Ejemplo n.º 1
0
PetscErrorCode SNESNASMComputeFinalJacobian_Private(SNES snes, Vec Xfinal)
{
  Vec            X = Xfinal;
  SNES_NASM      *nasm = (SNES_NASM*)snes->data;
  SNES           subsnes;
  PetscInt       i,lag = 1;
  PetscErrorCode ierr;
  Vec            Xlloc,Xl,Fl,F;
  VecScatter     oscat,gscat;
  DM             dm,subdm;
  MatStructure   flg = DIFFERENT_NONZERO_PATTERN;
  PetscFunctionBegin;
  if (nasm->fjtype == 2) X = nasm->xinit;
  F = snes->vec_func;
  if (snes->normschedule == SNES_NORM_NONE) {ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);}
  ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr);
  ierr = SNESGetDM(snes,&dm);CHKERRQ(ierr);
  if (nasm->eventrestrictinterp) {ierr = PetscLogEventBegin(nasm->eventrestrictinterp,snes,0,0,0);CHKERRQ(ierr);}
  if (nasm->fjtype != 1) {
    for (i=0; i<nasm->n; i++) {
      Xlloc = nasm->xl[i];
      gscat = nasm->gscatter[i];
      oscat = nasm->oscatter[i];
      ierr = VecScatterBegin(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
    }
  }
  if (nasm->eventrestrictinterp) {ierr = PetscLogEventEnd(nasm->eventrestrictinterp,snes,0,0,0);CHKERRQ(ierr);}
  for (i=0; i<nasm->n; i++) {
    Fl      = nasm->subsnes[i]->vec_func;
    Xl      = nasm->x[i];
    Xlloc   = nasm->xl[i];
    subsnes = nasm->subsnes[i];
    oscat   = nasm->oscatter[i];
    gscat   = nasm->gscatter[i];
    if (nasm->fjtype != 1) {ierr = VecScatterEnd(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);}
    ierr = SNESGetDM(subsnes,&subdm);CHKERRQ(ierr);
    ierr = DMSubDomainRestrict(dm,oscat,gscat,subdm);CHKERRQ(ierr);
    if (nasm->fjtype != 1) {
      ierr = DMLocalToGlobalBegin(subdm,Xlloc,INSERT_VALUES,Xl);CHKERRQ(ierr);
      ierr = DMLocalToGlobalEnd(subdm,Xlloc,INSERT_VALUES,Xl);CHKERRQ(ierr);
    }
    if (subsnes->lagjacobian == -1)    subsnes->lagjacobian = -2;
    else if (subsnes->lagjacobian > 1) lag = subsnes->lagjacobian;
    ierr = SNESComputeFunction(subsnes,Xl,Fl);CHKERRQ(ierr);
    ierr = SNESComputeJacobian(subsnes,Xl,&subsnes->jacobian,&subsnes->jacobian_pre,&flg);CHKERRQ(ierr);
    if (lag > 1) subsnes->lagjacobian = lag;
    ierr = KSPSetOperators(subsnes->ksp,subsnes->jacobian,subsnes->jacobian_pre,flg);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}
Ejemplo n.º 2
0
PetscErrorCode SNESMonitorJacUpdateSpectrum(SNES snes,PetscInt it,PetscReal fnorm,void *ctx)
{
#if defined(PETSC_MISSING_LAPACK_GEEV)
  SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_SUP,"GEEV - Lapack routine is unavailable\nNot able to provide eigen values.");
#elif defined(PETSC_HAVE_ESSL)
  SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_SUP,"GEEV - No support for ESSL Lapack Routines");
#else
  Vec            X;
  Mat            J,dJ,dJdense;
  PetscErrorCode ierr;
  PetscErrorCode (*func)(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
  PetscInt       n,i;
  PetscBLASInt   nb,lwork;
  PetscReal      *eigr,*eigi;
  MatStructure   flg = DIFFERENT_NONZERO_PATTERN;
  PetscScalar    *work;
  PetscScalar    *a;

  PetscFunctionBegin;
  if (it == 0) PetscFunctionReturn(0);
  /* create the difference between the current update and the current jacobian */
  ierr = SNESGetSolution(snes,&X);CHKERRQ(ierr);
  ierr = SNESGetJacobian(snes,&J,NULL,&func,NULL);CHKERRQ(ierr);
  ierr = MatDuplicate(J,MAT_COPY_VALUES,&dJ);CHKERRQ(ierr);
  ierr = SNESComputeJacobian(snes,X,&dJ,&dJ,&flg);CHKERRQ(ierr);
  ierr = MatAXPY(dJ,-1.0,J,SAME_NONZERO_PATTERN);CHKERRQ(ierr);

  /* compute the spectrum directly */
  ierr  = MatConvert(dJ,MATSEQDENSE,MAT_INITIAL_MATRIX,&dJdense);CHKERRQ(ierr);
  ierr  = MatGetSize(dJ,&n,NULL);CHKERRQ(ierr);
  ierr  = PetscBLASIntCast(n,&nb);CHKERRQ(ierr);
  lwork = 3*nb;
  ierr  = PetscMalloc(n*sizeof(PetscReal),&eigr);CHKERRQ(ierr);
  ierr  = PetscMalloc(n*sizeof(PetscReal),&eigi);CHKERRQ(ierr);
  ierr  = PetscMalloc(lwork*sizeof(PetscScalar),&work);CHKERRQ(ierr);
  ierr  = MatDenseGetArray(dJdense,&a);CHKERRQ(ierr);
#if !defined(PETSC_USE_COMPLEX)
  {
    PetscBLASInt lierr;
    ierr = PetscFPTrapPush(PETSC_FP_TRAP_OFF);CHKERRQ(ierr);
    PetscStackCall("LAPACKgeev",LAPACKgeev_("N","N",&nb,a,&nb,eigr,eigi,NULL,&nb,NULL,&nb,work,&lwork,&lierr));
    if (lierr) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_LIB,"geev() error %d",lierr);
    ierr = PetscFPTrapPop();CHKERRQ(ierr);
  }
#else
  SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Not coded for complex");
#endif
  PetscPrintf(PetscObjectComm((PetscObject)snes),"Eigenvalues of J_%d - J_%d:\n",it,it-1);CHKERRQ(ierr);
  for (i=0;i<n;i++) {
    PetscPrintf(PetscObjectComm((PetscObject)snes),"%5d: %20.5g + %20.5gi\n",i,eigr[i],eigi[i]);CHKERRQ(ierr);
  }
  ierr = MatDenseRestoreArray(dJdense,&a);CHKERRQ(ierr);
  ierr = MatDestroy(&dJ);CHKERRQ(ierr);
  ierr = MatDestroy(&dJdense);CHKERRQ(ierr);
  ierr = PetscFree(eigr);CHKERRQ(ierr);
  ierr = PetscFree(eigi);CHKERRQ(ierr);
  ierr = PetscFree(work);CHKERRQ(ierr);
  PetscFunctionReturn(0);
#endif
}
Ejemplo n.º 3
0
static PetscErrorCode SNESSolve_KSPONLY(SNES snes)
{
  PetscErrorCode     ierr;
  PetscInt           lits;
  Vec                Y,X,F;

  PetscFunctionBegin;

  if (snes->xl || snes->xu || snes->ops->computevariablebounds) {
    SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE, "SNES solver %s does not support bounds", ((PetscObject)snes)->type_name);
  }

  snes->numFailures            = 0;
  snes->numLinearSolveFailures = 0;
  snes->reason                 = SNES_CONVERGED_ITERATING;
  snes->iter                   = 0;
  snes->norm                   = 0.0;

  X = snes->vec_sol;
  F = snes->vec_func;
  Y = snes->vec_sol_update;

  ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
  if (snes->numbermonitors) {
    PetscReal fnorm;
    ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr);
    ierr = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr);
  }

  /* Call general purpose update function */
  if (snes->ops->update) {
    ierr = (*snes->ops->update)(snes, 0);CHKERRQ(ierr);
  }

  /* Solve J Y = F, where J is Jacobian matrix */
  ierr = SNESComputeJacobian(snes,X,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
  ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
  ierr = KSPSolve(snes->ksp,F,Y);CHKERRQ(ierr);
  snes->reason = SNES_CONVERGED_ITS;
  SNESCheckKSPSolve(snes);

  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);
  snes->iter++;

  /* Take the computed step. */
  ierr = VecAXPY(X,-1.0,Y);CHKERRQ(ierr);
  if (snes->numbermonitors) {
    PetscReal fnorm;
    ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
    ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr);
    ierr = SNESMonitor(snes,1,fnorm);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}
Ejemplo n.º 4
0
PetscErrorCode SNESLineSearchApply_NCGLinear(SNESLineSearch linesearch)
{
    PetscScalar      alpha, ptAp;
    Vec              X, Y, F, W;
    SNES             snes;
    PetscErrorCode   ierr;
    PetscReal        *fnorm, *xnorm, *ynorm;
    MatStructure     flg = DIFFERENT_NONZERO_PATTERN;

    PetscFunctionBegin;

    ierr = SNESLineSearchGetSNES(linesearch, &snes);
    CHKERRQ(ierr);
    X = linesearch->vec_sol;
    W = linesearch->vec_sol_new;
    F = linesearch->vec_func;
    Y = linesearch->vec_update;
    fnorm = &linesearch->fnorm;
    xnorm = &linesearch->xnorm;
    ynorm = &linesearch->ynorm;

    /*

     The exact step size for unpreconditioned linear CG is just:
     alpha = (r, r) / (p, Ap) = (f, f) / (y, Jy)
     */
    ierr = SNESComputeJacobian(snes, X, &snes->jacobian, &snes->jacobian_pre, &flg);
    CHKERRQ(ierr);
    ierr = VecDot(F, F, &alpha);
    CHKERRQ(ierr);
    ierr = MatMult(snes->jacobian, Y, W);
    CHKERRQ(ierr);
    ierr = VecDot(Y, W, &ptAp);
    CHKERRQ(ierr);
    alpha = alpha / ptAp;
    ierr = PetscPrintf(((PetscObject)snes)->comm, "alpha: %G\n", PetscRealPart(alpha));
    CHKERRQ(ierr);
    ierr = VecAXPY(X, alpha, Y);
    CHKERRQ(ierr);
    ierr = SNESComputeFunction(snes, X, F);
    CHKERRQ(ierr);

    ierr = VecNorm(F, NORM_2, fnorm);
    CHKERRQ(ierr);
    ierr = VecNorm(X, NORM_2, xnorm);
    CHKERRQ(ierr);
    ierr = VecNorm(Y, NORM_2, ynorm);
    CHKERRQ(ierr);
    PetscFunctionReturn(0);
}
Ejemplo n.º 5
0
PetscErrorCode SNESLineSearchApply_NCGLinear(SNESLineSearch linesearch)
{
  PetscScalar    alpha, ptAp;
  Vec            X, Y, F, W;
  SNES           snes;
  PetscErrorCode ierr;
  PetscReal      *fnorm, *xnorm, *ynorm;

  PetscFunctionBegin;
  ierr  = SNESLineSearchGetSNES(linesearch, &snes);CHKERRQ(ierr);
  X     = linesearch->vec_sol;
  W     = linesearch->vec_sol_new;
  F     = linesearch->vec_func;
  Y     = linesearch->vec_update;
  fnorm = &linesearch->fnorm;
  xnorm = &linesearch->xnorm;
  ynorm = &linesearch->ynorm;

  if (!snes->jacobian) {
    ierr = SNESSetUpMatrices(snes);CHKERRQ(ierr);
  }

  /*

   The exact step size for unpreconditioned linear CG is just:
   alpha = (r, r) / (p, Ap) = (f, f) / (y, Jy)
   */
  ierr  = SNESComputeJacobian(snes, X, snes->jacobian, snes->jacobian_pre);CHKERRQ(ierr);
  ierr  = VecDot(F, F, &alpha);CHKERRQ(ierr);
  ierr  = MatMult(snes->jacobian, Y, W);CHKERRQ(ierr);
  ierr  = VecDot(Y, W, &ptAp);CHKERRQ(ierr);
  alpha = alpha / ptAp;
  ierr  = VecAXPY(X,-alpha,Y);CHKERRQ(ierr);
  ierr  = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);

  ierr = VecNorm(F,NORM_2,fnorm);CHKERRQ(ierr);
  ierr = VecNorm(X,NORM_2,xnorm);CHKERRQ(ierr);
  ierr = VecNorm(Y,NORM_2,ynorm);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}
Ejemplo n.º 6
0
Archivo: ms.c Proyecto: Kun-Qu/petsc
static PetscErrorCode SNESSolve_MS(SNES snes)
{
  SNES_MS        *ms = (SNES_MS*)snes->data;
  Vec            X = snes->vec_sol,F = snes->vec_func;
  PetscReal      fnorm;
  MatStructure   mstruct;
  PetscInt       i;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  snes->reason = SNES_CONVERGED_ITERATING;
  ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
  snes->iter = 0;
  snes->norm = 0.;
  ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
  if (!snes->vec_func_init_set) {
    ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
    if (snes->domainerror) {
      snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
      PetscFunctionReturn(0);
    }
  } else {
    snes->vec_func_init_set = PETSC_FALSE;
  }
  if (snes->jacobian) {         /* This method does not require a Jacobian, but it is usually preconditioned by PBJacobi */
    ierr = SNESComputeJacobian(snes,snes->vec_sol,&snes->jacobian,&snes->jacobian_pre,&mstruct);CHKERRQ(ierr);
    ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre,mstruct);CHKERRQ(ierr);
  }
  if (ms->norms) {
    if (!snes->norm_init_set) {
      ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr); /* fnorm <- ||F||  */
      if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
    } else {
      fnorm = snes->norm_init;
      snes->norm_init_set = PETSC_FALSE;
    }
    /* Monitor convergence */
    ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
    snes->iter = 0;
    snes->norm = fnorm;
    ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
    SNESLogConvHistory(snes,snes->norm,0);
    ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);

    /* set parameter for default relative tolerance convergence test */
    snes->ttol = fnorm*snes->rtol;
    /* Test for convergence */
    ierr = (*snes->ops->converged)(snes,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
    if (snes->reason) PetscFunctionReturn(0);
  }

  /* Call general purpose update function */
  if (snes->ops->update) {
    ierr = (*snes->ops->update)(snes,snes->iter);CHKERRQ(ierr);
  }
  for (i = 0; i < snes->max_its; i++) {
    ierr = SNESMSStep_3Sstar(snes,X,F);CHKERRQ(ierr);

    if (i+1 < snes->max_its || ms->norms) {
      ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
      if (snes->domainerror) {
        snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
        PetscFunctionReturn(0);
      }
    }

    if (ms->norms) {
      ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr); /* fnorm <- ||F||  */
      if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
      /* Monitor convergence */
      ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
      snes->iter = i+1;
      snes->norm = fnorm;
      ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
      SNESLogConvHistory(snes,snes->norm,0);
      ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);

      /* Test for convergence */
      ierr = (*snes->ops->converged)(snes,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
      if (snes->reason) PetscFunctionReturn(0);
    }

    /* Call general purpose update function */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }
  }
  if (!snes->reason) snes->reason = SNES_CONVERGED_ITS;
  PetscFunctionReturn(0);
}
Ejemplo n.º 7
0
int main(int argc, char **argv)
{
  SNES           snes;                 /* nonlinear solver */
  DM             dm;                   /* problem definition */
  Vec            u,r;                  /* solution, residual vectors */
  Mat            A,J;                  /* Jacobian matrix */
  MatNullSpace   nullSpace;            /* May be necessary for pressure */
  AppCtx         user;                 /* user-defined work context */
  JacActionCtx   userJ;                /* context for Jacobian MF action */
  PetscInt       its;                  /* iterations for convergence */
  PetscReal      error         = 0.0;  /* L_2 error in the solution */
  PetscInt       numComponents = 0, f;
  PetscErrorCode ierr;

  ierr = PetscInitialize(&argc, &argv, NULL, help);CHKERRQ(ierr);
  ierr = ProcessOptions(PETSC_COMM_WORLD, &user);CHKERRQ(ierr);
  ierr = SNESCreate(PETSC_COMM_WORLD, &snes);CHKERRQ(ierr);
  ierr = CreateMesh(PETSC_COMM_WORLD, &user, &dm);CHKERRQ(ierr);
  ierr = SNESSetDM(snes, dm);CHKERRQ(ierr);

  ierr = SetupElement(dm, &user);CHKERRQ(ierr);
  for (f = 0; f < NUM_FIELDS; ++f) {
    PetscInt numComp;
    ierr = PetscFEGetNumComponents(user.fe[f], &numComp);CHKERRQ(ierr);
    numComponents += numComp;
  }
  ierr = PetscMalloc(NUM_FIELDS * sizeof(void (*)(const PetscReal[], PetscScalar *)), &user.exactFuncs);CHKERRQ(ierr);
  user.fem.bcFuncs = (void (**)(const PetscReal[], PetscScalar *)) user.exactFuncs;
  ierr = SetupExactSolution(dm, &user);CHKERRQ(ierr);
  ierr = SetupSection(dm, &user);CHKERRQ(ierr);
  ierr = DMPlexCreateClosureIndex(dm, NULL);CHKERRQ(ierr);

  ierr = DMCreateGlobalVector(dm, &u);CHKERRQ(ierr);
  ierr = VecDuplicate(u, &r);CHKERRQ(ierr);

  ierr = DMSetMatType(dm,MATAIJ);CHKERRQ(ierr);
  ierr = DMCreateMatrix(dm, &J);CHKERRQ(ierr);
  if (user.jacobianMF) {
    PetscInt M, m, N, n;

    ierr = MatGetSize(J, &M, &N);CHKERRQ(ierr);
    ierr = MatGetLocalSize(J, &m, &n);CHKERRQ(ierr);
    ierr = MatCreate(PETSC_COMM_WORLD, &A);CHKERRQ(ierr);
    ierr = MatSetSizes(A, m, n, M, N);CHKERRQ(ierr);
    ierr = MatSetType(A, MATSHELL);CHKERRQ(ierr);
    ierr = MatSetUp(A);CHKERRQ(ierr);
    ierr = MatShellSetOperation(A, MATOP_MULT, (void (*)(void))FormJacobianAction);CHKERRQ(ierr);

    userJ.dm   = dm;
    userJ.J    = J;
    userJ.user = &user;

    ierr = DMCreateLocalVector(dm, &userJ.u);CHKERRQ(ierr);
    ierr = DMPlexProjectFunctionLocal(dm, user.fe, user.exactFuncs, INSERT_BC_VALUES, userJ.u);CHKERRQ(ierr);
    ierr = MatShellSetContext(A, &userJ);CHKERRQ(ierr);
  } else {
    A = J;
  }
  ierr = CreatePressureNullSpace(dm, &user, &nullSpace);CHKERRQ(ierr);
  ierr = MatSetNullSpace(J, nullSpace);CHKERRQ(ierr);
  if (A != J) {
    ierr = MatSetNullSpace(A, nullSpace);CHKERRQ(ierr);
  }

  ierr = DMSNESSetFunctionLocal(dm,  (PetscErrorCode (*)(DM,Vec,Vec,void*))DMPlexComputeResidualFEM,&user);CHKERRQ(ierr);
  ierr = DMSNESSetJacobianLocal(dm,  (PetscErrorCode (*)(DM,Vec,Mat,Mat,MatStructure*,void*))DMPlexComputeJacobianFEM,&user);CHKERRQ(ierr);
  ierr = SNESSetJacobian(snes, A, J, NULL, NULL);CHKERRQ(ierr);

  ierr = SNESSetFromOptions(snes);CHKERRQ(ierr);

  ierr = DMPlexProjectFunction(dm, user.fe, user.exactFuncs, INSERT_ALL_VALUES, u);CHKERRQ(ierr);
  if (user.showInitial) {ierr = DMVecViewLocal(dm, u, PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);}
  if (user.runType == RUN_FULL) {
    ierr = DMPlexProjectFunction(dm, user.fe, user.initialGuess, INSERT_VALUES, u);CHKERRQ(ierr);
    if (user.showInitial) {ierr = DMVecViewLocal(dm, u, PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);}
    if (user.debug) {
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr);
      ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    }
    ierr = SNESSolve(snes, NULL, u);CHKERRQ(ierr);
    ierr = SNESGetIterationNumber(snes, &its);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Number of SNES iterations = %D\n", its);CHKERRQ(ierr);
    ierr = DMPlexComputeL2Diff(dm, user.fe, user.exactFuncs, u, &error);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %.3g\n", error);CHKERRQ(ierr);
    if (user.showSolution) {
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Solution\n");CHKERRQ(ierr);
      ierr = VecChop(u, 3.0e-9);CHKERRQ(ierr);
      ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    }
  } else {
    PetscReal res = 0.0;

    /* Check discretization error */
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr);
    ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    ierr = DMPlexComputeL2Diff(dm, user.fe, user.exactFuncs, u, &error);CHKERRQ(ierr);
    if (error >= 1.0e-11) {
      ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %g\n", error);CHKERRQ(ierr);
    } else {
      ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: < 1.0e-11\n", error);CHKERRQ(ierr);
    }
    /* Check residual */
    ierr = SNESComputeFunction(snes, u, r);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial Residual\n");CHKERRQ(ierr);
    ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr);
    ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Residual: %g\n", res);CHKERRQ(ierr);
    /* Check Jacobian */
    {
      Vec          b;
      MatStructure flag;
      PetscBool    isNull;

      ierr = SNESComputeJacobian(snes, u, &A, &A, &flag);CHKERRQ(ierr);
      ierr = MatNullSpaceTest(nullSpace, J, &isNull);CHKERRQ(ierr);
      if (!isNull) SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_PLIB, "The null space calculated for the system operator is invalid.");
      ierr = VecDuplicate(u, &b);CHKERRQ(ierr);
      ierr = VecSet(r, 0.0);CHKERRQ(ierr);
      ierr = SNESComputeFunction(snes, r, b);CHKERRQ(ierr);
      ierr = MatMult(A, u, r);CHKERRQ(ierr);
      ierr = VecAXPY(r, 1.0, b);CHKERRQ(ierr);
      ierr = VecDestroy(&b);CHKERRQ(ierr);
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Au - b = Au + F(0)\n");CHKERRQ(ierr);
      ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr);
      ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
      ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr);
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Linear L_2 Residual: %g\n", res);CHKERRQ(ierr);
    }
  }

  if (user.runType == RUN_FULL) {
    PetscViewer viewer;
    Vec         uLocal;
    const char *name;

    ierr = PetscViewerCreate(PETSC_COMM_WORLD, &viewer);CHKERRQ(ierr);
    ierr = PetscViewerSetType(viewer, PETSCVIEWERVTK);CHKERRQ(ierr);
    ierr = PetscViewerSetFormat(viewer, PETSC_VIEWER_ASCII_VTK);CHKERRQ(ierr);
    ierr = PetscViewerFileSetName(viewer, "ex62_sol.vtk");CHKERRQ(ierr);

    ierr = DMGetLocalVector(dm, &uLocal);CHKERRQ(ierr);
    ierr = PetscObjectGetName((PetscObject) u, &name);CHKERRQ(ierr);
    ierr = PetscObjectSetName((PetscObject) uLocal, name);CHKERRQ(ierr);
    ierr = DMGlobalToLocalBegin(dm, u, INSERT_VALUES, uLocal);CHKERRQ(ierr);
    ierr = DMGlobalToLocalEnd(dm, u, INSERT_VALUES, uLocal);CHKERRQ(ierr);
    ierr = VecView(uLocal, viewer);CHKERRQ(ierr);
    ierr = DMRestoreLocalVector(dm, &uLocal);CHKERRQ(ierr);

    ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
  }

  ierr = PetscFree(user.exactFuncs);CHKERRQ(ierr);
  ierr = DestroyElement(&user);CHKERRQ(ierr);
  ierr = MatNullSpaceDestroy(&nullSpace);CHKERRQ(ierr);
  if (user.jacobianMF) {
    ierr = VecDestroy(&userJ.u);CHKERRQ(ierr);
  }
  if (A != J) {
    ierr = MatDestroy(&A);CHKERRQ(ierr);
  }
  ierr = MatDestroy(&J);CHKERRQ(ierr);
  ierr = VecDestroy(&u);CHKERRQ(ierr);
  ierr = VecDestroy(&r);CHKERRQ(ierr);
  ierr = SNESDestroy(&snes);CHKERRQ(ierr);
  ierr = DMDestroy(&dm);CHKERRQ(ierr);
  ierr = PetscFinalize();
  return 0;
}
Ejemplo n.º 8
0
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);
}
Ejemplo n.º 9
0
int main(int argc, char **argv)
{
  DM             dm;          /* Problem specification */
  DM             dmAux;       /* Material specification */
  SNES           snes;        /* nonlinear solver */
  Vec            u,r;         /* solution, residual vectors */
  Mat            A,J;         /* Jacobian matrix */
  MatNullSpace   nullSpace;   /* May be necessary for Neumann conditions */
  AppCtx         user;        /* user-defined work context */
  JacActionCtx   userJ;       /* context for Jacobian MF action */
  PetscInt       its;         /* iterations for convergence */
  PetscReal      error = 0.0; /* L_2 error in the solution */
  PetscInt       numComponents;
  PetscErrorCode ierr;

  ierr = PetscInitialize(&argc, &argv, NULL, help);CHKERRQ(ierr);
  ierr = ProcessOptions(PETSC_COMM_WORLD, &user);CHKERRQ(ierr);
  ierr = SNESCreate(PETSC_COMM_WORLD, &snes);CHKERRQ(ierr);
  ierr = CreateMesh(PETSC_COMM_WORLD, &user, &dm);CHKERRQ(ierr);
  ierr = SNESSetDM(snes, dm);CHKERRQ(ierr);
  ierr = DMSetApplicationContext(dm, &user);CHKERRQ(ierr);

  user.fem.fe = user.fe;
  ierr = PetscFECreateDefault(dm, user.dim, 1, PETSC_TRUE, NULL, -1, &user.fe[0]);CHKERRQ(ierr);
  if (user.bcType != NEUMANN) {
    user.fem.feBd = NULL; user.feBd[0] = NULL;
  } else {
    user.fem.feBd = user.feBd;
    ierr = PetscFECreateDefault(dm, user.dim-1, 1, PETSC_TRUE, "bd_", -1, &user.feBd[0]);CHKERRQ(ierr);
  }
  ierr = PetscFEGetNumComponents(user.fe[0], &numComponents);CHKERRQ(ierr);
  ierr = PetscMalloc(NUM_FIELDS * sizeof(void (*)(const PetscReal[], PetscScalar *, void *)), &user.exactFuncs);CHKERRQ(ierr);
  ierr = SetupProblem(dm, &user);CHKERRQ(ierr);
  ierr = SetupSection(dm, &user);CHKERRQ(ierr);
  /* Setup Material */
  ierr = DMClone(dm, &dmAux);CHKERRQ(ierr);
  ierr = DMPlexCopyCoordinates(dm, dmAux);CHKERRQ(ierr);
  if (user.variableCoefficient != COEFF_FIELD) {
    user.fem.feAux = NULL; user.feAux[0] = NULL;
  } else {
    PetscQuadrature q;

    user.fem.feAux = user.feAux;
    ierr = PetscFECreateDefault(dmAux, user.dim, 1, PETSC_TRUE, "mat_", -1, &user.feAux[0]);CHKERRQ(ierr);
    ierr = PetscFEGetQuadrature(user.fe[0], &q);CHKERRQ(ierr);
    ierr = PetscFESetQuadrature(user.feAux[0], q);CHKERRQ(ierr);
  }
  ierr = SetupMaterialSection(dmAux, &user);CHKERRQ(ierr);
  ierr = SetupMaterial(dm, dmAux, &user);CHKERRQ(ierr);
  ierr = DMDestroy(&dmAux);CHKERRQ(ierr);

  ierr = DMCreateGlobalVector(dm, &u);CHKERRQ(ierr);
  ierr = PetscObjectSetName((PetscObject) u, "potential");CHKERRQ(ierr);
  ierr = VecDuplicate(u, &r);CHKERRQ(ierr);

  ierr = DMSetMatType(dm,MATAIJ);CHKERRQ(ierr);
  ierr = DMCreateMatrix(dm, &J);CHKERRQ(ierr);
  if (user.jacobianMF) {
    PetscInt M, m, N, n;

    ierr = MatGetSize(J, &M, &N);CHKERRQ(ierr);
    ierr = MatGetLocalSize(J, &m, &n);CHKERRQ(ierr);
    ierr = MatCreate(PETSC_COMM_WORLD, &A);CHKERRQ(ierr);
    ierr = MatSetSizes(A, m, n, M, N);CHKERRQ(ierr);
    ierr = MatSetType(A, MATSHELL);CHKERRQ(ierr);
    ierr = MatSetUp(A);CHKERRQ(ierr);
#if 0
    ierr = MatShellSetOperation(A, MATOP_MULT, (void (*)(void))FormJacobianAction);CHKERRQ(ierr);
#endif

    userJ.dm   = dm;
    userJ.J    = J;
    userJ.user = &user;

    ierr = DMCreateLocalVector(dm, &userJ.u);CHKERRQ(ierr);
    ierr = DMPlexProjectFunctionLocal(dm, user.fe, user.exactFuncs, NULL, INSERT_BC_VALUES, userJ.u);CHKERRQ(ierr);
    ierr = MatShellSetContext(A, &userJ);CHKERRQ(ierr);
  } else {
    A = J;
  }
  if (user.bcType == NEUMANN) {
    ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject) dm), PETSC_TRUE, 0, NULL, &nullSpace);CHKERRQ(ierr);
    ierr = MatSetNullSpace(J, nullSpace);CHKERRQ(ierr);
    if (A != J) {
      ierr = MatSetNullSpace(A, nullSpace);CHKERRQ(ierr);
    }
  }

  ierr = DMSNESSetFunctionLocal(dm,  (PetscErrorCode (*)(DM,Vec,Vec,void*)) DMPlexComputeResidualFEM, &user);CHKERRQ(ierr);
  ierr = DMSNESSetJacobianLocal(dm,  (PetscErrorCode (*)(DM,Vec,Mat,Mat,void*)) DMPlexComputeJacobianFEM, &user);CHKERRQ(ierr);
  ierr = SNESSetJacobian(snes, A, J, NULL, NULL);CHKERRQ(ierr);

  ierr = SNESSetFromOptions(snes);CHKERRQ(ierr);

  ierr = DMPlexProjectFunction(dm, user.fe, user.exactFuncs, NULL, INSERT_ALL_VALUES, u);CHKERRQ(ierr);
  if (user.checkpoint) {
#if defined(PETSC_HAVE_HDF5)
    ierr = PetscViewerHDF5PushGroup(user.checkpoint, "/fields");CHKERRQ(ierr);
    ierr = VecLoad(u, user.checkpoint);CHKERRQ(ierr);
    ierr = PetscViewerHDF5PopGroup(user.checkpoint);CHKERRQ(ierr);
#endif
  }
  ierr = PetscViewerDestroy(&user.checkpoint);CHKERRQ(ierr);
  if (user.showInitial) {
    Vec lv;
    ierr = DMGetLocalVector(dm, &lv);CHKERRQ(ierr);
    ierr = DMGlobalToLocalBegin(dm, u, INSERT_VALUES, lv);CHKERRQ(ierr);
    ierr = DMGlobalToLocalEnd(dm, u, INSERT_VALUES, lv);CHKERRQ(ierr);
    ierr = DMPrintLocalVec(dm, "Local function", 1.0e-10, lv);CHKERRQ(ierr);
    ierr = DMRestoreLocalVector(dm, &lv);CHKERRQ(ierr);
  }
  if (user.runType == RUN_FULL) {
    void (*initialGuess[numComponents])(const PetscReal x[], PetscScalar *, void *ctx);
    PetscInt c;

    for (c = 0; c < numComponents; ++c) initialGuess[c] = zero;
    ierr = DMPlexProjectFunction(dm, user.fe, initialGuess, NULL, INSERT_VALUES, u);CHKERRQ(ierr);
    if (user.debug) {
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr);
      ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    }
    ierr = SNESSolve(snes, NULL, u);CHKERRQ(ierr);
    ierr = SNESGetIterationNumber(snes, &its);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Number of SNES iterations = %D\n", its);CHKERRQ(ierr);
    ierr = DMPlexComputeL2Diff(dm, user.fe, user.exactFuncs, NULL, u, &error);CHKERRQ(ierr);
    if (error < 1.0e-11) {ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: < 1.0e-11\n");CHKERRQ(ierr);}
    else                 {ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %g\n", error);CHKERRQ(ierr);}
    if (user.showSolution) {
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Solution\n");CHKERRQ(ierr);
      ierr = VecChop(u, 3.0e-9);CHKERRQ(ierr);
      ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    }
  } else if (user.runType == RUN_PERF) {
    PetscReal res = 0.0;

    ierr = SNESComputeFunction(snes, u, r);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial Residual\n");CHKERRQ(ierr);
    ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr);
    ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Residual: %g\n", res);CHKERRQ(ierr);
  } else {
    PetscReal res = 0.0;

    /* Check discretization error */
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr);
    ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    ierr = DMPlexComputeL2Diff(dm, user.fe, user.exactFuncs, NULL, u, &error);CHKERRQ(ierr);
    if (error < 1.0e-11) {ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: < 1.0e-11\n");CHKERRQ(ierr);}
    else                 {ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %g\n", error);CHKERRQ(ierr);}
    /* Check residual */
    ierr = SNESComputeFunction(snes, u, r);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial Residual\n");CHKERRQ(ierr);
    ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr);
    ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Residual: %g\n", res);CHKERRQ(ierr);
    /* Check Jacobian */
    {
      Vec          b;

      ierr = SNESComputeJacobian(snes, u, A, A);CHKERRQ(ierr);
      ierr = VecDuplicate(u, &b);CHKERRQ(ierr);
      ierr = VecSet(r, 0.0);CHKERRQ(ierr);
      ierr = SNESComputeFunction(snes, r, b);CHKERRQ(ierr);
      ierr = MatMult(A, u, r);CHKERRQ(ierr);
      ierr = VecAXPY(r, 1.0, b);CHKERRQ(ierr);
      ierr = VecDestroy(&b);CHKERRQ(ierr);
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Au - b = Au + F(0)\n");CHKERRQ(ierr);
      ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr);
      ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
      ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr);
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Linear L_2 Residual: %g\n", res);CHKERRQ(ierr);
    }
  }
  ierr = VecViewFromOptions(u, NULL, "-vec_view");CHKERRQ(ierr);

  if (user.bcType == NEUMANN) {
    ierr = MatNullSpaceDestroy(&nullSpace);CHKERRQ(ierr);
  }
  if (user.jacobianMF) {
    ierr = VecDestroy(&userJ.u);CHKERRQ(ierr);
  }
  if (A != J) {ierr = MatDestroy(&A);CHKERRQ(ierr);}
  ierr = PetscFEDestroy(&user.fe[0]);CHKERRQ(ierr);
  ierr = PetscFEDestroy(&user.feBd[0]);CHKERRQ(ierr);
  ierr = PetscFEDestroy(&user.feAux[0]);CHKERRQ(ierr);
  ierr = MatDestroy(&J);CHKERRQ(ierr);
  ierr = VecDestroy(&u);CHKERRQ(ierr);
  ierr = VecDestroy(&r);CHKERRQ(ierr);
  ierr = SNESDestroy(&snes);CHKERRQ(ierr);
  ierr = DMDestroy(&dm);CHKERRQ(ierr);
  ierr = PetscFree(user.exactFuncs);CHKERRQ(ierr);
  ierr = PetscFinalize();
  return 0;
}
Ejemplo n.º 10
0
PetscErrorCode JacMatMultCompare(SNES snes,Vec x,Vec p,double hopt)
{
  Vec            yy1, yy2; /* work vectors */
  PetscViewer    view2;    /* viewer */
  Mat            J;        /* analytic Jacobian (set as preconditioner matrix) */
  Mat            Jmf;      /* matrix-free Jacobian (set as true system matrix) */
  double         h;        /* differencing parameter */
  Vec            f;
  PetscScalar    alpha;
  PetscReal      yy1n,yy2n,enorm;
  PetscErrorCode ierr;
  PetscInt       i;
  PetscBool      printv = PETSC_FALSE;
  char           filename[32];
  MPI_Comm       comm;

  PetscFunctionBegin;
  ierr = PetscObjectGetComm((PetscObject)snes,&comm);CHKERRQ(ierr);
  /* Compute function and analytic Jacobian at x */
  ierr = SNESGetJacobian(snes,&Jmf,&J,NULL,NULL);CHKERRQ(ierr);
  ierr = SNESComputeJacobian(snes,x,Jmf,J);CHKERRQ(ierr);
  ierr = SNESGetFunction(snes,&f,NULL,NULL);CHKERRQ(ierr);
  ierr = SNESComputeFunction(snes,x,f);CHKERRQ(ierr);

  /* Duplicate work vectors */
  ierr = VecDuplicate(x,&yy2);CHKERRQ(ierr);
  ierr = VecDuplicate(x,&yy1);CHKERRQ(ierr);

  /* Compute true matrix-vector product */
  ierr = MatMult(J,p,yy1);CHKERRQ(ierr);
  ierr = VecNorm(yy1,NORM_2,&yy1n);CHKERRQ(ierr);

  /* View product vector if desired */
  ierr = PetscOptionsGetBool(NULL,"-print_vecs",&printv,NULL);CHKERRQ(ierr);
  if (printv) {
    ierr = PetscViewerASCIIOpen(comm,"y1.out",&view2);CHKERRQ(ierr);
    ierr = PetscViewerSetFormat(view2,PETSC_VIEWER_ASCII_COMMON);CHKERRQ(ierr);
    ierr = VecView(yy1,view2);CHKERRQ(ierr);
    ierr = PetscViewerDestroy(&view2);CHKERRQ(ierr);
  }

  /* Test Jacobian-vector product computation */
  alpha = -1.0;
  h     = 0.01 * hopt;
  for (i=0; i<5; i++) {
    /* Set differencing parameter for matrix-free multiplication */
    ierr = SNESDefaultMatrixFreeSetParameters2(Jmf,PETSC_DEFAULT,PETSC_DEFAULT,h);CHKERRQ(ierr);

    /* Compute matrix-vector product via differencing approximation */
    ierr = MatMult(Jmf,p,yy2);CHKERRQ(ierr);
    ierr = VecNorm(yy2,NORM_2,&yy2n);CHKERRQ(ierr);

    /* View product vector if desired */
    if (printv) {
      sprintf(filename,"y2.%d.out",(int)i);
      ierr = PetscViewerASCIIOpen(comm,filename,&view2);CHKERRQ(ierr);
      ierr = PetscViewerSetFormat(view2,PETSC_VIEWER_ASCII_COMMON);CHKERRQ(ierr);
      ierr = VecView(yy2,view2);CHKERRQ(ierr);
      ierr = PetscViewerDestroy(&view2);CHKERRQ(ierr);
    }

    /* Compute relative error */
    ierr  = VecAXPY(yy2,alpha,yy1);CHKERRQ(ierr);
    ierr  = VecNorm(yy2,NORM_2,&enorm);CHKERRQ(ierr);
    enorm = enorm/yy1n;
    ierr  = PetscFPrintf(comm,stdout,"h = %g: relative error = %g\n",(double)h,(double)enorm);CHKERRQ(ierr);
    h    *= 10.0;
  }
  PetscFunctionReturn(0);
}
Ejemplo n.º 11
0
/*
   SNESSolve_NEWTONTR - Implements Newton's Method with a very simple trust
   region approach for solving systems of nonlinear equations.


*/
static PetscErrorCode SNESSolve_NEWTONTR(SNES snes)
{
  SNES_NEWTONTR       *neP = (SNES_NEWTONTR*)snes->data;
  Vec                 X,F,Y,G,Ytmp;
  PetscErrorCode      ierr;
  PetscInt            maxits,i,lits;
  PetscReal           rho,fnorm,gnorm,gpnorm,xnorm=0,delta,nrm,ynorm,norm1;
  PetscScalar         cnorm;
  KSP                 ksp;
  SNESConvergedReason reason = SNES_CONVERGED_ITERATING;
  PetscBool           conv   = PETSC_FALSE,breakout = PETSC_FALSE;

  PetscFunctionBegin;
  if (snes->xl || snes->xu || snes->ops->computevariablebounds) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE, "SNES solver %s does not support bounds", ((PetscObject)snes)->type_name);

  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 */
  G      = snes->work[1];
  Ytmp   = snes->work[2];

  ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->iter = 0;
  ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);

  if (!snes->vec_func_init_set) {
    ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);          /* F(X) */
  } else snes->vec_func_init_set = PETSC_FALSE;

  ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr);             /* fnorm <- || F || */
  SNESCheckFunctionNorm(snes,fnorm);
  ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr);             /* fnorm <- || F || */
  ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->norm = fnorm;
  ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
  delta      = xnorm ? neP->delta0*xnorm : neP->delta0;
  neP->delta = delta;
  ierr       = SNESLogConvergenceHistory(snes,fnorm,0);CHKERRQ(ierr);
  ierr       = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr);

  /* test convergence */
  ierr = (*snes->ops->converged)(snes,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
  if (snes->reason) PetscFunctionReturn(0);

  /* Set the stopping criteria to use the More' trick. */
  ierr = PetscOptionsGetBool(((PetscObject)snes)->options,((PetscObject)snes)->prefix,"-snes_tr_ksp_regular_convergence_test",&conv,NULL);CHKERRQ(ierr);
  if (!conv) {
    SNES_TR_KSPConverged_Ctx *ctx;
    ierr      = SNESGetKSP(snes,&ksp);CHKERRQ(ierr);
    ierr      = PetscNew(&ctx);CHKERRQ(ierr);
    ctx->snes = snes;
    ierr      = KSPConvergedDefaultCreate(&ctx->ctx);CHKERRQ(ierr);
    ierr      = KSPSetConvergenceTest(ksp,SNESTR_KSPConverged_Private,ctx,SNESTR_KSPConverged_Destroy);CHKERRQ(ierr);
    ierr      = PetscInfo(snes,"Using Krylov convergence test SNESTR_KSPConverged_Private\n");CHKERRQ(ierr);
  }

  for (i=0; i<maxits; i++) {

    /* Call general purpose update function */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }

    /* Solve J Y = F, where J is Jacobian matrix */
    ierr = SNESComputeJacobian(snes,X,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
    SNESCheckJacobianDomainerror(snes);
    ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
    ierr = KSPSolve(snes->ksp,F,Ytmp);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);
    ierr  = VecNorm(Ytmp,NORM_2,&nrm);CHKERRQ(ierr);
    norm1 = nrm;
    while (1) {
      ierr = VecCopy(Ytmp,Y);CHKERRQ(ierr);
      nrm  = norm1;

      /* Scale Y if need be and predict new value of F norm */
      if (nrm >= delta) {
        nrm    = delta/nrm;
        gpnorm = (1.0 - nrm)*fnorm;
        cnorm  = nrm;
        ierr   = PetscInfo1(snes,"Scaling direction by %g\n",(double)nrm);CHKERRQ(ierr);
        ierr   = VecScale(Y,cnorm);CHKERRQ(ierr);
        nrm    = gpnorm;
        ynorm  = delta;
      } else {
        gpnorm = 0.0;
        ierr   = PetscInfo(snes,"Direction is in Trust Region\n");CHKERRQ(ierr);
        ynorm  = nrm;
      }
      ierr = VecAYPX(Y,-1.0,X);CHKERRQ(ierr);            /* Y <- X - Y */
      ierr = VecCopy(X,snes->vec_sol_update);CHKERRQ(ierr);
      ierr = SNESComputeFunction(snes,Y,G);CHKERRQ(ierr); /*  F(X) */
      ierr = VecNorm(G,NORM_2,&gnorm);CHKERRQ(ierr);      /* gnorm <- || g || */
      if (fnorm == gpnorm) rho = 0.0;
      else rho = (fnorm*fnorm - gnorm*gnorm)/(fnorm*fnorm - gpnorm*gpnorm);

      /* Update size of trust region */
      if      (rho < neP->mu)  delta *= neP->delta1;
      else if (rho < neP->eta) delta *= neP->delta2;
      else                     delta *= neP->delta3;
      ierr = PetscInfo3(snes,"fnorm=%g, gnorm=%g, ynorm=%g\n",(double)fnorm,(double)gnorm,(double)ynorm);CHKERRQ(ierr);
      ierr = PetscInfo3(snes,"gpred=%g, rho=%g, delta=%g\n",(double)gpnorm,(double)rho,(double)delta);CHKERRQ(ierr);

      neP->delta = delta;
      if (rho > neP->sigma) break;
      ierr = PetscInfo(snes,"Trying again in smaller region\n");CHKERRQ(ierr);
      /* check to see if progress is hopeless */
      neP->itflag = PETSC_FALSE;
      ierr        = SNESTR_Converged_Private(snes,snes->iter,xnorm,ynorm,fnorm,&reason,snes->cnvP);CHKERRQ(ierr);
      if (!reason) { ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&reason,snes->cnvP);CHKERRQ(ierr); }
      if (reason) {
        /* We're not progressing, so return with the current iterate */
        ierr     = SNESMonitor(snes,i+1,fnorm);CHKERRQ(ierr);
        breakout = PETSC_TRUE;
        break;
      }
      snes->numFailures++;
    }
    if (!breakout) {
      /* Update function and solution vectors */
      fnorm = gnorm;
      ierr  = VecCopy(G,F);CHKERRQ(ierr);
      ierr  = VecCopy(Y,X);CHKERRQ(ierr);
      /* Monitor convergence */
      ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
      snes->iter = i+1;
      snes->norm = fnorm;
      snes->xnorm = xnorm;
      snes->ynorm = ynorm;
      ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
      ierr       = SNESLogConvergenceHistory(snes,snes->norm,lits);CHKERRQ(ierr);
      ierr       = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);
      /* Test for convergence, xnorm = || X || */
      neP->itflag = PETSC_TRUE;
      if (snes->ops->converged != SNESConvergedSkip) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); }
      ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&reason,snes->cnvP);CHKERRQ(ierr);
      if (reason) break;
    } else break;
  }
  if (i == maxits) {
    ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr);
    if (!reason) reason = SNES_DIVERGED_MAX_IT;
  }
  ierr         = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->reason = reason;
  ierr         = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}
Ejemplo n.º 12
0
PetscErrorCode TSMonitorSPEig(TS ts,PetscInt step,PetscReal ptime,Vec v,void *monctx)
{
  TSMonitorSPEigCtx ctx = (TSMonitorSPEigCtx) monctx;
  PetscErrorCode    ierr;
  KSP               ksp = ctx->ksp;
  PetscInt          n,N,nits,neig,i,its = 200;
  PetscReal         *r,*c,time_step_save;
  PetscDrawSP       drawsp = ctx->drawsp;
  Mat               A,B;
  Vec               xdot;
  SNES              snes;

  PetscFunctionBegin;
  if (!step) PetscFunctionReturn(0);
  if (((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason)) {
    ierr = VecDuplicate(v,&xdot);CHKERRQ(ierr);
    ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
    ierr = SNESGetJacobian(snes,&A,&B,NULL,NULL);CHKERRQ(ierr);
    ierr = MatDuplicate(A,MAT_DO_NOT_COPY_VALUES,&B);CHKERRQ(ierr);
    /*
       This doesn't work because methods keep and use internal information about the shift so it
       seems we would need code for each method to trick the correct Jacobian in being computed.
     */
    time_step_save = ts->time_step;
    ts->time_step  = PETSC_MAX_REAL;

    ierr = SNESComputeJacobian(snes,v,A,B);CHKERRQ(ierr);

    ts->time_step  = time_step_save;

    ierr = KSPSetOperators(ksp,B,B);CHKERRQ(ierr);
    ierr = VecGetSize(v,&n);CHKERRQ(ierr);
    if (n < 200) its = n;
    ierr = KSPSetTolerances(ksp,1.e-10,PETSC_DEFAULT,PETSC_DEFAULT,its);CHKERRQ(ierr);
    ierr = VecSetRandom(xdot,ctx->rand);CHKERRQ(ierr);
    ierr = KSPSolve(ksp,xdot,xdot);CHKERRQ(ierr);
    ierr = VecDestroy(&xdot);CHKERRQ(ierr);
    ierr = KSPGetIterationNumber(ksp,&nits);CHKERRQ(ierr);
    N    = nits+2;

    if (nits) {
      PetscDraw     draw;
      PetscReal     pause;
      PetscDrawAxis axis;
      PetscReal     xmin,xmax,ymin,ymax;

      ierr = PetscDrawSPReset(drawsp);CHKERRQ(ierr);
      ierr = PetscDrawSPSetLimits(drawsp,ctx->xmin,ctx->xmax,ctx->ymin,ctx->ymax);CHKERRQ(ierr);
      ierr = PetscMalloc2(PetscMax(n,N),&r,PetscMax(n,N),&c);CHKERRQ(ierr);
      if (ctx->computeexplicitly) {
        ierr = KSPComputeEigenvaluesExplicitly(ksp,n,r,c);CHKERRQ(ierr);
        neig = n;
      } else {
        ierr = KSPComputeEigenvalues(ksp,N,r,c,&neig);CHKERRQ(ierr);
      }
      /* We used the positive operator to be able to reuse KSPs that require positive definiteness, now flip the spectrum as is conventional for ODEs */
      for (i=0; i<neig; i++) r[i] = -r[i];
      for (i=0; i<neig; i++) {
        if (ts->ops->linearstability) {
          PetscReal fr,fi;
          ierr = TSComputeLinearStability(ts,r[i],c[i],&fr,&fi);CHKERRQ(ierr);
          if ((fr*fr + fi*fi) > 1.0) {
            ierr = PetscPrintf(ctx->comm,"Linearized Eigenvalue %g + %g i linear stability function %g norm indicates unstable scheme \n",(double)r[i],(double)c[i],(double)(fr*fr + fi*fi));CHKERRQ(ierr);
          }
        }
        ierr = PetscDrawSPAddPoint(drawsp,r+i,c+i);CHKERRQ(ierr);
      }
      ierr = PetscFree2(r,c);CHKERRQ(ierr);
      ierr = PetscDrawSPGetDraw(drawsp,&draw);CHKERRQ(ierr);
      ierr = PetscDrawGetPause(draw,&pause);CHKERRQ(ierr);
      ierr = PetscDrawSetPause(draw,0.0);CHKERRQ(ierr);
      ierr = PetscDrawSPDraw(drawsp,PETSC_TRUE);CHKERRQ(ierr);
      ierr = PetscDrawSetPause(draw,pause);CHKERRQ(ierr);

      if (ts->ops->linearstability) {
        ierr = PetscDrawSPGetAxis(drawsp,&axis);CHKERRQ(ierr);
        ierr = PetscDrawAxisGetLimits(axis,&xmin,&xmax,&ymin,&ymax);CHKERRQ(ierr);
        ierr = PetscDrawIndicatorFunction(draw,xmin,xmax,ymin,ymax,PETSC_DRAW_CYAN,(PetscErrorCode (*)(void*,PetscReal,PetscReal,PetscBool*))TSLinearStabilityIndicator,ts);CHKERRQ(ierr);
        ierr = PetscDrawSPDraw(drawsp,PETSC_FALSE);CHKERRQ(ierr);
      }
    }
    ierr = MatDestroy(&B);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}
Ejemplo n.º 13
0
static PetscErrorCode SNESSolve_QN(SNES snes)
{
  PetscErrorCode      ierr;
  SNES_QN             *qn = (SNES_QN*) snes->data;
  Vec                 X,Xold;
  Vec                 F,B;
  Vec                 Y,FPC,D,Dold;
  SNESConvergedReason reason;
  PetscInt            i, i_r;
  PetscReal           fnorm,xnorm,ynorm,gnorm;
  PetscBool           lssucceed,powell,periodic;
  PetscScalar         DolddotD,DolddotDold,DdotD,YdotD;
  MatStructure        flg = DIFFERENT_NONZERO_PATTERN;

  /* basically just a regular newton's method except for the application of the jacobian */
  PetscFunctionBegin;

  F             = snes->vec_func;       /* residual vector */
  Y             = snes->vec_sol_update; /* search direction generated by J^-1D*/
  B             = snes->vec_rhs;

  X             = snes->vec_sol;        /* solution vector */
  Xold          = snes->work[0];

  /* directions generated by the preconditioned problem with F_pre = F or x - M(x, b) */
  D             = snes->work[1];
  Dold          = snes->work[2];

  snes->reason = SNES_CONVERGED_ITERATING;

  ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
  snes->iter = 0;
  snes->norm = 0.;
  ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
  if (!snes->vec_func_init_set){
    ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
    if (snes->domainerror) {
      snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
      PetscFunctionReturn(0);
    }
  } else {
    snes->vec_func_init_set = PETSC_FALSE;
  }

  if (!snes->norm_init_set) {
    ierr = VecNorm(F, NORM_2, &fnorm);CHKERRQ(ierr); /* fnorm <- ||F||  */
    if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
  } else {
    fnorm = snes->norm_init;
    snes->norm_init_set = PETSC_FALSE;
  }

  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);

  /* composed solve */
  if (snes->pc && snes->pcside == PC_RIGHT) {
    ierr = SNESSetInitialFunction(snes->pc, F);CHKERRQ(ierr);
    ierr = SNESSetInitialFunctionNorm(snes->pc, fnorm);CHKERRQ(ierr);
    ierr = SNESSolve(snes->pc, B, X);CHKERRQ(ierr);
    ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
    if (reason < 0 && (reason != SNES_DIVERGED_MAX_IT)) {
      snes->reason = SNES_DIVERGED_INNER;
      PetscFunctionReturn(0);
    }
    ierr = SNESGetFunction(snes->pc, &FPC, PETSC_NULL, PETSC_NULL);CHKERRQ(ierr);
    ierr = VecCopy(FPC, F);CHKERRQ(ierr);
    ierr = SNESGetFunctionNorm(snes->pc, &fnorm);CHKERRQ(ierr);
    ierr = VecCopy(F, Y);CHKERRQ(ierr);
  } else {
    ierr = VecCopy(F, Y);CHKERRQ(ierr);
  }
  ierr = VecCopy(Y, D);CHKERRQ(ierr);

  /* scale the initial update */
  if (qn->scale_type == SNES_QN_SCALE_JACOBIAN) {
    ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr);
  }

  for (i = 0, i_r = 0; i < snes->max_its; i++, i_r++) {
    switch(qn->type) {
    case SNES_QN_BADBROYDEN:
      ierr = SNESQNApply_BadBroyden(snes,i_r,Y,X,Xold,D,Dold);CHKERRQ(ierr);
      break;
    case SNES_QN_BROYDEN:
      ierr = SNESQNApply_Broyden(snes,i_r,Y,X,Xold,D,Dold);CHKERRQ(ierr);
      break;
    case SNES_QN_LBFGS:
      SNESQNApply_LBFGS(snes,i_r,Y,X,Xold,D,Dold);CHKERRQ(ierr);
      break;
    }
    /* line search for lambda */
    ynorm = 1; gnorm = fnorm;
    ierr = VecCopy(D, Dold);CHKERRQ(ierr);
    ierr = VecCopy(X, Xold);CHKERRQ(ierr);
    ierr = SNESLineSearchApply(snes->linesearch, X, F, &fnorm, Y);CHKERRQ(ierr);
    if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break;
    if (snes->domainerror) {
      snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
      PetscFunctionReturn(0);
      }
    ierr = SNESLineSearchGetSuccess(snes->linesearch, &lssucceed);CHKERRQ(ierr);
    if (!lssucceed) {
      if (++snes->numFailures >= snes->maxFailures) {
        snes->reason = SNES_DIVERGED_LINE_SEARCH;
        break;
      }
    }
    ierr = SNESLineSearchGetNorms(snes->linesearch, &xnorm, &fnorm, &ynorm);CHKERRQ(ierr);
    if (qn->scale_type == SNES_QN_SCALE_LINESEARCH) {
      ierr = SNESLineSearchGetLambda(snes->linesearch, &qn->scaling);CHKERRQ(ierr);
    }

    /* convergence monitoring */
    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);

    ierr = SNESSetIterationNumber(snes, i+1);CHKERRQ(ierr);
    ierr = SNESSetFunctionNorm(snes, fnorm);CHKERRQ(ierr);

    SNESLogConvHistory(snes,snes->norm,snes->iter);
    ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);
    /* set parameter for default relative tolerance convergence test */
    ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
    if (snes->reason) PetscFunctionReturn(0);

    if (snes->pc && snes->pcside == PC_RIGHT) {
      ierr = SNESSetInitialFunction(snes->pc, F);CHKERRQ(ierr);
      ierr = SNESSetInitialFunctionNorm(snes->pc, fnorm);CHKERRQ(ierr);
      ierr = SNESSolve(snes->pc, B, X);CHKERRQ(ierr);
      ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
      if (reason < 0 && (reason != SNES_DIVERGED_MAX_IT)) {
        snes->reason = SNES_DIVERGED_INNER;
        PetscFunctionReturn(0);
      }
      ierr = SNESGetFunction(snes->pc, &FPC, PETSC_NULL, PETSC_NULL);CHKERRQ(ierr);
      ierr = VecCopy(FPC, F);CHKERRQ(ierr);
      ierr = SNESGetFunctionNorm(snes->pc, &fnorm);CHKERRQ(ierr);
      ierr = VecCopy(F, D);CHKERRQ(ierr);
    } else {
      ierr = VecCopy(F, D);CHKERRQ(ierr);
    }

    powell = PETSC_FALSE;
    if (qn->restart_type == SNES_QN_RESTART_POWELL) {
      /* check restart by Powell's Criterion: |F^T H_0 Fold| > 0.2 * |Fold^T H_0 Fold| */
      ierr = VecDotBegin(Dold, Dold, &DolddotDold);CHKERRQ(ierr);
      ierr = VecDotBegin(Dold, D, &DolddotD);CHKERRQ(ierr);
      ierr = VecDotBegin(D, D, &DdotD);CHKERRQ(ierr);
      ierr = VecDotBegin(Y, D, &YdotD);CHKERRQ(ierr);
      ierr = VecDotEnd(Dold, Dold, &DolddotDold);CHKERRQ(ierr);
      ierr = VecDotEnd(Dold, D, &DolddotD);CHKERRQ(ierr);
      ierr = VecDotEnd(D, D, &DdotD);CHKERRQ(ierr);
      ierr = VecDotEnd(Y, D, &YdotD);CHKERRQ(ierr);
      if (PetscAbs(PetscRealPart(DolddotD)) > qn->powell_gamma*PetscAbs(PetscRealPart(DolddotDold))) powell = PETSC_TRUE;
    }
    periodic = PETSC_FALSE;
    if (qn->restart_type == SNES_QN_RESTART_PERIODIC) {
      if (i_r>qn->m-1) periodic = PETSC_TRUE;
    }
    /* restart if either powell or periodic restart is satisfied. */
    if (powell || periodic) {
      if (qn->monitor) {
        ierr = PetscViewerASCIIAddTab(qn->monitor,((PetscObject)snes)->tablevel+2);CHKERRQ(ierr);
        ierr = PetscViewerASCIIPrintf(qn->monitor, "restart! |%14.12e| > %4.2f*|%14.12e| or i_r = %d\n", PetscRealPart(DolddotD), qn->powell_gamma, PetscRealPart(DolddotDold), i_r);CHKERRQ(ierr);
        ierr = PetscViewerASCIISubtractTab(qn->monitor,((PetscObject)snes)->tablevel+2);CHKERRQ(ierr);
      }
      i_r = -1;
      /* general purpose update */
      if (snes->ops->update) {
        ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
      }
      if (qn->scale_type == SNES_QN_SCALE_JACOBIAN) {
        ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr);
      }
    }
    /* general purpose update */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }
  }
  if (i == snes->max_its) {
    ierr = PetscInfo1(snes, "Maximum number of iterations has been reached: %D\n", snes->max_its);CHKERRQ(ierr);
    if (!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT;
  }
  PetscFunctionReturn(0);
}
Ejemplo n.º 14
0
Archivo: tr.c Proyecto: Kun-Qu/petsc
static PetscErrorCode SNESSolve_TR(SNES snes)
{
  SNES_TR             *neP = (SNES_TR*)snes->data;
  Vec                 X,F,Y,G,Ytmp;
  PetscErrorCode      ierr;
  PetscInt            maxits,i,lits;
  MatStructure        flg = DIFFERENT_NONZERO_PATTERN;
  PetscReal           rho,fnorm,gnorm,gpnorm,xnorm=0,delta,nrm,ynorm,norm1;
  PetscScalar         cnorm;
  KSP                 ksp;
  SNESConvergedReason reason = SNES_CONVERGED_ITERATING;
  PetscBool           conv = PETSC_FALSE,breakout = PETSC_FALSE;
  PetscBool          domainerror;

  PetscFunctionBegin;
  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 */
  G		= snes->work[1];
  Ytmp          = snes->work[2];

  ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
  snes->iter = 0;
  ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);

  if (!snes->vec_func_init_set) {
    ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);          /* F(X) */
    ierr = SNESGetFunctionDomainError(snes, &domainerror);CHKERRQ(ierr);
    if (domainerror) {
      snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
      PetscFunctionReturn(0);
    }
  } else {
    snes->vec_func_init_set = PETSC_FALSE;
  }

  if (!snes->norm_init_set) {
    ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr);             /* fnorm <- || F || */
    if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number");
  } else {
    fnorm = snes->norm_init;
    snes->norm_init_set = PETSC_FALSE;
  }

  ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
  snes->norm = fnorm;
  ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
  delta = neP->delta0*fnorm;         
  neP->delta = delta;
  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,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
  if (snes->reason) PetscFunctionReturn(0);

  /* Set the stopping criteria to use the More' trick. */
  ierr = PetscOptionsGetBool(PETSC_NULL,"-snes_tr_ksp_regular_convergence_test",&conv,PETSC_NULL);CHKERRQ(ierr);
  if (!conv) {
    SNES_TR_KSPConverged_Ctx *ctx;
    ierr = SNESGetKSP(snes,&ksp);CHKERRQ(ierr);
    ierr = PetscNew(SNES_TR_KSPConverged_Ctx,&ctx);CHKERRQ(ierr);
    ctx->snes = snes;
    ierr = KSPDefaultConvergedCreate(&ctx->ctx);CHKERRQ(ierr);
    ierr = KSPSetConvergenceTest(ksp,SNES_TR_KSPConverged_Private,ctx,SNES_TR_KSPConverged_Destroy);CHKERRQ(ierr);
    ierr = PetscInfo(snes,"Using Krylov convergence test SNES_TR_KSPConverged_Private\n");CHKERRQ(ierr);
  }
 
  for (i=0; i<maxits; i++) {

    /* Call general purpose update function */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }

    /* Solve J Y = F, where J is Jacobian matrix */
    ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr);
    ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre,flg);CHKERRQ(ierr);
    ierr = SNES_KSPSolve(snes,snes->ksp,F,Ytmp);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);
    ierr = VecNorm(Ytmp,NORM_2,&nrm);CHKERRQ(ierr);
    norm1 = nrm;
    while(1) {
      ierr = VecCopy(Ytmp,Y);CHKERRQ(ierr);
      nrm = norm1;

      /* Scale Y if need be and predict new value of F norm */
      if (nrm >= delta) {
        nrm = delta/nrm;
        gpnorm = (1.0 - nrm)*fnorm;
        cnorm = nrm;
        ierr = PetscInfo1(snes,"Scaling direction by %G\n",nrm);CHKERRQ(ierr);
        ierr = VecScale(Y,cnorm);CHKERRQ(ierr);
        nrm = gpnorm;
        ynorm = delta;
      } else {
        gpnorm = 0.0;
        ierr = PetscInfo(snes,"Direction is in Trust Region\n");CHKERRQ(ierr);
        ynorm = nrm;
      }
      ierr = VecAYPX(Y,-1.0,X);CHKERRQ(ierr);            /* Y <- X - Y */
      ierr = VecCopy(X,snes->vec_sol_update);CHKERRQ(ierr);
      ierr = SNESComputeFunction(snes,Y,G);CHKERRQ(ierr); /*  F(X) */
      ierr = VecNorm(G,NORM_2,&gnorm);CHKERRQ(ierr);      /* gnorm <- || g || */
      if (fnorm == gpnorm) rho = 0.0;
      else rho = (fnorm*fnorm - gnorm*gnorm)/(fnorm*fnorm - gpnorm*gpnorm); 

      /* Update size of trust region */
      if      (rho < neP->mu)  delta *= neP->delta1;
      else if (rho < neP->eta) delta *= neP->delta2;
      else                     delta *= neP->delta3;
      ierr = PetscInfo3(snes,"fnorm=%G, gnorm=%G, ynorm=%G\n",fnorm,gnorm,ynorm);CHKERRQ(ierr);
      ierr = PetscInfo3(snes,"gpred=%G, rho=%G, delta=%G\n",gpnorm,rho,delta);CHKERRQ(ierr);
      neP->delta = delta;
      if (rho > neP->sigma) break;
      ierr = PetscInfo(snes,"Trying again in smaller region\n");CHKERRQ(ierr);
      /* check to see if progress is hopeless */
      neP->itflag = PETSC_FALSE;
      ierr = SNES_TR_Converged_Private(snes,snes->iter,xnorm,ynorm,fnorm,&reason,snes->cnvP);CHKERRQ(ierr);
      if (!reason) { ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&reason,snes->cnvP);CHKERRQ(ierr); }
      if (reason) {
        /* We're not progressing, so return with the current iterate */
        ierr = SNESMonitor(snes,i+1,fnorm);CHKERRQ(ierr);
        breakout = PETSC_TRUE;
        break;
      }
      snes->numFailures++;
    }
    if (!breakout) {
      /* Update function and solution vectors */
      fnorm = gnorm;
      ierr = VecCopy(G,F);CHKERRQ(ierr);
      ierr = VecCopy(Y,X);CHKERRQ(ierr);
      /* 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 || */
      neP->itflag = PETSC_TRUE;
      if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); }
      ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&reason,snes->cnvP);CHKERRQ(ierr);
      if (reason) break;
    } else {
      break;
    }
  }
  if (i == maxits) {
    ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr);
    if (!reason) reason = SNES_DIVERGED_MAX_IT;
  }
  ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
  snes->reason = reason;
  ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}
Ejemplo n.º 15
0
Archivo: viss.c Proyecto: petsc/petsc
/*
   SNESSolve_VINEWTONSSLS - Solves the complementarity problem with a semismooth Newton
   method using a line search.

   Input Parameters:
.  snes - the SNES context

   Application Interface Routine: SNESSolve()

   Notes:
   This implements essentially a semismooth Newton method with a
   line search. The default line search does not do any line search
   but rather takes a full Newton step.

   Developer Note: the code in this file should be slightly modified so that this routine need not exist and the SNESSolve_NEWTONLS() routine is called directly with the appropriate wrapped function and Jacobian evaluations

*/
PetscErrorCode SNESSolve_VINEWTONSSLS(SNES snes)
{
  SNES_VINEWTONSSLS    *vi = (SNES_VINEWTONSSLS*)snes->data;
  PetscErrorCode       ierr;
  PetscInt             maxits,i,lits;
  SNESLineSearchReason lssucceed;
  PetscReal            gnorm,xnorm=0,ynorm;
  Vec                  Y,X,F;
  KSPConvergedReason   kspreason;
  DM                   dm;
  DMSNES               sdm;

  PetscFunctionBegin;
  ierr = SNESGetDM(snes,&dm);CHKERRQ(ierr);
  ierr = DMGetDMSNES(dm,&sdm);CHKERRQ(ierr);

  vi->computeuserfunction   = sdm->ops->computefunction;
  sdm->ops->computefunction = SNESVIComputeFunction;

  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       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->iter = 0;
  snes->norm = 0.0;
  ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);

  ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr);
  ierr = SNESComputeFunction(snes,X,vi->phi);CHKERRQ(ierr);
  if (snes->domainerror) {
    snes->reason              = SNES_DIVERGED_FUNCTION_DOMAIN;
    sdm->ops->computefunction = vi->computeuserfunction;
    PetscFunctionReturn(0);
  }
  /* Compute Merit function */
  ierr = SNESVIComputeMeritFunction(vi->phi,&vi->merit,&vi->phinorm);CHKERRQ(ierr);

  ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr);        /* xnorm <- ||x||  */
  ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr);
  SNESCheckFunctionNorm(snes,vi->merit);

  ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->norm = vi->phinorm;
  ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
  ierr       = SNESLogConvergenceHistory(snes,vi->phinorm,0);CHKERRQ(ierr);
  ierr       = SNESMonitor(snes,0,vi->phinorm);CHKERRQ(ierr);

  /* test convergence */
  ierr = (*snes->ops->converged)(snes,0,0.0,0.0,vi->phinorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
  if (snes->reason) {
    sdm->ops->computefunction = vi->computeuserfunction;
    PetscFunctionReturn(0);
  }

  for (i=0; i<maxits; i++) {

    /* Call general purpose update function */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }

    /* Solve J Y = Phi, where J is the semismooth jacobian */

    /* Get the jacobian -- note that the function must be the original function for snes_fd and snes_fd_color to work for this*/
    sdm->ops->computefunction = vi->computeuserfunction;
    ierr                      = SNESComputeJacobian(snes,X,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
    SNESCheckJacobianDomainerror(snes);
    sdm->ops->computefunction = SNESVIComputeFunction;

    /* Get the diagonal shift and row scaling vectors */
    ierr = SNESVIComputeBsubdifferentialVectors(snes,X,F,snes->jacobian,vi->Da,vi->Db);CHKERRQ(ierr);
    /* Compute the semismooth jacobian */
    ierr = SNESVIComputeJacobian(snes->jacobian,snes->jacobian_pre,vi->Da,vi->Db);CHKERRQ(ierr);
    /* Compute the merit function gradient */
    ierr = SNESVIComputeMeritFunctionGradient(snes->jacobian,vi->phi,vi->dpsi);CHKERRQ(ierr);
    ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
    ierr = KSPSolve(snes->ksp,vi->phi,Y);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              = 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 = vi->phinorm;
    ierr = SNESLineSearchApply(snes->linesearch, X, vi->phi, &gnorm, Y);CHKERRQ(ierr);
    ierr = SNESLineSearchGetReason(snes->linesearch, &lssucceed);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)vi->phinorm,(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;
      sdm->ops->computefunction = vi->computeuserfunction;
      PetscFunctionReturn(0);
    }
    if (lssucceed) {
      if (++snes->numFailures >= snes->maxFailures) {
        PetscBool ismin;
        snes->reason = SNES_DIVERGED_LINE_SEARCH;
        ierr         = SNESVICheckLocalMin_Private(snes,snes->jacobian,vi->phi,X,gnorm,&ismin);CHKERRQ(ierr);
        if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
        break;
      }
    }
    /* Update function and solution vectors */
    vi->phinorm = gnorm;
    vi->merit   = 0.5*vi->phinorm*vi->phinorm;
    /* Monitor convergence */
    ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
    snes->iter = i+1;
    snes->norm = vi->phinorm;
    snes->xnorm = xnorm;
    snes->ynorm = ynorm;
    ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
    ierr       = SNESLogConvergenceHistory(snes,snes->norm,lits);CHKERRQ(ierr);
    ierr       = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);
    /* Test for convergence, xnorm = || X || */
    if (snes->ops->converged != SNESConvergedSkip) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); }
    ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,vi->phinorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
    if (snes->reason) break;
  }
  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;
  }
  sdm->ops->computefunction = vi->computeuserfunction;
  PetscFunctionReturn(0);
}
Ejemplo n.º 16
0
PetscErrorCode SNESSolve_Test(SNES snes)
{
  Mat            A = snes->jacobian,B;
  Vec            x = snes->vec_sol,f = snes->vec_func,f1 = snes->vec_sol_update;
  PetscErrorCode ierr;
  PetscInt       i;
  PetscReal      nrm,gnorm;
  SNES_Test      *neP = (SNES_Test*)snes->data;
  PetscErrorCode (*objective)(SNES,Vec,PetscReal*,void*);
  void           *ctx;
  PetscReal      fnorm,f1norm,dnorm;

  PetscFunctionBegin;
  if (A != snes->jacobian_pre) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Cannot test with alternative preconditioner");

  ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Testing hand-coded Jacobian, if the ratio is\n");CHKERRQ(ierr);
  ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"O(1.e-8), the hand-coded Jacobian is probably correct.\n");CHKERRQ(ierr);
  if (!neP->complete_print) {
    ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Run with -snes_test_display to show difference\n");CHKERRQ(ierr);
    ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"of hand-coded and finite difference Jacobian.\n");CHKERRQ(ierr);
  }

  for (i=0; i<3; i++) {
    void                     *functx;
    static const char *const loc[] = {"user-defined state","constant state -1.0","constant state 1.0"};
    PetscInt                 m,n,M,N;

    if (i == 1) {
      ierr = VecSet(x,-1.0);CHKERRQ(ierr);
    } else if (i == 2) {
      ierr = VecSet(x,1.0);CHKERRQ(ierr);
    }

    /* evaluate the function at this point because SNESComputeJacobianDefaultColor() assumes that the function has been evaluated and put into snes->vec_func */
    ierr = SNESComputeFunction(snes,x,f);CHKERRQ(ierr);
    if (snes->domainerror) {
      ierr              = PetscPrintf(PetscObjectComm((PetscObject)snes),"Domain error at %s\n",loc[i]);CHKERRQ(ierr);
      snes->domainerror = PETSC_FALSE;
      continue;
    }

    /* compute both versions of Jacobian */
    ierr = SNESComputeJacobian(snes,x,A,A);CHKERRQ(ierr);

    ierr = MatCreate(PetscObjectComm((PetscObject)A),&B);CHKERRQ(ierr);
    ierr = MatGetSize(A,&M,&N);CHKERRQ(ierr);
    ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
    ierr = MatSetSizes(B,m,n,M,N);CHKERRQ(ierr);
    ierr = MatSetType(B,((PetscObject)A)->type_name);CHKERRQ(ierr);
    ierr = MatSetUp(B);CHKERRQ(ierr);
    ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);

    ierr = SNESGetFunction(snes,NULL,NULL,&functx);CHKERRQ(ierr);
    ierr = SNESComputeJacobianDefault(snes,x,B,B,functx);CHKERRQ(ierr);
    if (neP->complete_print) {
      MPI_Comm    comm;
      PetscViewer viewer;
      ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Finite difference Jacobian (%s)\n",loc[i]);CHKERRQ(ierr);
      ierr = PetscObjectGetComm((PetscObject)B,&comm);CHKERRQ(ierr);
      ierr = PetscViewerASCIIGetStdout(comm,&viewer);CHKERRQ(ierr);
      ierr = MatView(B,viewer);CHKERRQ(ierr);
    }
    /* compare */
    ierr = MatAYPX(B,-1.0,A,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
    ierr = MatNorm(B,NORM_FROBENIUS,&nrm);CHKERRQ(ierr);
    ierr = MatNorm(A,NORM_FROBENIUS,&gnorm);CHKERRQ(ierr);
    if (neP->complete_print) {
      MPI_Comm    comm;
      PetscViewer viewer;
      ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Hand-coded Jacobian (%s)\n",loc[i]);CHKERRQ(ierr);
      ierr = PetscObjectGetComm((PetscObject)B,&comm);CHKERRQ(ierr);
      ierr = PetscViewerASCIIGetStdout(comm,&viewer);CHKERRQ(ierr);
      ierr = MatView(A,viewer);CHKERRQ(ierr);
      ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Hand-coded minus finite difference Jacobian (%s)\n",loc[i]);CHKERRQ(ierr);
      ierr = MatView(B,viewer);CHKERRQ(ierr);
    }
    if (!gnorm) gnorm = 1; /* just in case */
    ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Norm of matrix ratio %g difference %g (%s)\n",(double)(nrm/gnorm),(double)nrm,loc[i]);CHKERRQ(ierr);

    ierr = SNESGetObjective(snes,&objective,&ctx);CHKERRQ(ierr);
    if (objective) {
      ierr = SNESComputeFunction(snes,x,f);CHKERRQ(ierr);
      ierr = VecNorm(f,NORM_2,&fnorm);CHKERRQ(ierr);
      if (neP->complete_print) {
        PetscViewer viewer;
        ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Hand-coded Function (%s)\n",loc[i]);CHKERRQ(ierr);
        ierr = PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&viewer);CHKERRQ(ierr);
        ierr = VecView(f,viewer);CHKERRQ(ierr);
      }
      ierr = SNESObjectiveComputeFunctionDefaultFD(snes,x,f1,NULL);CHKERRQ(ierr);
      ierr = VecNorm(f1,NORM_2,&f1norm);CHKERRQ(ierr);
      if (neP->complete_print) {
        PetscViewer viewer;
        ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Finite-Difference Function (%s)\n",loc[i]);CHKERRQ(ierr);
        ierr = PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&viewer);CHKERRQ(ierr);
        ierr = VecView(f1,viewer);CHKERRQ(ierr);
      }
      /* compare the two */
      ierr = VecAXPY(f,-1.0,f1);CHKERRQ(ierr);
      ierr = VecNorm(f,NORM_2,&dnorm);CHKERRQ(ierr);
      if (!fnorm) fnorm = 1.;
      ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Norm of function ratio %g difference %g (%s)\n",dnorm/fnorm,dnorm,loc[i]);CHKERRQ(ierr);
      if (neP->complete_print) {
        PetscViewer viewer;
        ierr = PetscPrintf(PetscObjectComm((PetscObject)snes),"Difference (%s)\n",loc[i]);CHKERRQ(ierr);
        ierr = PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)snes),&viewer);CHKERRQ(ierr);
        ierr = VecView(f,viewer);CHKERRQ(ierr);
      }
    }
    ierr = MatDestroy(&B);CHKERRQ(ierr);
  }

  /*
   Abort after the first iteration due to the jacobian not being valid.
  */

  SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"SNESTest aborts after Jacobian test");
  PetscFunctionReturn(0);
}
Ejemplo n.º 17
0
PetscErrorCode SNESSolve_NEWTONLS(SNES snes)
{
  PetscErrorCode      ierr;
  PetscInt            maxits,i,lits;
  PetscBool           lssucceed;
  MatStructure        flg = DIFFERENT_NONZERO_PATTERN;
  PetscReal           fnorm,gnorm,xnorm,ynorm;
  Vec                 Y,X,F,G,W,FPC;
  KSPConvergedReason  kspreason;
  PetscBool           domainerror;
  SNESLineSearch      linesearch;
  SNESConvergedReason reason;

  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->vec_sol_update; /* newton step */
  G             = snes->work[0];
  W             = snes->work[1];

  ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
  snes->iter = 0;
  snes->norm = 0.0;
  ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
  ierr = SNESGetSNESLineSearch(snes, &linesearch);CHKERRQ(ierr);
  if (!snes->vec_func_init_set) {
    ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
    ierr = SNESGetFunctionDomainError(snes, &domainerror);CHKERRQ(ierr);
    if (domainerror) {
      snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
      PetscFunctionReturn(0);
    }
  } else {
    snes->vec_func_init_set = PETSC_FALSE;
  }
  if (!snes->norm_init_set) {
    ierr = VecNormBegin(F,NORM_2,&fnorm);CHKERRQ(ierr);        /* fnorm <- ||F||  */
    ierr = VecNormEnd(F,NORM_2,&fnorm);CHKERRQ(ierr);
    if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number");
  } else {
    fnorm = snes->norm_init;
    snes->norm_init_set = PETSC_FALSE;
  }
  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++) {

    /* Call general purpose update function */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }

    /* apply the nonlinear preconditioner if it's right preconditioned */
    if (snes->pc && snes->pcside == PC_RIGHT) {
      ierr = SNESSetInitialFunction(snes->pc, F);CHKERRQ(ierr);
      ierr = SNESSetInitialFunctionNorm(snes->pc, fnorm);CHKERRQ(ierr);
      ierr = SNESSolve(snes->pc, snes->vec_rhs, X);CHKERRQ(ierr);
      ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
      if (reason < 0  && reason != SNES_DIVERGED_MAX_IT) {
        snes->reason = SNES_DIVERGED_INNER;
        PetscFunctionReturn(0);
      }
      ierr = SNESGetFunction(snes->pc, &FPC, PETSC_NULL, PETSC_NULL);CHKERRQ(ierr);
      ierr = VecCopy(FPC, F);CHKERRQ(ierr);
      ierr = SNESGetFunctionNorm(snes->pc, &fnorm);CHKERRQ(ierr);
    }

    /* Solve J Y = F, where J is Jacobian matrix */
    ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr);
    ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre,flg);CHKERRQ(ierr);
    ierr = SNES_KSPSolve(snes,snes->ksp,F,Y);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 = 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 (PetscLogPrintInfo){
      ierr = SNESNEWTONLSCheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr);
    }

    /* Compute a (scaled) negative update in the line search routine:
         X <- X - lambda*Y
       and evaluate F = function(X) (depends on the line search).
    */
    gnorm = fnorm;
    ierr = SNESLineSearchApply(linesearch, X, F, &fnorm, Y);CHKERRQ(ierr);
    ierr = SNESLineSearchGetSuccess(linesearch, &lssucceed);CHKERRQ(ierr);
    ierr = SNESLineSearchGetNorms(linesearch, &xnorm, &fnorm, &ynorm);CHKERRQ(ierr);
    ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",(double)gnorm,(double)fnorm,(double)ynorm,(int)lssucceed);CHKERRQ(ierr);
    if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break;
    ierr = SNESGetFunctionDomainError(snes, &domainerror);CHKERRQ(ierr);
    if (domainerror) {
      snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
      PetscFunctionReturn(0);
    }
    if (!lssucceed) {
      if (snes->stol*xnorm > ynorm) {
        snes->reason = SNES_CONVERGED_SNORM_RELATIVE;
        PetscFunctionReturn(0);
      }
      if (++snes->numFailures >= snes->maxFailures) {
        PetscBool  ismin;
        snes->reason = SNES_DIVERGED_LINE_SEARCH;
        ierr = SNESNEWTONLSCheckLocalMin_Private(snes,snes->jacobian,F,W,fnorm,&ismin);CHKERRQ(ierr);
        if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
        break;
      }
    }
    /* 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 */
    ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
    if (snes->reason) break;
  }
  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);
}
Ejemplo n.º 18
0
static PetscErrorCode SNESSolve_QN(SNES snes)
{
  PetscErrorCode       ierr;
  SNES_QN              *qn = (SNES_QN*) snes->data;
  Vec                  X,Xold;
  Vec                  F,W;
  Vec                  Y,D,Dold;
  PetscInt             i, i_r;
  PetscReal            fnorm,xnorm,ynorm,gnorm;
  SNESLineSearchReason lssucceed;
  PetscBool            powell,periodic;
  PetscScalar          DolddotD,DolddotDold;
  SNESConvergedReason  reason;

  /* basically just a regular newton's method except for the application of the Jacobian */

  PetscFunctionBegin;

  if (snes->xl || snes->xu || snes->ops->computevariablebounds) {
    SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE, "SNES solver %s does not support bounds", ((PetscObject)snes)->type_name);
  }

  ierr = PetscCitationsRegister(SNESCitation,&SNEScite);CHKERRQ(ierr);
  F    = snes->vec_func;                /* residual vector */
  Y    = snes->vec_sol_update;          /* search direction generated by J^-1D*/
  W    = snes->work[3];
  X    = snes->vec_sol;                 /* solution vector */
  Xold = snes->work[0];

  /* directions generated by the preconditioned problem with F_pre = F or x - M(x, b) */
  D    = snes->work[1];
  Dold = snes->work[2];

  snes->reason = SNES_CONVERGED_ITERATING;

  ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->iter = 0;
  snes->norm = 0.;
  ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);

  if (snes->pc && snes->pcside == PC_LEFT && snes->functype == SNES_FUNCTION_PRECONDITIONED) {
    ierr = SNESApplyNPC(snes,X,NULL,F);CHKERRQ(ierr);
    ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
    if (reason < 0  && reason != SNES_DIVERGED_MAX_IT) {
      snes->reason = SNES_DIVERGED_INNER;
      PetscFunctionReturn(0);
    }
    ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr);
  } else {
    if (!snes->vec_func_init_set) {
      ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
    } else snes->vec_func_init_set = PETSC_FALSE;

    ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr);
    SNESCheckFunctionNorm(snes,fnorm);
  }
  if (snes->pc && snes->pcside == PC_LEFT && snes->functype == SNES_FUNCTION_UNPRECONDITIONED) {
      ierr = SNESApplyNPC(snes,X,F,D);CHKERRQ(ierr);
      ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
      if (reason < 0  && reason != SNES_DIVERGED_MAX_IT) {
        snes->reason = SNES_DIVERGED_INNER;
        PetscFunctionReturn(0);
      }
  } else {
    ierr = VecCopy(F,D);CHKERRQ(ierr);
  }

  ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->norm = fnorm;
  ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
  ierr       = SNESLogConvergenceHistory(snes,fnorm,0);CHKERRQ(ierr);
  ierr       = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr);

  /* test convergence */
  ierr = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
  if (snes->reason) PetscFunctionReturn(0);

  if (snes->pc && snes->pcside == PC_RIGHT) {
    ierr = PetscLogEventBegin(SNES_NPCSolve,snes->pc,X,0,0);CHKERRQ(ierr);
    ierr = SNESSolve(snes->pc,snes->vec_rhs,X);CHKERRQ(ierr);
    ierr = PetscLogEventEnd(SNES_NPCSolve,snes->pc,X,0,0);CHKERRQ(ierr);
    ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
    if (reason < 0 && reason != SNES_DIVERGED_MAX_IT) {
      snes->reason = SNES_DIVERGED_INNER;
      PetscFunctionReturn(0);
    }
    ierr = SNESGetNPCFunction(snes,F,&fnorm);CHKERRQ(ierr);
    ierr = VecCopy(F,D);CHKERRQ(ierr);
  }

  /* scale the initial update */
  if (qn->scale_type == SNES_QN_SCALE_JACOBIAN) {
    ierr = SNESComputeJacobian(snes,X,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
    ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
  }

  for (i = 0, i_r = 0; i < snes->max_its; i++, i_r++) {
    if (qn->scale_type == SNES_QN_SCALE_SHANNO && i_r > 0) {
      PetscScalar ff,xf;
      ierr = VecCopy(Dold,Y);CHKERRQ(ierr);
      ierr = VecCopy(Xold,W);CHKERRQ(ierr);
      ierr = VecAXPY(Y,-1.0,D);CHKERRQ(ierr);
      ierr = VecAXPY(W,-1.0,X);CHKERRQ(ierr);
      ierr = VecDotBegin(Y,Y,&ff);CHKERRQ(ierr);
      ierr = VecDotBegin(W,Y,&xf);CHKERRQ(ierr);
      ierr = VecDotEnd(Y,Y,&ff);CHKERRQ(ierr);
      ierr = VecDotEnd(W,Y,&xf);CHKERRQ(ierr);
      qn->scaling = PetscRealPart(xf)/PetscRealPart(ff);
    }
    switch (qn->type) {
    case SNES_QN_BADBROYDEN:
      ierr = SNESQNApply_BadBroyden(snes,i_r,Y,X,Xold,D,Dold);CHKERRQ(ierr);
      break;
    case SNES_QN_BROYDEN:
      ierr = SNESQNApply_Broyden(snes,i_r,Y,X,Xold,D);CHKERRQ(ierr);
      break;
    case SNES_QN_LBFGS:
      SNESQNApply_LBFGS(snes,i_r,Y,X,Xold,D,Dold);CHKERRQ(ierr);
      break;
    }
    /* line search for lambda */
    ynorm = 1; gnorm = fnorm;
    ierr  = VecCopy(D, Dold);CHKERRQ(ierr);
    ierr  = VecCopy(X, Xold);CHKERRQ(ierr);
    ierr  = SNESLineSearchApply(snes->linesearch, X, F, &fnorm, Y);CHKERRQ(ierr);
    if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break;
    ierr = SNESLineSearchGetReason(snes->linesearch, &lssucceed);CHKERRQ(ierr);
    ierr = SNESLineSearchGetNorms(snes->linesearch, &xnorm, &fnorm, &ynorm);CHKERRQ(ierr);
    if (lssucceed) {
      if (++snes->numFailures >= snes->maxFailures) {
        snes->reason = SNES_DIVERGED_LINE_SEARCH;
        break;
      }
    }
    if (qn->scale_type == SNES_QN_SCALE_LINESEARCH) {
      ierr = SNESLineSearchGetLambda(snes->linesearch, &qn->scaling);CHKERRQ(ierr);
    }

    /* convergence monitoring */
    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->pc && snes->pcside == PC_RIGHT) {
      ierr = PetscLogEventBegin(SNES_NPCSolve,snes->pc,X,0,0);CHKERRQ(ierr);
      ierr = SNESSolve(snes->pc,snes->vec_rhs,X);CHKERRQ(ierr);
      ierr = PetscLogEventEnd(SNES_NPCSolve,snes->pc,X,0,0);CHKERRQ(ierr);
      ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
      if (reason < 0 && reason != SNES_DIVERGED_MAX_IT) {
        snes->reason = SNES_DIVERGED_INNER;
        PetscFunctionReturn(0);
      }
      ierr = SNESGetNPCFunction(snes,F,&fnorm);CHKERRQ(ierr);
    }

    ierr = SNESSetIterationNumber(snes, i+1);CHKERRQ(ierr);
    snes->norm = fnorm;

    ierr = SNESLogConvergenceHistory(snes,snes->norm,snes->iter);CHKERRQ(ierr);
    ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);
    /* set parameter for default relative tolerance convergence test */
    ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
    if (snes->reason) PetscFunctionReturn(0);
    if (snes->pc && snes->pcside == PC_LEFT && snes->functype == SNES_FUNCTION_UNPRECONDITIONED) {
      ierr = SNESApplyNPC(snes,X,F,D);CHKERRQ(ierr);
      ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
      if (reason < 0  && reason != SNES_DIVERGED_MAX_IT) {
        snes->reason = SNES_DIVERGED_INNER;
        PetscFunctionReturn(0);
      }
    } else {
      ierr = VecCopy(F, D);CHKERRQ(ierr);
    }
    powell = PETSC_FALSE;
    if (qn->restart_type == SNES_QN_RESTART_POWELL) {
      /* check restart by Powell's Criterion: |F^T H_0 Fold| > 0.2 * |Fold^T H_0 Fold| */
      if (qn->scale_type == SNES_QN_SCALE_JACOBIAN) {
        ierr = MatMult(snes->jacobian_pre,Dold,W);CHKERRQ(ierr);
      } else {
        ierr = VecCopy(Dold,W);CHKERRQ(ierr);
      }
      ierr = VecDotBegin(W, Dold, &DolddotDold);CHKERRQ(ierr);
      ierr = VecDotBegin(W, D, &DolddotD);CHKERRQ(ierr);
      ierr = VecDotEnd(W, Dold, &DolddotDold);CHKERRQ(ierr);
      ierr = VecDotEnd(W, D, &DolddotD);CHKERRQ(ierr);
      if (PetscAbs(PetscRealPart(DolddotD)) > qn->powell_gamma*PetscAbs(PetscRealPart(DolddotDold))) powell = PETSC_TRUE;
    }
    periodic = PETSC_FALSE;
    if (qn->restart_type == SNES_QN_RESTART_PERIODIC) {
      if (i_r>qn->m-1) periodic = PETSC_TRUE;
    }
    /* restart if either powell or periodic restart is satisfied. */
    if (powell || periodic) {
      if (qn->monitor) {
        ierr = PetscViewerASCIIAddTab(qn->monitor,((PetscObject)snes)->tablevel+2);CHKERRQ(ierr);
        ierr = PetscViewerASCIIPrintf(qn->monitor, "restart! |%14.12e| > %4.2f*|%14.12e| or i_r = %d\n", PetscRealPart(DolddotD), qn->powell_gamma, PetscRealPart(DolddotDold), i_r);CHKERRQ(ierr);
        ierr = PetscViewerASCIISubtractTab(qn->monitor,((PetscObject)snes)->tablevel+2);CHKERRQ(ierr);
      }
      i_r = -1;
      /* general purpose update */
      if (snes->ops->update) {
        ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
      }
      if (qn->scale_type == SNES_QN_SCALE_JACOBIAN) {
        ierr = SNESComputeJacobian(snes,X,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
      }
    }
    /* general purpose update */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }
  }
  if (i == snes->max_its) {
    ierr = PetscInfo1(snes, "Maximum number of iterations has been reached: %D\n", snes->max_its);CHKERRQ(ierr);
    if (!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT;
  }
  PetscFunctionReturn(0);
}
Ejemplo n.º 19
0
int main(int argc, char **argv)
{
  SNES           snes;                 /* nonlinear solver */
  Vec            u,r;                  /* solution, residual vectors */
  Mat            A,J;                  /* Jacobian matrix */
  MatNullSpace   nullSpace;            /* May be necessary for pressure */
  AppCtx         user;                 /* user-defined work context */
  JacActionCtx   userJ;                /* context for Jacobian MF action */
  PetscInt       its;                  /* iterations for convergence */
  PetscReal      error         = 0.0;  /* L_2 error in the solution */
  const PetscInt numComponents = NUM_BASIS_COMPONENTS_TOTAL;
  PetscErrorCode ierr;

  ierr = PetscInitialize(&argc, &argv, NULL, help);CHKERRQ(ierr);
  ierr = ProcessOptions(PETSC_COMM_WORLD, &user);CHKERRQ(ierr);
  ierr = SNESCreate(PETSC_COMM_WORLD, &snes);CHKERRQ(ierr);
  ierr = CreateMesh(PETSC_COMM_WORLD, &user, &user.dm);CHKERRQ(ierr);
  ierr = SNESSetDM(snes, user.dm);CHKERRQ(ierr);

  ierr = SetupExactSolution(user.dm, &user);CHKERRQ(ierr);
  ierr = SetupQuadrature(&user);CHKERRQ(ierr);
  ierr = SetupSection(user.dm, &user);CHKERRQ(ierr);

  ierr = DMCreateGlobalVector(user.dm, &u);CHKERRQ(ierr);
  ierr = VecDuplicate(u, &r);CHKERRQ(ierr);

  ierr = DMCreateMatrix(user.dm, MATAIJ, &J);CHKERRQ(ierr);
  if (user.jacobianMF) {
    PetscInt M, m, N, n;

    ierr = MatGetSize(J, &M, &N);CHKERRQ(ierr);
    ierr = MatGetLocalSize(J, &m, &n);CHKERRQ(ierr);
    ierr = MatCreate(PETSC_COMM_WORLD, &A);CHKERRQ(ierr);
    ierr = MatSetSizes(A, m, n, M, N);CHKERRQ(ierr);
    ierr = MatSetType(A, MATSHELL);CHKERRQ(ierr);
    ierr = MatSetUp(A);CHKERRQ(ierr);
    ierr = MatShellSetOperation(A, MATOP_MULT, (void (*)(void))FormJacobianAction);CHKERRQ(ierr);

    userJ.dm   = user.dm;
    userJ.J    = J;
    userJ.user = &user;

    ierr = DMCreateLocalVector(user.dm, &userJ.u);CHKERRQ(ierr);
    ierr = DMPlexProjectFunctionLocal(user.dm, numComponents, user.exactFuncs, INSERT_BC_VALUES, userJ.u);CHKERRQ(ierr);
    ierr = MatShellSetContext(A, &userJ);CHKERRQ(ierr);
  } else {
    A = J;
  }
  ierr = CreatePressureNullSpace(user.dm, &user, &nullSpace);CHKERRQ(ierr);
  ierr = MatSetNullSpace(J, nullSpace);CHKERRQ(ierr);
  if (A != J) {
    ierr = MatSetNullSpace(A, nullSpace);CHKERRQ(ierr);
  }

  ierr = DMSNESSetFunctionLocal(user.dm,  (PetscErrorCode (*)(DM,Vec,Vec,void*))DMPlexComputeResidualFEM,&user);CHKERRQ(ierr);
  ierr = DMSNESSetJacobianLocal(user.dm,  (PetscErrorCode (*)(DM,Vec,Mat,Mat,MatStructure*,void*))DMPlexComputeJacobianFEM,&user);CHKERRQ(ierr);
  ierr = SNESSetJacobian(snes, A, J, NULL, NULL);CHKERRQ(ierr);

  ierr = SNESSetFromOptions(snes);CHKERRQ(ierr);

  ierr = DMPlexProjectFunction(user.dm, numComponents, user.exactFuncs, INSERT_ALL_VALUES, u);CHKERRQ(ierr);
  if (user.showInitial) {ierr = DMVecViewLocal(user.dm, u, PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);}
  if (user.runType == RUN_FULL) {
    PetscScalar (*initialGuess[numComponents])(const PetscReal x[]);
    PetscInt c;

    for (c = 0; c < numComponents; ++c) initialGuess[c] = zero;
    ierr = DMPlexProjectFunction(user.dm, numComponents, initialGuess, INSERT_VALUES, u);CHKERRQ(ierr);
    if (user.showInitial) {ierr = DMVecViewLocal(user.dm, u, PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);}
    if (user.debug) {
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr);
      ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    }
    ierr = SNESSolve(snes, NULL, u);CHKERRQ(ierr);
    ierr = SNESGetIterationNumber(snes, &its);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Number of SNES iterations = %D\n", its);CHKERRQ(ierr);
    ierr = DMPlexComputeL2Diff(user.dm, user.fem.quad, user.exactFuncs, u, &error);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %.3g\n", error);CHKERRQ(ierr);
    if (user.showSolution) {
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Solution\n");CHKERRQ(ierr);
      ierr = VecChop(u, 3.0e-9);CHKERRQ(ierr);
      ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    }
  } else {
    PetscReal res = 0.0;

    /* Check discretization error */
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr);
    ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    ierr = DMPlexComputeL2Diff(user.dm, user.fem.quad, user.exactFuncs, u, &error);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %g\n", error);CHKERRQ(ierr);
    /* Check residual */
    ierr = SNESComputeFunction(snes, u, r);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial Residual\n");CHKERRQ(ierr);
    ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr);
    ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Residual: %g\n", res);CHKERRQ(ierr);
    /* Check Jacobian */
    {
      Vec          b;
      MatStructure flag;
      PetscBool    isNull;

      ierr = SNESComputeJacobian(snes, u, &A, &A, &flag);CHKERRQ(ierr);
      ierr = MatNullSpaceTest(nullSpace, J, &isNull);CHKERRQ(ierr);
      if (!isNull) SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_PLIB, "The null space calculated for the system operator is invalid.");
      ierr = VecDuplicate(u, &b);CHKERRQ(ierr);
      ierr = VecSet(r, 0.0);CHKERRQ(ierr);
      ierr = SNESComputeFunction(snes, r, b);CHKERRQ(ierr);
      ierr = MatMult(A, u, r);CHKERRQ(ierr);
      ierr = VecAXPY(r, 1.0, b);CHKERRQ(ierr);
      ierr = VecDestroy(&b);CHKERRQ(ierr);
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Au - b = Au + F(0)\n");CHKERRQ(ierr);
      ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr);
      ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
      ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr);
      ierr = PetscPrintf(PETSC_COMM_WORLD, "Linear L_2 Residual: %g\n", res);CHKERRQ(ierr);
    }
  }

  if (user.runType == RUN_FULL) {
    PetscViewer viewer;
    Vec         uLocal;

    ierr = PetscViewerCreate(PETSC_COMM_WORLD, &viewer);CHKERRQ(ierr);
    ierr = PetscViewerSetType(viewer, PETSCVIEWERVTK);CHKERRQ(ierr);
    ierr = PetscViewerSetFormat(viewer, PETSC_VIEWER_ASCII_VTK);CHKERRQ(ierr);
    ierr = PetscViewerFileSetName(viewer, "ex62_sol.vtk");CHKERRQ(ierr);

    ierr = DMGetLocalVector(user.dm, &uLocal);CHKERRQ(ierr);
    ierr = DMGlobalToLocalBegin(user.dm, u, INSERT_VALUES, uLocal);CHKERRQ(ierr);
    ierr = DMGlobalToLocalEnd(user.dm, u, INSERT_VALUES, uLocal);CHKERRQ(ierr);

    ierr = PetscObjectReference((PetscObject) user.dm);CHKERRQ(ierr); /* Needed because viewer destroys the DM */
    ierr = PetscObjectReference((PetscObject) uLocal);CHKERRQ(ierr); /* Needed because viewer destroys the Vec */
    ierr = PetscViewerVTKAddField(viewer, (PetscObject) user.dm, DMPlexVTKWriteAll, PETSC_VTK_POINT_FIELD, (PetscObject) uLocal);CHKERRQ(ierr);
    ierr = DMRestoreLocalVector(user.dm, &uLocal);CHKERRQ(ierr);
    ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
  }

  ierr = DestroyQuadrature(&user);CHKERRQ(ierr);
  ierr = MatNullSpaceDestroy(&nullSpace);CHKERRQ(ierr);
  if (user.jacobianMF) {
    ierr = VecDestroy(&userJ.u);CHKERRQ(ierr);
  }
  if (A != J) {
    ierr = MatDestroy(&A);CHKERRQ(ierr);
  }
  ierr = MatDestroy(&J);CHKERRQ(ierr);
  ierr = VecDestroy(&u);CHKERRQ(ierr);
  ierr = VecDestroy(&r);CHKERRQ(ierr);
  ierr = SNESDestroy(&snes);CHKERRQ(ierr);
  ierr = DMDestroy(&user.dm);CHKERRQ(ierr);
  ierr = PetscFinalize();
  return 0;
}
Ejemplo n.º 20
0
PetscErrorCode SNESSolve_LS(SNES snes)
{ 
  SNES_LS            *neP = (SNES_LS*)snes->data;
  PetscErrorCode     ierr;
  PetscInt           maxits,i,lits;
  PetscTruth         lssucceed;
  MatStructure       flg = DIFFERENT_NONZERO_PATTERN;
  PetscReal          fnorm,gnorm,xnorm=0,ynorm;
  Vec                Y,X,F,G,W;
  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 */
  G		= snes->work[1];
  W		= snes->work[2];

  ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
  snes->iter = 0;
  snes->norm = 0.0;
  ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
  ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
  if (snes->domainerror) {
    snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
    PetscFunctionReturn(0);
  }
  ierr = VecNormBegin(F,NORM_2,&fnorm);CHKERRQ(ierr);	/* fnorm <- ||F||  */
  ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr);	/* xnorm <- ||x||  */
  ierr = VecNormEnd(F,NORM_2,&fnorm);CHKERRQ(ierr);
  ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr);
  if PetscIsInfOrNanReal(fnorm) SETERRQ(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);
  SNESMonitor(snes,0,fnorm);

  /* 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++) {

    /* Call general purpose update function */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }

    /* Solve J Y = F, where J is Jacobian matrix */
    ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr);
    ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre,flg);CHKERRQ(ierr);
    ierr = SNES_KSPSolve(snes,snes->ksp,F,Y);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 = 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 (neP->precheckstep) {
      PetscTruth changed_y = PETSC_FALSE;
      ierr = (*neP->precheckstep)(snes,X,Y,neP->precheck,&changed_y);CHKERRQ(ierr);
    }

    if (PetscLogPrintInfo){
      ierr = SNESLSCheckResidual_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 = (*neP->LineSearch)(snes,neP->lsP,X,F,G,Y,W,fnorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr);
    ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",fnorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr);
    if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break;
    if (snes->domainerror) {
      snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
      PetscFunctionReturn(0);
    }
    if (!lssucceed) {
      if (++snes->numFailures >= snes->maxFailures) {
	PetscTruth ismin;
        snes->reason = SNES_DIVERGED_LS_FAILURE;
        ierr = SNESLSCheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr);
        if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
        break;
      }
    }
    /* Update function and solution vectors */
    fnorm = gnorm;
    ierr = VecCopy(G,F);CHKERRQ(ierr);
    ierr = VecCopy(W,X);CHKERRQ(ierr);
    /* Monitor convergence */
    ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr);
    snes->iter = i+1;
    snes->norm = fnorm;
    ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr);
    SNESLogConvHistory(snes,snes->norm,lits);
    SNESMonitor(snes,snes->iter,snes->norm);
    /* 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;
  }
  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);
}
Ejemplo n.º 21
0
static PetscErrorCode SNESSolve_MS(SNES snes)
{
  SNES_MS        *ms = (SNES_MS*)snes->data;
  Vec            X   = snes->vec_sol,F = snes->vec_func;
  PetscReal      fnorm;
  PetscInt       i;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  if (snes->xl || snes->xu || snes->ops->computevariablebounds) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE, "SNES solver %s does not support bounds", ((PetscObject)snes)->type_name);

  ierr = PetscCitationsRegister(SNESCitation,&SNEScite);CHKERRQ(ierr);
  snes->reason = SNES_CONVERGED_ITERATING;
  ierr         = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->iter   = 0;
  snes->norm   = 0.;
  ierr         = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
  if (!snes->vec_func_init_set) {
    ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
  } else snes->vec_func_init_set = PETSC_FALSE;

  if (snes->jacobian) {         /* This method does not require a Jacobian, but it is usually preconditioned by PBJacobi */
    ierr = SNESComputeJacobian(snes,snes->vec_sol,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
  }
  if (ms->norms) {
    ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr); /* fnorm <- ||F||  */
    SNESCheckFunctionNorm(snes,fnorm);
    /* Monitor convergence */
    ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
    snes->iter = 0;
    snes->norm = fnorm;
    ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
    ierr       = SNESLogConvergenceHistory(snes,snes->norm,0);CHKERRQ(ierr);
    ierr       = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);

    /* Test for convergence */
    ierr = (*snes->ops->converged)(snes,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
    if (snes->reason) PetscFunctionReturn(0);
  }

  /* Call general purpose update function */
  if (snes->ops->update) {
    ierr = (*snes->ops->update)(snes,snes->iter);CHKERRQ(ierr);
  }
  for (i = 0; i < snes->max_its; i++) {
    ierr = SNESMSStep_3Sstar(snes,X,F);CHKERRQ(ierr);

    if (i+1 < snes->max_its || ms->norms) {
      ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
    }

    if (ms->norms) {
      ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr); /* fnorm <- ||F||  */
      SNESCheckFunctionNorm(snes,fnorm);

      /* Monitor convergence */
      ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
      snes->iter = i+1;
      snes->norm = fnorm;
      ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
      ierr       = SNESLogConvergenceHistory(snes,snes->norm,0);CHKERRQ(ierr);
      ierr       = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);

      /* Test for convergence */
      ierr = (*snes->ops->converged)(snes,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
      if (snes->reason) PetscFunctionReturn(0);
    }

    /* Call general purpose update function */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }
  }
  if (!snes->reason) snes->reason = SNES_CONVERGED_ITS;
  PetscFunctionReturn(0);
}
Ejemplo n.º 22
0
Archivo: ls.c Proyecto: ziolai/petsc
PetscErrorCode SNESSolve_NEWTONLS(SNES snes)
{
  PetscErrorCode       ierr;
  PetscInt             maxits,i,lits;
  SNESLineSearchReason lssucceed;
  PetscReal            fnorm,gnorm,xnorm,ynorm;
  Vec                  Y,X,F;
  SNESLineSearch       linesearch;
  SNESConvergedReason  reason;

  PetscFunctionBegin;
  if (snes->xl || snes->xu || snes->ops->computevariablebounds) SETERRQ1(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE, "SNES solver %s does not support bounds", ((PetscObject)snes)->type_name);

  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->vec_sol_update;        /* newton step */

  ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->iter = 0;
  snes->norm = 0.0;
  ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
  ierr       = SNESGetLineSearch(snes, &linesearch);CHKERRQ(ierr);

  /* compute the preconditioned function first in the case of left preconditioning with preconditioned function */
  if (snes->pc && snes->pcside == PC_LEFT && snes->functype == SNES_FUNCTION_PRECONDITIONED) {
    ierr = SNESApplyNPC(snes,X,NULL,F);CHKERRQ(ierr);
    ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
    if (reason < 0  && reason != SNES_DIVERGED_MAX_IT) {
      snes->reason = SNES_DIVERGED_INNER;
      PetscFunctionReturn(0);
    }

    ierr = VecNormBegin(F,NORM_2,&fnorm);CHKERRQ(ierr);
    ierr = VecNormEnd(F,NORM_2,&fnorm);CHKERRQ(ierr);
  } else {
    if (!snes->vec_func_init_set) {
      ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
    } else snes->vec_func_init_set = PETSC_FALSE;
  }

  ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr);        /* fnorm <- ||F||  */
  SNESCheckFunctionNorm(snes,fnorm);
  ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->norm = fnorm;
  ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
  ierr       = SNESLogConvergenceHistory(snes,fnorm,0);CHKERRQ(ierr);
  ierr       = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr);

  /* 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++) {

    /* Call general purpose update function */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }

    /* apply the nonlinear preconditioner */
    if (snes->pc) {
      if (snes->pcside == PC_RIGHT) {
        ierr = SNESSetInitialFunction(snes->pc, F);CHKERRQ(ierr);
        ierr = PetscLogEventBegin(SNES_NPCSolve,snes->pc,X,snes->vec_rhs,0);CHKERRQ(ierr);
        ierr = SNESSolve(snes->pc, snes->vec_rhs, X);CHKERRQ(ierr);
        ierr = PetscLogEventEnd(SNES_NPCSolve,snes->pc,X,snes->vec_rhs,0);CHKERRQ(ierr);
        ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
        if (reason < 0  && reason != SNES_DIVERGED_MAX_IT) {
          snes->reason = SNES_DIVERGED_INNER;
          PetscFunctionReturn(0);
        }
        ierr = SNESGetNPCFunction(snes,F,&fnorm);CHKERRQ(ierr);
      } else if (snes->pcside == PC_LEFT && snes->functype == SNES_FUNCTION_UNPRECONDITIONED) {
        ierr = SNESApplyNPC(snes,X,F,F);CHKERRQ(ierr);
        ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
        if (reason < 0  && reason != SNES_DIVERGED_MAX_IT) {
          snes->reason = SNES_DIVERGED_INNER;
          PetscFunctionReturn(0);
        }
      }
    }

    /* Solve J Y = F, where J is Jacobian matrix */
    ierr = SNESComputeJacobian(snes,X,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
    ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
    ierr = KSPSolve(snes->ksp,F,Y);CHKERRQ(ierr);
    SNESCheckKSPSolve(snes);
    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 (PetscLogPrintInfo) {
      ierr = SNESNEWTONLSCheckResidual_Private(snes,snes->jacobian,F,Y);CHKERRQ(ierr);
    }

    /* Compute a (scaled) negative update in the line search routine:
         X <- X - lambda*Y
       and evaluate F = function(X) (depends on the line search).
    */
    gnorm = fnorm;
    ierr  = SNESLineSearchApply(linesearch, X, F, &fnorm, Y);CHKERRQ(ierr);
    ierr  = SNESLineSearchGetReason(linesearch, &lssucceed);CHKERRQ(ierr);
    ierr  = SNESLineSearchGetNorms(linesearch, &xnorm, &fnorm, &ynorm);CHKERRQ(ierr);
    ierr  = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",(double)gnorm,(double)fnorm,(double)ynorm,(int)lssucceed);CHKERRQ(ierr);
    if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break;
    SNESCheckFunctionNorm(snes,fnorm);
    if (lssucceed) {
      if (snes->stol*xnorm > ynorm) {
        snes->reason = SNES_CONVERGED_SNORM_RELATIVE;
        PetscFunctionReturn(0);
      }
      if (++snes->numFailures >= snes->maxFailures) {
        PetscBool ismin;
        snes->reason = SNES_DIVERGED_LINE_SEARCH;
        ierr         = SNESNEWTONLSCheckLocalMin_Private(snes,snes->jacobian,F,fnorm,&ismin);CHKERRQ(ierr);
        if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN;
        break;
      }
    }
    /* Monitor convergence */
    ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
    snes->iter = i+1;
    snes->norm = fnorm;
    ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
    ierr       = SNESLogConvergenceHistory(snes,snes->norm,lits);CHKERRQ(ierr);
    ierr       = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);
    /* Test for convergence */
    ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
    if (snes->reason) break;
  }
  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);
}
Ejemplo n.º 23
0
Archivo: ms.c Proyecto: 00liujj/petsc
static PetscErrorCode SNESSolve_MS(SNES snes)
{
  SNES_MS        *ms = (SNES_MS*)snes->data;
  Vec            X   = snes->vec_sol,F = snes->vec_func;
  PetscReal      fnorm;
  PetscInt       i;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  ierr = PetscCitationsRegister(SNESCitation,&SNEScite);CHKERRQ(ierr);
  snes->reason = SNES_CONVERGED_ITERATING;
  ierr         = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
  snes->iter   = 0;
  snes->norm   = 0.;
  ierr         = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
  if (!snes->vec_func_init_set) {
    ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
    if (snes->domainerror) {
      snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
      PetscFunctionReturn(0);
    }
  } else snes->vec_func_init_set = PETSC_FALSE;

  if (snes->jacobian) {         /* This method does not require a Jacobian, but it is usually preconditioned by PBJacobi */
    ierr = SNESComputeJacobian(snes,snes->vec_sol,snes->jacobian,snes->jacobian_pre);CHKERRQ(ierr);
  }
  if (ms->norms) {
    ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr); /* fnorm <- ||F||  */
    if (PetscIsInfOrNanReal(fnorm)) {
      snes->reason = SNES_DIVERGED_FNORM_NAN;
      PetscFunctionReturn(0);
    }
    /* Monitor convergence */
    ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
    snes->iter = 0;
    snes->norm = fnorm;
    ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
    ierr       = SNESLogConvergenceHistory(snes,snes->norm,0);CHKERRQ(ierr);
    ierr       = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);

    /* Test for convergence */
    ierr = (*snes->ops->converged)(snes,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
    if (snes->reason) PetscFunctionReturn(0);
  }

  /* Call general purpose update function */
  if (snes->ops->update) {
    ierr = (*snes->ops->update)(snes,snes->iter);CHKERRQ(ierr);
  }
  for (i = 0; i < snes->max_its; i++) {
    ierr = SNESMSStep_3Sstar(snes,X,F);CHKERRQ(ierr);

    if (i+1 < snes->max_its || ms->norms) {
      ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
      if (snes->domainerror) {
        snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
        PetscFunctionReturn(0);
      }
    }

    if (ms->norms) {
      ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr); /* fnorm <- ||F||  */
      if (PetscIsInfOrNanReal(fnorm)) {
        snes->reason = SNES_DIVERGED_FNORM_NAN;
        PetscFunctionReturn(0);
      }

      /* Monitor convergence */
      ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
      snes->iter = i+1;
      snes->norm = fnorm;
      ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
      ierr       = SNESLogConvergenceHistory(snes,snes->norm,0);CHKERRQ(ierr);
      ierr       = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);

      /* Test for convergence */
      ierr = (*snes->ops->converged)(snes,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
      if (snes->reason) PetscFunctionReturn(0);
    }

    /* Call general purpose update function */
    if (snes->ops->update) {
      ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr);
    }
  }
  if (!snes->reason) snes->reason = SNES_CONVERGED_ITS;
  PetscFunctionReturn(0);
}
Ejemplo n.º 24
0
/*@C
    SNESUpdateCheckJacobian - Checks each Jacobian computed by the nonlinear solver comparing the users function with a finite difference computation.

   Options Database:
+    -snes_check_jacobian - use this every time SNESSolve() is called
-    -snes_check_jacobian_view -  Display difference between approximate and hand-coded Jacobian

   Level: intermediate

.seealso:  SNESCreate(), SNES, SNESSetType(), SNESNEWTONLS, SNESNEWTONTR, SNESSolve()

@*/
PetscErrorCode SNESUpdateCheckJacobian(SNES snes,PetscInt it)
{
  Mat            A = snes->jacobian,B;
  Vec            x = snes->vec_sol,f = snes->vec_func,f1 = snes->vec_sol_update;
  PetscErrorCode ierr;
  PetscReal      nrm,gnorm;
  PetscErrorCode (*objective)(SNES,Vec,PetscReal*,void*);
  void           *ctx;
  PetscReal      fnorm,f1norm,dnorm;
  PetscInt       m,n,M,N;
  PetscBool      complete_print = PETSC_FALSE;
  void           *functx;
  PetscViewer    viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)snes));

  PetscFunctionBegin;
  ierr = PetscOptionsHasName(((PetscObject)snes)->prefix,"-snes_check_jacobian_view",&complete_print);CHKERRQ(ierr);
  if (A != snes->jacobian_pre) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Cannot check Jacobian with alternative preconditioner");

  ierr = PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);CHKERRQ(ierr);
  ierr = PetscViewerASCIIPrintf(viewer,"      Testing hand-coded Jacobian, if the ratio is O(1.e-8), the hand-coded Jacobian is probably correct.\n");CHKERRQ(ierr);
  if (!complete_print) {
    ierr = PetscViewerASCIIPrintf(viewer,"      Run with -snes_check_jacobian_view [viewer][:filename][:format] to show difference of hand-coded and finite difference Jacobian.\n");CHKERRQ(ierr);
  }

  /* compute both versions of Jacobian */
  ierr = SNESComputeJacobian(snes,x,A,A);CHKERRQ(ierr);

  ierr = MatCreate(PetscObjectComm((PetscObject)A),&B);CHKERRQ(ierr);
  ierr = MatGetSize(A,&M,&N);CHKERRQ(ierr);
  ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
  ierr = MatSetSizes(B,m,n,M,N);CHKERRQ(ierr);
  ierr = MatSetType(B,((PetscObject)A)->type_name);CHKERRQ(ierr);
  ierr = MatSetUp(B);CHKERRQ(ierr);
  ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
  ierr = SNESGetFunction(snes,NULL,NULL,&functx);CHKERRQ(ierr);
  ierr = SNESComputeJacobianDefault(snes,x,B,B,functx);CHKERRQ(ierr);

  if (complete_print) {
    ierr = PetscViewerASCIIPrintf(viewer,"    Finite difference Jacobian\n");CHKERRQ(ierr);
    ierr = MatViewFromOptions(B,((PetscObject)snes)->prefix,"-snes_check_jacobian_view");CHKERRQ(ierr);
  }
  /* compare */
  ierr = MatAYPX(B,-1.0,A,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
  ierr = MatNorm(B,NORM_FROBENIUS,&nrm);CHKERRQ(ierr);
  ierr = MatNorm(A,NORM_FROBENIUS,&gnorm);CHKERRQ(ierr);
  if (complete_print) {
    ierr = PetscViewerASCIIPrintf(viewer,"    Hand-coded Jacobian\n");CHKERRQ(ierr);
    ierr = MatViewFromOptions(A,((PetscObject)snes)->prefix,"-snes_check_jacobian_view");CHKERRQ(ierr);
    ierr = PetscViewerASCIIPrintf(viewer,"    Hand-coded minus finite difference Jacobian\n");CHKERRQ(ierr);
    ierr = MatViewFromOptions(B,((PetscObject)snes)->prefix,"-snes_check_jacobian_view");CHKERRQ(ierr);
  }
  if (!gnorm) gnorm = 1; /* just in case */
  ierr = PetscViewerASCIIPrintf(viewer,"    %g = ||J - Jfd||//J|| %g  = ||J - Jfd||\n",(double)(nrm/gnorm),(double)nrm);CHKERRQ(ierr);

  ierr = SNESGetObjective(snes,&objective,&ctx);CHKERRQ(ierr);
  if (objective) {
    ierr = SNESComputeFunction(snes,x,f);CHKERRQ(ierr);
    ierr = VecNorm(f,NORM_2,&fnorm);CHKERRQ(ierr);
    if (complete_print) {
      ierr = PetscViewerASCIIPrintf(viewer,"    Hand-coded Objective Function \n");CHKERRQ(ierr);
      ierr = VecView(f,viewer);CHKERRQ(ierr);
    }
    ierr = SNESObjectiveComputeFunctionDefaultFD(snes,x,f1,NULL);CHKERRQ(ierr);
    ierr = VecNorm(f1,NORM_2,&f1norm);CHKERRQ(ierr);
    if (complete_print) {
      ierr = PetscViewerASCIIPrintf(viewer,"    Finite-Difference Objective Function\n");CHKERRQ(ierr);
      ierr = VecView(f1,viewer);CHKERRQ(ierr);
    }
    /* compare the two */
    ierr = VecAXPY(f,-1.0,f1);CHKERRQ(ierr);
    ierr = VecNorm(f,NORM_2,&dnorm);CHKERRQ(ierr);
    if (!fnorm) fnorm = 1.;
    ierr = PetscViewerASCIIPrintf(viewer,"    %g = Norm of objective function ratio %g = difference\n",dnorm/fnorm,dnorm);CHKERRQ(ierr);
    if (complete_print) {
      ierr = PetscViewerASCIIPrintf(viewer,"    Difference\n");CHKERRQ(ierr);
      ierr = VecView(f,viewer);CHKERRQ(ierr);
    }
  }
  ierr = PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);CHKERRQ(ierr);

  ierr = MatDestroy(&B);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}
Ejemplo n.º 25
0
void
NonlinearSystem::setupColoringFiniteDifferencedPreconditioner()
{
#ifdef LIBMESH_HAVE_PETSC
  // Make sure that libMesh isn't going to override our preconditioner
  _transient_sys.nonlinear_solver->jacobian = nullptr;

  PetscNonlinearSolver<Number> & petsc_nonlinear_solver =
      dynamic_cast<PetscNonlinearSolver<Number> &>(*_transient_sys.nonlinear_solver);

  // Pointer to underlying PetscMatrix type
  PetscMatrix<Number> * petsc_mat = dynamic_cast<PetscMatrix<Number> *>(_transient_sys.matrix);

#if PETSC_VERSION_LESS_THAN(3, 2, 0)
  // This variable is only needed for PETSC < 3.2.0
  PetscVector<Number> * petsc_vec =
      dynamic_cast<PetscVector<Number> *>(_transient_sys.solution.get());
#endif

  Moose::compute_jacobian(*_transient_sys.current_local_solution, *petsc_mat, _transient_sys);

  if (!petsc_mat)
    mooseError("Could not convert to Petsc matrix.");

  petsc_mat->close();

  PetscErrorCode ierr = 0;
  ISColoring iscoloring;

#if PETSC_VERSION_LESS_THAN(3, 2, 0)
  // PETSc 3.2.x
  ierr = MatGetColoring(petsc_mat->mat(), MATCOLORING_LF, &iscoloring);
  CHKERRABORT(libMesh::COMM_WORLD, ierr);
#elif PETSC_VERSION_LESS_THAN(3, 5, 0)
  // PETSc 3.3.x, 3.4.x
  ierr = MatGetColoring(petsc_mat->mat(), MATCOLORINGLF, &iscoloring);
  CHKERRABORT(_communicator.get(), ierr);
#else
  // PETSc 3.5.x
  MatColoring matcoloring;
  ierr = MatColoringCreate(petsc_mat->mat(), &matcoloring);
  CHKERRABORT(_communicator.get(), ierr);
  ierr = MatColoringSetType(matcoloring, MATCOLORINGLF);
  CHKERRABORT(_communicator.get(), ierr);
  ierr = MatColoringSetFromOptions(matcoloring);
  CHKERRABORT(_communicator.get(), ierr);
  ierr = MatColoringApply(matcoloring, &iscoloring);
  CHKERRABORT(_communicator.get(), ierr);
  ierr = MatColoringDestroy(&matcoloring);
  CHKERRABORT(_communicator.get(), ierr);
#endif

  MatFDColoringCreate(petsc_mat->mat(), iscoloring, &_fdcoloring);
  MatFDColoringSetFromOptions(_fdcoloring);
  MatFDColoringSetFunction(_fdcoloring,
                           (PetscErrorCode(*)(void)) & libMesh::__libmesh_petsc_snes_fd_residual,
                           &petsc_nonlinear_solver);
#if !PETSC_RELEASE_LESS_THAN(3, 5, 0)
  MatFDColoringSetUp(petsc_mat->mat(), iscoloring, _fdcoloring);
#endif
#if PETSC_VERSION_LESS_THAN(3, 4, 0)
  SNESSetJacobian(petsc_nonlinear_solver.snes(),
                  petsc_mat->mat(),
                  petsc_mat->mat(),
                  SNESDefaultComputeJacobianColor,
                  _fdcoloring);
#else
  SNESSetJacobian(petsc_nonlinear_solver.snes(),
                  petsc_mat->mat(),
                  petsc_mat->mat(),
                  SNESComputeJacobianDefaultColor,
                  _fdcoloring);
#endif
#if PETSC_VERSION_LESS_THAN(3, 2, 0)
  Mat my_mat = petsc_mat->mat();
  MatStructure my_struct;

  SNESComputeJacobian(
      petsc_nonlinear_solver.snes(), petsc_vec->vec(), &my_mat, &my_mat, &my_struct);
#endif

#if PETSC_VERSION_LESS_THAN(3, 2, 0)
  ISColoringDestroy(iscoloring);
#else
  // PETSc 3.3.0
  ISColoringDestroy(&iscoloring);
#endif

#endif
}