure from velocity
PC pc;
ierr = KSPGetPC(ksp,&pc); CHKERRQ(ierr);
ierr = PCSetType(pc, PCFIELDSPLIT); CHKERRQ(ierr);
ierr = PCFieldSplitSetType(pc,PC_COMPOSITE_SCHUR); CHKERRQ(ierr);
ierr = PCFieldSplitSetBlockSize(pc,3); CHKERRQ(ierr);
ierr = PCFieldSplitSetFields(pc,2,(int[]){0,1}); CHKERRQ(ierr);
ierr = PCFieldSplitSetFields(pc,1,(int[]){2}); CHKERRQ(ierr);
ierr = PCSetUp(pc); CHKERRQ(ierr);
//Split velocity into u-v component matricies
int nVelP;
KSP *kspVelP;
ierr = PCFieldSplitGetSubKSP(pc,&nVelP,&kspVelP); CHKERRQ(ierr);
ierr = KSPSetTolerances(kspVelP[1],1e-50,1e-3,PETSC_DEFAULT,PETSC_DEFAULT); CHKERRQ(ierr);
// ierr = KSPSetType(kspVelP[1],KSPCG); CHKERRQ(ierr);
ierr = KSPGetPC(kspVelP[1],&pc); CHKERRQ(ierr);
ierr = PCSetType(pc,PCNONE); CHKERRQ(ierr);
ierr = KSPSetType(kspVelP[0],KSPPREONLY); CHKERRQ(ierr);
ierr = KSPGetPC(kspVelP[0],&pc); CHKERRQ(ierr);
ierr = PCSetType(pc, PCFIELDSPLIT); CHKERRQ(ierr);
ierr = PCFieldSplitSetType(pc,PC_COMPOSITE_ADDITIVE); CHKERRQ(ierr);
ierr = PCFieldSplitSetBlockSize(pc,2); CHKERRQ(ierr);
ierr = PCSetUp(pc); CHKERRQ(ierr);
//Set solver for each velocity component
int nVel;
KSP *kspVel;
ierr = PCFieldSplitGetSubKSP(pc,&nVel,&kspVel); CHKERRQ(ierr);
