// -------------------------------------------------------------
// PETScConfigurable::p_unprocessOptions
// -------------------------------------------------------------
void
PETScConfigurable::p_unprocessOptions(void)
{
  boost::char_separator<char> sep(" \t\f\n\r\v", "");
  boost::tokenizer<boost::char_separator<char> > 
    opttok(p_loadedOptions, sep);
  boost::tokenizer<boost::char_separator<char> >::iterator o;
  for (o = opttok.begin(); o != opttok.end(); ++o) {
    if ((*o)[0] == '-' && islower((*o)[1])) {
      PetscErrorCode ierr(0);
      try {
        if (verbose) {
          std::cout << "p_unprocessOptions: removing \"" 
                    << *o << "\"" << std::endl;
        }
        ierr = PetscOptionsClearValue(
#if PETSC_VERSION_GE(3,7,0)
                                    NULL,
#endif
                                    o->c_str());
      } catch (const PETSC_EXCEPTION_TYPE& e) {
        throw PETScException(ierr, e);
      }
    }
  } 
  p_loadedOptions.clear();
}
Beispiel #2
0
static PetscErrorCode KSPComputeShifts_GMRES(KSP ksp)
{
  PetscErrorCode ierr;
  KSP_AGMRES     *agmres = (KSP_AGMRES*)(ksp->data);
  KSP            kspgmres;
  Mat            Amat, Pmat;
  MatStructure   flag;
  PetscInt       max_k = agmres->max_k;
  PC             pc;
  PetscInt       m;
  PetscScalar    *Rshift, *Ishift;


  PetscFunctionBegin;
  /* Perform one cycle of classical GMRES (with the Arnoldi process) to get the Hessenberg matrix
   We assume here that the ksp is AGMRES and that the operators for the
   linear system have been set in this ksp */
  ierr = KSPCreate(PetscObjectComm((PetscObject)ksp), &kspgmres);CHKERRQ(ierr);
  if (!ksp->pc) { ierr = KSPGetPC(ksp,&ksp->pc);CHKERRQ(ierr); }
  ierr = PCGetOperators(ksp->pc, &Amat, &Pmat);CHKERRQ(ierr);
  ierr = KSPSetOperators(kspgmres, Amat, Pmat);CHKERRQ(ierr);
  ierr = KSPSetFromOptions(kspgmres);CHKERRQ(ierr);
  ierr = PetscOptionsHasName(NULL, "-ksp_view", &flg);CHKERRQ(ierr);
  if (flag) { ierr = PetscOptionsClearValue("-ksp_view");CHKERRQ(ierr); }
  ierr = KSPSetType(kspgmres, KSPGMRES);CHKERRQ(ierr);
  ierr = KSPGMRESSetRestart(kspgmres, max_k);CHKERRQ(ierr);
  ierr = KSPGetPC(ksp, &pc);CHKERRQ(ierr);
  ierr = KSPSetPC(kspgmres, pc);CHKERRQ(ierr);
  /* Copy common options */
  kspgmres->pc_side = ksp->pc_side;
  /* Setup KSP context */
  ierr = KSPSetComputeEigenvalues(kspgmres, PETSC_TRUE);CHKERRQ(ierr);
  ierr = KSPSetUp(kspgmres);CHKERRQ(ierr);

  kspgmres->max_it = max_k; /* Restrict the maximum number of iterations to one cycle of GMRES */
  kspgmres->rtol   = ksp->rtol;

  ierr = KSPSolve(kspgmres, ksp->vec_rhs, ksp->vec_sol);CHKERRQ(ierr);

  ksp->guess_zero = PETSC_FALSE;
  ksp->rnorm      = kspgmres->rnorm;
  ksp->its        = kspgmres->its;
  if (kspgmres->reason == KSP_CONVERGED_RTOL) {
    ksp->reason = KSP_CONVERGED_RTOL;
    PetscFunctionReturn(0);
  } else ksp->reason = KSP_CONVERGED_ITERATING;
  /* Now, compute the Shifts values */
  ierr = PetscMalloc2(max_k,&Rshift,max_k,&Ishift);CHKERRQ(ierr);
  ierr = KSPComputeEigenvalues(kspgmres, max_k, Rshift, Ishift, &m);CHKERRQ(ierr);
  if (m < max_k) SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_PLIB, "Unable to compute the Shifts for the Newton basis");
  else {
    ierr = KSPAGMRESLejaOrdering(Rshift, Ishift, agmres->Rshift, agmres->Ishift, max_k);CHKERRQ(ierr);

    agmres->HasShifts = PETSC_TRUE;
  }
  /* Restore KSP view options */
  if (flg) { ierr = PetscOptionsSetValue("-ksp_view", "");CHKERRQ(ierr); }
  PetscFunctionReturn(0);
}
Beispiel #3
0
int main(int argc,char **args)
{
  Mat            Amat;
  PetscErrorCode ierr;
  SNES           snes;
  KSP            ksp;
  MPI_Comm       comm;
  PetscMPIInt    npe,rank;
  PetscLogStage  stage[7];
  PetscBool      test_nonzero_cols=PETSC_FALSE,use_nearnullspace=PETSC_TRUE;
  Vec            xx,bb;
  PetscInt       iter,i,N,dim=3,cells[3]={1,1,1},max_conv_its,local_sizes[7],run_type=1;
  DM             dm,distdm,basedm;
  PetscBool      flg;
  char           convType[256];
  PetscReal      Lx,mdisp[10],err[10];
  const char * const options[10] = {"-ex56_dm_refine 0",
                                    "-ex56_dm_refine 1",
                                    "-ex56_dm_refine 2",
                                    "-ex56_dm_refine 3",
                                    "-ex56_dm_refine 4",
                                    "-ex56_dm_refine 5",
                                    "-ex56_dm_refine 6",
                                    "-ex56_dm_refine 7",
                                    "-ex56_dm_refine 8",
                                    "-ex56_dm_refine 9"};
  PetscFunctionBeginUser;
  ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
  comm = PETSC_COMM_WORLD;
  ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr);
  ierr = MPI_Comm_size(comm, &npe);CHKERRQ(ierr);
  /* options */
  ierr = PetscOptionsBegin(comm,NULL,"3D bilinear Q1 elasticity options","");CHKERRQ(ierr);
  {
    i = 3;
    ierr = PetscOptionsIntArray("-cells", "Number of (flux tube) processor in each dimension", "ex56.c", cells, &i, NULL);CHKERRQ(ierr);

    Lx = 1.; /* or ne for rod */
    max_conv_its = 3;
    ierr = PetscOptionsInt("-max_conv_its","Number of iterations in convergence study","",max_conv_its,&max_conv_its,NULL);CHKERRQ(ierr);
    if (max_conv_its<=0 || max_conv_its>7) SETERRQ1(PETSC_COMM_WORLD, PETSC_ERR_USER, "Bad number of iterations for convergence test (%D)",max_conv_its);
    ierr = PetscOptionsReal("-lx","Length of domain","",Lx,&Lx,NULL);CHKERRQ(ierr);
    ierr = PetscOptionsReal("-alpha","material coefficient inside circle","",s_soft_alpha,&s_soft_alpha,NULL);CHKERRQ(ierr);
    ierr = PetscOptionsBool("-test_nonzero_cols","nonzero test","",test_nonzero_cols,&test_nonzero_cols,NULL);CHKERRQ(ierr);
    ierr = PetscOptionsBool("-use_mat_nearnullspace","MatNearNullSpace API test","",use_nearnullspace,&use_nearnullspace,NULL);CHKERRQ(ierr);
    ierr = PetscOptionsInt("-run_type","0: twisting load on cantalever, 1: 3rd order accurate convergence test","",run_type,&run_type,NULL);CHKERRQ(ierr);
    i = 3;
    ierr = PetscOptionsInt("-mat_block_size","","",i,&i,&flg);CHKERRQ(ierr);
    if (!flg || i!=3) SETERRQ2(PETSC_COMM_WORLD, PETSC_ERR_USER, "'-mat_block_size 3' must be set (%D) and = 3 (%D)",flg,flg? i : 3);
  }
  ierr = PetscOptionsEnd();CHKERRQ(ierr);
  ierr = PetscLogStageRegister("Mesh Setup", &stage[6]);CHKERRQ(ierr);
  ierr = PetscLogStageRegister("1st Setup", &stage[0]);CHKERRQ(ierr);
  ierr = PetscLogStageRegister("1st Solve", &stage[1]);CHKERRQ(ierr);

  /* create DM, Plex calls DMSetup */
  ierr = PetscLogStagePush(stage[6]);CHKERRQ(ierr);
  ierr = DMPlexCreateHexBoxMesh(comm, dim, cells, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, &dm);CHKERRQ(ierr);
  {
    DMLabel         label;
    IS              is;
    ierr = DMCreateLabel(dm, "boundary");CHKERRQ(ierr);
    ierr = DMGetLabel(dm, "boundary", &label);CHKERRQ(ierr);
    ierr = DMPlexMarkBoundaryFaces(dm, label);CHKERRQ(ierr);
    if (run_type==0) {
      ierr = DMGetStratumIS(dm, "boundary", 1,  &is);CHKERRQ(ierr);
      ierr = DMCreateLabel(dm,"Faces");CHKERRQ(ierr);
      if (is) {
        PetscInt        d, f, Nf;
        const PetscInt *faces;
        PetscInt        csize;
        PetscSection    cs;
        Vec             coordinates ;
        DM              cdm;
        ierr = ISGetLocalSize(is, &Nf);CHKERRQ(ierr);
        ierr = ISGetIndices(is, &faces);CHKERRQ(ierr);
        ierr = DMGetCoordinatesLocal(dm, &coordinates);CHKERRQ(ierr);
        ierr = DMGetCoordinateDM(dm, &cdm);CHKERRQ(ierr);
        ierr = DMGetDefaultSection(cdm, &cs);CHKERRQ(ierr);
        /* Check for each boundary face if any component of its centroid is either 0.0 or 1.0 */
        for (f = 0; f < Nf; ++f) {
          PetscReal   faceCoord;
          PetscInt    b,v;
          PetscScalar *coords = NULL;
          PetscInt    Nv;
          ierr = DMPlexVecGetClosure(cdm, cs, coordinates, faces[f], &csize, &coords);CHKERRQ(ierr);
          Nv   = csize/dim; /* Calculate mean coordinate vector */
          for (d = 0; d < dim; ++d) {
            faceCoord = 0.0;
            for (v = 0; v < Nv; ++v) faceCoord += PetscRealPart(coords[v*dim+d]);
            faceCoord /= Nv;
            for (b = 0; b < 2; ++b) {
              if (PetscAbs(faceCoord - b) < PETSC_SMALL) { /* domain have not been set yet, still [0,1]^3 */
                ierr = DMSetLabelValue(dm, "Faces", faces[f], d*2+b+1);CHKERRQ(ierr);
              }
            }
          }
          ierr = DMPlexVecRestoreClosure(cdm, cs, coordinates, faces[f], &csize, &coords);CHKERRQ(ierr);
        }
        ierr = ISRestoreIndices(is, &faces);CHKERRQ(ierr);
      }
      ierr = ISDestroy(&is);CHKERRQ(ierr);
      ierr = DMGetLabel(dm, "Faces", &label);CHKERRQ(ierr);
      ierr = DMPlexLabelComplete(dm, label);CHKERRQ(ierr);
    }
  }
  {
    PetscInt dimEmbed, i;
    PetscInt nCoords;
    PetscScalar *coords,bounds[] = {0,Lx,-.5,.5,-.5,.5,}; /* x_min,x_max,y_min,y_max */
    Vec coordinates;
    if (run_type==1) {
      for (i = 0; i < 2*dim; i++) bounds[i] = (i%2) ? 1 : 0;
    }
    ierr = DMGetCoordinatesLocal(dm,&coordinates);CHKERRQ(ierr);
    ierr = DMGetCoordinateDim(dm,&dimEmbed);CHKERRQ(ierr);
    if (dimEmbed != dim) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"dimEmbed != dim %D",dimEmbed);CHKERRQ(ierr);
    ierr = VecGetLocalSize(coordinates,&nCoords);CHKERRQ(ierr);
    if (nCoords % dimEmbed) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Coordinate vector the wrong size");CHKERRQ(ierr);
    ierr = VecGetArray(coordinates,&coords);CHKERRQ(ierr);
    for (i = 0; i < nCoords; i += dimEmbed) {
      PetscInt j;
      PetscScalar *coord = &coords[i];
      for (j = 0; j < dimEmbed; j++) {
        coord[j] = bounds[2 * j] + coord[j] * (bounds[2 * j + 1] - bounds[2 * j]);
      }
    }
    ierr = VecRestoreArray(coordinates,&coords);CHKERRQ(ierr);
    ierr = DMSetCoordinatesLocal(dm,coordinates);CHKERRQ(ierr);
  }

  /* convert to p4est, and distribute */

  ierr = PetscOptionsBegin(comm, "", "Mesh conversion options", "DMPLEX");CHKERRQ(ierr);
  ierr = PetscOptionsFList("-dm_type","Convert DMPlex to another format (should not be Plex!)","ex56.c",DMList,DMPLEX,convType,256,&flg);CHKERRQ(ierr);
  ierr = PetscOptionsEnd();
  if (flg) {
    DM newdm;
    ierr = DMConvert(dm,convType,&newdm);CHKERRQ(ierr);
    if (newdm) {
      const char *prefix;
      PetscBool isForest;
      ierr = PetscObjectGetOptionsPrefix((PetscObject)dm,&prefix);CHKERRQ(ierr);
      ierr = PetscObjectSetOptionsPrefix((PetscObject)newdm,prefix);CHKERRQ(ierr);
      ierr = DMIsForest(newdm,&isForest);CHKERRQ(ierr);
      if (isForest) {
      } else SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_USER, "Converted to non Forest?");
      ierr = DMDestroy(&dm);CHKERRQ(ierr);
      dm   = newdm;
    } else SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_USER, "Convert failed?");
  } else {
    /* Plex Distribute mesh over processes */
    ierr = DMPlexDistribute(dm, 0, NULL, &distdm);CHKERRQ(ierr);
    if (distdm) {
      const char *prefix;
      ierr = PetscObjectGetOptionsPrefix((PetscObject)dm,&prefix);CHKERRQ(ierr);
      ierr = PetscObjectSetOptionsPrefix((PetscObject)distdm,prefix);CHKERRQ(ierr);
      ierr = DMDestroy(&dm);CHKERRQ(ierr);
      dm   = distdm;
    }
  }
  ierr = PetscLogStagePop();CHKERRQ(ierr);
  basedm = dm; dm = NULL;

  for (iter=0 ; iter<max_conv_its ; iter++) {
    ierr = PetscLogStagePush(stage[6]);CHKERRQ(ierr);
    /* make new DM */
    ierr = DMClone(basedm, &dm);CHKERRQ(ierr);
    ierr = PetscObjectSetOptionsPrefix((PetscObject) dm, "ex56_");CHKERRQ(ierr);
    ierr = PetscObjectSetName( (PetscObject)dm,"Mesh");CHKERRQ(ierr);
    ierr = PetscOptionsClearValue(NULL,"-ex56_dm_refine");CHKERRQ(ierr);
    ierr = PetscOptionsInsertString(NULL,options[iter]);CHKERRQ(ierr);
    ierr = DMSetFromOptions(dm);CHKERRQ(ierr); /* refinement done here in Plex, p4est */
    /* snes */
    ierr = SNESCreate(comm, &snes);CHKERRQ(ierr);
    ierr = SNESSetDM(snes, dm);CHKERRQ(ierr);
    /* fem */
    {
      const PetscInt Ncomp = dim;
      const PetscInt components[] = {0,1,2};
      const PetscInt Nfid = 1, Npid = 1;
      const PetscInt fid[] = {1}; /* The fixed faces (x=0) */
      const PetscInt pid[] = {2}; /* The faces with loading (x=L_x) */
      PetscFE         fe;
      PetscDS         prob;
      DM              cdm = dm;

      ierr = PetscFECreateDefault(dm, dim, dim, PETSC_FALSE, NULL, PETSC_DECIDE, &fe);CHKERRQ(ierr); /* elasticity */
      ierr = PetscObjectSetName((PetscObject) fe, "deformation");CHKERRQ(ierr);
      /* FEM prob */
      ierr = DMGetDS(dm, &prob);CHKERRQ(ierr);
      ierr = PetscDSSetDiscretization(prob, 0, (PetscObject) fe);CHKERRQ(ierr);
      /* setup problem */
      if (run_type==1) {
        ierr = PetscDSSetJacobian(prob, 0, 0, NULL, NULL, NULL, g3_uu_3d);CHKERRQ(ierr);
        ierr = PetscDSSetResidual(prob, 0, f0_u_x4, f1_u_3d);CHKERRQ(ierr);
      } else {
        ierr = PetscDSSetJacobian(prob, 0, 0, NULL, NULL, NULL, g3_uu_3d_alpha);CHKERRQ(ierr);
        ierr = PetscDSSetResidual(prob, 0, f0_u, f1_u_3d_alpha);CHKERRQ(ierr);
        ierr = PetscDSSetBdResidual(prob, 0, f0_bd_u_3d, f1_bd_u);CHKERRQ(ierr);
      }
      /* bcs */
      if (run_type==1) {
        PetscInt id = 1;
        ierr = DMAddBoundary(dm, DM_BC_ESSENTIAL, "wall", "boundary", 0, 0, NULL, (void (*)()) zero, 1, &id, NULL);CHKERRQ(ierr);
      } else {
        ierr = PetscDSAddBoundary(prob, DM_BC_ESSENTIAL, "fixed", "Faces", 0, Ncomp, components, (void (*)()) zero, Nfid, fid, NULL);CHKERRQ(ierr);
        ierr = PetscDSAddBoundary(prob, DM_BC_NATURAL, "traction", "Faces", 0, Ncomp, components, NULL, Npid, pid, NULL);CHKERRQ(ierr);
      }
      while (cdm) {
        ierr = DMSetDS(cdm,prob);CHKERRQ(ierr);
        ierr = DMGetCoarseDM(cdm, &cdm);CHKERRQ(ierr);
      }
      ierr = PetscFEDestroy(&fe);CHKERRQ(ierr);
    }
    /* vecs & mat */
    ierr = DMCreateGlobalVector(dm,&xx);CHKERRQ(ierr);
    ierr = VecDuplicate(xx, &bb);CHKERRQ(ierr);
    ierr = PetscObjectSetName((PetscObject) bb, "b");CHKERRQ(ierr);
    ierr = PetscObjectSetName((PetscObject) xx, "u");CHKERRQ(ierr);
    ierr = DMCreateMatrix(dm, &Amat);CHKERRQ(ierr);
    ierr = VecGetSize(bb,&N);CHKERRQ(ierr);
    local_sizes[iter] = N;
    ierr = PetscPrintf(PETSC_COMM_WORLD,"[%d]%s %d global equations, %d vertices\n",rank,PETSC_FUNCTION_NAME,N,N/dim);CHKERRQ(ierr);
    if (use_nearnullspace && N/dim > 1) {
      /* Set up the near null space (a.k.a. rigid body modes) that will be used by the multigrid preconditioner */
      DM           subdm;
      MatNullSpace nearNullSpace;
      PetscInt     fields = 0;
      PetscObject  deformation;
      ierr = DMCreateSubDM(dm, 1, &fields, NULL, &subdm);CHKERRQ(ierr);
      ierr = DMPlexCreateRigidBody(subdm, &nearNullSpace);CHKERRQ(ierr);
      ierr = DMGetField(dm, 0, &deformation);CHKERRQ(ierr);
      ierr = PetscObjectCompose(deformation, "nearnullspace", (PetscObject) nearNullSpace);CHKERRQ(ierr);
      ierr = DMDestroy(&subdm);CHKERRQ(ierr);
      ierr = MatNullSpaceDestroy(&nearNullSpace);CHKERRQ(ierr); /* created by DM and destroyed by Mat */
    }
    ierr = DMPlexSetSNESLocalFEM(dm,NULL,NULL,NULL);CHKERRQ(ierr);
    ierr = SNESSetJacobian(snes, Amat, Amat, NULL, NULL);CHKERRQ(ierr);
    ierr = SNESSetFromOptions(snes);CHKERRQ(ierr);
    ierr = DMSetUp(dm);CHKERRQ(ierr);
    ierr = PetscLogStagePop();CHKERRQ(ierr);
    ierr = PetscLogStagePush(stage[0]);CHKERRQ(ierr);
    /* ksp */
    ierr = SNESGetKSP(snes, &ksp);CHKERRQ(ierr);
    ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr);
    /* test BCs */
    ierr = VecZeroEntries(xx);CHKERRQ(ierr);
    if (test_nonzero_cols) {
      if (rank==0) ierr = VecSetValue(xx,0,1.0,INSERT_VALUES);CHKERRQ(ierr);
      ierr = VecAssemblyBegin(xx);CHKERRQ(ierr);
      ierr = VecAssemblyEnd(xx);CHKERRQ(ierr);
    }
    ierr = VecZeroEntries(bb);CHKERRQ(ierr);
    ierr = VecGetSize(bb,&i);CHKERRQ(ierr);
    local_sizes[iter] = i;
    ierr = PetscPrintf(PETSC_COMM_WORLD,"[%d]%s %d equations in vector, %d vertices\n",rank,PETSC_FUNCTION_NAME,i,i/dim);CHKERRQ(ierr);
    /* setup solver, dummy solve to really setup */
    if (0) {
      ierr = KSPSetTolerances(ksp,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,1);CHKERRQ(ierr);
      ierr = SNESSolve(snes, bb, xx);CHKERRQ(ierr);
      ierr = KSPSetTolerances(ksp,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,50);CHKERRQ(ierr);
      ierr = VecZeroEntries(xx);CHKERRQ(ierr);
    }
    ierr = PetscLogStagePop();CHKERRQ(ierr);
    /* solve */
    ierr = PetscLogStagePush(stage[1]);CHKERRQ(ierr);
    ierr = SNESSolve(snes, bb, xx);CHKERRQ(ierr);
    ierr = PetscLogStagePop();CHKERRQ(ierr);
    ierr = VecNorm(xx,NORM_INFINITY,&mdisp[iter]);CHKERRQ(ierr);
    ierr = DMViewFromOptions(dm, NULL, "-dm_view");CHKERRQ(ierr);
    {
      PetscViewer       viewer = NULL;
      PetscViewerFormat fmt;
      ierr = PetscOptionsGetViewer(comm,"ex56_","-vec_view",&viewer,&fmt,&flg);CHKERRQ(ierr);
      if (flg) {
        ierr = PetscViewerPushFormat(viewer,fmt);CHKERRQ(ierr);
        ierr = VecView(xx,viewer);CHKERRQ(ierr);
        ierr = VecView(bb,viewer);CHKERRQ(ierr);
        ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
      }
      ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
    }
    /* Free work space */
    ierr = DMDestroy(&dm);CHKERRQ(ierr);
    ierr = SNESDestroy(&snes);CHKERRQ(ierr);
    ierr = VecDestroy(&xx);CHKERRQ(ierr);
    ierr = VecDestroy(&bb);CHKERRQ(ierr);
    ierr = MatDestroy(&Amat);CHKERRQ(ierr);
  }
  ierr = DMDestroy(&basedm);CHKERRQ(ierr);
  if (run_type==1) {
    err[0] = 59.975208 - mdisp[0]; /* error with what I think is the exact solution */
  } else {
    err[0] = 171.038 - mdisp[0];
  }
  for (iter=1 ; iter<max_conv_its ; iter++) {
    if (run_type==1) {
      err[iter] = 59.975208 - mdisp[iter];
    } else {
      err[iter] = 171.038 - mdisp[iter];
    }
    PetscPrintf(PETSC_COMM_WORLD,"[%d]%s %D) N=%12D, max displ=%9.7e, disp diff=%9.2e, error=%4.3e, rate=%3.2g\n",
                rank,PETSC_FUNCTION_NAME,iter,local_sizes[iter],mdisp[iter],
                mdisp[iter]-mdisp[iter-1],err[iter],log(err[iter-1]/err[iter])/log(2.));
  }

  ierr = PetscFinalize();
  return ierr;
}