C++ PetscOptionsEnum函数代码示例

PetscErrorCode MatPartitioningSetFromOptions_Chaco(MatPartitioning part)
{
  PetscErrorCode        ierr;
  PetscInt              i;
  PetscReal             r;
  PetscBool             flag;
  MatPartitioning_Chaco *chaco = (MatPartitioning_Chaco*)part->data;
  MPChacoGlobalType     global;
  MPChacoLocalType      local;
  MPChacoEigenType      eigen;

  PetscFunctionBegin;
  ierr = PetscOptionsHead("Chaco partitioning options");CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-mat_partitioning_chaco_global","Global method","MatPartitioningChacoSetGlobal",MPChacoGlobalTypes,(PetscEnum)chaco->global_method,(PetscEnum*)&global,&flag);CHKERRQ(ierr);
  if (flag) { ierr = MatPartitioningChacoSetGlobal(part,global);CHKERRQ(ierr); }
  ierr = PetscOptionsEnum("-mat_partitioning_chaco_local","Local method","MatPartitioningChacoSetLocal",MPChacoLocalTypes,(PetscEnum)chaco->local_method,(PetscEnum*)&local,&flag);CHKERRQ(ierr);
  if (flag) { ierr = MatPartitioningChacoSetLocal(part,local);CHKERRQ(ierr); }
  ierr = PetscOptionsReal("-mat_partitioning_chaco_coarse","Coarse level","MatPartitioningChacoSetCoarseLevel",0.0,&r,&flag);CHKERRQ(ierr);
  if (flag) { ierr = MatPartitioningChacoSetCoarseLevel(part,r);CHKERRQ(ierr); }
  ierr = PetscOptionsEnum("-mat_partitioning_chaco_eigen_solver","Eigensolver method","MatPartitioningChacoSetEigenSolver",MPChacoEigenTypes,(PetscEnum)chaco->eigen_method,(PetscEnum*)&eigen,&flag);CHKERRQ(ierr);
  if (flag) { ierr = MatPartitioningChacoSetEigenSolver(part,eigen);CHKERRQ(ierr); }
  ierr = PetscOptionsReal("-mat_partitioning_chaco_eigen_tol","Eigensolver tolerance","MatPartitioningChacoSetEigenTol",chaco->eigtol,&r,&flag);CHKERRQ(ierr);
  if (flag) { ierr = MatPartitioningChacoSetEigenTol(part,r);CHKERRQ(ierr); }
  ierr = PetscOptionsInt("-mat_partitioning_chaco_eigen_number","Number of eigenvectors: 1, 2, or 3 (bi-, quadri-, or octosection)","MatPartitioningChacoSetEigenNumber",chaco->eignum,&i,&flag);CHKERRQ(ierr);
  if (flag) { ierr = MatPartitioningChacoSetEigenNumber(part,i);CHKERRQ(ierr); }
  ierr = PetscOptionsBool("-mat_partitioning_chaco_verbose","Show library output","",chaco->verbose,&chaco->verbose,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

static PetscErrorCode SNESSetFromOptions_QN(SNES snes)
{

  PetscErrorCode    ierr;
  SNES_QN           *qn    = (SNES_QN*)snes->data;
  PetscBool         monflg = PETSC_FALSE,flg;
  SNESLineSearch    linesearch;
  SNESQNRestartType rtype = qn->restart_type;
  SNESQNScaleType   stype = qn->scale_type;

  PetscFunctionBegin;
  ierr = PetscOptionsHead("SNES QN options");CHKERRQ(ierr);
  ierr = PetscOptionsInt("-snes_qn_m","Number of past states saved for L-BFGS methods","SNESQN",qn->m,&qn->m,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsReal("-snes_qn_powell_gamma","Powell angle tolerance",          "SNESQN", qn->powell_gamma, &qn->powell_gamma, NULL);CHKERRQ(ierr);
  ierr = PetscOptionsReal("-snes_qn_powell_downhill","Powell descent tolerance",        "SNESQN", qn->powell_downhill, &qn->powell_downhill, NULL);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-snes_qn_monitor",         "Monitor for the QN methods",      "SNESQN", monflg, &monflg, NULL);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-snes_qn_single_reduction", "Aggregate reductions",           "SNESQN", qn->singlereduction, &qn->singlereduction, NULL);CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-snes_qn_scale_type","Scaling type","SNESQNSetScaleType",SNESQNScaleTypes,(PetscEnum)stype,(PetscEnum*)&stype,&flg);CHKERRQ(ierr);
  if (flg) ierr = SNESQNSetScaleType(snes,stype);CHKERRQ(ierr);

  ierr = PetscOptionsEnum("-snes_qn_restart_type","Restart type","SNESQNSetRestartType",SNESQNRestartTypes,(PetscEnum)rtype,(PetscEnum*)&rtype,&flg);CHKERRQ(ierr);
  if (flg) ierr = SNESQNSetRestartType(snes,rtype);CHKERRQ(ierr);

  ierr = PetscOptionsEnum("-snes_qn_type","Quasi-Newton update type","",SNESQNTypes,
                          (PetscEnum)qn->type,(PetscEnum*)&qn->type,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  if (!snes->linesearch) {
    ierr = SNESGetLineSearch(snes, &linesearch);CHKERRQ(ierr);
    ierr = SNESLineSearchSetType(linesearch, SNESLINESEARCHCP);CHKERRQ(ierr);
  }
  if (monflg) {
    qn->monitor = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes));CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}

/*
   TSAdaptSetFromOptions - Sets various TSAdapt parameters from user options.

   Collective on TSAdapt

   Input Parameter:
.  adapt - the TSAdapt context

   Options Database Keys:
.  -ts_adapt_type <type> - basic

   Level: advanced

   Notes:
   This function is automatically called by TSSetFromOptions()

.keywords: TS, TSGetAdapt(), TSAdaptSetType()

.seealso: TSGetType()
*/
PetscErrorCode  TSAdaptSetFromOptions(PetscOptionItems *PetscOptionsObject,TSAdapt adapt)
{
  PetscErrorCode ierr;
  char           type[256] = TSADAPTBASIC;
  PetscBool      set,flg;

  PetscFunctionBegin;
  PetscValidHeaderSpecific(adapt,TSADAPT_CLASSID,1);
  /* This should use PetscOptionsBegin() if/when this becomes an object used outside of TS, but currently this
   * function can only be called from inside TSSetFromOptions()  */
  ierr = PetscOptionsHead(PetscOptionsObject,"TS Adaptivity options");CHKERRQ(ierr);
  ierr = PetscOptionsFList("-ts_adapt_type","Algorithm to use for adaptivity","TSAdaptSetType",TSAdaptList,
                          ((PetscObject)adapt)->type_name ? ((PetscObject)adapt)->type_name : type,type,sizeof(type),&flg);CHKERRQ(ierr);
  if (flg || !((PetscObject)adapt)->type_name) {
    ierr = TSAdaptSetType(adapt,type);CHKERRQ(ierr);
  }
  ierr = PetscOptionsReal("-ts_adapt_dt_min","Minimum time step considered","TSAdaptSetStepLimits",adapt->dt_min,&adapt->dt_min,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsReal("-ts_adapt_dt_max","Maximum time step considered","TSAdaptSetStepLimits",adapt->dt_max,&adapt->dt_max,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsReal("-ts_adapt_scale_solve_failed","Scale step by this factor if solve fails","",adapt->scale_solve_failed,&adapt->scale_solve_failed,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-ts_adapt_monitor","Print choices made by adaptive controller","TSAdaptSetMonitor",adapt->monitor ? PETSC_TRUE : PETSC_FALSE,&flg,&set);CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-ts_adapt_wnormtype","Type of norm computed for error estimation","",NormTypes,(PetscEnum)adapt->wnormtype,(PetscEnum*)&adapt->wnormtype,NULL);CHKERRQ(ierr);
  if (adapt->wnormtype != NORM_2 && adapt->wnormtype != NORM_INFINITY) SETERRQ(PetscObjectComm((PetscObject)adapt),PETSC_ERR_SUP,"Only 2-norm and infinite norm supported");
  if (set) {ierr = TSAdaptSetMonitor(adapt,flg);CHKERRQ(ierr);}
  if (adapt->ops->setfromoptions) {ierr = (*adapt->ops->setfromoptions)(PetscOptionsObject,adapt);CHKERRQ(ierr);}
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

static PetscErrorCode PCSetFromOptions_Composite(PC pc)
{
  PC_Composite     *jac = (PC_Composite*)pc->data;
  PetscErrorCode   ierr;
  PetscInt         nmax = 8,i;
  PC_CompositeLink next;
  char             *pcs[8];
  PetscBool        flg;

  PetscFunctionBegin;
  ierr = PetscOptionsHead("Composite preconditioner options");CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-pc_composite_type","Type of composition","PCCompositeSetType",PCCompositeTypes,(PetscEnum)jac->type,(PetscEnum*)&jac->type,&flg);CHKERRQ(ierr);
  if (flg) {
    ierr = PCCompositeSetType(pc,jac->type);CHKERRQ(ierr);
  }
  ierr = PetscOptionsStringArray("-pc_composite_pcs","List of composite solvers","PCCompositeAddPC",pcs,&nmax,&flg);CHKERRQ(ierr);
  if (flg) {
    for (i=0; i<nmax; i++) {
      ierr = PCCompositeAddPC(pc,pcs[i]);CHKERRQ(ierr);
      ierr = PetscFree(pcs[i]);CHKERRQ(ierr);   /* deallocate string pcs[i], which is allocated in PetscOptionsStringArray() */
    }
  }
  ierr = PetscOptionsTail();CHKERRQ(ierr);

  next = jac->head;
  while (next) {
    ierr = PCSetFromOptions(next->pc);CHKERRQ(ierr);
    next = next->next;
  }
  PetscFunctionReturn(0);
}

static PetscErrorCode SNESSetFromOptions_NCG(SNES snes)
{
  SNES_NCG       *ncg = (SNES_NCG*)snes->data;
  PetscErrorCode ierr;
  PetscBool      debug;
  SNESLineSearch linesearch;
  SNESNCGType    ncgtype=ncg->type;

  PetscFunctionBegin;
  ierr = PetscOptionsHead("SNES NCG options");CHKERRQ(ierr);
  ierr = PetscOptionsBool("-snes_ncg_monitor","Monitor NCG iterations","SNES",ncg->monitor ? PETSC_TRUE : PETSC_FALSE, &debug, NULL);CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-snes_ncg_type","NCG Beta type used","SNESNCGSetType",SNESNCGTypes,(PetscEnum)ncg->type,(PetscEnum*)&ncgtype,NULL);CHKERRQ(ierr);
  ierr = SNESNCGSetType(snes, ncgtype);CHKERRQ(ierr);
  if (debug) {
    ncg->monitor = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes));CHKERRQ(ierr);
  }
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  if (!snes->linesearch) {
    ierr = SNESGetLineSearch(snes, &linesearch);CHKERRQ(ierr);
    if (!snes->pc) {
      ierr = SNESLineSearchSetType(linesearch, SNESLINESEARCHCP);CHKERRQ(ierr);
    } else {
      ierr = SNESLineSearchSetType(linesearch, SNESLINESEARCHL2);CHKERRQ(ierr);
    }
  }
  ierr = SNESLineSearchRegister(SNESLINESEARCHNCGLINEAR, SNESLineSearchCreate_NCGLinear);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

PetscErrorCode SNESSetFromOptions_Anderson(PetscOptions *PetscOptionsObject,SNES snes)
{
  SNES_NGMRES    *ngmres = (SNES_NGMRES*) snes->data;
  PetscErrorCode ierr;
  PetscBool      debug;
  SNESLineSearch linesearch;

  PetscFunctionBegin;
  ierr = PetscOptionsHead(PetscOptionsObject,"SNES NGMRES options");CHKERRQ(ierr);
  ierr = PetscOptionsInt("-snes_anderson_m",            "Number of directions","SNES",ngmres->msize,&ngmres->msize,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsReal("-snes_anderson_beta",        "Mixing parameter","SNES",ngmres->andersonBeta,&ngmres->andersonBeta,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-snes_anderson_monitor",     "Monitor steps of Anderson Mixing","SNES",ngmres->monitor ? PETSC_TRUE : PETSC_FALSE,&debug,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsInt("-snes_anderson_restart",      "Iterations before forced restart", "SNES",ngmres->restart_periodic,&ngmres->restart_periodic,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsInt("-snes_anderson_restart_it",   "Tolerance iterations before restart","SNES",ngmres->restart_it,&ngmres->restart_it,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-snes_anderson_restart_type","Restart type","SNESNGMRESSetRestartType",SNESNGMRESRestartTypes,
                          (PetscEnum)ngmres->restart_type,(PetscEnum*)&ngmres->restart_type,NULL);CHKERRQ(ierr);
  if (debug) {
    ngmres->monitor = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes));CHKERRQ(ierr);
  }
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  /* set the default type of the line search if the user hasn't already. */
  if (!snes->linesearch) {
    ierr = SNESGetLineSearch(snes,&linesearch);CHKERRQ(ierr);
    ierr = SNESLineSearchSetType(linesearch,SNESLINESEARCHBASIC);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}

PetscErrorCode PetscSubcommSetFromOptions(PetscSubcomm psubcomm)
{
  PetscErrorCode ierr;
  PetscSubcommType type;
  PetscBool      flg;

  PetscFunctionBegin;
  if (!psubcomm) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"Must call PetscSubcommCreate firt");
  type = psubcomm->type;
  ierr = PetscOptionsEnum("-psubcomm_type","PETSc subcommunicator","PetscSubcommSetType",PetscSubcommTypes,(PetscEnum)type,(PetscEnum*)&type,&flg);CHKERRQ(ierr);
  if (flg && psubcomm->type != type) {
    /* free old structures */
    ierr = PetscCommDestroy(&(psubcomm)->dupparent);CHKERRQ(ierr);
    ierr = PetscCommDestroy(&(psubcomm)->comm);CHKERRQ(ierr);
    ierr = PetscFree((psubcomm)->subsize);CHKERRQ(ierr);
    switch (type) {
    case PETSC_SUBCOMM_GENERAL:
      SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Runtime option PETSC_SUBCOMM_GENERAL is not supported, use PetscSubcommSetTypeGeneral()");
    case PETSC_SUBCOMM_CONTIGUOUS:
      ierr = PetscSubcommCreate_contiguous(psubcomm);CHKERRQ(ierr);
      break;
    case PETSC_SUBCOMM_INTERLACED:
      ierr = PetscSubcommCreate_interlaced(psubcomm);CHKERRQ(ierr);
      break;
    default:
      SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"PetscSubcommType %s is not supported yet",PetscSubcommTypes[type]);
    }
  }

  ierr = PetscOptionsHasName(NULL, "-psubcomm_view", &flg);CHKERRQ(ierr);
  if (flg) {
    ierr = PetscSubcommView(psubcomm,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}

static PetscErrorCode SNESSetFromOptions_Multiblock(SNES snes)
{
  SNES_Multiblock *mb = (SNES_Multiblock *) snes->data;
  PCCompositeType  ctype;
  PetscInt         bs;
  PetscBool        flg;
  PetscErrorCode   ierr;

  PetscFunctionBegin;
  ierr = PetscOptionsHead("SNES Multiblock options");CHKERRQ(ierr);
  ierr = PetscOptionsInt("-snes_multiblock_block_size", "Blocksize that defines number of fields", "PCFieldSplitSetBlockSize", mb->bs, &bs, &flg);CHKERRQ(ierr);
  if (flg) {ierr = SNESMultiblockSetBlockSize(snes, bs);CHKERRQ(ierr);}
  ierr = PetscOptionsEnum("-snes_multiblock_type", "Type of composition", "PCFieldSplitSetType", PCCompositeTypes, (PetscEnum) mb->type, (PetscEnum *) &ctype, &flg);CHKERRQ(ierr);
  if (flg) {
    ierr = SNESMultiblockSetType(snes,ctype);CHKERRQ(ierr);
  }
  /* Only setup fields once */
  if ((mb->bs > 0) && (mb->numBlocks == 0)) {
    /* only allow user to set fields from command line if bs is already known, otherwise user can set them in SNESMultiblockSetDefaults() */
    ierr = SNESMultiblockSetFieldsRuntime_Private(snes);CHKERRQ(ierr);
    if (mb->defined) {ierr = PetscInfo(snes, "Blocks defined using the options database\n");CHKERRQ(ierr);}
  }
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

PetscErrorCode SNESSetFromOptions_NASM(SNES snes)
{
  PetscErrorCode    ierr;
  PCASMType         asmtype;
  PetscBool         flg,monflg,subviewflg;
  SNES_NASM         *nasm = (SNES_NASM*)snes->data;

  PetscFunctionBegin;
  ierr = PetscOptionsHead("Nonlinear Additive Schwartz options");CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-snes_nasm_type","Type of restriction/extension","",SNESNASMTypes,(PetscEnum)nasm->type,(PetscEnum*)&asmtype,&flg);CHKERRQ(ierr);
  if (flg) nasm->type = asmtype;
  flg    = PETSC_FALSE;
  monflg = PETSC_TRUE;
  ierr   = PetscOptionsReal("-snes_nasm_damping","Log times for subSNES solves and restriction","SNESNASMSetDamping",nasm->damping,&nasm->damping,&flg);CHKERRQ(ierr);
  if (flg) {ierr = SNESNASMSetDamping(snes,nasm->damping);CHKERRQ(ierr);}
  subviewflg = PETSC_FALSE;
  ierr   = PetscOptionsBool("-snes_nasm_sub_view","Print detailed information for every processor when using -snes_view","",subviewflg,&subviewflg,&flg);CHKERRQ(ierr);
  if (flg) {
    nasm->same_local_solves = PETSC_FALSE;
    if (!subviewflg) {
      nasm->same_local_solves = PETSC_TRUE;
    }
  }
  ierr   = PetscOptionsBool("-snes_nasm_finaljacobian","Compute the global jacobian of the final iterate (for ASPIN)","",nasm->finaljacobian,&nasm->finaljacobian,NULL);CHKERRQ(ierr);
  ierr   = PetscOptionsEList("-snes_nasm_finaljacobian_type","The type of the final jacobian computed.","",SNESNASMFJTypes,3,SNESNASMFJTypes[0],&nasm->fjtype,NULL);CHKERRQ(ierr);
  ierr   = PetscOptionsBool("-snes_nasm_log","Log times for subSNES solves and restriction","",monflg,&monflg,&flg);CHKERRQ(ierr);
  if (flg) {
    ierr = PetscLogEventRegister("SNESNASMSubSolve",((PetscObject)snes)->classid,&nasm->eventsubsolve);CHKERRQ(ierr);
    ierr = PetscLogEventRegister("SNESNASMRestrict",((PetscObject)snes)->classid,&nasm->eventrestrictinterp);CHKERRQ(ierr);
  }
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

/*@
   MatColoringSetFromOptions - Sets MatColoring options from user parameters

   Collective on MatColoring

   Input Parameters:
.  mc - MatColoring context

   Options Database Keys:
+   -mat_coloring_type - the type of coloring algorithm used
.   -mat_coloring_maxcolors - the maximum number of relevant colors, all nodes not in a color are in maxcolors+1
.   -mat_coloring_distance - compute a distance 1,2,... coloring.
.   -mat_coloring_view - print information about the coloring and the produced index sets

   Level: beginner

.keywords: Coloring, Matrix

.seealso: MatColoring, MatColoringApply()
@*/
PetscErrorCode MatColoringSetFromOptions(MatColoring mc)
{
  PetscBool      flg;
  MatColoringType deft        = MATCOLORINGSL;
  char           type[256];
  PetscErrorCode ierr;
  PetscInt       dist,maxcolors;
  PetscFunctionBegin;

  PetscValidHeaderSpecific(mc,MAT_COLORING_CLASSID,1);
  ierr = MatColoringGetDistance(mc,&dist);CHKERRQ(ierr);
  ierr = MatColoringGetMaxColors(mc,&maxcolors);CHKERRQ(ierr);
  if (!MatColoringRegisterAllCalled) {ierr = MatColoringRegisterAll();CHKERRQ(ierr);}
  ierr = PetscObjectOptionsBegin((PetscObject)mc);CHKERRQ(ierr);
  if (((PetscObject)mc)->type_name) deft = ((PetscObject)mc)->type_name;
  ierr = PetscOptionsFList("-mat_coloring_type","The coloring method used","MatColoringSetType",MatColoringList,deft,type,256,&flg);CHKERRQ(ierr);
  if (flg) {
    ierr = MatColoringSetType(mc,type);CHKERRQ(ierr);
  } else if (!((PetscObject)mc)->type_name) {
    ierr = MatColoringSetType(mc,deft);CHKERRQ(ierr);
  }
  ierr = PetscOptionsInt("-mat_coloring_distance","Distance of the coloring","MatColoringSetDistance",dist,&dist,&flg);CHKERRQ(ierr);
  if (flg) {ierr = MatColoringSetDistance(mc,dist);CHKERRQ(ierr);}
  ierr = PetscOptionsInt("-mat_coloring_maxcolors","Maximum colors returned at the end. 1 returns an independent set","MatColoringSetMaxColors",maxcolors,&maxcolors,&flg);CHKERRQ(ierr);
  if (flg) {ierr = MatColoringSetMaxColors(mc,maxcolors);CHKERRQ(ierr);}
  if (mc->ops->setfromoptions) {
    ierr = (*mc->ops->setfromoptions)(mc);CHKERRQ(ierr);
  }
  ierr = PetscOptionsBool("-mat_coloring_valid","Check that a valid coloring has been produced","",mc->valid,&mc->valid,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-mat_coloring_weight_type","Sets the type of vertex weighting used","MatColoringSetWeightType",MatColoringWeightTypes,(PetscEnum)mc->weight_type,(PetscEnum*)&mc->weight_type,NULL);CHKERRQ(ierr);
  ierr = PetscObjectProcessOptionsHandlers((PetscObject)mc);CHKERRQ(ierr);
  ierr = PetscOptionsEnd();CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

PetscErrorCode KSPSetFromOptions_GMRES(KSP ksp)
{
  PetscErrorCode ierr;
  PetscInt       restart;
  PetscReal      haptol;
  KSP_GMRES      *gmres = (KSP_GMRES*)ksp->data;
  PetscBool      flg;

  PetscFunctionBegin;
  ierr = PetscOptionsHead("KSP GMRES Options");CHKERRQ(ierr);
  ierr = PetscOptionsInt("-ksp_gmres_restart","Number of Krylov search directions","KSPGMRESSetRestart",gmres->max_k,&restart,&flg);CHKERRQ(ierr);
  if (flg) { ierr = KSPGMRESSetRestart(ksp,restart);CHKERRQ(ierr); }
  ierr = PetscOptionsReal("-ksp_gmres_haptol","Tolerance for exact convergence (happy ending)","KSPGMRESSetHapTol",gmres->haptol,&haptol,&flg);CHKERRQ(ierr);
  if (flg) { ierr = KSPGMRESSetHapTol(ksp,haptol);CHKERRQ(ierr); }
  flg  = PETSC_FALSE;
  ierr = PetscOptionsBool("-ksp_gmres_preallocate","Preallocate Krylov vectors","KSPGMRESSetPreAllocateVectors",flg,&flg,NULL);CHKERRQ(ierr);
  if (flg) {ierr = KSPGMRESSetPreAllocateVectors(ksp);CHKERRQ(ierr);}
  ierr = PetscOptionsBoolGroupBegin("-ksp_gmres_classicalgramschmidt","Classical (unmodified) Gram-Schmidt (fast)","KSPGMRESSetOrthogonalization",&flg);CHKERRQ(ierr);
  if (flg) {ierr = KSPGMRESSetOrthogonalization(ksp,KSPGMRESClassicalGramSchmidtOrthogonalization);CHKERRQ(ierr);}
  ierr = PetscOptionsBoolGroupEnd("-ksp_gmres_modifiedgramschmidt","Modified Gram-Schmidt (slow,more stable)","KSPGMRESSetOrthogonalization",&flg);CHKERRQ(ierr);
  if (flg) {ierr = KSPGMRESSetOrthogonalization(ksp,KSPGMRESModifiedGramSchmidtOrthogonalization);CHKERRQ(ierr);}
  ierr = PetscOptionsEnum("-ksp_gmres_cgs_refinement_type","Type of iterative refinement for classical (unmodified) Gram-Schmidt","KSPGMRESSetCGSRefinementType",
                          KSPGMRESCGSRefinementTypes,(PetscEnum)gmres->cgstype,(PetscEnum*)&gmres->cgstype,&flg);CHKERRQ(ierr);
  flg  = PETSC_FALSE;
  ierr = PetscOptionsBool("-ksp_gmres_krylov_monitor","Plot the Krylov directions","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr);
  if (flg) {
    PetscViewers viewers;
    ierr = PetscViewersCreate(PetscObjectComm((PetscObject)ksp),&viewers);CHKERRQ(ierr);
    ierr = KSPMonitorSet(ksp,KSPGMRESMonitorKrylov,viewers,(PetscErrorCode (*)(void**))PetscViewersDestroy);CHKERRQ(ierr);
  }
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

/*@
   PetscBagSetFromOptions - Allows setting options from a bag

   Collective on PetscBag

   Input Parameter:
.  bag - the bag of values

   Level: beginner

.seealso: PetscBag, PetscBagSetName(), PetscBagDestroy(), PetscBagLoad(), PetscBagGetData()
           PetscBagRegisterReal(), PetscBagRegisterInt(), PetscBagRegisterBool(), PetscBagRegisterScalar()
           PetscBagSetFromOptions(), PetscBagCreate(), PetscBagGetName(), PetscBagView(), PetscBagRegisterEnum()

@*/
PetscErrorCode  PetscBagSetFromOptions(PetscBag bag)
{
  PetscErrorCode ierr;
  PetscBagItem   nitem = bag->bagitems;
  char           name[PETSC_BAG_NAME_LENGTH+1],helpname[PETSC_BAG_NAME_LENGTH+PETSC_BAG_HELP_LENGTH+3];
  PetscInt       n;

  PetscFunctionBegin;
  ierr = PetscStrcpy(helpname,bag->bagname);CHKERRQ(ierr);
  ierr = PetscStrcat(helpname," ");CHKERRQ(ierr);
  ierr = PetscStrcat(helpname,bag->baghelp);CHKERRQ(ierr);
  ierr = PetscOptionsBegin(bag->bagcomm,bag->bagprefix,helpname,0);CHKERRQ(ierr);
  while (nitem) {
    name[0] = '-';
    name[1] = 0;
    ierr    = PetscStrcat(name,nitem->name);CHKERRQ(ierr);
    if (nitem->dtype == PETSC_CHAR) {   /* special handling for fortran required? [due to space padding vs null termination] */
      char *value = (char*)(((char*)bag) + nitem->offset);
      ierr = PetscOptionsString(name,nitem->help,"",value,value,nitem->msize,NULL);CHKERRQ(ierr);
    } else if (nitem->dtype == PETSC_REAL) {
      PetscReal *value = (PetscReal*)(((char*)bag) + nitem->offset);
      if (nitem->msize == 1) {
        ierr = PetscOptionsReal(name,nitem->help,"",*value,value,NULL);CHKERRQ(ierr);
      } else {
        n    = nitem->msize;
        ierr = PetscOptionsRealArray(name,nitem->help,"",value,&n,NULL);CHKERRQ(ierr);
      }
    } else if (nitem->dtype == PETSC_SCALAR) {
      PetscScalar *value = (PetscScalar*)(((char*)bag) + nitem->offset);
      ierr = PetscOptionsScalar(name,nitem->help,"",*value,value,NULL);CHKERRQ(ierr);
    } else if (nitem->dtype == PETSC_INT) {
      PetscInt *value = (PetscInt*)(((char*)bag) + nitem->offset);
      if (nitem->msize == 1) {
        ierr = PetscOptionsInt(name,nitem->help,"",*value,value,NULL);CHKERRQ(ierr);
      } else {
        n    = nitem->msize;
        ierr = PetscOptionsIntArray(name,nitem->help,"",value,&n,NULL);CHKERRQ(ierr);
      }
    } else if (nitem->dtype == PETSC_ENUM) {
      PetscEnum *value = (PetscEnum*)(((char*)bag) + nitem->offset);
      PetscInt  i      = 0;
      while (nitem->list[i++]) ;
      ierr = PetscOptionsEnum(name,nitem->help,nitem->list[i-3],(const char*const*)nitem->list,*value,value,NULL);CHKERRQ(ierr);
    } else if (nitem->dtype == PETSC_BOOL) {
      PetscBool *value = (PetscBool*)(((char*)bag) + nitem->offset);
      if (nitem->msize == 1) {
        ierr = PetscOptionsBool(name,nitem->help,"",*value,value,NULL);CHKERRQ(ierr);
      } else {
        n = nitem->msize;
        ierr = PetscOptionsBoolArray(name,nitem->help,"",value,&n,NULL);CHKERRQ(ierr);
      }
    }
    nitem = nitem->next;
  }
  PetscOptionsEnd();
  PetscFunctionReturn(0);
}

PetscErrorCode  PCSetFromOptions_Factor(PC pc)
{
  PC_Factor         *factor = (PC_Factor*)pc->data;
  PetscErrorCode    ierr;
  PetscBool         flg = PETSC_FALSE,set;
  char              tname[256], solvertype[64];
  PetscFunctionList ordlist;
  PetscEnum         etmp;

  PetscFunctionBegin;
  if (!MatOrderingRegisterAllCalled) {ierr = MatOrderingRegisterAll();CHKERRQ(ierr);}
  ierr = PetscOptionsBool("-pc_factor_in_place","Form factored matrix in the same memory as the matrix","PCFactorSetUseInPlace",flg,&flg,NULL);CHKERRQ(ierr);
  if (flg) {
    ierr = PCFactorSetUseInPlace(pc);CHKERRQ(ierr);
  }
  ierr = PetscOptionsReal("-pc_factor_fill","Expected non-zeros in factored matrix","PCFactorSetFill",((PC_Factor*)factor)->info.fill,&((PC_Factor*)factor)->info.fill,0);CHKERRQ(ierr);

  ierr = PetscOptionsEnum("-pc_factor_shift_type","Type of shift to add to diagonal","PCFactorSetShiftType",
                          MatFactorShiftTypes,(PetscEnum)(int)((PC_Factor*)factor)->info.shifttype,&etmp,&flg);CHKERRQ(ierr);
  if (flg) {
    ierr = PCFactorSetShiftType(pc,(MatFactorShiftType)etmp);CHKERRQ(ierr);
  }
  ierr = PetscOptionsReal("-pc_factor_shift_amount","Shift added to diagonal","PCFactorSetShiftAmount",((PC_Factor*)factor)->info.shiftamount,&((PC_Factor*)factor)->info.shiftamount,0);CHKERRQ(ierr);

  ierr = PetscOptionsReal("-pc_factor_zeropivot","Pivot is considered zero if less than","PCFactorSetZeroPivot",((PC_Factor*)factor)->info.zeropivot,&((PC_Factor*)factor)->info.zeropivot,0);CHKERRQ(ierr);
  ierr = PetscOptionsReal("-pc_factor_column_pivot","Column pivot tolerance (used only for some factorization)","PCFactorSetColumnPivot",((PC_Factor*)factor)->info.dtcol,&((PC_Factor*)factor)->info.dtcol,&flg);CHKERRQ(ierr);

  flg  = ((PC_Factor*)factor)->info.pivotinblocks ? PETSC_TRUE : PETSC_FALSE;
  ierr = PetscOptionsBool("-pc_factor_pivot_in_blocks","Pivot inside matrix dense blocks for BAIJ and SBAIJ","PCFactorSetPivotInBlocks",flg,&flg,&set);CHKERRQ(ierr);
  if (set) {
    ierr = PCFactorSetPivotInBlocks(pc,flg);CHKERRQ(ierr);
  }

  flg  = PETSC_FALSE;
  ierr = PetscOptionsBool("-pc_factor_reuse_fill","Use fill from previous factorization","PCFactorSetReuseFill",flg,&flg,NULL);CHKERRQ(ierr);
  if (flg) {
    ierr = PCFactorSetReuseFill(pc,PETSC_TRUE);CHKERRQ(ierr);
  }
  flg  = PETSC_FALSE;
  ierr = PetscOptionsBool("-pc_factor_reuse_ordering","Reuse ordering from previous factorization","PCFactorSetReuseOrdering",flg,&flg,NULL);CHKERRQ(ierr);
  if (flg) {
    ierr = PCFactorSetReuseOrdering(pc,PETSC_TRUE);CHKERRQ(ierr);
  }

  ierr = MatGetOrderingList(&ordlist);CHKERRQ(ierr);
  ierr = PetscOptionsList("-pc_factor_mat_ordering_type","Reordering to reduce nonzeros in factored matrix","PCFactorSetMatOrderingType",ordlist,((PC_Factor*)factor)->ordering,tname,256,&flg);CHKERRQ(ierr);
  if (flg) {
    ierr = PCFactorSetMatOrderingType(pc,tname);CHKERRQ(ierr);
  }

  /* maybe should have MatGetSolverTypes(Mat,&list) like the ordering list */
  ierr = PetscOptionsString("-pc_factor_mat_solver_package","Specific direct solver to use","MatGetFactor",((PC_Factor*)factor)->solvertype,solvertype,64,&flg);CHKERRQ(ierr);
  if (flg) {
    ierr = PCFactorSetMatSolverPackage(pc,solvertype);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}

static PetscErrorCode PCSetFromOptions_PARMS(PC pc)
{
  PC_PARMS          *parms = (PC_PARMS*)pc->data;
  PetscBool         flag;
  PCPARMSGlobalType global;
  PCPARMSLocalType  local;
  PetscErrorCode    ierr;

  PetscFunctionBegin;
  ierr = PetscOptionsHead("PARMS Options");CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-pc_parms_global","Global preconditioner","PCPARMSSetGlobal",PCPARMSGlobalTypes,(PetscEnum)parms->global,(PetscEnum*)&global,&flag);CHKERRQ(ierr);
  if (flag) { ierr = PCPARMSSetGlobal(pc,global);CHKERRQ(ierr); }
  ierr = PetscOptionsEnum("-pc_parms_local","Local preconditioner","PCPARMSSetLocal",PCPARMSLocalTypes,(PetscEnum)parms->local,(PetscEnum*)&local,&flag);CHKERRQ(ierr);
  if (flag) { ierr = PCPARMSSetLocal(pc,local);CHKERRQ(ierr); }
  ierr = PetscOptionsReal("-pc_parms_solve_tol","Tolerance for local solve","PCPARMSSetSolveTolerances",parms->solvetol,&parms->solvetol,&flag);CHKERRQ(ierr);
  ierr = PetscOptionsInt("-pc_parms_levels","Number of levels","None",parms->levels,&parms->levels,&flag);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-pc_parms_nonsymmetric_perm","Use nonsymmetric permutation","PCPARMSSetNonsymPerm",parms->nonsymperm,&parms->nonsymperm,&flag);CHKERRQ(ierr);
  ierr = PetscOptionsInt("-pc_parms_blocksize","Block size","None",parms->blocksize,&parms->blocksize,&flag);CHKERRQ(ierr);
  ierr = PetscOptionsReal("-pc_parms_ind_tol","Tolerance for independent sets","None",parms->indtol,&parms->indtol,&flag);CHKERRQ(ierr);
  ierr = PetscOptionsInt("-pc_parms_max_dim","Inner Krylov dimension","PCPARMSSetSolveRestart",parms->maxdim,&parms->maxdim,&flag);CHKERRQ(ierr);
  ierr = PetscOptionsInt("-pc_parms_max_it","Maximum number of inner iterations","PCPARMSSetSolveTolerances",parms->maxits,&parms->maxits,&flag);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-pc_parms_inter_nonsymmetric_perm","nonsymmetric permutation for interlevel blocks","None",parms->meth[0],&parms->meth[0],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-pc_parms_inter_column_perm","column permutation for interlevel blocks","None",parms->meth[1],&parms->meth[1],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-pc_parms_inter_row_scaling","row scaling for interlevel blocks","None",parms->meth[2],&parms->meth[2],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-pc_parms_inter_column_scaling","column scaling for interlevel blocks","None",parms->meth[3],&parms->meth[3],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-pc_parms_last_nonsymmetric_perm","nonsymmetric permutation for last level blocks","None",parms->meth[4],&parms->meth[4],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-pc_parms_last_column_perm","column permutation for last level blocks","None",parms->meth[5],&parms->meth[5],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-pc_parms_last_row_scaling","row scaling for last level blocks","None",parms->meth[6],&parms->meth[6],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsBool("-pc_parms_last_column_scaling","column scaling for last level blocks","None",parms->meth[7],&parms->meth[7],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsInt("-pc_parms_lfil_ilu_arms","amount of fill-in for ilut, iluk and arms","PCPARMSSetFill",parms->lfil[0],&parms->lfil[0],&flag);CHKERRQ(ierr);
  if (flag) parms->lfil[1] = parms->lfil[2] = parms->lfil[3] = parms->lfil[0];
  ierr = PetscOptionsInt("-pc_parms_lfil_schur","amount of fill-in for schur","PCPARMSSetFill",parms->lfil[4],&parms->lfil[4],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsInt("-pc_parms_lfil_ilut_L_U","amount of fill-in for ILUT L and U","PCPARMSSetFill",parms->lfil[5],&parms->lfil[5],&flag);CHKERRQ(ierr);
  if (flag) parms->lfil[6] = parms->lfil[5];
  ierr = PetscOptionsReal("-pc_parms_droptol_factors","drop tolerance for L, U, L^{-1}F and EU^{-1}","None",parms->droptol[0],&parms->droptol[0],&flag);CHKERRQ(ierr);
  ierr = PetscOptionsReal("-pc_parms_droptol_schur_compl","drop tolerance for schur complement at each level","None",parms->droptol[4],&parms->droptol[4],&flag);CHKERRQ(ierr);
  if (flag) parms->droptol[1] = parms->droptol[2] = parms->droptol[3] = parms->droptol[0];
  ierr = PetscOptionsReal("-pc_parms_droptol_last_schur","drop tolerance for ILUT in last level schur complement","None",parms->droptol[5],&parms->droptol[5],&flag);CHKERRQ(ierr);
  if (flag) parms->droptol[6] = parms->droptol[5];
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

static PetscErrorCode PetscSFSetFromOptions_Window(PetscOptionItems *PetscOptionsObject,PetscSF sf)
{
  PetscSF_Window *w = (PetscSF_Window*)sf->data;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  ierr = PetscOptionsHead(PetscOptionsObject,"PetscSF Window options");CHKERRQ(ierr);
  ierr = PetscOptionsEnum("-sf_window_sync","synchronization type to use for PetscSF Window communication","PetscSFWindowSetSyncType",PetscSFWindowSyncTypes,(PetscEnum)w->sync,(PetscEnum*)&w->sync,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsTail();CHKERRQ(ierr);
  PetscFunctionReturn(0);
}