示例#1
0
PETSC_EXTERN void PETSC_STDCALL  snesapplynpc_(SNES snes,Vec x,Vec f,Vec y, int *__ierr ){
*__ierr = SNESApplyNPC(
	(SNES)PetscToPointer((snes) ),
	(Vec)PetscToPointer((x) ),
	(Vec)PetscToPointer((f) ),
	(Vec)PetscToPointer((y) ));
}
示例#2
0
文件: snespc.c 项目: lw4992/petsc
PetscErrorCode SNESComputeFunctionDefaultNPC(SNES snes,Vec X,Vec F)
{
/* This is to be used as an argument to SNESMF -- NOT as a "function" */
  SNESConvergedReason reason;
  PetscErrorCode      ierr;

  PetscFunctionBegin;
  if (snes->pc) {
    ierr = SNESApplyNPC(snes,X,NULL,F);CHKERRQ(ierr);
    ierr = SNESGetConvergedReason(snes->pc,&reason);CHKERRQ(ierr);
    if (reason < 0  && reason != SNES_DIVERGED_MAX_IT) {
      ierr = SNESSetFunctionDomainError(snes);CHKERRQ(ierr);
    }
  } else {
    ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}
示例#3
0
PetscErrorCode SNESSolve_NRichardson(SNES snes)
{
    Vec                  X, Y, F;
    PetscReal            xnorm, fnorm, ynorm;
    PetscInt             maxits, i;
    PetscErrorCode       ierr;
    SNESLineSearchReason lsresult;
    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->reason = SNES_CONVERGED_ITERATING;

    maxits = snes->max_its;        /* maximum number of iterations */
    X      = snes->vec_sol;        /* X^n */
    Y      = snes->vec_sol_update; /* \tilde X */
    F      = snes->vec_func;       /* residual vector */

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

    if (snes->pc && 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->functype == SNES_FUNCTION_UNPRECONDITIONED) {
        ierr = SNESApplyNPC(snes,X,F,Y);
        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,Y);
        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);

    /* Call general purpose update function */
    if (snes->ops->update) {
        ierr = (*snes->ops->update)(snes, snes->iter);
        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 = 1; i < maxits+1; i++) {
        ierr = SNESLineSearchApply(snes->linesearch, X, F, &fnorm, Y);
        CHKERRQ(ierr);
        ierr = SNESLineSearchGetReason(snes->linesearch, &lsresult);
        CHKERRQ(ierr);
        ierr = SNESLineSearchGetNorms(snes->linesearch, &xnorm, &fnorm, &ynorm);
        CHKERRQ(ierr);
        if (lsresult) {
            if (++snes->numFailures >= snes->maxFailures) {
                snes->reason = SNES_DIVERGED_LINE_SEARCH;
                break;
            }
        }
        if (snes->nfuncs >= snes->max_funcs) {
            snes->reason = SNES_DIVERGED_FUNCTION_COUNT;
            break;
        }

        /* Monitor convergence */
        ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);
        CHKERRQ(ierr);
        snes->iter = i;
        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,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);
        CHKERRQ(ierr);
        if (snes->reason) break;

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

        if (snes->pc) {
            if (snes->functype == SNES_FUNCTION_PRECONDITIONED) {
                ierr = SNESApplyNPC(snes,X,NULL,Y);
                CHKERRQ(ierr);
                ierr = VecNorm(F,NORM_2,&fnorm);
                CHKERRQ(ierr);
                ierr = VecCopy(Y,F);
                CHKERRQ(ierr);
            } else {
                ierr = SNESApplyNPC(snes,X,F,Y);
                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,Y);
            CHKERRQ(ierr);
        }
    }
    if (i == maxits+1) {
        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);
}
示例#4
0
文件: snesncg.c 项目: 00liujj/petsc
PetscErrorCode SNESSolve_NCG(SNES snes)
{
  SNES_NCG            *ncg = (SNES_NCG*)snes->data;
  Vec                 X,dX,lX,F,dXold;
  PetscReal           fnorm, ynorm, xnorm, beta = 0.0;
  PetscScalar         dXdotdX, dXolddotdXold, dXdotdXold, lXdotdX, lXdotdXold;
  PetscInt            maxits, i;
  PetscErrorCode      ierr;
  PetscBool           lsSuccess = PETSC_TRUE;
  SNESLineSearch      linesearch;
  SNESConvergedReason reason;

  PetscFunctionBegin;
  ierr = PetscCitationsRegister(SNESCitation,&SNEScite);CHKERRQ(ierr);
  snes->reason = SNES_CONVERGED_ITERATING;

  maxits = snes->max_its;            /* maximum number of iterations */
  X      = snes->vec_sol;            /* X^n */
  dXold  = snes->work[0];            /* The previous iterate of X */
  dX     = snes->work[1];            /* the preconditioned direction */
  lX     = snes->vec_sol_update;     /* the conjugate direction */
  F      = snes->vec_func;           /* residual vector */

  ierr = SNESGetLineSearch(snes, &linesearch);CHKERRQ(ierr);

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

  /* compute the initial function and preconditioned update dX */

  if (snes->pc && snes->functype == SNES_FUNCTION_PRECONDITIONED) {
    ierr = SNESApplyNPC(snes,X,NULL,dX);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 = VecCopy(dX,F);CHKERRQ(ierr);
    ierr = VecNorm(F,NORM_2,&fnorm);CHKERRQ(ierr);
  } else {
    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;

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

    ierr = VecCopy(F,dX);CHKERRQ(ierr);
  }
  if (snes->pc) {
    if (snes->functype == SNES_FUNCTION_UNPRECONDITIONED) {
      ierr = SNESApplyNPC(snes,X,F,dX);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 = VecCopy(dX,lX);CHKERRQ(ierr);
  ierr = VecDot(dX, dX, &dXdotdX);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);

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

  /* first update -- just use the (preconditioned) residual direction for the initial conjugate direction */

  for (i = 1; i < maxits + 1; i++) {
    lsSuccess = PETSC_TRUE;
    /* some update types require the old update direction or conjugate direction */
    if (ncg->type != SNES_NCG_FR) {
      ierr = VecCopy(dX, dXold);CHKERRQ(ierr);
    }
    ierr = SNESLineSearchApply(linesearch,X,F,&fnorm,lX);CHKERRQ(ierr);
    ierr = SNESLineSearchGetSuccess(linesearch, &lsSuccess);CHKERRQ(ierr);
    if (!lsSuccess) {
      if (++snes->numFailures >= snes->maxFailures) {
        snes->reason = SNES_DIVERGED_LINE_SEARCH;
        PetscFunctionReturn(0);
      }
    }
    if (snes->nfuncs >= snes->max_funcs) {
      snes->reason = SNES_DIVERGED_FUNCTION_COUNT;
      PetscFunctionReturn(0);
    }
    if (snes->domainerror) {
      snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
      PetscFunctionReturn(0);
    }
    ierr = SNESLineSearchGetNorms(linesearch, &xnorm, &fnorm, &ynorm);CHKERRQ(ierr);
    /* Monitor convergence */
    ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
    snes->iter = i;
    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,xnorm,ynorm,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->pc) {
      if (snes->functype == SNES_FUNCTION_PRECONDITIONED) {
        ierr = SNESApplyNPC(snes,X,NULL,dX);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 = VecCopy(dX,F);CHKERRQ(ierr);
      } else {
        ierr = SNESApplyNPC(snes,X,F,dX);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,dX);CHKERRQ(ierr);
    }

    /* compute the conjugate direction lX = dX + beta*lX with beta = ((dX, dX) / (dX_old, dX_old) (Fletcher-Reeves update)*/
    switch (ncg->type) {
    case SNES_NCG_FR: /* Fletcher-Reeves */
      dXolddotdXold= dXdotdX;
      ierr         = VecDot(dX, dX, &dXdotdX);CHKERRQ(ierr);
      beta         = PetscRealPart(dXdotdX / dXolddotdXold);
      break;
    case SNES_NCG_PRP: /* Polak-Ribiere-Poylak */
      dXolddotdXold= dXdotdX;
      ierr         = VecDotBegin(dX, dX, &dXdotdXold);CHKERRQ(ierr);
      ierr         = VecDotBegin(dXold, dX, &dXdotdXold);CHKERRQ(ierr);
      ierr         = VecDotEnd(dX, dX, &dXdotdX);CHKERRQ(ierr);
      ierr         = VecDotEnd(dXold, dX, &dXdotdXold);CHKERRQ(ierr);
      beta         = PetscRealPart(((dXdotdX - dXdotdXold) / dXolddotdXold));
      if (beta < 0.0) beta = 0.0; /* restart */
      break;
    case SNES_NCG_HS: /* Hestenes-Stiefel */
      ierr = VecDotBegin(dX, dX, &dXdotdX);CHKERRQ(ierr);
      ierr = VecDotBegin(dX, dXold, &dXdotdXold);CHKERRQ(ierr);
      ierr = VecDotBegin(lX, dX, &lXdotdX);CHKERRQ(ierr);
      ierr = VecDotBegin(lX, dXold, &lXdotdXold);CHKERRQ(ierr);
      ierr = VecDotEnd(dX, dX, &dXdotdX);CHKERRQ(ierr);
      ierr = VecDotEnd(dX, dXold, &dXdotdXold);CHKERRQ(ierr);
      ierr = VecDotEnd(lX, dX, &lXdotdX);CHKERRQ(ierr);
      ierr = VecDotEnd(lX, dXold, &lXdotdXold);CHKERRQ(ierr);
      beta = PetscRealPart((dXdotdX - dXdotdXold) / (lXdotdX - lXdotdXold));
      break;
    case SNES_NCG_DY: /* Dai-Yuan */
      ierr = VecDotBegin(dX, dX, &dXdotdX);CHKERRQ(ierr);
      ierr = VecDotBegin(lX, dX, &lXdotdX);CHKERRQ(ierr);
      ierr = VecDotBegin(lX, dXold, &lXdotdXold);CHKERRQ(ierr);
      ierr = VecDotEnd(dX, dX, &dXdotdX);CHKERRQ(ierr);
      ierr = VecDotEnd(lX, dX, &lXdotdX);CHKERRQ(ierr);
      ierr = VecDotEnd(lX, dXold, &lXdotdXold);CHKERRQ(ierr);
      beta = PetscRealPart(dXdotdX / (lXdotdXold - lXdotdX));CHKERRQ(ierr);
      break;
    case SNES_NCG_CD: /* Conjugate Descent */
      ierr = VecDotBegin(dX, dX, &dXdotdX);CHKERRQ(ierr);
      ierr = VecDotBegin(lX, dXold, &lXdotdXold);CHKERRQ(ierr);
      ierr = VecDotEnd(dX, dX, &dXdotdX);CHKERRQ(ierr);
      ierr = VecDotEnd(lX, dXold, &lXdotdXold);CHKERRQ(ierr);
      beta = PetscRealPart(dXdotdX / lXdotdXold);CHKERRQ(ierr);
      break;
    }
    if (ncg->monitor) {
      ierr = PetscViewerASCIIPrintf(ncg->monitor, "beta = %e\n", (double)beta);CHKERRQ(ierr);
    }
    ierr = VecAYPX(lX, beta, dX);CHKERRQ(ierr);
  }
  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);
}
示例#5
0
PetscErrorCode SNESSolve_Anderson(SNES snes)
{
  SNES_NGMRES         *ngmres = (SNES_NGMRES*) snes->data;
  /* present solution, residual, and preconditioned residual */
  Vec                 X,F,B,D;
  /* candidate linear combination answers */
  Vec                 XA,FA,XM,FM;

  /* coefficients and RHS to the minimization problem */
  PetscReal           fnorm,fMnorm,fAnorm;
  PetscReal           xnorm,ynorm;
  PetscReal           dnorm,dminnorm=0.0,fminnorm;
  PetscInt            restart_count=0;
  PetscInt            k,k_restart,l,ivec;
  PetscBool           selectRestart;
  SNESConvergedReason reason;
  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);
  /* variable initialization */
  snes->reason = SNES_CONVERGED_ITERATING;
  X            = snes->vec_sol;
  F            = snes->vec_func;
  B            = snes->vec_rhs;
  XA           = snes->vec_sol_update;
  FA           = snes->work[0];
  D            = snes->work[1];

  /* work for the line search */
  XM = snes->work[3];
  FM = snes->work[4];

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

  /* initialization */

  /* r = F(x) */

  if (snes->pc && snes->pcside == PC_LEFT) {
    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);
  }
  fminnorm = 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);
  ierr       = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
  if (snes->reason) PetscFunctionReturn(0);

  k_restart = 0;
  l         = 0;
  ivec      = 0;
  for (k=1; k < snes->max_its+1; k++) {
    /* select which vector of the stored subspace will be updated */
    if (snes->pc && snes->pcside == PC_RIGHT) {
      ierr = VecCopy(X,XM);CHKERRQ(ierr);
      ierr = SNESSetInitialFunction(snes->pc,F);CHKERRQ(ierr);

      ierr = PetscLogEventBegin(SNES_NPCSolve,snes->pc,XM,B,0);CHKERRQ(ierr);
      ierr = SNESSolve(snes->pc,B,XM);CHKERRQ(ierr);
      ierr = PetscLogEventEnd(SNES_NPCSolve,snes->pc,XM,B,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,FM,&fMnorm);CHKERRQ(ierr);
      if (ngmres->andersonBeta != 1.0) {
        VecAXPBY(XM,(1.0 - ngmres->andersonBeta),ngmres->andersonBeta,X);CHKERRQ(ierr);
      }
    } else {
      ierr   = VecCopy(F,FM);CHKERRQ(ierr);
      ierr   = VecCopy(X,XM);CHKERRQ(ierr);
      ierr   = VecAXPY(XM,-ngmres->andersonBeta,FM);CHKERRQ(ierr);
      fMnorm = fnorm;
    }

    ierr = SNESNGMRESFormCombinedSolution_Private(snes,ivec,l,XM,FM,fMnorm,X,XA,FA);CHKERRQ(ierr);
    ivec = k_restart % ngmres->msize;
    if (ngmres->restart_type == SNES_NGMRES_RESTART_DIFFERENCE) {
      ierr = SNESNGMRESNorms_Private(snes,l,X,F,XM,FM,XA,FA,D,&dnorm,&dminnorm,NULL,NULL,NULL,&xnorm,&fAnorm,&ynorm);CHKERRQ(ierr);
      ierr = SNESNGMRESSelectRestart_Private(snes,l,fMnorm,fnorm,dnorm,fminnorm,dminnorm,&selectRestart);CHKERRQ(ierr);
      /* if the restart conditions persist for more than restart_it iterations, restart. */
      if (selectRestart) restart_count++;
      else restart_count = 0;
    } else if (ngmres->restart_type == SNES_NGMRES_RESTART_PERIODIC) {
      ierr = SNESNGMRESNorms_Private(snes,l,X,F,XM,FM,XA,FA,D,NULL,NULL,NULL,NULL,NULL,&xnorm,&fAnorm,&ynorm);CHKERRQ(ierr);
      if (k_restart > ngmres->restart_periodic) {
        if (ngmres->monitor) ierr = PetscViewerASCIIPrintf(ngmres->monitor,"periodic restart after %D iterations\n",k_restart);CHKERRQ(ierr);
        restart_count = ngmres->restart_it;
      }
    } else {
      ierr = SNESNGMRESNorms_Private(snes,l,X,F,XM,FM,XA,FA,D,NULL,NULL,NULL,NULL,NULL,&xnorm,&fAnorm,&ynorm);CHKERRQ(ierr);
    }
    /* restart after restart conditions have persisted for a fixed number of iterations */
    if (restart_count >= ngmres->restart_it) {
      if (ngmres->monitor) {
        ierr = PetscViewerASCIIPrintf(ngmres->monitor,"Restarted at iteration %d\n",k_restart);CHKERRQ(ierr);
      }
      restart_count = 0;
      k_restart     = 0;
      l             = 0;
      ivec          = 0;
    } else {
      if (l < ngmres->msize) l++;
      k_restart++;
      ierr = SNESNGMRESUpdateSubspace_Private(snes,ivec,l,FM,fnorm,XM);CHKERRQ(ierr);
    }

    fnorm = fAnorm;
    if (fminnorm > fnorm) fminnorm = fnorm;

    ierr = VecCopy(XA,X);CHKERRQ(ierr);
    ierr = VecCopy(FA,F);CHKERRQ(ierr);

    ierr       = PetscObjectSAWsTakeAccess((PetscObject)snes);CHKERRQ(ierr);
    snes->iter = k;
    snes->norm = fnorm;
    ierr       = PetscObjectSAWsGrantAccess((PetscObject)snes);CHKERRQ(ierr);
    ierr       = SNESLogConvergenceHistory(snes,snes->norm,snes->iter);CHKERRQ(ierr);
    ierr       = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr);
    ierr       = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr);
    if (snes->reason) PetscFunctionReturn(0);
  }
  snes->reason = SNES_DIVERGED_MAX_IT;
  PetscFunctionReturn(0);
}
示例#6
0
文件: ls.c 项目: 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);
}
示例#7
0
文件: qn.c 项目: pombredanne/petsc
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);
}
示例#8
0
PetscErrorCode SNESNGMRESFormCombinedSolution_Private(SNES snes,PetscInt ivec,PetscInt l,Vec XM,Vec FM,PetscReal fMnorm,Vec X,Vec XA,Vec FA)
{
  SNES_NGMRES    *ngmres = (SNES_NGMRES*) snes->data;
  PetscInt       i,j;
  Vec            *Fdot      = ngmres->Fdot;
  Vec            *Xdot      = ngmres->Xdot;
  PetscScalar    *beta      = ngmres->beta;
  PetscScalar    *xi        = ngmres->xi;
  PetscScalar    alph_total = 0.;
  PetscErrorCode ierr;
  PetscReal      nu;
  Vec            Y = snes->work[2];
  PetscBool      changed_y,changed_w;

  PetscFunctionBegin;
  nu = fMnorm*fMnorm;

  /* construct the right hand side and xi factors */
  if (l > 0) {
    ierr = VecMDotBegin(FM,l,Fdot,xi);CHKERRQ(ierr);
    ierr = VecMDotBegin(Fdot[ivec],l,Fdot,beta);CHKERRQ(ierr);
    ierr = VecMDotEnd(FM,l,Fdot,xi);CHKERRQ(ierr);
    ierr = VecMDotEnd(Fdot[ivec],l,Fdot,beta);CHKERRQ(ierr);
    for (i = 0; i < l; i++) {
      Q(i,ivec) = beta[i];
      Q(ivec,i) = beta[i];
    }
  } else {
    Q(0,0) = ngmres->fnorms[ivec]*ngmres->fnorms[ivec];
  }

  for (i = 0; i < l; i++) beta[i] = nu - xi[i];

  /* construct h */
  for (j = 0; j < l; j++) {
    for (i = 0; i < l; i++) {
      H(i,j) = Q(i,j)-xi[i]-xi[j]+nu;
    }
  }
  if (l == 1) {
    /* simply set alpha[0] = beta[0] / H[0, 0] */
    if (H(0,0) != 0.) beta[0] = beta[0]/H(0,0);
    else beta[0] = 0.;
  } else {
#if defined(PETSC_MISSING_LAPACK_GELSS)
    SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_SUP,"NGMRES with LS requires the LAPACK GELSS routine.");
#else
    ierr          = PetscBLASIntCast(l,&ngmres->m);CHKERRQ(ierr);
    ierr          = PetscBLASIntCast(l,&ngmres->n);CHKERRQ(ierr);
    ngmres->info  = 0;
    ngmres->rcond = -1.;
    ierr          = PetscFPTrapPush(PETSC_FP_TRAP_OFF);CHKERRQ(ierr);
#if defined(PETSC_USE_COMPLEX)
    PetscStackCallBLAS("LAPACKgelss",LAPACKgelss_(&ngmres->m,&ngmres->n,&ngmres->nrhs,ngmres->h,&ngmres->lda,ngmres->beta,&ngmres->ldb,ngmres->s,&ngmres->rcond,&ngmres->rank,ngmres->work,&ngmres->lwork,ngmres->rwork,&ngmres->info));
#else
    PetscStackCallBLAS("LAPACKgelss",LAPACKgelss_(&ngmres->m,&ngmres->n,&ngmres->nrhs,ngmres->h,&ngmres->lda,ngmres->beta,&ngmres->ldb,ngmres->s,&ngmres->rcond,&ngmres->rank,ngmres->work,&ngmres->lwork,&ngmres->info));
#endif
    ierr = PetscFPTrapPop();CHKERRQ(ierr);
    if (ngmres->info < 0) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_LIB,"Bad argument to GELSS");
    if (ngmres->info > 0) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_LIB,"SVD failed to converge");
#endif
  }
  for (i=0; i<l; i++) {
    if (PetscIsInfOrNanScalar(beta[i])) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_LIB,"SVD generated inconsistent output");
  }
  alph_total = 0.;
  for (i = 0; i < l; i++) alph_total += beta[i];

  ierr = VecCopy(XM,XA);CHKERRQ(ierr);
  ierr = VecScale(XA,1.-alph_total);CHKERRQ(ierr);
  ierr = VecMAXPY(XA,l,beta,Xdot);CHKERRQ(ierr);
  /* check the validity of the step */
  ierr = VecCopy(XA,Y);CHKERRQ(ierr);
  ierr = VecAXPY(Y,-1.0,X);CHKERRQ(ierr);
  ierr = SNESLineSearchPostCheck(snes->linesearch,X,Y,XA,&changed_y,&changed_w);CHKERRQ(ierr);
  if (!ngmres->approxfunc) {
    if (snes->pc && snes->pcside == PC_LEFT) {
      ierr = SNESApplyNPC(snes,XA,NULL,FA);CHKERRQ(ierr);
    } else {
      ierr =SNESComputeFunction(snes,XA,FA);CHKERRQ(ierr);
    }
  } else {
    ierr = VecCopy(FM,FA);CHKERRQ(ierr);
    ierr = VecScale(FA,1.-alph_total);CHKERRQ(ierr);
    ierr = VecMAXPY(FA,l,beta,Fdot);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}