Esempio n. 1
0
PetscErrorCode PETSCSNES_DLLEXPORT DMMGSetUpLevel(DMMG *dmmg,KSP ksp,PetscInt nlevels)
{
  PetscErrorCode          ierr;
  PetscInt                i;
  PC                      pc;
  PetscTruth              ismg,ismf,isshell,ismffd;
  KSP                     lksp; /* solver internal to the multigrid preconditioner */
  MPI_Comm                *comms;

  PetscFunctionBegin;
  if (!dmmg) SETERRQ(PETSC_ERR_ARG_NULL,"Passing null as DMMG");

  /* use fgmres on outer iteration by default */
  ierr  = KSPSetType(ksp,KSPFGMRES);CHKERRQ(ierr);
  ierr  = KSPGetPC(ksp,&pc);CHKERRQ(ierr);
  ierr  = PCSetType(pc,PCMG);CHKERRQ(ierr);
  ierr  = PetscMalloc(nlevels*sizeof(MPI_Comm),&comms);CHKERRQ(ierr);
  for (i=0; i<nlevels; i++) {
    comms[i] = dmmg[i]->comm;
  }
  ierr  = PCMGSetLevels(pc,nlevels,comms);CHKERRQ(ierr);
  ierr  = PetscFree(comms);CHKERRQ(ierr); 
  ierr =  PCMGSetType(pc,PC_MG_FULL);CHKERRQ(ierr);

  ierr = PetscTypeCompare((PetscObject)pc,PCMG,&ismg);CHKERRQ(ierr);
  if (ismg) {
    /* set solvers for each level */
    for (i=0; i<nlevels; i++) {
      if (i < nlevels-1) { /* don't set for finest level, they are set in PCApply_MG()*/
	ierr = PCMGSetX(pc,i,dmmg[i]->x);CHKERRQ(ierr); 
	ierr = PCMGSetRhs(pc,i,dmmg[i]->b);CHKERRQ(ierr); 
      }
      if (i > 0) {
        ierr = PCMGSetR(pc,i,dmmg[i]->r);CHKERRQ(ierr); 
      }
      /* If using a matrix free multiply and did not provide an explicit matrix to build
         the preconditioner then must use no preconditioner 
      */
      ierr = PetscTypeCompare((PetscObject)dmmg[i]->B,MATSHELL,&isshell);CHKERRQ(ierr);
      ierr = PetscTypeCompare((PetscObject)dmmg[i]->B,MATDAAD,&ismf);CHKERRQ(ierr);
      ierr = PetscTypeCompare((PetscObject)dmmg[i]->B,MATMFFD,&ismffd);CHKERRQ(ierr);
      if (isshell || ismf || ismffd) {
        PC  lpc;
        ierr = PCMGGetSmoother(pc,i,&lksp);CHKERRQ(ierr); 
        ierr = KSPGetPC(lksp,&lpc);CHKERRQ(ierr);
        ierr = PCSetType(lpc,PCNONE);CHKERRQ(ierr);
      }
    }

    /* Set interpolation/restriction between levels */
    for (i=1; i<nlevels; i++) {
      ierr = PCMGSetInterpolation(pc,i,dmmg[i]->R);CHKERRQ(ierr); 
      ierr = PCMGSetRestriction(pc,i,dmmg[i]->R);CHKERRQ(ierr); 
    }
  }
  PetscFunctionReturn(0);
}
Esempio n. 2
0
File: ex5.c Progetto: fengyuqi/petsc
int main(int Argc,char **Args)
{
  PetscInt       x_mesh = 15,levels = 3,cycles = 1,use_jacobi = 0;
  PetscInt       i,smooths = 1,*N,its;
  PetscErrorCode ierr;
  PCMGType       am = PC_MG_MULTIPLICATIVE;
  Mat            cmat,mat[20],fmat;
  KSP            cksp,ksp[20],kspmg;
  PetscReal      e[3];  /* l_2 error,max error, residual */
  const char     *shellname;
  Vec            x,solution,X[20],R[20],B[20];
  PC             pcmg,pc;
  PetscBool      flg;

  PetscInitialize(&Argc,&Args,(char*)0,help);

  ierr = PetscOptionsGetInt(NULL,"-x",&x_mesh,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsGetInt(NULL,"-l",&levels,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsGetInt(NULL,"-c",&cycles,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsGetInt(NULL,"-smooths",&smooths,NULL);CHKERRQ(ierr);
  ierr = PetscOptionsHasName(NULL,"-a",&flg);CHKERRQ(ierr);

  if (flg) am = PC_MG_ADDITIVE;
  ierr = PetscOptionsHasName(NULL,"-f",&flg);CHKERRQ(ierr);
  if (flg) am = PC_MG_FULL;
  ierr = PetscOptionsHasName(NULL,"-j",&flg);CHKERRQ(ierr);
  if (flg) use_jacobi = 1;

  ierr = PetscMalloc1(levels,&N);CHKERRQ(ierr);
  N[0] = x_mesh;
  for (i=1; i<levels; i++) {
    N[i] = N[i-1]/2;
    if (N[i] < 1) SETERRQ(PETSC_COMM_WORLD,1,"Too many levels");
  }

  ierr = Create1dLaplacian(N[levels-1],&cmat);CHKERRQ(ierr);

  ierr = KSPCreate(PETSC_COMM_WORLD,&kspmg);CHKERRQ(ierr);
  ierr = KSPGetPC(kspmg,&pcmg);CHKERRQ(ierr);
  ierr = KSPSetFromOptions(kspmg);CHKERRQ(ierr);
  ierr = PCSetType(pcmg,PCMG);CHKERRQ(ierr);
  ierr = PCMGSetLevels(pcmg,levels,NULL);CHKERRQ(ierr);
  ierr = PCMGSetType(pcmg,am);CHKERRQ(ierr);

  ierr = PCMGGetCoarseSolve(pcmg,&cksp);CHKERRQ(ierr);
  ierr = KSPSetOperators(cksp,cmat,cmat);CHKERRQ(ierr);
  ierr = KSPGetPC(cksp,&pc);CHKERRQ(ierr);
  ierr = PCSetType(pc,PCLU);CHKERRQ(ierr);
  ierr = KSPSetType(cksp,KSPPREONLY);CHKERRQ(ierr);

  /* zero is finest level */
  for (i=0; i<levels-1; i++) {
    ierr = PCMGSetResidual(pcmg,levels - 1 - i,residual,(Mat)0);CHKERRQ(ierr);
    ierr = MatCreateShell(PETSC_COMM_WORLD,N[i+1],N[i],N[i+1],N[i],(void*)0,&mat[i]);CHKERRQ(ierr);
    ierr = MatShellSetOperation(mat[i],MATOP_MULT,(void (*)(void))restrct);CHKERRQ(ierr);
    ierr = MatShellSetOperation(mat[i],MATOP_MULT_TRANSPOSE_ADD,(void (*)(void))interpolate);CHKERRQ(ierr);
    ierr = PCMGSetInterpolation(pcmg,levels - 1 - i,mat[i]);CHKERRQ(ierr);
    ierr = PCMGSetRestriction(pcmg,levels - 1 - i,mat[i]);CHKERRQ(ierr);
    ierr = PCMGSetCyclesOnLevel(pcmg,levels - 1 - i,cycles);CHKERRQ(ierr);

    /* set smoother */
    ierr = PCMGGetSmoother(pcmg,levels - 1 - i,&ksp[i]);CHKERRQ(ierr);
    ierr = KSPGetPC(ksp[i],&pc);CHKERRQ(ierr);
    ierr = PCSetType(pc,PCSHELL);CHKERRQ(ierr);
    ierr = PCShellSetName(pc,"user_precond");CHKERRQ(ierr);
    ierr = PCShellGetName(pc,&shellname);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD,"level=%D, PCShell name is %s\n",i,shellname);CHKERRQ(ierr);

    /* this is a dummy! since KSP requires a matrix passed in  */
    ierr = KSPSetOperators(ksp[i],mat[i],mat[i]);CHKERRQ(ierr);
    /*
        We override the matrix passed in by forcing it to use Richardson with
        a user provided application. This is non-standard and this practice
        should be avoided.
    */
    ierr = PCShellSetApplyRichardson(pc,gauss_seidel);CHKERRQ(ierr);
    if (use_jacobi) {
      ierr = PCShellSetApplyRichardson(pc,jacobi);CHKERRQ(ierr);
    }
    ierr = KSPSetType(ksp[i],KSPRICHARDSON);CHKERRQ(ierr);
    ierr = KSPSetInitialGuessNonzero(ksp[i],PETSC_TRUE);CHKERRQ(ierr);
    ierr = KSPSetTolerances(ksp[i],PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,smooths);CHKERRQ(ierr);

    ierr = VecCreateSeq(PETSC_COMM_SELF,N[i],&x);CHKERRQ(ierr);

    X[levels - 1 - i] = x;
    if (i > 0) {
      ierr = PCMGSetX(pcmg,levels - 1 - i,x);CHKERRQ(ierr);
    }
    ierr = VecCreateSeq(PETSC_COMM_SELF,N[i],&x);CHKERRQ(ierr);

    B[levels -1 - i] = x;
    if (i > 0) {
      ierr = PCMGSetRhs(pcmg,levels - 1 - i,x);CHKERRQ(ierr);
    }
    ierr = VecCreateSeq(PETSC_COMM_SELF,N[i],&x);CHKERRQ(ierr);

    R[levels - 1 - i] = x;

    ierr = PCMGSetR(pcmg,levels - 1 - i,x);CHKERRQ(ierr);
  }
  /* create coarse level vectors */
  ierr = VecCreateSeq(PETSC_COMM_SELF,N[levels-1],&x);CHKERRQ(ierr);
  ierr = PCMGSetX(pcmg,0,x);CHKERRQ(ierr); X[0] = x;
  ierr = VecCreateSeq(PETSC_COMM_SELF,N[levels-1],&x);CHKERRQ(ierr);
  ierr = PCMGSetRhs(pcmg,0,x);CHKERRQ(ierr); B[0] = x;

  /* create matrix multiply for finest level */
  ierr = MatCreateShell(PETSC_COMM_WORLD,N[0],N[0],N[0],N[0],(void*)0,&fmat);CHKERRQ(ierr);
  ierr = MatShellSetOperation(fmat,MATOP_MULT,(void (*)(void))amult);CHKERRQ(ierr);
  ierr = KSPSetOperators(kspmg,fmat,fmat);CHKERRQ(ierr);

  ierr = CalculateSolution(N[0],&solution);CHKERRQ(ierr);
  ierr = CalculateRhs(B[levels-1]);CHKERRQ(ierr);
  ierr = VecSet(X[levels-1],0.0);CHKERRQ(ierr);

  ierr = residual((Mat)0,B[levels-1],X[levels-1],R[levels-1]);CHKERRQ(ierr);
  ierr = CalculateError(solution,X[levels-1],R[levels-1],e);CHKERRQ(ierr);
  ierr = PetscPrintf(PETSC_COMM_SELF,"l_2 error %g max error %g resi %g\n",(double)e[0],(double)e[1],(double)e[2]);CHKERRQ(ierr);

  ierr = KSPSolve(kspmg,B[levels-1],X[levels-1]);CHKERRQ(ierr);
  ierr = KSPGetIterationNumber(kspmg,&its);CHKERRQ(ierr);
  ierr = residual((Mat)0,B[levels-1],X[levels-1],R[levels-1]);CHKERRQ(ierr);
  ierr = CalculateError(solution,X[levels-1],R[levels-1],e);CHKERRQ(ierr);
  ierr = PetscPrintf(PETSC_COMM_SELF,"its %D l_2 error %g max error %g resi %g\n",its,(double)e[0],(double)e[1],(double)e[2]);CHKERRQ(ierr);

  ierr = PetscFree(N);CHKERRQ(ierr);
  ierr = VecDestroy(&solution);CHKERRQ(ierr);

  /* note we have to keep a list of all vectors allocated, this is
     not ideal, but putting it in MGDestroy is not so good either*/
  for (i=0; i<levels; i++) {
    ierr = VecDestroy(&X[i]);CHKERRQ(ierr);
    ierr = VecDestroy(&B[i]);CHKERRQ(ierr);
    if (i) {ierr = VecDestroy(&R[i]);CHKERRQ(ierr);}
  }
  for (i=0; i<levels-1; i++) {
    ierr = MatDestroy(&mat[i]);CHKERRQ(ierr);
  }
  ierr = MatDestroy(&cmat);CHKERRQ(ierr);
  ierr = MatDestroy(&fmat);CHKERRQ(ierr);
  ierr = KSPDestroy(&kspmg);CHKERRQ(ierr);
  ierr = PetscFinalize();
  return 0;
}
Esempio n. 3
0
File: mg.c Progetto: ziolai/petsc
PetscErrorCode PCSetUp_MG(PC pc)
{
  PC_MG          *mg        = (PC_MG*)pc->data;
  PC_MG_Levels   **mglevels = mg->levels;
  PetscErrorCode ierr;
  PetscInt       i,n = mglevels[0]->levels;
  PC             cpc;
  PetscBool      dump = PETSC_FALSE,opsset,use_amat,missinginterpolate = PETSC_FALSE;
  Mat            dA,dB;
  Vec            tvec;
  DM             *dms;
  PetscViewer    viewer = 0;

  PetscFunctionBegin;
  /* FIX: Move this to PCSetFromOptions_MG? */
  if (mg->usedmfornumberoflevels) {
    PetscInt levels;
    ierr = DMGetRefineLevel(pc->dm,&levels);CHKERRQ(ierr);
    levels++;
    if (levels > n) { /* the problem is now being solved on a finer grid */
      ierr     = PCMGSetLevels(pc,levels,NULL);CHKERRQ(ierr);
      n        = levels;
      ierr     = PCSetFromOptions(pc);CHKERRQ(ierr); /* it is bad to call this here, but otherwise will never be called for the new hierarchy */
      mglevels =  mg->levels;
    }
  }
  ierr = KSPGetPC(mglevels[0]->smoothd,&cpc);CHKERRQ(ierr);


  /* If user did not provide fine grid operators OR operator was not updated since last global KSPSetOperators() */
  /* so use those from global PC */
  /* Is this what we always want? What if user wants to keep old one? */
  ierr = KSPGetOperatorsSet(mglevels[n-1]->smoothd,NULL,&opsset);CHKERRQ(ierr);
  if (opsset) {
    Mat mmat;
    ierr = KSPGetOperators(mglevels[n-1]->smoothd,NULL,&mmat);CHKERRQ(ierr);
    if (mmat == pc->pmat) opsset = PETSC_FALSE;
  }

  if (!opsset) {
    ierr = PCGetUseAmat(pc,&use_amat);CHKERRQ(ierr);
    if(use_amat){
      ierr = PetscInfo(pc,"Using outer operators to define finest grid operator \n  because PCMGGetSmoother(pc,nlevels-1,&ksp);KSPSetOperators(ksp,...); was not called.\n");CHKERRQ(ierr);
      ierr = KSPSetOperators(mglevels[n-1]->smoothd,pc->mat,pc->pmat);CHKERRQ(ierr);
    }
    else {
      ierr = PetscInfo(pc,"Using matrix (pmat) operators to define finest grid operator \n  because PCMGGetSmoother(pc,nlevels-1,&ksp);KSPSetOperators(ksp,...); was not called.\n");CHKERRQ(ierr);
      ierr = KSPSetOperators(mglevels[n-1]->smoothd,pc->pmat,pc->pmat);CHKERRQ(ierr);
    }
  }

  for (i=n-1; i>0; i--) {
    if (!(mglevels[i]->interpolate || mglevels[i]->restrct)) {
      missinginterpolate = PETSC_TRUE;
      continue;
    }
  }
  /*
   Skipping if user has provided all interpolation/restriction needed (since DM might not be able to produce them (when coming from SNES/TS)
   Skipping for galerkin==2 (externally managed hierarchy such as ML and GAMG). Cleaner logic here would be great. Wrap ML/GAMG as DMs?
  */
  if (missinginterpolate && pc->dm && mg->galerkin != 2 && !pc->setupcalled) {
    /* construct the interpolation from the DMs */
    Mat p;
    Vec rscale;
    ierr     = PetscMalloc1(n,&dms);CHKERRQ(ierr);
    dms[n-1] = pc->dm;
    /* Separately create them so we do not get DMKSP interference between levels */
    for (i=n-2; i>-1; i--) {ierr = DMCoarsen(dms[i+1],MPI_COMM_NULL,&dms[i]);CHKERRQ(ierr);}
    for (i=n-2; i>-1; i--) {
      DMKSP     kdm;
      PetscBool dmhasrestrict;
      ierr = KSPSetDM(mglevels[i]->smoothd,dms[i]);CHKERRQ(ierr);
      if (mg->galerkin) {ierr = KSPSetDMActive(mglevels[i]->smoothd,PETSC_FALSE);CHKERRQ(ierr);}
      ierr = DMGetDMKSPWrite(dms[i],&kdm);CHKERRQ(ierr);
      /* Ugly hack so that the next KSPSetUp() will use the RHS that we set. A better fix is to change dmActive to take
       * a bitwise OR of computing the matrix, RHS, and initial iterate. */
      kdm->ops->computerhs = NULL;
      kdm->rhsctx          = NULL;
      if (!mglevels[i+1]->interpolate) {
        ierr = DMCreateInterpolation(dms[i],dms[i+1],&p,&rscale);CHKERRQ(ierr);
        ierr = PCMGSetInterpolation(pc,i+1,p);CHKERRQ(ierr);
        if (rscale) {ierr = PCMGSetRScale(pc,i+1,rscale);CHKERRQ(ierr);}
        ierr = VecDestroy(&rscale);CHKERRQ(ierr);
        ierr = MatDestroy(&p);CHKERRQ(ierr);
      }
      ierr = DMHasCreateRestriction(dms[i],&dmhasrestrict);CHKERRQ(ierr);
      if (dmhasrestrict && !mglevels[i+1]->restrct){
        ierr = DMCreateRestriction(dms[i],dms[i+1],&p);CHKERRQ(ierr);
        ierr = PCMGSetRestriction(pc,i+1,p);CHKERRQ(ierr);
        ierr = MatDestroy(&p);CHKERRQ(ierr);
      }
    }

    for (i=n-2; i>-1; i--) {ierr = DMDestroy(&dms[i]);CHKERRQ(ierr);}
    ierr = PetscFree(dms);CHKERRQ(ierr);
  }

  if (pc->dm && !pc->setupcalled) {
    /* finest smoother also gets DM but it is not active, independent of whether galerkin==2 */
    ierr = KSPSetDM(mglevels[n-1]->smoothd,pc->dm);CHKERRQ(ierr);
    ierr = KSPSetDMActive(mglevels[n-1]->smoothd,PETSC_FALSE);CHKERRQ(ierr);
  }

  if (mg->galerkin == 1) {
    Mat B;
    /* currently only handle case where mat and pmat are the same on coarser levels */
    ierr = KSPGetOperators(mglevels[n-1]->smoothd,&dA,&dB);CHKERRQ(ierr);
    if (!pc->setupcalled) {
      for (i=n-2; i>-1; i--) {
        if (!mglevels[i+1]->restrct && !mglevels[i+1]->interpolate) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_ARG_WRONGSTATE,"Must provide interpolation or restriction for each MG level except level 0");
        if (!mglevels[i+1]->interpolate) {
          ierr = PCMGSetInterpolation(pc,i+1,mglevels[i+1]->restrct);CHKERRQ(ierr);
        }
        if (!mglevels[i+1]->restrct) {
          ierr = PCMGSetRestriction(pc,i+1,mglevels[i+1]->interpolate);CHKERRQ(ierr);
        }
        if (mglevels[i+1]->interpolate == mglevels[i+1]->restrct) {
          ierr = MatPtAP(dB,mglevels[i+1]->interpolate,MAT_INITIAL_MATRIX,1.0,&B);CHKERRQ(ierr);
        } else {
          ierr = MatMatMatMult(mglevels[i+1]->restrct,dB,mglevels[i+1]->interpolate,MAT_INITIAL_MATRIX,1.0,&B);CHKERRQ(ierr);
        }
        ierr = KSPSetOperators(mglevels[i]->smoothd,B,B);CHKERRQ(ierr);
        if (i != n-2) {ierr = PetscObjectDereference((PetscObject)dB);CHKERRQ(ierr);}
        dB = B;
      }
      if (n > 1) {ierr = PetscObjectDereference((PetscObject)dB);CHKERRQ(ierr);}
    } else {
      for (i=n-2; i>-1; i--) {
        if (!mglevels[i+1]->restrct && !mglevels[i+1]->interpolate) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_ARG_WRONGSTATE,"Must provide interpolation or restriction for each MG level except level 0");
        if (!mglevels[i+1]->interpolate) {
          ierr = PCMGSetInterpolation(pc,i+1,mglevels[i+1]->restrct);CHKERRQ(ierr);
        }
        if (!mglevels[i+1]->restrct) {
          ierr = PCMGSetRestriction(pc,i+1,mglevels[i+1]->interpolate);CHKERRQ(ierr);
        }
        ierr = KSPGetOperators(mglevels[i]->smoothd,NULL,&B);CHKERRQ(ierr);
        if (mglevels[i+1]->interpolate == mglevels[i+1]->restrct) {
          ierr = MatPtAP(dB,mglevels[i+1]->interpolate,MAT_REUSE_MATRIX,1.0,&B);CHKERRQ(ierr);
        } else {
          ierr = MatMatMatMult(mglevels[i+1]->restrct,dB,mglevels[i+1]->interpolate,MAT_REUSE_MATRIX,1.0,&B);CHKERRQ(ierr);
        }
        ierr = KSPSetOperators(mglevels[i]->smoothd,B,B);CHKERRQ(ierr);
        dB   = B;
      }
    }
  } else if (!mg->galerkin && pc->dm && pc->dm->x) {
    /* need to restrict Jacobian location to coarser meshes for evaluation */
    for (i=n-2; i>-1; i--) {
      Mat R;
      Vec rscale;
      if (!mglevels[i]->smoothd->dm->x) {
        Vec *vecs;
        ierr = KSPCreateVecs(mglevels[i]->smoothd,1,&vecs,0,NULL);CHKERRQ(ierr);
        mglevels[i]->smoothd->dm->x = vecs[0];
        ierr = PetscFree(vecs);CHKERRQ(ierr);
      }
      ierr = PCMGGetRestriction(pc,i+1,&R);CHKERRQ(ierr);
      ierr = PCMGGetRScale(pc,i+1,&rscale);CHKERRQ(ierr);
      ierr = MatRestrict(R,mglevels[i+1]->smoothd->dm->x,mglevels[i]->smoothd->dm->x);CHKERRQ(ierr);
      ierr = VecPointwiseMult(mglevels[i]->smoothd->dm->x,mglevels[i]->smoothd->dm->x,rscale);CHKERRQ(ierr);
    }
  }
  if (!mg->galerkin && pc->dm) {
    for (i=n-2; i>=0; i--) {
      DM  dmfine,dmcoarse;
      Mat Restrict,Inject;
      Vec rscale;
      ierr   = KSPGetDM(mglevels[i+1]->smoothd,&dmfine);CHKERRQ(ierr);
      ierr   = KSPGetDM(mglevels[i]->smoothd,&dmcoarse);CHKERRQ(ierr);
      ierr   = PCMGGetRestriction(pc,i+1,&Restrict);CHKERRQ(ierr);
      ierr   = PCMGGetRScale(pc,i+1,&rscale);CHKERRQ(ierr);
      Inject = NULL;      /* Callback should create it if it needs Injection */
      ierr   = DMRestrict(dmfine,Restrict,rscale,Inject,dmcoarse);CHKERRQ(ierr);
    }
  }

  if (!pc->setupcalled) {
    for (i=0; i<n; i++) {
      ierr = KSPSetFromOptions(mglevels[i]->smoothd);CHKERRQ(ierr);
    }
    for (i=1; i<n; i++) {
      if (mglevels[i]->smoothu && (mglevels[i]->smoothu != mglevels[i]->smoothd)) {
        ierr = KSPSetFromOptions(mglevels[i]->smoothu);CHKERRQ(ierr);
      }
    }
    /* insure that if either interpolation or restriction is set the other other one is set */
    for (i=1; i<n; i++) {
      ierr = PCMGGetInterpolation(pc,i,NULL);CHKERRQ(ierr);
      ierr = PCMGGetRestriction(pc,i,NULL);CHKERRQ(ierr);
    }
    for (i=0; i<n-1; i++) {
      if (!mglevels[i]->b) {
        Vec *vec;
        ierr = KSPCreateVecs(mglevels[i]->smoothd,1,&vec,0,NULL);CHKERRQ(ierr);
        ierr = PCMGSetRhs(pc,i,*vec);CHKERRQ(ierr);
        ierr = VecDestroy(vec);CHKERRQ(ierr);
        ierr = PetscFree(vec);CHKERRQ(ierr);
      }
      if (!mglevels[i]->r && i) {
        ierr = VecDuplicate(mglevels[i]->b,&tvec);CHKERRQ(ierr);
        ierr = PCMGSetR(pc,i,tvec);CHKERRQ(ierr);
        ierr = VecDestroy(&tvec);CHKERRQ(ierr);
      }
      if (!mglevels[i]->x) {
        ierr = VecDuplicate(mglevels[i]->b,&tvec);CHKERRQ(ierr);
        ierr = PCMGSetX(pc,i,tvec);CHKERRQ(ierr);
        ierr = VecDestroy(&tvec);CHKERRQ(ierr);
      }
    }
    if (n != 1 && !mglevels[n-1]->r) {
      /* PCMGSetR() on the finest level if user did not supply it */
      Vec *vec;
      ierr = KSPCreateVecs(mglevels[n-1]->smoothd,1,&vec,0,NULL);CHKERRQ(ierr);
      ierr = PCMGSetR(pc,n-1,*vec);CHKERRQ(ierr);
      ierr = VecDestroy(vec);CHKERRQ(ierr);
      ierr = PetscFree(vec);CHKERRQ(ierr);
    }
  }

  if (pc->dm) {
    /* need to tell all the coarser levels to rebuild the matrix using the DM for that level */
    for (i=0; i<n-1; i++) {
      if (mglevels[i]->smoothd->setupstage != KSP_SETUP_NEW) mglevels[i]->smoothd->setupstage = KSP_SETUP_NEWMATRIX;
    }
  }

  for (i=1; i<n; i++) {
    if (mglevels[i]->smoothu == mglevels[i]->smoothd || mg->am == PC_MG_FULL || mg->am == PC_MG_KASKADE || mg->cyclesperpcapply > 1){
      /* if doing only down then initial guess is zero */
      ierr = KSPSetInitialGuessNonzero(mglevels[i]->smoothd,PETSC_TRUE);CHKERRQ(ierr);
    }
    if (mglevels[i]->eventsmoothsetup) {ierr = PetscLogEventBegin(mglevels[i]->eventsmoothsetup,0,0,0,0);CHKERRQ(ierr);}
    ierr = KSPSetUp(mglevels[i]->smoothd);CHKERRQ(ierr);
    if (mglevels[i]->smoothd->reason == KSP_DIVERGED_PCSETUP_FAILED) {
      pc->failedreason = PC_SUBPC_ERROR;
    }
    if (mglevels[i]->eventsmoothsetup) {ierr = PetscLogEventEnd(mglevels[i]->eventsmoothsetup,0,0,0,0);CHKERRQ(ierr);}
    if (!mglevels[i]->residual) {
      Mat mat;
      ierr = KSPGetOperators(mglevels[i]->smoothd,NULL,&mat);CHKERRQ(ierr);
      ierr = PCMGSetResidual(pc,i,PCMGResidualDefault,mat);CHKERRQ(ierr);
    }
  }
  for (i=1; i<n; i++) {
    if (mglevels[i]->smoothu && mglevels[i]->smoothu != mglevels[i]->smoothd) {
      Mat          downmat,downpmat;

      /* check if operators have been set for up, if not use down operators to set them */
      ierr = KSPGetOperatorsSet(mglevels[i]->smoothu,&opsset,NULL);CHKERRQ(ierr);
      if (!opsset) {
        ierr = KSPGetOperators(mglevels[i]->smoothd,&downmat,&downpmat);CHKERRQ(ierr);
        ierr = KSPSetOperators(mglevels[i]->smoothu,downmat,downpmat);CHKERRQ(ierr);
      }

      ierr = KSPSetInitialGuessNonzero(mglevels[i]->smoothu,PETSC_TRUE);CHKERRQ(ierr);
      if (mglevels[i]->eventsmoothsetup) {ierr = PetscLogEventBegin(mglevels[i]->eventsmoothsetup,0,0,0,0);CHKERRQ(ierr);}
      ierr = KSPSetUp(mglevels[i]->smoothu);CHKERRQ(ierr);
      if (mglevels[i]->smoothu->reason == KSP_DIVERGED_PCSETUP_FAILED) {
        pc->failedreason = PC_SUBPC_ERROR;
      }
      if (mglevels[i]->eventsmoothsetup) {ierr = PetscLogEventEnd(mglevels[i]->eventsmoothsetup,0,0,0,0);CHKERRQ(ierr);}
    }
  }

  if (mglevels[0]->eventsmoothsetup) {ierr = PetscLogEventBegin(mglevels[0]->eventsmoothsetup,0,0,0,0);CHKERRQ(ierr);}
  ierr = KSPSetUp(mglevels[0]->smoothd);CHKERRQ(ierr);
  if (mglevels[0]->smoothd->reason == KSP_DIVERGED_PCSETUP_FAILED) {
    pc->failedreason = PC_SUBPC_ERROR;
  }
  if (mglevels[0]->eventsmoothsetup) {ierr = PetscLogEventEnd(mglevels[0]->eventsmoothsetup,0,0,0,0);CHKERRQ(ierr);}

  /*
     Dump the interpolation/restriction matrices plus the
   Jacobian/stiffness on each level. This allows MATLAB users to
   easily check if the Galerkin condition A_c = R A_f R^T is satisfied.

   Only support one or the other at the same time.
  */
#if defined(PETSC_USE_SOCKET_VIEWER)
  ierr = PetscOptionsGetBool(((PetscObject)pc)->options,((PetscObject)pc)->prefix,"-pc_mg_dump_matlab",&dump,NULL);CHKERRQ(ierr);
  if (dump) viewer = PETSC_VIEWER_SOCKET_(PetscObjectComm((PetscObject)pc));
  dump = PETSC_FALSE;
#endif
  ierr = PetscOptionsGetBool(((PetscObject)pc)->options,((PetscObject)pc)->prefix,"-pc_mg_dump_binary",&dump,NULL);CHKERRQ(ierr);
  if (dump) viewer = PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)pc));

  if (viewer) {
    for (i=1; i<n; i++) {
      ierr = MatView(mglevels[i]->restrct,viewer);CHKERRQ(ierr);
    }
    for (i=0; i<n; i++) {
      ierr = KSPGetPC(mglevels[i]->smoothd,&pc);CHKERRQ(ierr);
      ierr = MatView(pc->mat,viewer);CHKERRQ(ierr);
    }
  }
  PetscFunctionReturn(0);
}
Esempio n. 4
0
File: ml.c Progetto: Kun-Qu/petsc
PetscErrorCode PCSetUp_ML(PC pc)
{
  PetscErrorCode  ierr;
  PetscMPIInt     size;
  FineGridCtx     *PetscMLdata;
  ML              *ml_object;
  ML_Aggregate    *agg_object;
  ML_Operator     *mlmat;
  PetscInt        nlocal_allcols,Nlevels,mllevel,level,level1,m,fine_level,bs;
  Mat             A,Aloc; 
  GridCtx         *gridctx; 
  PC_MG           *mg = (PC_MG*)pc->data;
  PC_ML           *pc_ml = (PC_ML*)mg->innerctx;
  PetscBool       isSeq, isMPI;
  KSP             smoother;
  PC              subpc;
  PetscInt        mesh_level, old_mesh_level;

  PetscFunctionBegin;
  A = pc->pmat;
  ierr = MPI_Comm_size(((PetscObject)A)->comm,&size);CHKERRQ(ierr);

  if (pc->setupcalled) {
    if (pc->flag == SAME_NONZERO_PATTERN && pc_ml->reuse_interpolation) {
      /*
       Reuse interpolaton instead of recomputing aggregates and updating the whole hierarchy. This is less expensive for
       multiple solves in which the matrix is not changing too quickly.
       */
      ml_object = pc_ml->ml_object;
      gridctx = pc_ml->gridctx;
      Nlevels = pc_ml->Nlevels;
      fine_level = Nlevels - 1;
      gridctx[fine_level].A = A;

      ierr = PetscObjectTypeCompare((PetscObject) A, MATSEQAIJ, &isSeq);CHKERRQ(ierr);
      ierr = PetscObjectTypeCompare((PetscObject) A, MATMPIAIJ, &isMPI);CHKERRQ(ierr);
      if (isMPI){
        ierr = MatConvert_MPIAIJ_ML(A,PETSC_NULL,MAT_INITIAL_MATRIX,&Aloc);CHKERRQ(ierr);
      } else if (isSeq) {
        Aloc = A;
        ierr = PetscObjectReference((PetscObject)Aloc);CHKERRQ(ierr);
      } else SETERRQ1(((PetscObject)pc)->comm,PETSC_ERR_ARG_WRONG, "Matrix type '%s' cannot be used with ML. ML can only handle AIJ matrices.",((PetscObject)A)->type_name);

      ierr = MatGetSize(Aloc,&m,&nlocal_allcols);CHKERRQ(ierr);
      PetscMLdata = pc_ml->PetscMLdata;
      ierr = MatDestroy(&PetscMLdata->Aloc);CHKERRQ(ierr);
      PetscMLdata->A    = A;
      PetscMLdata->Aloc = Aloc;
      ML_Init_Amatrix(ml_object,0,m,m,PetscMLdata);
      ML_Set_Amatrix_Matvec(ml_object,0,PetscML_matvec);

      mesh_level = ml_object->ML_finest_level;
      while (ml_object->SingleLevel[mesh_level].Rmat->to) {
        old_mesh_level = mesh_level;
        mesh_level = ml_object->SingleLevel[mesh_level].Rmat->to->levelnum;

        /* clean and regenerate A */
        mlmat = &(ml_object->Amat[mesh_level]);
        ML_Operator_Clean(mlmat);
        ML_Operator_Init(mlmat,ml_object->comm);
        ML_Gen_AmatrixRAP(ml_object, old_mesh_level, mesh_level);
      }

      level = fine_level - 1;
      if (size == 1) { /* convert ML P, R and A into seqaij format */
        for (mllevel=1; mllevel<Nlevels; mllevel++){
          mlmat = &(ml_object->Amat[mllevel]);
          ierr = MatWrapML_SeqAIJ(mlmat,MAT_REUSE_MATRIX,&gridctx[level].A);CHKERRQ(ierr);
          level--;
        }
      } else { /* convert ML P and R into shell format, ML A into mpiaij format */
        for (mllevel=1; mllevel<Nlevels; mllevel++){
          mlmat  = &(ml_object->Amat[mllevel]);
          ierr = MatWrapML_MPIAIJ(mlmat,MAT_REUSE_MATRIX,&gridctx[level].A);CHKERRQ(ierr);
          level--;
        }
      }

      for (level=0; level<fine_level; level++) {
        if (level > 0){
          ierr = PCMGSetResidual(pc,level,PCMGDefaultResidual,gridctx[level].A);CHKERRQ(ierr);
        }
        ierr = KSPSetOperators(gridctx[level].ksp,gridctx[level].A,gridctx[level].A,SAME_NONZERO_PATTERN);CHKERRQ(ierr);
      }
      ierr = PCMGSetResidual(pc,fine_level,PCMGDefaultResidual,gridctx[fine_level].A);CHKERRQ(ierr);
      ierr = KSPSetOperators(gridctx[fine_level].ksp,gridctx[level].A,gridctx[fine_level].A,SAME_NONZERO_PATTERN);CHKERRQ(ierr);

      ierr = PCSetUp_MG(pc);CHKERRQ(ierr);
      PetscFunctionReturn(0);
    } else {
      /* since ML can change the size of vectors/matrices at any level we must destroy everything */
      ierr = PCReset_ML(pc);CHKERRQ(ierr);
      ierr = PCReset_MG(pc);CHKERRQ(ierr);
    }
  }

  /* setup special features of PCML */
  /*--------------------------------*/
  /* covert A to Aloc to be used by ML at fine grid */
  pc_ml->size = size;
  ierr = PetscObjectTypeCompare((PetscObject) A, MATSEQAIJ, &isSeq);CHKERRQ(ierr);
  ierr = PetscObjectTypeCompare((PetscObject) A, MATMPIAIJ, &isMPI);CHKERRQ(ierr);
  if (isMPI){ 
    ierr = MatConvert_MPIAIJ_ML(A,PETSC_NULL,MAT_INITIAL_MATRIX,&Aloc);CHKERRQ(ierr);
  } else if (isSeq) {
    Aloc = A;
    ierr = PetscObjectReference((PetscObject)Aloc);CHKERRQ(ierr);
  } else SETERRQ1(((PetscObject)pc)->comm,PETSC_ERR_ARG_WRONG, "Matrix type '%s' cannot be used with ML. ML can only handle AIJ matrices.",((PetscObject)A)->type_name);

  /* create and initialize struct 'PetscMLdata' */
  ierr = PetscNewLog(pc,FineGridCtx,&PetscMLdata);CHKERRQ(ierr); 
  pc_ml->PetscMLdata = PetscMLdata;
  ierr = PetscMalloc((Aloc->cmap->n+1)*sizeof(PetscScalar),&PetscMLdata->pwork);CHKERRQ(ierr); 

  ierr = VecCreate(PETSC_COMM_SELF,&PetscMLdata->x);CHKERRQ(ierr);   
  ierr = VecSetSizes(PetscMLdata->x,Aloc->cmap->n,Aloc->cmap->n);CHKERRQ(ierr);
  ierr = VecSetType(PetscMLdata->x,VECSEQ);CHKERRQ(ierr); 

  ierr = VecCreate(PETSC_COMM_SELF,&PetscMLdata->y);CHKERRQ(ierr); 
  ierr = VecSetSizes(PetscMLdata->y,A->rmap->n,PETSC_DECIDE);CHKERRQ(ierr);
  ierr = VecSetType(PetscMLdata->y,VECSEQ);CHKERRQ(ierr);
  PetscMLdata->A    = A;
  PetscMLdata->Aloc = Aloc;
   
  /* create ML discretization matrix at fine grid */
  /* ML requires input of fine-grid matrix. It determines nlevels. */
  ierr = MatGetSize(Aloc,&m,&nlocal_allcols);CHKERRQ(ierr);
  ierr = MatGetBlockSize(A,&bs);CHKERRQ(ierr);
  ML_Create(&ml_object,pc_ml->MaxNlevels);
  ML_Comm_Set_UsrComm(ml_object->comm,((PetscObject)A)->comm);
  pc_ml->ml_object = ml_object;
  ML_Init_Amatrix(ml_object,0,m,m,PetscMLdata);
  ML_Set_Amatrix_Getrow(ml_object,0,PetscML_getrow,PetscML_comm,nlocal_allcols); 
  ML_Set_Amatrix_Matvec(ml_object,0,PetscML_matvec);

  ML_Set_Symmetrize(ml_object,pc_ml->Symmetrize ? ML_YES : ML_NO);

  /* aggregation */
  ML_Aggregate_Create(&agg_object); 
  pc_ml->agg_object = agg_object;

  {
    MatNullSpace mnull;
    ierr = MatGetNearNullSpace(A,&mnull);CHKERRQ(ierr);
    if (pc_ml->nulltype == PCML_NULLSPACE_AUTO) {
      if (mnull) pc_ml->nulltype = PCML_NULLSPACE_USER;
      else if (bs > 1) pc_ml->nulltype = PCML_NULLSPACE_BLOCK;
      else pc_ml->nulltype = PCML_NULLSPACE_SCALAR;
    }
    switch (pc_ml->nulltype) {
    case PCML_NULLSPACE_USER: {
      PetscScalar *nullvec;
      const PetscScalar *v;
      PetscBool has_const;
      PetscInt i,j,mlocal,nvec,M;
      const Vec *vecs;
      if (!mnull) SETERRQ(((PetscObject)pc)->comm,PETSC_ERR_USER,"Must provide explicit null space using MatSetNearNullSpace() to use user-specified null space");
      ierr = MatGetSize(A,&M,PETSC_NULL);CHKERRQ(ierr);
      ierr = MatGetLocalSize(Aloc,&mlocal,PETSC_NULL);CHKERRQ(ierr);
      ierr = MatNullSpaceGetVecs(mnull,&has_const,&nvec,&vecs);CHKERRQ(ierr);
      ierr = PetscMalloc((nvec+!!has_const)*mlocal*sizeof *nullvec,&nullvec);CHKERRQ(ierr);
      if (has_const) for (i=0; i<mlocal; i++) nullvec[i] = 1.0/M;
      for (i=0; i<nvec; i++) {
        ierr = VecGetArrayRead(vecs[i],&v);CHKERRQ(ierr);
        for (j=0; j<mlocal; j++) nullvec[(i+!!has_const)*mlocal + j] = v[j];
        ierr = VecRestoreArrayRead(vecs[i],&v);CHKERRQ(ierr);
      }
      ierr = ML_Aggregate_Set_NullSpace(agg_object,bs,nvec+!!has_const,nullvec,mlocal);CHKERRQ(ierr);
      ierr = PetscFree(nullvec);CHKERRQ(ierr);
    } break;
    case PCML_NULLSPACE_BLOCK:
      ierr = ML_Aggregate_Set_NullSpace(agg_object,bs,bs,0,0);CHKERRQ(ierr);
      break;
    case PCML_NULLSPACE_SCALAR:
      break;
    default: SETERRQ(((PetscObject)pc)->comm,PETSC_ERR_SUP,"Unknown null space type");
    }
  }
  ML_Aggregate_Set_MaxCoarseSize(agg_object,pc_ml->MaxCoarseSize);
  /* set options */
  switch (pc_ml->CoarsenScheme) { 
  case 1:  
    ML_Aggregate_Set_CoarsenScheme_Coupled(agg_object);break;
  case 2:
    ML_Aggregate_Set_CoarsenScheme_MIS(agg_object);break;
  case 3:
    ML_Aggregate_Set_CoarsenScheme_METIS(agg_object);break;
  }
  ML_Aggregate_Set_Threshold(agg_object,pc_ml->Threshold); 
  ML_Aggregate_Set_DampingFactor(agg_object,pc_ml->DampingFactor); 
  if (pc_ml->SpectralNormScheme_Anorm){
    ML_Set_SpectralNormScheme_Anorm(ml_object);
  }
  agg_object->keep_agg_information      = (int)pc_ml->KeepAggInfo;
  agg_object->keep_P_tentative          = (int)pc_ml->Reusable;
  agg_object->block_scaled_SA           = (int)pc_ml->BlockScaling;
  agg_object->minimizing_energy         = (int)pc_ml->EnergyMinimization;
  agg_object->minimizing_energy_droptol = (double)pc_ml->EnergyMinimizationDropTol;
  agg_object->cheap_minimizing_energy   = (int)pc_ml->EnergyMinimizationCheap;

  if (pc_ml->OldHierarchy) {
    Nlevels = ML_Gen_MGHierarchy_UsingAggregation(ml_object,0,ML_INCREASING,agg_object);
  } else {
    Nlevels = ML_Gen_MultiLevelHierarchy_UsingAggregation(ml_object,0,ML_INCREASING,agg_object);
  }
  if (Nlevels<=0) SETERRQ1(((PetscObject)pc)->comm,PETSC_ERR_ARG_OUTOFRANGE,"Nlevels %d must > 0",Nlevels);
  pc_ml->Nlevels = Nlevels;
  fine_level = Nlevels - 1;

  ierr = PCMGSetLevels(pc,Nlevels,PETSC_NULL);CHKERRQ(ierr); 
  /* set default smoothers */
  for (level=1; level<=fine_level; level++){
    if (size == 1){
      ierr = PCMGGetSmoother(pc,level,&smoother);CHKERRQ(ierr);
      ierr = KSPSetType(smoother,KSPRICHARDSON);CHKERRQ(ierr);
      ierr = KSPGetPC(smoother,&subpc);CHKERRQ(ierr);
      ierr = PCSetType(subpc,PCSOR);CHKERRQ(ierr);
    } else {
      ierr = PCMGGetSmoother(pc,level,&smoother);CHKERRQ(ierr);
      ierr = KSPSetType(smoother,KSPRICHARDSON);CHKERRQ(ierr);
      ierr = KSPGetPC(smoother,&subpc);CHKERRQ(ierr);
      ierr = PCSetType(subpc,PCSOR);CHKERRQ(ierr);
    }
  }
  ierr = PetscObjectOptionsBegin((PetscObject)pc);CHKERRQ(ierr);
  ierr = PCSetFromOptions_MG(pc);CHKERRQ(ierr); /* should be called in PCSetFromOptions_ML(), but cannot be called prior to PCMGSetLevels() */
  ierr = PetscOptionsEnd();CHKERRQ(ierr);

  ierr = PetscMalloc(Nlevels*sizeof(GridCtx),&gridctx);CHKERRQ(ierr);
  pc_ml->gridctx = gridctx;

  /* wrap ML matrices by PETSc shell matrices at coarsened grids.
     Level 0 is the finest grid for ML, but coarsest for PETSc! */
  gridctx[fine_level].A = A;

  level = fine_level - 1;
  if (size == 1){ /* convert ML P, R and A into seqaij format */
    for (mllevel=1; mllevel<Nlevels; mllevel++){ 
      mlmat = &(ml_object->Pmat[mllevel]);
      ierr  = MatWrapML_SeqAIJ(mlmat,MAT_INITIAL_MATRIX,&gridctx[level].P);CHKERRQ(ierr);
      mlmat = &(ml_object->Rmat[mllevel-1]);
      ierr  = MatWrapML_SeqAIJ(mlmat,MAT_INITIAL_MATRIX,&gridctx[level].R);CHKERRQ(ierr);
      
      mlmat = &(ml_object->Amat[mllevel]);
      ierr  = MatWrapML_SeqAIJ(mlmat,MAT_INITIAL_MATRIX,&gridctx[level].A);CHKERRQ(ierr);
      level--;
    }
  } else { /* convert ML P and R into shell format, ML A into mpiaij format */
    for (mllevel=1; mllevel<Nlevels; mllevel++){ 
      mlmat  = &(ml_object->Pmat[mllevel]);
      ierr = MatWrapML_SHELL(mlmat,MAT_INITIAL_MATRIX,&gridctx[level].P);CHKERRQ(ierr);
      mlmat  = &(ml_object->Rmat[mllevel-1]);
      ierr = MatWrapML_SHELL(mlmat,MAT_INITIAL_MATRIX,&gridctx[level].R);CHKERRQ(ierr);

      mlmat  = &(ml_object->Amat[mllevel]);
      ierr = MatWrapML_MPIAIJ(mlmat,MAT_INITIAL_MATRIX,&gridctx[level].A);CHKERRQ(ierr);  
      level--;
    }
  }

  /* create vectors and ksp at all levels */
  for (level=0; level<fine_level; level++){  
    level1 = level + 1;
    ierr = VecCreate(((PetscObject)gridctx[level].A)->comm,&gridctx[level].x);CHKERRQ(ierr); 
    ierr = VecSetSizes(gridctx[level].x,gridctx[level].A->cmap->n,PETSC_DECIDE);CHKERRQ(ierr);
    ierr = VecSetType(gridctx[level].x,VECMPI);CHKERRQ(ierr); 
    ierr = PCMGSetX(pc,level,gridctx[level].x);CHKERRQ(ierr); 
   
    ierr = VecCreate(((PetscObject)gridctx[level].A)->comm,&gridctx[level].b);CHKERRQ(ierr); 
    ierr = VecSetSizes(gridctx[level].b,gridctx[level].A->rmap->n,PETSC_DECIDE);CHKERRQ(ierr);
    ierr = VecSetType(gridctx[level].b,VECMPI);CHKERRQ(ierr); 
    ierr = PCMGSetRhs(pc,level,gridctx[level].b);CHKERRQ(ierr); 
    
    ierr = VecCreate(((PetscObject)gridctx[level1].A)->comm,&gridctx[level1].r);CHKERRQ(ierr); 
    ierr = VecSetSizes(gridctx[level1].r,gridctx[level1].A->rmap->n,PETSC_DECIDE);CHKERRQ(ierr);
    ierr = VecSetType(gridctx[level1].r,VECMPI);CHKERRQ(ierr); 
    ierr = PCMGSetR(pc,level1,gridctx[level1].r);CHKERRQ(ierr);

    if (level == 0){
      ierr = PCMGGetCoarseSolve(pc,&gridctx[level].ksp);CHKERRQ(ierr);
    } else {
      ierr = PCMGGetSmoother(pc,level,&gridctx[level].ksp);CHKERRQ(ierr);
    }  
  }
  ierr = PCMGGetSmoother(pc,fine_level,&gridctx[fine_level].ksp);CHKERRQ(ierr);

  /* create coarse level and the interpolation between the levels */
  for (level=0; level<fine_level; level++){  
    level1 = level + 1;
    ierr = PCMGSetInterpolation(pc,level1,gridctx[level].P);CHKERRQ(ierr);
    ierr = PCMGSetRestriction(pc,level1,gridctx[level].R);CHKERRQ(ierr);     
    if (level > 0){
      ierr = PCMGSetResidual(pc,level,PCMGDefaultResidual,gridctx[level].A);CHKERRQ(ierr);
    }    
    ierr = KSPSetOperators(gridctx[level].ksp,gridctx[level].A,gridctx[level].A,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);      
  }  
  ierr = PCMGSetResidual(pc,fine_level,PCMGDefaultResidual,gridctx[fine_level].A);CHKERRQ(ierr); 
  ierr = KSPSetOperators(gridctx[fine_level].ksp,gridctx[level].A,gridctx[fine_level].A,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);

  /* setupcalled is set to 0 so that MG is setup from scratch */
  pc->setupcalled = 0;  
  ierr = PCSetUp_MG(pc);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}
Esempio n. 5
0
PETSC_EXTERN void PETSC_STDCALL  pcmgsetr_(PC pc,PetscInt *l,Vec c, int *__ierr ){
*__ierr = PCMGSetR(
	(PC)PetscToPointer((pc) ),*l,
	(Vec)PetscToPointer((c) ));
}
void PETScMGSolver_UpdateWorkVectors( PETScMGSolver* self ) {
	PETScMGSolver_Level*	level;
	PC			pc;
	//unsigned		size;
	PetscInt		size, vecSize;
	PetscErrorCode		ec;
	unsigned		l_i;

	assert( self && Stg_CheckType( self, PETScMGSolver ) );

	if( self->nLevels == 1 )
		return;

	ec = KSPGetPC( self->mgData->ksp, &pc );
	CheckPETScError( ec );

	for( l_i = 0; l_i < self->nLevels; l_i++ ) {
		level = self->levels + l_i;

		//Matrix_GetLocalSize( level->A, &size, NULL );
		MatGetLocalSize( level->A, &size, PETSC_NULL );

                if( level->workRes )
                    VecGetLocalSize( level->workRes, &vecSize );

		if( l_i > 0 && (!level->workRes || /*Vector_GetLocalSize( level->workRes )*/vecSize != size) ) {
			if( level->workRes )
				Stg_VecDestroy(&level->workRes );
			//	FreeObject( level->workRes );
			//Vector_Duplicate( self->curSolution, (void**)&level->workRes );
			//Vector_SetLocalSize( level->workRes, size );
			//ec = PCMGSetR( pc, l_i, level->workRes->petscVec );
			VecCreate( MPI_COMM_WORLD, &level->workRes );
			VecSetSizes( level->workRes, size, PETSC_DECIDE );
			VecSetFromOptions( level->workRes );
#if( PETSC_VERSION_MAJOR <= 2 && PETSC_VERSION_MINOR >= 3 && PETSC_VERSION_SUBMINOR >= 3 )
			VecSetOption( level->workRes, VEC_IGNORE_NEGATIVE_INDICES );
#elif( PETSC_VERSION_MAJOR >= 3 )
			VecSetOption( level->workRes, VEC_IGNORE_NEGATIVE_INDICES, PETSC_TRUE );
#endif
			ec = PCMGSetR( pc, l_i, level->workRes );
			CheckPETScError( ec );
		}

		if( l_i < self->nLevels - 1 ) {
                    if( level->workSol )
			VecGetLocalSize( level->workSol, &vecSize );
                    if( !level->workSol || /*Vector_GetLocalSize( level->workSol )*/vecSize != size ) {
				if( level->workSol )
					Stg_VecDestroy(&level->workSol );
				//	FreeObject( level->workSol );
				//Vector_Duplicate( self->curSolution, (void**)&level->workSol );
				//Vector_SetLocalSize( level->workSol, size );
				//ec = PCMGSetX( pc, l_i, level->workSol->petscVec );
				VecCreate( MPI_COMM_WORLD, &level->workSol );
				VecSetSizes( level->workSol, size, PETSC_DECIDE );
				VecSetFromOptions( level->workSol );
#if( PETSC_VERSION_MAJOR <= 2 && PETSC_VERSION_MINOR >= 3 && PETSC_VERSION_SUBMINOR >= 3 )
				VecSetOption( level->workSol, VEC_IGNORE_NEGATIVE_INDICES );
#elif( PETSC_VERSION_MAJOR >= 3 )
				VecSetOption( level->workSol, VEC_IGNORE_NEGATIVE_INDICES, PETSC_TRUE );
#endif
				ec = PCMGSetX( pc, l_i, level->workSol );
				CheckPETScError( ec );
			}

                    if( level->workRHS )
			VecGetLocalSize( level->workRHS, &vecSize );
                    if( !level->workRHS || /*Vector_GetLocalSize( level->workRHS )*/vecSize != size ) {
				if( level->workRHS )
					Stg_VecDestroy(&level->workRHS );
				//	FreeObject( level->workRHS );
				//Vector_Duplicate( self->curSolution, (void**)&level->workRHS );
				//Vector_SetLocalSize( level->workRHS, size );
				//ec = PCMGSetRhs( pc, l_i, level->workRHS->petscVec );
				VecCreate( MPI_COMM_WORLD, &level->workRHS );
				VecSetSizes( level->workRHS, size, PETSC_DECIDE );
				VecSetFromOptions( level->workRHS );
#if( PETSC_VERSION_MAJOR <= 2 && PETSC_VERSION_MINOR >= 3 && PETSC_VERSION_SUBMINOR >= 3 )
				VecSetOption( level->workRHS, VEC_IGNORE_NEGATIVE_INDICES );
#elif( PETSC_VERSION_MAJOR >= 3 )
				VecSetOption( level->workRHS, VEC_IGNORE_NEGATIVE_INDICES, PETSC_TRUE );
#endif
				ec = PCMGSetRhs( pc, l_i, level->workRHS );
				CheckPETScError( ec );
			}
		}
	}
}