C++ (Cpp) DSGetDimensions Examples

Example #1

PetscErrorCode EPSGetArbitraryValues(EPS eps,PetscScalar *rr,PetscScalar *ri)
{
  PetscErrorCode ierr;
  PetscInt       i,newi,ld,n,l;
  Vec            xr=eps->work[0],xi=eps->work[1];
  PetscScalar    re,im,*Zr,*Zi,*X;

  PetscFunctionBegin;
  ierr = DSGetLeadingDimension(eps->ds,&ld);CHKERRQ(ierr);
  ierr = DSGetDimensions(eps->ds,&n,NULL,&l,NULL,NULL);CHKERRQ(ierr);
  for (i=l;i<n;i++) {
    re = eps->eigr[i];
    im = eps->eigi[i];
    ierr = STBackTransform(eps->st,1,&re,&im);CHKERRQ(ierr);
    newi = i;
    ierr = DSVectors(eps->ds,DS_MAT_X,&newi,NULL);CHKERRQ(ierr);
    ierr = DSGetArray(eps->ds,DS_MAT_X,&X);CHKERRQ(ierr);
    Zr = X+i*ld;
    if (newi==i+1) Zi = X+newi*ld;
    else Zi = NULL;
    ierr = EPSComputeRitzVector(eps,Zr,Zi,eps->V,xr,xi);CHKERRQ(ierr);
    ierr = DSRestoreArray(eps->ds,DS_MAT_X,&X);CHKERRQ(ierr);
    ierr = (*eps->arbitrary)(re,im,xr,xi,rr+i,ri+i,eps->arbitraryctx);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}

Example #2

PetscErrorCode PEPComputeVectors_Schur(PEP pep)
{
  PetscErrorCode ierr;
  PetscInt       n,i;
  Mat            Z;
  Vec            v;
#if !defined(PETSC_USE_COMPLEX)
  Vec            v1;
  PetscScalar    tmp;
  PetscReal      norm,normi;
#endif

  PetscFunctionBegin;
  ierr = DSGetDimensions(pep->ds,&n,NULL,NULL,NULL,NULL);CHKERRQ(ierr);
  ierr = DSVectors(pep->ds,DS_MAT_X,NULL,NULL);CHKERRQ(ierr);
  ierr = DSGetMat(pep->ds,DS_MAT_X,&Z);CHKERRQ(ierr);
  ierr = BVSetActiveColumns(pep->V,0,n);CHKERRQ(ierr);
  ierr = BVMultInPlace(pep->V,Z,0,n);CHKERRQ(ierr);
  ierr = MatDestroy(&Z);CHKERRQ(ierr);

  /* Fix eigenvectors if balancing was used */
  if ((pep->scale==PEP_SCALE_DIAGONAL || pep->scale==PEP_SCALE_BOTH) && pep->Dr && (pep->refine!=PEP_REFINE_MULTIPLE)) {
    for (i=0;i<n;i++) {
      ierr = BVGetColumn(pep->V,i,&v);CHKERRQ(ierr);
      ierr = VecPointwiseMult(v,v,pep->Dr);CHKERRQ(ierr);
      ierr = BVRestoreColumn(pep->V,i,&v);CHKERRQ(ierr);
    }
  }

  /* normalization */
  for (i=0;i<n;i++) {
#if !defined(PETSC_USE_COMPLEX)
    if (pep->eigi[i] != 0.0) {
      ierr = BVGetColumn(pep->V,i,&v);CHKERRQ(ierr);
      ierr = BVGetColumn(pep->V,i+1,&v1);CHKERRQ(ierr);
      ierr = VecNorm(v,NORM_2,&norm);CHKERRQ(ierr);
      ierr = VecNorm(v1,NORM_2,&normi);CHKERRQ(ierr);
      tmp = 1.0 / SlepcAbsEigenvalue(norm,normi);
      ierr = VecScale(v,tmp);CHKERRQ(ierr);
      ierr = VecScale(v1,tmp);CHKERRQ(ierr);
      ierr = BVRestoreColumn(pep->V,i,&v);CHKERRQ(ierr);
      ierr = BVRestoreColumn(pep->V,i+1,&v1);CHKERRQ(ierr);
      i++;
    } else
#endif
    {
      ierr = BVGetColumn(pep->V,i,&v);CHKERRQ(ierr);
      ierr = VecNormalize(v,NULL);CHKERRQ(ierr);
      ierr = BVRestoreColumn(pep->V,i,&v);CHKERRQ(ierr);
    }
  }
  PetscFunctionReturn(0);
}

Example #3

PetscErrorCode PEPComputeVectors_Indefinite(PEP pep)
{
  PetscErrorCode ierr;
  PetscInt       n,i;
  Mat            Z;
  Vec            v;
#if !defined(PETSC_USE_COMPLEX)
  Vec            v1;
  PetscScalar    tmp;
  PetscReal      norm,normi;
#endif

  PetscFunctionBegin;
  ierr = DSGetDimensions(pep->ds,&n,NULL,NULL,NULL,NULL);CHKERRQ(ierr);
  ierr = DSVectors(pep->ds,DS_MAT_X,NULL,NULL);CHKERRQ(ierr);
  ierr = DSGetMat(pep->ds,DS_MAT_X,&Z);CHKERRQ(ierr);
  ierr = BVSetActiveColumns(pep->V,0,n);CHKERRQ(ierr);
  ierr = BVMultInPlace(pep->V,Z,0,n);CHKERRQ(ierr);
  ierr = MatDestroy(&Z);CHKERRQ(ierr);

  /* normalization */
  for (i=0;i<n;i++) {
#if !defined(PETSC_USE_COMPLEX)
    if (pep->eigi[i] != 0.0) {
      ierr = BVGetColumn(pep->V,i,&v);CHKERRQ(ierr);
      ierr = BVGetColumn(pep->V,i+1,&v1);CHKERRQ(ierr);
      ierr = VecNorm(v,NORM_2,&norm);CHKERRQ(ierr);
      ierr = VecNorm(v1,NORM_2,&normi);CHKERRQ(ierr);
      tmp = 1.0 / SlepcAbsEigenvalue(norm,normi);
      ierr = VecScale(v,tmp);CHKERRQ(ierr);
      ierr = VecScale(v1,tmp);CHKERRQ(ierr);
      ierr = BVRestoreColumn(pep->V,i,&v);CHKERRQ(ierr);
      ierr = BVRestoreColumn(pep->V,i+1,&v1);CHKERRQ(ierr);
      i++;
    } else
#endif
    {
      ierr = BVGetColumn(pep->V,i,&v);CHKERRQ(ierr);
      ierr = VecNormalize(v,NULL);CHKERRQ(ierr);
      ierr = BVRestoreColumn(pep->V,i,&v);CHKERRQ(ierr);
    }
  }
  PetscFunctionReturn(0);
}