Date: 2024-12-02T08:58:02+00:00

Actual source code: bvbasic.c
slepc-3.22.2 2024-12-02
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      1: /*
      2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
      4:    Copyright (c) 2002-, Universitat Politecnica de Valencia, Spain

      6:    This file is part of SLEPc.
      7:    SLEPc is distributed under a 2-clause BSD license (see LICENSE).
      8:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      9: */
     10: /*
     11:    Basic BV routines
     12: */

     14: #include <slepc/private/bvimpl.h>

     16: PetscBool         BVRegisterAllCalled = PETSC_FALSE;
     17: PetscFunctionList BVList = NULL;

     19: /*@
     20:    BVSetType - Selects the type for the BV object.

     22:    Logically Collective

     24:    Input Parameters:
     25: +  bv   - the basis vectors context
     26: -  type - a known type

     28:    Options Database Key:
     29: .  -bv_type <type> - Sets BV type

     31:    Level: intermediate

     33: .seealso: BVGetType()
     34: @*/
     35: PetscErrorCode BVSetType(BV bv,BVType type)
     36: {
     37:   PetscErrorCode (*r)(BV);
     38:   PetscBool      match;

     40:   PetscFunctionBegin;
     42:   PetscAssertPointer(type,2);

     44:   PetscCall(PetscObjectTypeCompare((PetscObject)bv,type,&match));
     45:   if (match) PetscFunctionReturn(PETSC_SUCCESS);
     46:   PetscCall(PetscStrcmp(type,BVTENSOR,&match));
     47:   PetscCheck(!match,PetscObjectComm((PetscObject)bv),PETSC_ERR_ORDER,"Use BVCreateTensor() to create a BV of type tensor");

     49:   PetscCall(PetscFunctionListFind(BVList,type,&r));
     50:   PetscCheck(r,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_UNKNOWN_TYPE,"Unable to find requested BV type %s",type);

     52:   PetscTryTypeMethod(bv,destroy);
     53:   PetscCall(PetscMemzero(bv->ops,sizeof(struct _BVOps)));

     55:   PetscCall(PetscObjectChangeTypeName((PetscObject)bv,type));
     56:   if (bv->n < 0 && bv->N < 0) {
     57:     bv->ops->create = r;
     58:   } else {
     59:     PetscCall(PetscLogEventBegin(BV_Create,bv,0,0,0));
     60:     PetscCall((*r)(bv));
     61:     PetscCall(PetscLogEventEnd(BV_Create,bv,0,0,0));
     62:   }
     63:   PetscFunctionReturn(PETSC_SUCCESS);
     64: }

     66: /*@
     67:    BVGetType - Gets the BV type name (as a string) from the BV context.

     69:    Not Collective

     71:    Input Parameter:
     72: .  bv - the basis vectors context

     74:    Output Parameter:
     75: .  type - name of the type of basis vectors

     77:    Level: intermediate

     79: .seealso: BVSetType()
     80: @*/
     81: PetscErrorCode BVGetType(BV bv,BVType *type)
     82: {
     83:   PetscFunctionBegin;
     85:   PetscAssertPointer(type,2);
     86:   *type = ((PetscObject)bv)->type_name;
     87:   PetscFunctionReturn(PETSC_SUCCESS);
     88: }

     90: /*@
     91:    BVSetSizes - Sets the local and global sizes, and the number of columns.

     93:    Collective

     95:    Input Parameters:
     96: +  bv - the basis vectors
     97: .  n  - the local size (or PETSC_DECIDE to have it set)
     98: .  N  - the global size (or PETSC_DECIDE)
     99: -  m  - the number of columns

    101:    Notes:
    102:    n and N cannot be both PETSC_DECIDE.
    103:    If one processor calls this with N of PETSC_DECIDE then all processors must,
    104:    otherwise the program will hang.

    106:    Level: beginner

    108: .seealso: BVSetSizesFromVec(), BVGetSizes(), BVResize()
    109: @*/
    110: PetscErrorCode BVSetSizes(BV bv,PetscInt n,PetscInt N,PetscInt m)
    111: {
    112:   PetscInt       ma;
    113:   PetscMPIInt    size;

    115:   PetscFunctionBegin;
    119:   PetscCheck(N<0 || n<=N,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Local size %" PetscInt_FMT " cannot be larger than global size %" PetscInt_FMT,n,N);
    120:   PetscCheck(m>0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Number of columns %" PetscInt_FMT " must be positive",m);
    121:   PetscCheck((bv->n<0 && bv->N<0) || (bv->n==n && bv->N==N),PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Cannot change/reset vector sizes to %" PetscInt_FMT " local %" PetscInt_FMT " global after previously setting them to %" PetscInt_FMT " local %" PetscInt_FMT " global",n,N,bv->n,bv->N);
    122:   PetscCheck(bv->m<=0 || bv->m==m,PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Cannot change the number of columns to %" PetscInt_FMT " after previously setting it to %" PetscInt_FMT "; use BVResize()",m,bv->m);
    123:   PetscCheck(!bv->map,PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Vector layout was already defined by a previous call to BVSetSizes/FromVec");
    124:   bv->n = n;
    125:   bv->N = N;
    126:   bv->m = m;
    127:   bv->k = m;
    128:   /* create layout and get actual dimensions */
    129:   PetscCall(PetscLayoutCreate(PetscObjectComm((PetscObject)bv),&bv->map));
    130:   PetscCall(PetscLayoutSetSize(bv->map,bv->N));
    131:   PetscCall(PetscLayoutSetLocalSize(bv->map,bv->n));
    132:   PetscCall(PetscLayoutSetUp(bv->map));
    133:   PetscCall(PetscLayoutGetSize(bv->map,&bv->N));
    134:   PetscCall(PetscLayoutGetLocalSize(bv->map,&bv->n));
    135:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)bv),&size));
    136:   PetscCall(BVSetVecType(bv,(size==1)?VECSEQ:VECMPI));
    137:   if (bv->matrix) {  /* check compatible dimensions of user-provided matrix */
    138:     PetscCall(MatGetLocalSize(bv->matrix,&ma,NULL));
    139:     PetscCheck(bv->n==ma,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Local dimension %" PetscInt_FMT " does not match that of matrix given at BVSetMatrix %" PetscInt_FMT,bv->n,ma);
    140:   }
    141:   if (bv->ops->create) {
    142:     PetscCall(PetscLogEventBegin(BV_Create,bv,0,0,0));
    143:     PetscUseTypeMethod(bv,create);
    144:     PetscCall(PetscLogEventEnd(BV_Create,bv,0,0,0));
    145:     bv->ops->create = NULL;
    146:     bv->defersfo = PETSC_FALSE;
    147:   }
    148:   PetscFunctionReturn(PETSC_SUCCESS);
    149: }

    151: /*@
    152:    BVSetSizesFromVec - Sets the local and global sizes, and the number of columns.
    153:    Local and global sizes are specified indirectly by passing a template vector.

    155:    Collective

    157:    Input Parameters:
    158: +  bv - the basis vectors
    159: .  t  - the template vector
    160: -  m  - the number of columns

    162:    Level: beginner

    164: .seealso: BVSetSizes(), BVGetSizes(), BVResize()
    165: @*/
    166: PetscErrorCode BVSetSizesFromVec(BV bv,Vec t,PetscInt m)
    167: {
    168:   PetscInt       ma;
    169:   PetscLayout    map;
    170:   VecType        vtype;

    172:   PetscFunctionBegin;
    175:   PetscCheckSameComm(bv,1,t,2);
    177:   PetscCheck(m>0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Number of columns %" PetscInt_FMT " must be positive",m);
    178:   PetscCheck(!bv->map,PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Vector layout was already defined by a previous call to BVSetSizes/FromVec");
    179:   PetscCall(VecGetType(t,&vtype));
    180:   PetscCall(BVSetVecType(bv,vtype));
    181:   PetscCall(VecGetLayout(t,&map));
    182:   PetscCall(PetscLayoutReference(map,&bv->map));
    183:   PetscCall(VecGetSize(t,&bv->N));
    184:   PetscCall(VecGetLocalSize(t,&bv->n));
    185:   if (bv->matrix) {  /* check compatible dimensions of user-provided matrix */
    186:     PetscCall(MatGetLocalSize(bv->matrix,&ma,NULL));
    187:     PetscCheck(bv->n==ma,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Local dimension %" PetscInt_FMT " does not match that of matrix given at BVSetMatrix %" PetscInt_FMT,bv->n,ma);
    188:   }
    189:   bv->m = m;
    190:   bv->k = m;
    191:   if (bv->ops->create) {
    192:     PetscUseTypeMethod(bv,create);
    193:     bv->ops->create = NULL;
    194:     bv->defersfo = PETSC_FALSE;
    195:   }
    196:   PetscFunctionReturn(PETSC_SUCCESS);
    197: }

    199: /*@
    200:    BVGetSizes - Returns the local and global sizes, and the number of columns.

    202:    Not Collective

    204:    Input Parameter:
    205: .  bv - the basis vectors

    207:    Output Parameters:
    208: +  n  - the local size
    209: .  N  - the global size
    210: -  m  - the number of columns

    212:    Note:
    213:    Normal usage requires that bv has already been given its sizes, otherwise
    214:    the call fails. However, this function can also be used to determine if
    215:    a BV object has been initialized completely (sizes and type). For this,
    216:    call with n=NULL and N=NULL, then a return value of m=0 indicates that
    217:    the BV object is not ready for use yet.

    219:    Level: beginner

    221: .seealso: BVSetSizes(), BVSetSizesFromVec()
    222: @*/
    223: PetscErrorCode BVGetSizes(BV bv,PetscInt *n,PetscInt *N,PetscInt *m)
    224: {
    225:   PetscFunctionBegin;
    226:   if (!bv) {
    227:     if (m && !n && !N) *m = 0;
    228:     PetscFunctionReturn(PETSC_SUCCESS);
    229:   }
    231:   if (n || N) BVCheckSizes(bv,1);
    232:   if (n) *n = bv->n;
    233:   if (N) *N = bv->N;
    234:   if (m) *m = bv->m;
    235:   if (m && !n && !N && !((PetscObject)bv)->type_name) *m = 0;
    236:   PetscFunctionReturn(PETSC_SUCCESS);
    237: }

    239: /*@
    240:    BVSetNumConstraints - Set the number of constraints.

    242:    Logically Collective

    244:    Input Parameters:
    245: +  V  - basis vectors
    246: -  nc - number of constraints

    248:    Notes:
    249:    This function sets the number of constraints to nc and marks all remaining
    250:    columns as regular. Normal user would call BVInsertConstraints() instead.

    252:    If nc is smaller than the previously set value, then some of the constraints
    253:    are discarded. In particular, using nc=0 removes all constraints preserving
    254:    the content of regular columns.

    256:    Level: developer

    258: .seealso: BVInsertConstraints()
    259: @*/
    260: PetscErrorCode BVSetNumConstraints(BV V,PetscInt nc)
    261: {
    262:   PetscInt       total,diff,i;
    263:   Vec            x,y;

    265:   PetscFunctionBegin;
    268:   PetscCheck(nc>=0,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_OUTOFRANGE,"Number of constraints (given %" PetscInt_FMT ") cannot be negative",nc);
    270:   BVCheckSizes(V,1);
    271:   PetscCheck(V->ci[0]==-V->nc-1 && V->ci[1]==-V->nc-1,PetscObjectComm((PetscObject)V),PETSC_ERR_SUP,"Cannot call BVSetNumConstraints after BVGetColumn");

    273:   diff = nc-V->nc;
    274:   if (!diff) PetscFunctionReturn(PETSC_SUCCESS);
    275:   total = V->nc+V->m;
    276:   PetscCheck(total-nc>0,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_OUTOFRANGE,"Not enough columns for the given nc value");
    277:   if (diff<0) {  /* lessen constraints, shift contents of BV */
    278:     for (i=0;i<V->m;i++) {
    279:       PetscCall(BVGetColumn(V,i,&x));
    280:       PetscCall(BVGetColumn(V,i+diff,&y));
    281:       PetscCall(VecCopy(x,y));
    282:       PetscCall(BVRestoreColumn(V,i,&x));
    283:       PetscCall(BVRestoreColumn(V,i+diff,&y));
    284:     }
    285:   }
    286:   V->nc = nc;
    287:   V->ci[0] = -V->nc-1;
    288:   V->ci[1] = -V->nc-1;
    289:   V->m = total-nc;
    290:   V->l = PetscMin(V->l,V->m);
    291:   V->k = PetscMin(V->k,V->m);
    292:   PetscCall(PetscObjectStateIncrease((PetscObject)V));
    293:   PetscFunctionReturn(PETSC_SUCCESS);
    294: }

    296: /*@
    297:    BVGetNumConstraints - Returns the number of constraints.

    299:    Not Collective

    301:    Input Parameter:
    302: .  bv - the basis vectors

    304:    Output Parameters:
    305: .  nc - the number of constraints

    307:    Level: advanced

    309: .seealso: BVGetSizes(), BVInsertConstraints()
    310: @*/
    311: PetscErrorCode BVGetNumConstraints(BV bv,PetscInt *nc)
    312: {
    313:   PetscFunctionBegin;
    315:   PetscAssertPointer(nc,2);
    316:   *nc = bv->nc;
    317:   PetscFunctionReturn(PETSC_SUCCESS);
    318: }

    320: /*@
    321:    BVResize - Change the number of columns.

    323:    Collective

    325:    Input Parameters:
    326: +  bv   - the basis vectors
    327: .  m    - the new number of columns
    328: -  copy - a flag indicating whether current values should be kept

    330:    Note:
    331:    Internal storage is reallocated. If the copy flag is set to true, then
    332:    the contents are copied to the leading part of the new space.

    334:    Level: advanced

    336: .seealso: BVSetSizes(), BVSetSizesFromVec()
    337: @*/
    338: PetscErrorCode BVResize(BV bv,PetscInt m,PetscBool copy)
    339: {
    340:   PetscScalar       *array;
    341:   const PetscScalar *omega;
    342:   Vec               v;

    344:   PetscFunctionBegin;
    349:   PetscCheck(m>0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Number of columns %" PetscInt_FMT " must be positive",m);
    350:   PetscCheck(!bv->nc || bv->issplit,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Cannot resize a BV with constraints");
    351:   if (bv->m == m) PetscFunctionReturn(PETSC_SUCCESS);
    352:   BVCheckOp(bv,1,resize);

    354:   PetscCall(PetscLogEventBegin(BV_Create,bv,0,0,0));
    355:   PetscUseTypeMethod(bv,resize,m,copy);
    356:   PetscCall(VecDestroy(&bv->buffer));
    357:   PetscCall(BVDestroy(&bv->cached));
    358:   PetscCall(PetscFree2(bv->h,bv->c));
    359:   if (bv->omega) {
    360:     if (bv->cuda) {
    361: #if defined(PETSC_HAVE_CUDA)
    362:       PetscCall(VecCreateSeqCUDA(PETSC_COMM_SELF,m,&v));
    363: #else
    364:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_PLIB,"Something wrong happened");
    365: #endif
    366:     } else if (bv->hip) {
    367: #if defined(PETSC_HAVE_HIP)
    368:       PetscCall(VecCreateSeqHIP(PETSC_COMM_SELF,m,&v));
    369: #else
    370:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_PLIB,"Something wrong happened");
    371: #endif
    372:     } else PetscCall(VecCreateSeq(PETSC_COMM_SELF,m,&v));
    373:     if (copy) {
    374:       PetscCall(VecGetArray(v,&array));
    375:       PetscCall(VecGetArrayRead(bv->omega,&omega));
    376:       PetscCall(PetscArraycpy(array,omega,PetscMin(m,bv->m)));
    377:       PetscCall(VecRestoreArrayRead(bv->omega,&omega));
    378:       PetscCall(VecRestoreArray(v,&array));
    379:     } else PetscCall(VecSet(v,1.0));
    380:     PetscCall(VecDestroy(&bv->omega));
    381:     bv->omega = v;
    382:   }
    383:   bv->m = m;
    384:   bv->k = PetscMin(bv->k,m);
    385:   bv->l = PetscMin(bv->l,m);
    386:   PetscCall(PetscLogEventEnd(BV_Create,bv,0,0,0));
    387:   PetscCall(PetscObjectStateIncrease((PetscObject)bv));
    388:   PetscFunctionReturn(PETSC_SUCCESS);
    389: }

    391: /*@
    392:    BVSetActiveColumns - Specify the columns that will be involved in operations.

    394:    Logically Collective

    396:    Input Parameters:
    397: +  bv - the basis vectors context
    398: .  l  - number of leading columns
    399: -  k  - number of active columns

    401:    Notes:
    402:    In operations such as BVMult() or BVDot(), only the first k columns are
    403:    considered. This is useful when the BV is filled from left to right, so
    404:    the last m-k columns do not have relevant information.

    406:    Also in operations such as BVMult() or BVDot(), the first l columns are
    407:    normally not included in the computation. See the manpage of each
    408:    operation.

    410:    In orthogonalization operations, the first l columns are treated
    411:    differently, they participate in the orthogonalization but the computed
    412:    coefficients are not stored.

    414:    Use PETSC_CURRENT to leave any of the values unchanged. Use PETSC_DETERMINE
    415:    to set l to the minimum value (0) and k to the maximum (m).

    417:    Level: intermediate

    419: .seealso: BVGetActiveColumns(), BVSetSizes()
    420: @*/
    421: PetscErrorCode BVSetActiveColumns(BV bv,PetscInt l,PetscInt k)
    422: {
    423:   PetscFunctionBegin;
    427:   BVCheckSizes(bv,1);
    428:   if (PetscUnlikely(k == PETSC_DETERMINE)) {
    429:     bv->k = bv->m;
    430:   } else if (k != PETSC_CURRENT) {
    431:     PetscCheck(k>=0 && k<=bv->m,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of k (%" PetscInt_FMT "). Must be between 0 and m (%" PetscInt_FMT ")",k,bv->m);
    432:     bv->k = k;
    433:   }
    434:   if (PetscUnlikely(l == PETSC_DETERMINE)) {
    435:     bv->l = 0;
    436:   } else if (l != PETSC_CURRENT) {
    437:     PetscCheck(l>=0 && l<=bv->k,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of l (%" PetscInt_FMT "). Must be between 0 and k (%" PetscInt_FMT ")",l,bv->k);
    438:     bv->l = l;
    439:   }
    440:   PetscFunctionReturn(PETSC_SUCCESS);
    441: }

    443: /*@
    444:    BVGetActiveColumns - Returns the current active dimensions.

    446:    Not Collective

    448:    Input Parameter:
    449: .  bv - the basis vectors context

    451:    Output Parameters:
    452: +  l  - number of leading columns
    453: -  k  - number of active columns

    455:    Level: intermediate

    457: .seealso: BVSetActiveColumns()
    458: @*/
    459: PetscErrorCode BVGetActiveColumns(BV bv,PetscInt *l,PetscInt *k)
    460: {
    461:   PetscFunctionBegin;
    463:   if (l) *l = bv->l;
    464:   if (k) *k = bv->k;
    465:   PetscFunctionReturn(PETSC_SUCCESS);
    466: }

    468: /*@
    469:    BVSetMatrix - Specifies the inner product to be used in orthogonalization.

    471:    Collective

    473:    Input Parameters:
    474: +  bv    - the basis vectors context
    475: .  B     - a symmetric matrix (may be NULL)
    476: -  indef - a flag indicating if the matrix is indefinite

    478:    Notes:
    479:    This is used to specify a non-standard inner product, whose matrix
    480:    representation is given by B. Then, all inner products required during
    481:    orthogonalization are computed as (x,y)_B=y^H*B*x rather than the
    482:    standard form (x,y)=y^H*x.

    484:    Matrix B must be real symmetric (or complex Hermitian). A genuine inner
    485:    product requires that B is also positive (semi-)definite. However, we
    486:    also allow for an indefinite B (setting indef=PETSC_TRUE), in which
    487:    case the orthogonalization uses an indefinite inner product.

    489:    This affects operations BVDot(), BVNorm(), BVOrthogonalize(), and variants.

    491:    Setting B=NULL has the same effect as if the identity matrix was passed.

    493:    Level: advanced

    495: .seealso: BVGetMatrix(), BVDot(), BVNorm(), BVOrthogonalize(), BVSetDefiniteTolerance()
    496: @*/
    497: PetscErrorCode BVSetMatrix(BV bv,Mat B,PetscBool indef)
    498: {
    499:   PetscInt       m,n;

    501:   PetscFunctionBegin;
    504:   if (B!=bv->matrix || (B && ((PetscObject)B)->id!=((PetscObject)bv->matrix)->id) || indef!=bv->indef) {
    505:     if (B) {
    507:       PetscCall(MatGetLocalSize(B,&m,&n));
    508:       PetscCheck(m==n,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_SIZ,"Matrix must be square");
    509:       PetscCheck(!bv->m || bv->n==n,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_INCOMP,"Mismatching local dimension BV %" PetscInt_FMT ", Mat %" PetscInt_FMT,bv->n,n);
    510:     }
    511:     if (B) PetscCall(PetscObjectReference((PetscObject)B));
    512:     PetscCall(MatDestroy(&bv->matrix));
    513:     bv->matrix = B;
    514:     bv->indef  = indef;
    515:     PetscCall(PetscObjectStateIncrease((PetscObject)bv));
    516:     if (bv->Bx) PetscCall(PetscObjectStateIncrease((PetscObject)bv->Bx));
    517:     if (bv->cached) PetscCall(PetscObjectStateIncrease((PetscObject)bv->cached));
    518:   }
    519:   PetscFunctionReturn(PETSC_SUCCESS);
    520: }

    522: /*@
    523:    BVGetMatrix - Retrieves the matrix representation of the inner product.

    525:    Not Collective

    527:    Input Parameter:
    528: .  bv    - the basis vectors context

    530:    Output Parameters:
    531: +  B     - the matrix of the inner product (may be NULL)
    532: -  indef - the flag indicating if the matrix is indefinite

    534:    Level: advanced

    536: .seealso: BVSetMatrix()
    537: @*/
    538: PetscErrorCode BVGetMatrix(BV bv,Mat *B,PetscBool *indef)
    539: {
    540:   PetscFunctionBegin;
    542:   if (B)     *B     = bv->matrix;
    543:   if (indef) *indef = bv->indef;
    544:   PetscFunctionReturn(PETSC_SUCCESS);
    545: }

    547: /*@
    548:    BVApplyMatrix - Multiplies a vector by the matrix representation of the
    549:    inner product.

    551:    Neighbor-wise Collective

    553:    Input Parameters:
    554: +  bv - the basis vectors context
    555: -  x  - the vector

    557:    Output Parameter:
    558: .  y  - the result

    560:    Note:
    561:    If no matrix was specified this function copies the vector.

    563:    Level: advanced

    565: .seealso: BVSetMatrix(), BVApplyMatrixBV()
    566: @*/
    567: PetscErrorCode BVApplyMatrix(BV bv,Vec x,Vec y)
    568: {
    569:   PetscFunctionBegin;
    573:   if (bv->matrix) {
    574:     PetscCall(BV_IPMatMult(bv,x));
    575:     PetscCall(VecCopy(bv->Bx,y));
    576:   } else PetscCall(VecCopy(x,y));
    577:   PetscFunctionReturn(PETSC_SUCCESS);
    578: }

    580: /*@
    581:    BVApplyMatrixBV - Multiplies the BV vectors by the matrix representation
    582:    of the inner product.

    584:    Neighbor-wise Collective

    586:    Input Parameter:
    587: .  X - the basis vectors context

    589:    Output Parameter:
    590: .  Y - the basis vectors to store the result (optional)

    592:    Note:
    593:    This function computes Y = B*X, where B is the matrix given with
    594:    BVSetMatrix(). This operation is computed as in BVMatMult().
    595:    If no matrix was specified, then it just copies Y = X.

    597:    If no Y is given, the result is stored internally in the cached BV.

    599:    Level: developer

    601: .seealso: BVSetMatrix(), BVApplyMatrix(), BVMatMult(), BVGetCachedBV()
    602: @*/
    603: PetscErrorCode BVApplyMatrixBV(BV X,BV Y)
    604: {
    605:   PetscFunctionBegin;
    607:   if (Y) {
    609:     if (X->matrix) PetscCall(BVMatMult(X,X->matrix,Y));
    610:     else PetscCall(BVCopy(X,Y));
    611:   } else PetscCall(BV_IPMatMultBV(X));
    612:   PetscFunctionReturn(PETSC_SUCCESS);
    613: }

    615: /*@
    616:    BVSetSignature - Sets the signature matrix to be used in orthogonalization.

    618:    Logically Collective

    620:    Input Parameters:
    621: +  bv    - the basis vectors context
    622: -  omega - a vector representing the diagonal of the signature matrix

    624:    Note:
    625:    The signature matrix Omega = V'*B*V is relevant only for an indefinite B.

    627:    Level: developer

    629: .seealso: BVSetMatrix(), BVGetSignature()
    630: @*/
    631: PetscErrorCode BVSetSignature(BV bv,Vec omega)
    632: {
    633:   PetscInt          i,n;
    634:   const PetscScalar *pomega;
    635:   PetscScalar       *intern;

    637:   PetscFunctionBegin;
    639:   BVCheckSizes(bv,1);

    643:   PetscCall(VecGetSize(omega,&n));
    644:   PetscCheck(n==bv->k,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_SIZ,"Vec argument has %" PetscInt_FMT " elements, should be %" PetscInt_FMT,n,bv->k);
    645:   PetscCall(BV_AllocateSignature(bv));
    646:   if (bv->indef) {
    647:     PetscCall(VecGetArrayRead(omega,&pomega));
    648:     PetscCall(VecGetArray(bv->omega,&intern));
    649:     for (i=0;i<n;i++) intern[bv->nc+i] = pomega[i];
    650:     PetscCall(VecRestoreArray(bv->omega,&intern));
    651:     PetscCall(VecRestoreArrayRead(omega,&pomega));
    652:   } else PetscCall(PetscInfo(bv,"Ignoring signature because BV is not indefinite\n"));
    653:   PetscCall(PetscObjectStateIncrease((PetscObject)bv));
    654:   PetscFunctionReturn(PETSC_SUCCESS);
    655: }

    657: /*@
    658:    BVGetSignature - Retrieves the signature matrix from last orthogonalization.

    660:    Not Collective

    662:    Input Parameter:
    663: .  bv    - the basis vectors context

    665:    Output Parameter:
    666: .  omega - a vector representing the diagonal of the signature matrix

    668:    Note:
    669:    The signature matrix Omega = V'*B*V is relevant only for an indefinite B.

    671:    Level: developer

    673: .seealso: BVSetMatrix(), BVSetSignature()
    674: @*/
    675: PetscErrorCode BVGetSignature(BV bv,Vec omega)
    676: {
    677:   PetscInt          i,n;
    678:   PetscScalar       *pomega;
    679:   const PetscScalar *intern;

    681:   PetscFunctionBegin;
    683:   BVCheckSizes(bv,1);

    687:   PetscCall(VecGetSize(omega,&n));
    688:   PetscCheck(n==bv->k,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_SIZ,"Vec argument has %" PetscInt_FMT " elements, should be %" PetscInt_FMT,n,bv->k);
    689:   if (bv->indef && bv->omega) {
    690:     PetscCall(VecGetArray(omega,&pomega));
    691:     PetscCall(VecGetArrayRead(bv->omega,&intern));
    692:     for (i=0;i<n;i++) pomega[i] = intern[bv->nc+i];
    693:     PetscCall(VecRestoreArrayRead(bv->omega,&intern));
    694:     PetscCall(VecRestoreArray(omega,&pomega));
    695:   } else PetscCall(VecSet(omega,1.0));
    696:   PetscFunctionReturn(PETSC_SUCCESS);
    697: }

    699: /*@
    700:    BVSetBufferVec - Attach a vector object to be used as buffer space for
    701:    several operations.

    703:    Collective

    705:    Input Parameters:
    706: +  bv     - the basis vectors context)
    707: -  buffer - the vector

    709:    Notes:
    710:    Use BVGetBufferVec() to retrieve the vector (for example, to free it
    711:    at the end of the computations).

    713:    The vector must be sequential of length (nc+m)*m, where m is the number
    714:    of columns of bv and nc is the number of constraints.

    716:    Level: developer

    718: .seealso: BVGetBufferVec(), BVSetSizes(), BVGetNumConstraints()
    719: @*/
    720: PetscErrorCode BVSetBufferVec(BV bv,Vec buffer)
    721: {
    722:   PetscInt       ld,n;
    723:   PetscMPIInt    size;

    725:   PetscFunctionBegin;
    728:   BVCheckSizes(bv,1);
    729:   PetscCall(VecGetSize(buffer,&n));
    730:   ld = bv->m+bv->nc;
    731:   PetscCheck(n==ld*bv->m,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_SIZ,"Buffer size must be %" PetscInt_FMT,ld*bv->m);
    732:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)buffer),&size));
    733:   PetscCheck(size==1,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Buffer must be a sequential vector");

    735:   PetscCall(PetscObjectReference((PetscObject)buffer));
    736:   PetscCall(VecDestroy(&bv->buffer));
    737:   bv->buffer = buffer;
    738:   PetscFunctionReturn(PETSC_SUCCESS);
    739: }

    741: /*@
    742:    BVGetBufferVec - Obtain the buffer vector associated with the BV object.

    744:    Collective

    746:    Input Parameters:
    747: .  bv - the basis vectors context

    749:    Output Parameter:
    750: .  buffer - vector

    752:    Notes:
    753:    The vector is created if not available previously. It is a sequential vector
    754:    of length (nc+m)*m, where m is the number of columns of bv and nc is the number
    755:    of constraints.

    757:    Developer Notes:
    758:    The buffer vector is viewed as a column-major matrix with leading dimension
    759:    ld=nc+m, and m columns at most. In the most common usage, it has the structure
    760: .vb
    761:       | | C |
    762:       |s|---|
    763:       | | H |
    764: .ve
    765:    where H is an upper Hessenberg matrix of order m x (m-1), C contains coefficients
    766:    related to orthogonalization against constraints (first nc rows), and s is the
    767:    first column that contains scratch values computed during Gram-Schmidt
    768:    orthogonalization. In particular, BVDotColumn() and BVMultColumn() use s to
    769:    store the coefficients.

    771:    Level: developer

    773: .seealso: BVSetBufferVec(), BVSetSizes(), BVGetNumConstraints(), BVDotColumn(), BVMultColumn()
    774: @*/
    775: PetscErrorCode BVGetBufferVec(BV bv,Vec *buffer)
    776: {
    777:   PetscInt       ld;

    779:   PetscFunctionBegin;
    781:   PetscAssertPointer(buffer,2);
    782:   BVCheckSizes(bv,1);
    783:   if (!bv->buffer) {
    784:     ld = bv->m+bv->nc;
    785:     PetscCall(VecCreate(PETSC_COMM_SELF,&bv->buffer));
    786:     PetscCall(VecSetSizes(bv->buffer,PETSC_DECIDE,ld*bv->m));
    787:     PetscCall(VecSetType(bv->buffer,bv->vtype));
    788:   }
    789:   *buffer = bv->buffer;
    790:   PetscFunctionReturn(PETSC_SUCCESS);
    791: }

    793: /*@
    794:    BVSetRandomContext - Sets the PetscRandom object associated with the BV,
    795:    to be used in operations that need random numbers.

    797:    Collective

    799:    Input Parameters:
    800: +  bv   - the basis vectors context
    801: -  rand - the random number generator context

    803:    Level: advanced

    805: .seealso: BVGetRandomContext(), BVSetRandom(), BVSetRandomNormal(), BVSetRandomColumn(), BVSetRandomCond()
    806: @*/
    807: PetscErrorCode BVSetRandomContext(BV bv,PetscRandom rand)
    808: {
    809:   PetscFunctionBegin;
    812:   PetscCheckSameComm(bv,1,rand,2);
    813:   PetscCall(PetscObjectReference((PetscObject)rand));
    814:   PetscCall(PetscRandomDestroy(&bv->rand));
    815:   bv->rand = rand;
    816:   PetscFunctionReturn(PETSC_SUCCESS);
    817: }

    819: /*@
    820:    BVGetRandomContext - Gets the PetscRandom object associated with the BV.

    822:    Collective

    824:    Input Parameter:
    825: .  bv - the basis vectors context

    827:    Output Parameter:
    828: .  rand - the random number generator context

    830:    Level: advanced

    832: .seealso: BVSetRandomContext(), BVSetRandom(), BVSetRandomNormal(), BVSetRandomColumn(), BVSetRandomCond()
    833: @*/
    834: PetscErrorCode BVGetRandomContext(BV bv,PetscRandom* rand)
    835: {
    836:   PetscFunctionBegin;
    838:   PetscAssertPointer(rand,2);
    839:   if (!bv->rand) {
    840:     PetscCall(PetscRandomCreate(PetscObjectComm((PetscObject)bv),&bv->rand));
    841:     if (bv->cuda) PetscCall(PetscRandomSetType(bv->rand,PETSCCURAND));
    842:     if (bv->sfocalled) PetscCall(PetscRandomSetFromOptions(bv->rand));
    843:     if (bv->rrandom) {
    844:       PetscCall(PetscRandomSetSeed(bv->rand,0x12345678));
    845:       PetscCall(PetscRandomSeed(bv->rand));
    846:     }
    847:   }
    848:   *rand = bv->rand;
    849:   PetscFunctionReturn(PETSC_SUCCESS);
    850: }

    852: /*@
    853:    BVSetFromOptions - Sets BV options from the options database.

    855:    Collective

    857:    Input Parameter:
    858: .  bv - the basis vectors context

    860:    Level: beginner

    862: .seealso: BVSetOptionsPrefix()
    863: @*/
    864: PetscErrorCode BVSetFromOptions(BV bv)
    865: {
    866:   char               type[256];
    867:   PetscBool          flg1,flg2,flg3,flg4;
    868:   PetscReal          r;
    869:   BVOrthogType       otype;
    870:   BVOrthogRefineType orefine;
    871:   BVOrthogBlockType  oblock;

    873:   PetscFunctionBegin;
    875:   PetscCall(BVRegisterAll());
    876:   PetscObjectOptionsBegin((PetscObject)bv);
    877:     PetscCall(PetscOptionsFList("-bv_type","Basis Vectors type","BVSetType",BVList,(char*)(((PetscObject)bv)->type_name?((PetscObject)bv)->type_name:BVMAT),type,sizeof(type),&flg1));
    878:     if (flg1) PetscCall(BVSetType(bv,type));
    879:     else if (!((PetscObject)bv)->type_name) PetscCall(BVSetType(bv,BVMAT));

    881:     otype = bv->orthog_type;
    882:     PetscCall(PetscOptionsEnum("-bv_orthog_type","Orthogonalization method","BVSetOrthogonalization",BVOrthogTypes,(PetscEnum)otype,(PetscEnum*)&otype,&flg1));
    883:     orefine = bv->orthog_ref;
    884:     PetscCall(PetscOptionsEnum("-bv_orthog_refine","Iterative refinement mode during orthogonalization","BVSetOrthogonalization",BVOrthogRefineTypes,(PetscEnum)orefine,(PetscEnum*)&orefine,&flg2));
    885:     r = bv->orthog_eta;
    886:     PetscCall(PetscOptionsReal("-bv_orthog_eta","Parameter of iterative refinement during orthogonalization","BVSetOrthogonalization",r,&r,&flg3));
    887:     oblock = bv->orthog_block;
    888:     PetscCall(PetscOptionsEnum("-bv_orthog_block","Block orthogonalization method","BVSetOrthogonalization",BVOrthogBlockTypes,(PetscEnum)oblock,(PetscEnum*)&oblock,&flg4));
    889:     if (flg1 || flg2 || flg3 || flg4) PetscCall(BVSetOrthogonalization(bv,otype,orefine,r,oblock));

    891:     PetscCall(PetscOptionsEnum("-bv_matmult","Method for BVMatMult","BVSetMatMultMethod",BVMatMultTypes,(PetscEnum)bv->vmm,(PetscEnum*)&bv->vmm,NULL));

    893:     PetscCall(PetscOptionsReal("-bv_definite_tol","Tolerance for checking a definite inner product","BVSetDefiniteTolerance",r,&r,&flg1));
    894:     if (flg1) PetscCall(BVSetDefiniteTolerance(bv,r));

    896:     /* undocumented option to generate random vectors that are independent of the number of processes */
    897:     PetscCall(PetscOptionsGetBool(NULL,NULL,"-bv_reproducible_random",&bv->rrandom,NULL));

    899:     if (bv->ops->create) bv->defersfo = PETSC_TRUE;   /* defer call to setfromoptions */
    900:     else PetscTryTypeMethod(bv,setfromoptions,PetscOptionsObject);
    901:     PetscCall(PetscObjectProcessOptionsHandlers((PetscObject)bv,PetscOptionsObject));
    902:   PetscOptionsEnd();
    903:   bv->sfocalled = PETSC_TRUE;
    904:   PetscFunctionReturn(PETSC_SUCCESS);
    905: }

    907: /*@
    908:    BVSetOrthogonalization - Specifies the method used for the orthogonalization of
    909:    vectors (classical or modified Gram-Schmidt with or without refinement), and
    910:    for the block-orthogonalization (simultaneous orthogonalization of a set of
    911:    vectors).

    913:    Logically Collective

    915:    Input Parameters:
    916: +  bv     - the basis vectors context
    917: .  type   - the method of vector orthogonalization
    918: .  refine - type of refinement
    919: .  eta    - parameter for selective refinement
    920: -  block  - the method of block orthogonalization

    922:    Options Database Keys:
    923: +  -bv_orthog_type <type> - Where <type> is cgs for Classical Gram-Schmidt orthogonalization
    924:                          (default) or mgs for Modified Gram-Schmidt orthogonalization
    925: .  -bv_orthog_refine <ref> - Where <ref> is one of never, ifneeded (default) or always
    926: .  -bv_orthog_eta <eta> -  For setting the value of eta
    927: -  -bv_orthog_block <block> - Where <block> is the block-orthogonalization method

    929:    Notes:
    930:    The default settings work well for most problems.

    932:    The parameter eta should be a real value between 0 and 1, that is used only when
    933:    the refinement type is "ifneeded". Use PETSC_DETERMINE to set a reasonable
    934:    default value. Use PETSC_CURRENT to leave the current value unchanged.

    936:    When using several processors, MGS is likely to result in bad scalability.

    938:    If the method set for block orthogonalization is GS, then the computation
    939:    is done column by column with the vector orthogonalization.

    941:    Level: advanced

    943: .seealso: BVOrthogonalizeColumn(), BVGetOrthogonalization(), BVOrthogType, BVOrthogRefineType, BVOrthogBlockType
    944: @*/
    945: PetscErrorCode BVSetOrthogonalization(BV bv,BVOrthogType type,BVOrthogRefineType refine,PetscReal eta,BVOrthogBlockType block)
    946: {
    947:   PetscFunctionBegin;
    953:   switch (type) {
    954:     case BV_ORTHOG_CGS:
    955:     case BV_ORTHOG_MGS:
    956:       bv->orthog_type = type;
    957:       break;
    958:     default:
    959:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Unknown orthogonalization type");
    960:   }
    961:   switch (refine) {
    962:     case BV_ORTHOG_REFINE_NEVER:
    963:     case BV_ORTHOG_REFINE_IFNEEDED:
    964:     case BV_ORTHOG_REFINE_ALWAYS:
    965:       bv->orthog_ref = refine;
    966:       break;
    967:     default:
    968:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Unknown refinement type");
    969:   }
    970:   if (eta == (PetscReal)PETSC_DETERMINE) {
    971:     bv->orthog_eta = 0.7071;
    972:   } else if (eta != (PetscReal)PETSC_CURRENT) {
    973:     PetscCheck(eta>0.0 && eta<=1.0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Invalid eta value");
    974:     bv->orthog_eta = eta;
    975:   }
    976:   switch (block) {
    977:     case BV_ORTHOG_BLOCK_GS:
    978:     case BV_ORTHOG_BLOCK_CHOL:
    979:     case BV_ORTHOG_BLOCK_TSQR:
    980:     case BV_ORTHOG_BLOCK_TSQRCHOL:
    981:     case BV_ORTHOG_BLOCK_SVQB:
    982:       bv->orthog_block = block;
    983:       break;
    984:     default:
    985:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Unknown block orthogonalization type");
    986:   }
    987:   PetscFunctionReturn(PETSC_SUCCESS);
    988: }

    990: /*@
    991:    BVGetOrthogonalization - Gets the orthogonalization settings from the BV object.

    993:    Not Collective

    995:    Input Parameter:
    996: .  bv - basis vectors context

    998:    Output Parameters:
    999: +  type   - the method of vector orthogonalization
    1000: .  refine - type of refinement
    1001: .  eta    - parameter for selective refinement
    1002: -  block  - the method of block orthogonalization

    1004:    Level: advanced

    1006: .seealso: BVOrthogonalizeColumn(), BVSetOrthogonalization(), BVOrthogType, BVOrthogRefineType, BVOrthogBlockType
    1007: @*/
    1008: PetscErrorCode BVGetOrthogonalization(BV bv,BVOrthogType *type,BVOrthogRefineType *refine,PetscReal *eta,BVOrthogBlockType *block)
    1009: {
    1010:   PetscFunctionBegin;
    1012:   if (type)   *type   = bv->orthog_type;
    1013:   if (refine) *refine = bv->orthog_ref;
    1014:   if (eta)    *eta    = bv->orthog_eta;
    1015:   if (block)  *block  = bv->orthog_block;
    1016:   PetscFunctionReturn(PETSC_SUCCESS);
    1017: }

    1019: /*@
    1020:    BVSetMatMultMethod - Specifies the method used for the BVMatMult() operation.

    1022:    Logically Collective

    1024:    Input Parameters:
    1025: +  bv     - the basis vectors context
    1026: -  method - the method for the BVMatMult() operation

    1028:    Options Database Keys:
    1029: .  -bv_matmult <meth> - choose one of the methods: vecs, mat

    1031:    Notes:
    1032:    Allowed values are
    1033: +  BV_MATMULT_VECS - perform a matrix-vector multiply per each column
    1034: .  BV_MATMULT_MAT - carry out a Mat-Mat product with a dense matrix
    1035: -  BV_MATMULT_MAT_SAVE - this case is deprecated

    1037:    The default is BV_MATMULT_MAT except in the case of BVVECS.

    1039:    Level: advanced

    1041: .seealso: BVMatMult(), BVGetMatMultMethod(), BVMatMultType
    1042: @*/
    1043: PetscErrorCode BVSetMatMultMethod(BV bv,BVMatMultType method)
    1044: {
    1045:   PetscFunctionBegin;
    1048:   switch (method) {
    1049:     case BV_MATMULT_VECS:
    1050:     case BV_MATMULT_MAT:
    1051:       bv->vmm = method;
    1052:       break;
    1053:     case BV_MATMULT_MAT_SAVE:
    1054:       PetscCall(PetscInfo(bv,"BV_MATMULT_MAT_SAVE is deprecated, using BV_MATMULT_MAT\n"));
    1055:       bv->vmm = BV_MATMULT_MAT;
    1056:       break;
    1057:     default:
    1058:       SETERRQ(PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Unknown matmult method");
    1059:   }
    1060:   PetscFunctionReturn(PETSC_SUCCESS);
    1061: }

    1063: /*@
    1064:    BVGetMatMultMethod - Gets the method used for the BVMatMult() operation.

    1066:    Not Collective

    1068:    Input Parameter:
    1069: .  bv - basis vectors context

    1071:    Output Parameter:
    1072: .  method - the method for the BVMatMult() operation

    1074:    Level: advanced

    1076: .seealso: BVMatMult(), BVSetMatMultMethod(), BVMatMultType
    1077: @*/
    1078: PetscErrorCode BVGetMatMultMethod(BV bv,BVMatMultType *method)
    1079: {
    1080:   PetscFunctionBegin;
    1082:   PetscAssertPointer(method,2);
    1083:   *method = bv->vmm;
    1084:   PetscFunctionReturn(PETSC_SUCCESS);
    1085: }

    1087: /*@
    1088:    BVGetColumn - Returns a Vec object that contains the entries of the
    1089:    requested column of the basis vectors object.

    1091:    Logically Collective

    1093:    Input Parameters:
    1094: +  bv - the basis vectors context
    1095: -  j  - the index of the requested column

    1097:    Output Parameter:
    1098: .  v  - vector containing the jth column

    1100:    Notes:
    1101:    The returned Vec must be seen as a reference (not a copy) of the BV
    1102:    column, that is, modifying the Vec will change the BV entries as well.

    1104:    The returned Vec must not be destroyed. BVRestoreColumn() must be
    1105:    called when it is no longer needed. At most, two columns can be fetched,
    1106:    that is, this function can only be called twice before the corresponding
    1107:    BVRestoreColumn() is invoked.

    1109:    A negative index j selects the i-th constraint, where i=-j. Constraints
    1110:    should not be modified.

    1112:    Level: beginner

    1114: .seealso: BVRestoreColumn(), BVInsertConstraints()
    1115: @*/
    1116: PetscErrorCode BVGetColumn(BV bv,PetscInt j,Vec *v)
    1117: {
    1118:   PetscInt       l;

    1120:   PetscFunctionBegin;
    1123:   BVCheckSizes(bv,1);
    1124:   BVCheckOp(bv,1,getcolumn);
    1126:   PetscCheck(j>=0 || -j<=bv->nc,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"You requested constraint %" PetscInt_FMT " but only %" PetscInt_FMT " are available",-j,bv->nc);
    1127:   PetscCheck(j<bv->m,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"You requested column %" PetscInt_FMT " but only %" PetscInt_FMT " are available",j,bv->m);
    1128:   PetscCheck(j!=bv->ci[0] && j!=bv->ci[1],PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Column %" PetscInt_FMT " already fetched in a previous call to BVGetColumn",j);
    1129:   l = BVAvailableVec;
    1130:   PetscCheck(l!=-1,PetscObjectComm((PetscObject)bv),PETSC_ERR_SUP,"Too many requested columns; you must call BVRestoreColumn for one of the previously fetched columns");
    1131:   PetscUseTypeMethod(bv,getcolumn,j,v);
    1132:   bv->ci[l] = j;
    1133:   PetscCall(VecGetState(bv->cv[l],&bv->st[l]));
    1134:   PetscCall(PetscObjectGetId((PetscObject)bv->cv[l],&bv->id[l]));
    1135:   *v = bv->cv[l];
    1136:   PetscFunctionReturn(PETSC_SUCCESS);
    1137: }

    1139: /*@
    1140:    BVRestoreColumn - Restore a column obtained with BVGetColumn().

    1142:    Logically Collective

    1144:    Input Parameters:
    1145: +  bv - the basis vectors context
    1146: .  j  - the index of the column
    1147: -  v  - vector obtained with BVGetColumn()

    1149:    Note:
    1150:    The arguments must match the corresponding call to BVGetColumn().

    1152:    Level: beginner

    1154: .seealso: BVGetColumn()
    1155: @*/
    1156: PetscErrorCode BVRestoreColumn(BV bv,PetscInt j,Vec *v)
    1157: {
    1158:   PetscObjectId    id;
    1159:   PetscObjectState st;
    1160:   PetscInt         l;

    1162:   PetscFunctionBegin;
    1165:   BVCheckSizes(bv,1);
    1167:   PetscAssertPointer(v,3);
    1169:   PetscCheck(j>=0 || -j<=bv->nc,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"You requested constraint %" PetscInt_FMT " but only %" PetscInt_FMT " are available",-j,bv->nc);
    1170:   PetscCheck(j<bv->m,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"You requested column %" PetscInt_FMT " but only %" PetscInt_FMT " are available",j,bv->m);
    1171:   PetscCheck(j==bv->ci[0] || j==bv->ci[1],PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Column %" PetscInt_FMT " has not been fetched with a call to BVGetColumn",j);
    1172:   l = (j==bv->ci[0])? 0: 1;
    1173:   PetscCall(PetscObjectGetId((PetscObject)*v,&id));
    1174:   PetscCheck(id==bv->id[l],PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Argument 3 is not the same Vec that was obtained with BVGetColumn");
    1175:   PetscCall(VecGetState(*v,&st));
    1176:   if (st!=bv->st[l]) PetscCall(PetscObjectStateIncrease((PetscObject)bv));
    1177:   PetscUseTypeMethod(bv,restorecolumn,j,v);
    1178:   bv->ci[l] = -bv->nc-1;
    1179:   bv->st[l] = -1;
    1180:   bv->id[l] = 0;
    1181:   *v = NULL;
    1182:   PetscFunctionReturn(PETSC_SUCCESS);
    1183: }

    1185: /*@C
    1186:    BVGetArray - Returns a pointer to a contiguous array that contains this
    1187:    processor's portion of the BV data.

    1189:    Logically Collective

    1191:    Input Parameters:
    1192: .  bv - the basis vectors context

    1194:    Output Parameter:
    1195: .  a  - location to put pointer to the array

    1197:    Notes:
    1198:    BVRestoreArray() must be called when access to the array is no longer needed.
    1199:    This operation may imply a data copy, for BV types that do not store
    1200:    data contiguously in memory.

    1202:    The pointer will normally point to the first entry of the first column,
    1203:    but if the BV has constraints then these go before the regular columns.

    1205:    Note that for manipulating the pointer to the BV array, one must take into
    1206:    account the leading dimension, which might be different from the local
    1207:    number of rows, see BVGetLeadingDimension().

    1209:    Use BVGetArrayRead() for read-only access.

    1211:    Level: advanced

    1213: .seealso: BVRestoreArray(), BVInsertConstraints(), BVGetLeadingDimension(), BVGetArrayRead()
    1214: @*/
    1215: PetscErrorCode BVGetArray(BV bv,PetscScalar **a)
    1216: {
    1217:   PetscFunctionBegin;
    1220:   BVCheckSizes(bv,1);
    1221:   BVCheckOp(bv,1,getarray);
    1222:   PetscUseTypeMethod(bv,getarray,a);
    1223:   PetscFunctionReturn(PETSC_SUCCESS);
    1224: }

    1226: /*@C
    1227:    BVRestoreArray - Restore the BV object after BVGetArray() has been called.

    1229:    Logically Collective

    1231:    Input Parameters:
    1232: +  bv - the basis vectors context
    1233: -  a  - location of pointer to array obtained from BVGetArray()

    1235:    Note:
    1236:    This operation may imply a data copy, for BV types that do not store
    1237:    data contiguously in memory.

    1239:    Level: advanced

    1241: .seealso: BVGetColumn()
    1242: @*/
    1243: PetscErrorCode BVRestoreArray(BV bv,PetscScalar **a)
    1244: {
    1245:   PetscFunctionBegin;
    1248:   BVCheckSizes(bv,1);
    1249:   PetscTryTypeMethod(bv,restorearray,a);
    1250:   if (a) *a = NULL;
    1251:   PetscCall(PetscObjectStateIncrease((PetscObject)bv));
    1252:   PetscFunctionReturn(PETSC_SUCCESS);
    1253: }

    1255: /*@C
    1256:    BVGetArrayRead - Returns a read-only pointer to a contiguous array that
    1257:    contains this processor's portion of the BV data.

    1259:    Not Collective

    1261:    Input Parameters:
    1262: .  bv - the basis vectors context

    1264:    Output Parameter:
    1265: .  a  - location to put pointer to the array

    1267:    Notes:
    1268:    BVRestoreArrayRead() must be called when access to the array is no
    1269:    longer needed. This operation may imply a data copy, for BV types that
    1270:    do not store data contiguously in memory.

    1272:    The pointer will normally point to the first entry of the first column,
    1273:    but if the BV has constraints then these go before the regular columns.

    1275:    Level: advanced

    1277: .seealso: BVRestoreArray(), BVInsertConstraints(), BVGetLeadingDimension(), BVGetArray()
    1278: @*/
    1279: PetscErrorCode BVGetArrayRead(BV bv,const PetscScalar **a)
    1280: {
    1281:   PetscFunctionBegin;
    1284:   BVCheckSizes(bv,1);
    1285:   BVCheckOp(bv,1,getarrayread);
    1286:   PetscUseTypeMethod(bv,getarrayread,a);
    1287:   PetscFunctionReturn(PETSC_SUCCESS);
    1288: }

    1290: /*@C
    1291:    BVRestoreArrayRead - Restore the BV object after BVGetArrayRead() has
    1292:    been called.

    1294:    Not Collective

    1296:    Input Parameters:
    1297: +  bv - the basis vectors context
    1298: -  a  - location of pointer to array obtained from BVGetArrayRead()

    1300:    Level: advanced

    1302: .seealso: BVGetColumn()
    1303: @*/
    1304: PetscErrorCode BVRestoreArrayRead(BV bv,const PetscScalar **a)
    1305: {
    1306:   PetscFunctionBegin;
    1309:   BVCheckSizes(bv,1);
    1310:   PetscTryTypeMethod(bv,restorearrayread,a);
    1311:   if (a) *a = NULL;
    1312:   PetscFunctionReturn(PETSC_SUCCESS);
    1313: }

    1315: /*@
    1316:    BVCreateVec - Creates a new Vec object with the same type and dimensions
    1317:    as the columns of the basis vectors object.

    1319:    Collective

    1321:    Input Parameter:
    1322: .  bv - the basis vectors context

    1324:    Output Parameter:
    1325: .  v  - the new vector

    1327:    Note:
    1328:    The user is responsible of destroying the returned vector.

    1330:    Level: beginner

    1332: .seealso: BVCreateMat(), BVCreateVecEmpty()
    1333: @*/
    1334: PetscErrorCode BVCreateVec(BV bv,Vec *v)
    1335: {
    1336:   PetscFunctionBegin;
    1338:   BVCheckSizes(bv,1);
    1339:   PetscAssertPointer(v,2);
    1340:   PetscCall(VecCreate(PetscObjectComm((PetscObject)bv),v));
    1341:   PetscCall(VecSetLayout(*v,bv->map));
    1342:   PetscCall(VecSetType(*v,bv->vtype));
    1343:   PetscCall(VecSetUp(*v));
    1344:   PetscFunctionReturn(PETSC_SUCCESS);
    1345: }

    1347: /*@
    1348:    BVCreateVecEmpty - Creates a new Vec object with the same type and dimensions
    1349:    as the columns of the basis vectors object, but without internal array.

    1351:    Collective

    1353:    Input Parameter:
    1354: .  bv - the basis vectors context

    1356:    Output Parameter:
    1357: .  v  - the new vector

    1359:    Note:
    1360:    This works as BVCreateVec(), but the new vector does not have the array allocated,
    1361:    so the intended usage is with VecPlaceArray().

    1363:    Level: developer

    1365: .seealso: BVCreateVec()
    1366: @*/
    1367: PetscErrorCode BVCreateVecEmpty(BV bv,Vec *v)
    1368: {
    1369:   PetscBool  standard,cuda,hip,mpi;
    1370:   PetscInt   N,nloc,bs;

    1372:   PetscFunctionBegin;
    1374:   BVCheckSizes(bv,1);
    1375:   PetscAssertPointer(v,2);

    1377:   PetscCall(PetscStrcmpAny(bv->vtype,&standard,VECSEQ,VECMPI,""));
    1378:   PetscCall(PetscStrcmpAny(bv->vtype,&cuda,VECSEQCUDA,VECMPICUDA,""));
    1379:   PetscCall(PetscStrcmpAny(bv->vtype,&hip,VECSEQHIP,VECMPIHIP,""));
    1380:   if (standard || cuda || hip) {
    1381:     PetscCall(PetscStrcmpAny(bv->vtype,&mpi,VECMPI,VECMPICUDA,VECMPIHIP,""));
    1382:     PetscCall(PetscLayoutGetLocalSize(bv->map,&nloc));
    1383:     PetscCall(PetscLayoutGetSize(bv->map,&N));
    1384:     PetscCall(PetscLayoutGetBlockSize(bv->map,&bs));
    1385:     if (cuda) {
    1386: #if defined(PETSC_HAVE_CUDA)
    1387:       if (mpi) PetscCall(VecCreateMPICUDAWithArray(PetscObjectComm((PetscObject)bv),bs,nloc,N,NULL,v));
    1388:       else PetscCall(VecCreateSeqCUDAWithArray(PetscObjectComm((PetscObject)bv),bs,N,NULL,v));
    1389: #endif
    1390:     } else if (hip) {
    1391: #if defined(PETSC_HAVE_HIP)
    1392:       if (mpi) PetscCall(VecCreateMPIHIPWithArray(PetscObjectComm((PetscObject)bv),bs,nloc,N,NULL,v));
    1393:       else PetscCall(VecCreateSeqHIPWithArray(PetscObjectComm((PetscObject)bv),bs,N,NULL,v));
    1394: #endif
    1395:     } else {
    1396:       if (mpi) PetscCall(VecCreateMPIWithArray(PetscObjectComm((PetscObject)bv),bs,nloc,N,NULL,v));
    1397:       else PetscCall(VecCreateSeqWithArray(PetscObjectComm((PetscObject)bv),bs,N,NULL,v));
    1398:     }
    1399:   } else PetscCall(BVCreateVec(bv,v)); /* standard duplicate, with internal array */
    1400:   PetscFunctionReturn(PETSC_SUCCESS);
    1401: }

    1403: /*@
    1404:    BVSetVecType - Set the vector type to be used when creating vectors via BVCreateVec().

    1406:    Collective

    1408:    Input Parameters:
    1409: +  bv - the basis vectors context
    1410: -  vtype - the vector type

    1412:    Level: advanced

    1414:    Note:
    1415:    This is not needed if the BV object is set up with BVSetSizesFromVec(), but may be
    1416:    required in the case of BVSetSizes() if one wants to work with non-standard vectors.

    1418: .seealso: BVGetVecType(), BVSetSizesFromVec(), BVSetSizes()
    1419: @*/
    1420: PetscErrorCode BVSetVecType(BV bv,VecType vtype)
    1421: {
    1422:   PetscBool   std;
    1423:   PetscMPIInt size;

    1425:   PetscFunctionBegin;
    1427:   PetscCall(PetscFree(bv->vtype));
    1428:   PetscCall(PetscStrcmp(vtype,VECSTANDARD,&std));
    1429:   if (std) {
    1430:     PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)bv),&size));
    1431:     PetscCall(PetscStrallocpy((size==1)?VECSEQ:VECMPI,(char**)&bv->vtype));
    1432:   } else PetscCall(PetscStrallocpy(vtype,(char**)&bv->vtype));
    1433:   PetscFunctionReturn(PETSC_SUCCESS);
    1434: }

    1436: /*@
    1437:    BVGetVecType - Get the vector type to be used when creating vectors via BVCreateVec().

    1439:    Not Collective

    1441:    Input Parameter:
    1442: .  bv - the basis vectors context

    1444:    Output Parameter:
    1445: .  vtype - the vector type

    1447:    Level: advanced

    1449: .seealso: BVSetVecType()
    1450: @*/
    1451: PetscErrorCode BVGetVecType(BV bv,VecType *vtype)
    1452: {
    1453:   PetscFunctionBegin;
    1455:   PetscAssertPointer(vtype,2);
    1456:   *vtype = bv->vtype;
    1457:   PetscFunctionReturn(PETSC_SUCCESS);
    1458: }

    1460: /*@
    1461:    BVCreateMat - Creates a new Mat object of dense type and copies the contents
    1462:    of the BV object.

    1464:    Collective

    1466:    Input Parameter:
    1467: .  bv - the basis vectors context

    1469:    Output Parameter:
    1470: .  A  - the new matrix

    1472:    Notes:
    1473:    The user is responsible of destroying the returned matrix.

    1475:    The matrix contains all columns of the BV, not just the active columns.

    1477:    Level: intermediate

    1479: .seealso: BVCreateFromMat(), BVCreateVec(), BVGetMat()
    1480: @*/
    1481: PetscErrorCode BVCreateMat(BV bv,Mat *A)
    1482: {
    1483:   PetscInt ksave,lsave;
    1484:   Mat      B;

    1486:   PetscFunctionBegin;
    1488:   BVCheckSizes(bv,1);
    1489:   PetscAssertPointer(A,2);

    1491:   PetscCall(MatCreateDenseFromVecType(PetscObjectComm((PetscObject)bv),bv->vtype,bv->n,PETSC_DECIDE,bv->N,bv->m,bv->ld,NULL,A));
    1492:   lsave = bv->l;
    1493:   ksave = bv->k;
    1494:   bv->l = 0;
    1495:   bv->k = bv->m;
    1496:   PetscCall(BVGetMat(bv,&B));
    1497:   PetscCall(MatCopy(B,*A,SAME_NONZERO_PATTERN));
    1498:   PetscCall(BVRestoreMat(bv,&B));
    1499:   bv->l = lsave;
    1500:   bv->k = ksave;
    1501:   PetscFunctionReturn(PETSC_SUCCESS);
    1502: }

    1504: PetscErrorCode BVGetMat_Default(BV bv,Mat *A)
    1505: {
    1506:   PetscScalar *vv,*aa;
    1507:   PetscBool   create=PETSC_FALSE;
    1508:   PetscInt    m,cols;

    1510:   PetscFunctionBegin;
    1511:   m = bv->k-bv->l;
    1512:   if (!bv->Aget) create=PETSC_TRUE;
    1513:   else {
    1514:     PetscCall(MatDenseGetArray(bv->Aget,&aa));
    1515:     PetscCheck(!aa,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"BVGetMat already called on this BV");
    1516:     PetscCall(MatGetSize(bv->Aget,NULL,&cols));
    1517:     if (cols!=m) {
    1518:       PetscCall(MatDestroy(&bv->Aget));
    1519:       create=PETSC_TRUE;
    1520:     }
    1521:   }
    1522:   PetscCall(BVGetArray(bv,&vv));
    1523:   if (create) {
    1524:     PetscCall(MatCreateDenseFromVecType(PetscObjectComm((PetscObject)bv),bv->vtype,bv->n,PETSC_DECIDE,bv->N,m,bv->ld,vv,&bv->Aget)); /* pass a pointer to avoid allocation of storage */
    1525:     PetscCall(MatDenseReplaceArray(bv->Aget,NULL));  /* replace with a null pointer, the value after BVRestoreMat */
    1526:   }
    1527:   PetscCall(MatDensePlaceArray(bv->Aget,vv+(bv->nc+bv->l)*bv->ld));  /* set the actual pointer */
    1528:   *A = bv->Aget;
    1529:   PetscFunctionReturn(PETSC_SUCCESS);
    1530: }

    1532: /*@
    1533:    BVGetMat - Returns a Mat object of dense type that shares the memory of
    1534:    the BV object.

    1536:    Collective

    1538:    Input Parameter:
    1539: .  bv - the basis vectors context

    1541:    Output Parameter:
    1542: .  A  - the matrix

    1544:    Notes:
    1545:    The returned matrix contains only the active columns. If the content of
    1546:    the Mat is modified, these changes are also done in the BV object. The
    1547:    user must call BVRestoreMat() when no longer needed.

    1549:    This operation implies a call to BVGetArray(), which may result in data
    1550:    copies.

    1552:    Level: advanced

    1554: .seealso: BVRestoreMat(), BVCreateMat(), BVGetArray()
    1555: @*/
    1556: PetscErrorCode BVGetMat(BV bv,Mat *A)
    1557: {
    1558:   char name[64];

    1560:   PetscFunctionBegin;
    1562:   BVCheckSizes(bv,1);
    1563:   PetscAssertPointer(A,2);
    1564:   PetscUseTypeMethod(bv,getmat,A);
    1565:   if (((PetscObject)bv)->name) {   /* set A's name based on BV name */
    1566:     PetscCall(PetscStrncpy(name,"Mat_",sizeof(name)));
    1567:     PetscCall(PetscStrlcat(name,((PetscObject)bv)->name,sizeof(name)));
    1568:     PetscCall(PetscObjectSetName((PetscObject)*A,name));
    1569:   }
    1570:   PetscFunctionReturn(PETSC_SUCCESS);
    1571: }

    1573: PetscErrorCode BVRestoreMat_Default(BV bv,Mat *A)
    1574: {
    1575:   PetscScalar *vv,*aa;

    1577:   PetscFunctionBegin;
    1578:   PetscCall(MatDenseGetArray(bv->Aget,&aa));
    1579:   vv = aa-(bv->nc+bv->l)*bv->ld;
    1580:   PetscCall(MatDenseResetArray(bv->Aget));
    1581:   PetscCall(BVRestoreArray(bv,&vv));
    1582:   *A = NULL;
    1583:   PetscFunctionReturn(PETSC_SUCCESS);
    1584: }

    1586: /*@
    1587:    BVRestoreMat - Restores the Mat obtained with BVGetMat().

    1589:    Logically Collective

    1591:    Input Parameters:
    1592: +  bv - the basis vectors context
    1593: -  A  - the fetched matrix

    1595:    Note:
    1596:    A call to this function must match a previous call of BVGetMat().
    1597:    The effect is that the contents of the Mat are copied back to the
    1598:    BV internal data structures.

    1600:    Level: advanced

    1602: .seealso: BVGetMat(), BVRestoreArray()
    1603: @*/
    1604: PetscErrorCode BVRestoreMat(BV bv,Mat *A)
    1605: {
    1606:   PetscFunctionBegin;
    1608:   BVCheckSizes(bv,1);
    1609:   PetscAssertPointer(A,2);
    1610:   PetscCheck(bv->Aget,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"BVRestoreMat must match a previous call to BVGetMat");
    1611:   PetscCheck(bv->Aget==*A,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Mat argument is not the same as the one obtained with BVGetMat");
    1612:   PetscUseTypeMethod(bv,restoremat,A);
    1613:   PetscFunctionReturn(PETSC_SUCCESS);
    1614: }

    1616: /*
    1617:    Copy all user-provided attributes of V to another BV object W
    1618:  */
    1619: static inline PetscErrorCode BVDuplicate_Private(BV V,BV W)
    1620: {
    1621:   PetscFunctionBegin;
    1622:   PetscCall(PetscLayoutReference(V->map,&W->map));
    1623:   PetscCall(BVSetVecType(W,V->vtype));
    1624:   W->ld           = V->ld;
    1625:   PetscCall(BVSetType(W,((PetscObject)V)->type_name));
    1626:   W->orthog_type  = V->orthog_type;
    1627:   W->orthog_ref   = V->orthog_ref;
    1628:   W->orthog_eta   = V->orthog_eta;
    1629:   W->orthog_block = V->orthog_block;
    1630:   if (V->matrix) PetscCall(PetscObjectReference((PetscObject)V->matrix));
    1631:   W->matrix       = V->matrix;
    1632:   W->indef        = V->indef;
    1633:   W->vmm          = V->vmm;
    1634:   W->rrandom      = V->rrandom;
    1635:   W->deftol       = V->deftol;
    1636:   if (V->rand) PetscCall(PetscObjectReference((PetscObject)V->rand));
    1637:   W->rand         = V->rand;
    1638:   W->sfocalled    = V->sfocalled;
    1639:   PetscTryTypeMethod(V,duplicate,W);
    1640:   PetscCall(PetscObjectStateIncrease((PetscObject)W));
    1641:   PetscFunctionReturn(PETSC_SUCCESS);
    1642: }

    1644: /*@
    1645:    BVDuplicate - Creates a new basis vector object of the same type and
    1646:    dimensions as an existing one.

    1648:    Collective

    1650:    Input Parameter:
    1651: .  V - basis vectors context

    1653:    Output Parameter:
    1654: .  W - location to put the new BV

    1656:    Notes:
    1657:    The new BV has the same type and dimensions as V. Also, the inner
    1658:    product matrix and orthogonalization options are copied.

    1660:    BVDuplicate() DOES NOT COPY the entries, but rather allocates storage
    1661:    for the new basis vectors. Use BVCopy() to copy the contents.

    1663:    Level: intermediate

    1665: .seealso: BVDuplicateResize(), BVCreate(), BVSetSizesFromVec(), BVCopy()
    1666: @*/
    1667: PetscErrorCode BVDuplicate(BV V,BV *W)
    1668: {
    1669:   PetscFunctionBegin;
    1672:   BVCheckSizes(V,1);
    1673:   PetscAssertPointer(W,2);
    1674:   PetscCall(BVCreate(PetscObjectComm((PetscObject)V),W));
    1675:   (*W)->N = V->N;
    1676:   (*W)->n = V->n;
    1677:   (*W)->m = V->m;
    1678:   (*W)->k = V->m;
    1679:   PetscCall(BVDuplicate_Private(V,*W));
    1680:   PetscFunctionReturn(PETSC_SUCCESS);
    1681: }

    1683: /*@
    1684:    BVDuplicateResize - Creates a new basis vector object of the same type and
    1685:    dimensions as an existing one, but with possibly different number of columns.

    1687:    Collective

    1689:    Input Parameters:
    1690: +  V - basis vectors context
    1691: -  m - the new number of columns

    1693:    Output Parameter:
    1694: .  W - location to put the new BV

    1696:    Note:
    1697:    This is equivalent of a call to BVDuplicate() followed by BVResize(). The
    1698:    contents of V are not copied to W.

    1700:    Level: intermediate

    1702: .seealso: BVDuplicate(), BVResize()
    1703: @*/
    1704: PetscErrorCode BVDuplicateResize(BV V,PetscInt m,BV *W)
    1705: {
    1706:   PetscFunctionBegin;
    1709:   BVCheckSizes(V,1);
    1711:   PetscAssertPointer(W,3);
    1712:   PetscCall(BVCreate(PetscObjectComm((PetscObject)V),W));
    1713:   (*W)->N = V->N;
    1714:   (*W)->n = V->n;
    1715:   (*W)->m = m;
    1716:   (*W)->k = m;
    1717:   PetscCall(BVDuplicate_Private(V,*W));
    1718:   PetscFunctionReturn(PETSC_SUCCESS);
    1719: }

    1721: /*@
    1722:    BVGetCachedBV - Returns a BV object stored internally that holds the
    1723:    result of B*X after a call to BVApplyMatrixBV().

    1725:    Collective

    1727:    Input Parameter:
    1728: .  bv    - the basis vectors context

    1730:    Output Parameter:
    1731: .  cached - the cached BV

    1733:    Note:
    1734:    The cached BV is created if not available previously.

    1736:    Level: developer

    1738: .seealso: BVApplyMatrixBV()
    1739: @*/
    1740: PetscErrorCode BVGetCachedBV(BV bv,BV *cached)
    1741: {
    1742:   PetscFunctionBegin;
    1744:   PetscAssertPointer(cached,2);
    1745:   BVCheckSizes(bv,1);
    1746:   if (!bv->cached) {
    1747:     PetscCall(BVCreate(PetscObjectComm((PetscObject)bv),&bv->cached));
    1748:     bv->cached->N = bv->N;
    1749:     bv->cached->n = bv->n;
    1750:     bv->cached->m = bv->m;
    1751:     bv->cached->k = bv->m;
    1752:     PetscCall(BVDuplicate_Private(bv,bv->cached));
    1753:   }
    1754:   *cached = bv->cached;
    1755:   PetscFunctionReturn(PETSC_SUCCESS);
    1756: }

    1758: /*@
    1759:    BVCopy - Copies a basis vector object into another one, W <- V.

    1761:    Logically Collective

    1763:    Input Parameter:
    1764: .  V - basis vectors context

    1766:    Output Parameter:
    1767: .  W - the copy

    1769:    Note:
    1770:    Both V and W must be distributed in the same manner; local copies are
    1771:    done. Only active columns (excluding the leading ones) are copied.
    1772:    In the destination W, columns are overwritten starting from the leading ones.
    1773:    Constraints are not copied.

    1775:    Level: beginner

    1777: .seealso: BVCopyVec(), BVCopyColumn(), BVDuplicate(), BVSetActiveColumns()
    1778: @*/
    1779: PetscErrorCode BVCopy(BV V,BV W)
    1780: {
    1781:   PetscScalar       *womega;
    1782:   const PetscScalar *vomega;

    1784:   PetscFunctionBegin;
    1787:   BVCheckSizes(V,1);
    1788:   BVCheckOp(V,1,copy);
    1791:   BVCheckSizes(W,2);
    1792:   PetscCheckSameTypeAndComm(V,1,W,2);
    1793:   PetscCheck(V->n==W->n,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_INCOMP,"Mismatching local dimension V %" PetscInt_FMT ", W %" PetscInt_FMT,V->n,W->n);
    1794:   PetscCheck(V->k-V->l<=W->m-W->l,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_SIZ,"W has %" PetscInt_FMT " non-leading columns, not enough to store %" PetscInt_FMT " columns",W->m-W->l,V->k-V->l);
    1795:   if (V==W || !V->n) PetscFunctionReturn(PETSC_SUCCESS);

    1797:   PetscCall(PetscLogEventBegin(BV_Copy,V,W,0,0));
    1798:   if (V->indef && V->matrix && V->indef==W->indef && V->matrix==W->matrix) {
    1799:     /* copy signature */
    1800:     PetscCall(BV_AllocateSignature(W));
    1801:     PetscCall(VecGetArrayRead(V->omega,&vomega));
    1802:     PetscCall(VecGetArray(W->omega,&womega));
    1803:     PetscCall(PetscArraycpy(womega+W->nc+W->l,vomega+V->nc+V->l,V->k-V->l));
    1804:     PetscCall(VecRestoreArray(W->omega,&womega));
    1805:     PetscCall(VecRestoreArrayRead(V->omega,&vomega));
    1806:   }
    1807:   PetscUseTypeMethod(V,copy,W);
    1808:   PetscCall(PetscLogEventEnd(BV_Copy,V,W,0,0));
    1809:   PetscCall(PetscObjectStateIncrease((PetscObject)W));
    1810:   PetscFunctionReturn(PETSC_SUCCESS);
    1811: }

    1813: /*@
    1814:    BVCopyVec - Copies one of the columns of a basis vectors object into a Vec.

    1816:    Logically Collective

    1818:    Input Parameters:
    1819: +  V - basis vectors context
    1820: -  j - the column number to be copied

    1822:    Output Parameter:
    1823: .  w - the copied column

    1825:    Note:
    1826:    Both V and w must be distributed in the same manner; local copies are done.

    1828:    Level: beginner

    1830: .seealso: BVCopy(), BVCopyColumn(), BVInsertVec()
    1831: @*/
    1832: PetscErrorCode BVCopyVec(BV V,PetscInt j,Vec w)
    1833: {
    1834:   PetscInt       n,N;
    1835:   Vec            z;

    1837:   PetscFunctionBegin;
    1840:   BVCheckSizes(V,1);
    1843:   PetscCheckSameComm(V,1,w,3);

    1845:   PetscCall(VecGetSize(w,&N));
    1846:   PetscCall(VecGetLocalSize(w,&n));
    1847:   PetscCheck(N==V->N && n==V->n,PetscObjectComm((PetscObject)V),PETSC_ERR_ARG_INCOMP,"Vec sizes (global %" PetscInt_FMT ", local %" PetscInt_FMT ") do not match BV sizes (global %" PetscInt_FMT ", local %" PetscInt_FMT ")",N,n,V->N,V->n);

    1849:   PetscCall(PetscLogEventBegin(BV_Copy,V,w,0,0));
    1850:   PetscCall(BVGetColumn(V,j,&z));
    1851:   PetscCall(VecCopy(z,w));
    1852:   PetscCall(BVRestoreColumn(V,j,&z));
    1853:   PetscCall(PetscLogEventEnd(BV_Copy,V,w,0,0));
    1854:   PetscFunctionReturn(PETSC_SUCCESS);
    1855: }

    1857: /*@
    1858:    BVCopyColumn - Copies the values from one of the columns to another one.

    1860:    Logically Collective

    1862:    Input Parameters:
    1863: +  V - basis vectors context
    1864: .  j - the number of the source column
    1865: -  i - the number of the destination column

    1867:    Level: beginner

    1869: .seealso: BVCopy(), BVCopyVec()
    1870: @*/
    1871: PetscErrorCode BVCopyColumn(BV V,PetscInt j,PetscInt i)
    1872: {
    1873:   PetscScalar *omega;

    1875:   PetscFunctionBegin;
    1878:   BVCheckSizes(V,1);
    1881:   if (j==i) PetscFunctionReturn(PETSC_SUCCESS);

    1883:   PetscCall(PetscLogEventBegin(BV_Copy,V,0,0,0));
    1884:   if (V->omega) {
    1885:     PetscCall(VecGetArray(V->omega,&omega));
    1886:     omega[i] = omega[j];
    1887:     PetscCall(VecRestoreArray(V->omega,&omega));
    1888:   }
    1889:   PetscUseTypeMethod(V,copycolumn,j,i);
    1890:   PetscCall(PetscLogEventEnd(BV_Copy,V,0,0,0));
    1891:   PetscCall(PetscObjectStateIncrease((PetscObject)V));
    1892:   PetscFunctionReturn(PETSC_SUCCESS);
    1893: }

    1895: static PetscErrorCode BVGetSplit_Private(BV bv,PetscBool left,BV *split)
    1896: {
    1897:   PetscInt  ncols;

    1899:   PetscFunctionBegin;
    1900:   ncols = left? bv->nc+bv->l: bv->m-bv->l;
    1901:   if (*split && (ncols!=(*split)->m || bv->N!=(*split)->N)) PetscCall(BVDestroy(split));
    1902:   if (!*split) {
    1903:     PetscCall(BVCreate(PetscObjectComm((PetscObject)bv),split));
    1904:     (*split)->issplit = left? 1: 2;
    1905:     (*split)->splitparent = bv;
    1906:     (*split)->N = bv->N;
    1907:     (*split)->n = bv->n;
    1908:     (*split)->m = bv->m;
    1909:     (*split)->k = bv->m;
    1910:     PetscCall(BVDuplicate_Private(bv,*split));
    1911:   }
    1912:   (*split)->l  = 0;
    1913:   (*split)->k  = left? bv->l: bv->k-bv->l;
    1914:   (*split)->nc = left? bv->nc: 0;
    1915:   (*split)->m  = ncols-(*split)->nc;
    1916:   if ((*split)->nc) {
    1917:     (*split)->ci[0] = -(*split)->nc-1;
    1918:     (*split)->ci[1] = -(*split)->nc-1;
    1919:   }
    1920:   if (left) PetscCall(PetscObjectStateGet((PetscObject)*split,&bv->lstate));
    1921:   else PetscCall(PetscObjectStateGet((PetscObject)*split,&bv->rstate));
    1922:   PetscFunctionReturn(PETSC_SUCCESS);
    1923: }

    1925: /*@
    1926:    BVGetSplit - Splits the BV object into two BV objects that share the
    1927:    internal data, one of them containing the leading columns and the other
    1928:    one containing the remaining columns.

    1930:    Collective

    1932:    Input Parameter:
    1933: .  bv - the basis vectors context

    1935:    Output Parameters:
    1936: +  L - left BV containing leading columns (can be NULL)
    1937: -  R - right BV containing remaining columns (can be NULL)

    1939:    Notes:
    1940:    The columns are split in two sets. The leading columns (including the
    1941:    constraints) are assigned to the left BV and the remaining columns
    1942:    are assigned to the right BV. The number of leading columns, as
    1943:    specified with BVSetActiveColumns(), must be between 1 and m-1 (to
    1944:    guarantee that both L and R have at least one column).

    1946:    The returned BV's must be seen as references (not copies) of the input
    1947:    BV, that is, modifying them will change the entries of bv as well.
    1948:    The returned BV's must not be destroyed. BVRestoreSplit() must be called
    1949:    when they are no longer needed.

    1951:    Pass NULL for any of the output BV's that is not needed.

    1953:    Level: advanced

    1955: .seealso: BVRestoreSplit(), BVSetActiveColumns(), BVSetNumConstraints(), BVGetSplitRows()
    1956: @*/
    1957: PetscErrorCode BVGetSplit(BV bv,BV *L,BV *R)
    1958: {
    1959:   PetscFunctionBegin;
    1962:   BVCheckSizes(bv,1);
    1963:   PetscCheck(bv->l,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Must indicate the number of leading columns with BVSetActiveColumns()");
    1964:   PetscCheck(bv->lsplit>=0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Cannot call BVGetSplit() after BVGetSplitRows()");
    1965:   PetscCheck(!bv->lsplit,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Cannot get the split BV's twice before restoring them with BVRestoreSplit()");
    1966:   bv->lsplit = bv->nc+bv->l;
    1967:   PetscCall(BVGetSplit_Private(bv,PETSC_TRUE,&bv->L));
    1968:   PetscCall(BVGetSplit_Private(bv,PETSC_FALSE,&bv->R));
    1969:   if (L) *L = bv->L;
    1970:   if (R) *R = bv->R;
    1971:   PetscFunctionReturn(PETSC_SUCCESS);
    1972: }

    1974: /*@
    1975:    BVRestoreSplit - Restore the BV objects obtained with BVGetSplit().

    1977:    Logically Collective

    1979:    Input Parameters:
    1980: +  bv - the basis vectors context
    1981: .  L  - left BV obtained with BVGetSplit()
    1982: -  R  - right BV obtained with BVGetSplit()

    1984:    Note:
    1985:    The arguments must match the corresponding call to BVGetSplit().

    1987:    Level: advanced

    1989: .seealso: BVGetSplit()
    1990: @*/
    1991: PetscErrorCode BVRestoreSplit(BV bv,BV *L,BV *R)
    1992: {
    1993:   PetscFunctionBegin;
    1996:   BVCheckSizes(bv,1);
    1997:   PetscCheck(bv->lsplit>0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Must call BVGetSplit first");
    1998:   PetscCheck(!L || *L==bv->L,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Argument 2 is not the same BV that was obtained with BVGetSplit");
    1999:   PetscCheck(!R || *R==bv->R,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Argument 3 is not the same BV that was obtained with BVGetSplit");
    2000:   PetscCheck(!L || ((*L)->ci[0]<=(*L)->nc-1 && (*L)->ci[1]<=(*L)->nc-1),PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Argument 2 has unrestored columns, use BVRestoreColumn()");
    2001:   PetscCheck(!R || ((*R)->ci[0]<=(*R)->nc-1 && (*R)->ci[1]<=(*R)->nc-1),PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Argument 3 has unrestored columns, use BVRestoreColumn()");

    2003:   PetscTryTypeMethod(bv,restoresplit,L,R);
    2004:   bv->lsplit = 0;
    2005:   if (L) *L = NULL;
    2006:   if (R) *R = NULL;
    2007:   PetscFunctionReturn(PETSC_SUCCESS);
    2008: }

    2010: /*
    2011:    Copy all user-provided attributes of V to another BV object W with different layout
    2012:  */
    2013: static inline PetscErrorCode BVDuplicateNewLayout_Private(BV V,BV W)
    2014: {
    2015:   PetscFunctionBegin;
    2016:   PetscCall(PetscLayoutCreateFromSizes(PetscObjectComm((PetscObject)V),W->n,W->N,1,&W->map));
    2017:   PetscCall(BVSetVecType(W,V->vtype));
    2018:   W->ld           = V->ld;
    2019:   PetscCall(BVSetType(W,((PetscObject)V)->type_name));
    2020:   W->orthog_type  = V->orthog_type;
    2021:   W->orthog_ref   = V->orthog_ref;
    2022:   W->orthog_eta   = V->orthog_eta;
    2023:   W->orthog_block = V->orthog_block;
    2024:   W->vmm          = V->vmm;
    2025:   W->rrandom      = V->rrandom;
    2026:   W->deftol       = V->deftol;
    2027:   if (V->rand) PetscCall(PetscObjectReference((PetscObject)V->rand));
    2028:   W->rand         = V->rand;
    2029:   W->sfocalled    = V->sfocalled;
    2030:   PetscTryTypeMethod(V,duplicate,W);
    2031:   PetscCall(PetscObjectStateIncrease((PetscObject)W));
    2032:   PetscFunctionReturn(PETSC_SUCCESS);
    2033: }

    2035: static PetscErrorCode BVGetSplitRows_Private(BV bv,PetscBool top,IS is,BV *split)
    2036: {
    2037:   PetscInt  rstart,rend,lstart;
    2038:   PetscInt  N,n;
    2039:   PetscBool contig;

    2041:   PetscFunctionBegin;
    2042:   PetscCall(PetscLayoutGetRange(bv->map,&rstart,&rend));
    2043:   PetscCall(ISContiguousLocal(is,rstart,rend,&lstart,&contig));
    2044:   PetscCheck(contig,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"%s index set is not contiguous",(top==PETSC_TRUE)?"Upper":"Lower");
    2045:   if (top) PetscCheck(lstart==0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONG,"Upper index set should start at first local row");
    2046:   else bv->lsplit = -lstart;
    2047:   PetscCall(ISGetSize(is,&N));
    2048:   PetscCall(ISGetLocalSize(is,&n));
    2049:   if (*split && (bv->m!=(*split)->m || N!=(*split)->N)) PetscCall(BVDestroy(split));
    2050:   if (!*split) {
    2051:     PetscCall(BVCreate(PetscObjectComm((PetscObject)bv),split));
    2052:     (*split)->issplit = top? -1: -2;
    2053:     (*split)->splitparent = bv;
    2054:     (*split)->N = N;
    2055:     (*split)->n = n;
    2056:     (*split)->m = bv->m;
    2057:     PetscCall(BVDuplicateNewLayout_Private(bv,*split));
    2058:   }
    2059:   (*split)->k  = bv->k;
    2060:   (*split)->l  = bv->l;
    2061:   (*split)->nc = bv->nc;
    2062:   if ((*split)->nc) {
    2063:     (*split)->ci[0] = -(*split)->nc-1;
    2064:     (*split)->ci[1] = -(*split)->nc-1;
    2065:   }
    2066:   if (top) PetscCall(PetscObjectStateGet((PetscObject)*split,&bv->rstate));
    2067:   else PetscCall(PetscObjectStateGet((PetscObject)*split,&bv->lstate));
    2068:   PetscFunctionReturn(PETSC_SUCCESS);
    2069: }

    2071: /*@
    2072:    BVGetSplitRows - Splits the BV object into two BV objects that share the
    2073:    internal data, using a disjoint horizontal splitting.

    2075:    Collective

    2077:    Input Parameters:
    2078: +  bv   - the basis vectors context
    2079: .  isup - the index set that defines the upper part of the horizontal splitting
    2080: -  islo - the index set that defines the lower part of the horizontal splitting

    2082:    Output Parameters:
    2083: +  U - the resulting BV containing the upper rows
    2084: -  L - the resulting BV containing the lower rows

    2086:    Notes:
    2087:    The index sets must be such that every MPI process can extract the selected
    2088:    rows from its local part of the input BV, and this part must be contiguous.
    2089:    With one process, isup will list contiguous indices starting from 0, and islo
    2090:    will contain the remaining indices, hence we refer to upper and lower part.
    2091:    However, with several processes the indices will be interleaved because
    2092:    isup will refer to the upper part of the local array.

    2094:    The intended use of this function is with matrices of MATNEST type, where
    2095:    MatNestGetISs() will return the appropriate index sets.

    2097:    The returned BV's must be seen as references (not copies) of the input
    2098:    BV, that is, modifying them will change the entries of bv as well.
    2099:    The returned BV's must not be destroyed. BVRestoreSplitRows() must be called
    2100:    when they are no longer needed.

    2102:    Pass NULL for any of the output BV's that is not needed.

    2104:    Level: advanced

    2106: .seealso: BVRestoreSplitRows(), BVGetSplit()
    2107: @*/
    2108: PetscErrorCode BVGetSplitRows(BV bv,IS isup,IS islo,BV *U,BV *L)
    2109: {
    2110:   PetscFunctionBegin;
    2113:   BVCheckSizes(bv,1);
    2116:   PetscCheck(bv->lsplit<=0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Cannot call BVGetSplitRows() after BVGetSplit()");
    2117:   PetscCheck(!bv->lsplit,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Cannot get the split BV's twice before restoring them with BVRestoreSplitRows()");
    2118:   if (U) {
    2119:     PetscCall(BVGetSplitRows_Private(bv,PETSC_TRUE,isup,&bv->R));
    2120:     *U = bv->R;
    2121:   }
    2122:   if (L) {
    2123:     PetscCall(BVGetSplitRows_Private(bv,PETSC_FALSE,islo,&bv->L));
    2124:     *L = bv->L;
    2125:   }
    2126:   PetscFunctionReturn(PETSC_SUCCESS);
    2127: }

    2129: /*@
    2130:    BVRestoreSplitRows - Restore the BV objects obtained with BVGetSplitRows().

    2132:    Logically Collective

    2134:    Input Parameters:
    2135: +  bv - the basis vectors context
    2136: .  isup - the index set that defines the upper part of the horizontal splitting
    2137: .  islo - the index set that defines the lower part of the horizontal splitting
    2138: .  U - the BV containing the upper rows
    2139: -  L - the BV containing the lower rows

    2141:    Note:
    2142:    The arguments must match the corresponding call to BVGetSplitRows().

    2144:    Level: advanced

    2146: .seealso: BVGetSplitRows()
    2147: @*/
    2148: PetscErrorCode BVRestoreSplitRows(BV bv,IS isup,IS islo,BV *U,BV *L)
    2149: {
    2150:   PetscFunctionBegin;
    2153:   BVCheckSizes(bv,1);
    2154:   PetscCheck(bv->lsplit<0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"Must call BVGetSplitRows first");
    2155:   PetscCheck(!U || ((*U)->ci[0]<=(*U)->nc-1 && (*U)->ci[1]<=(*U)->nc-1),PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"The upper BV has unrestored columns, use BVRestoreColumn()");
    2156:   PetscCheck(!L || ((*L)->ci[0]<=(*L)->nc-1 && (*L)->ci[1]<=(*L)->nc-1),PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_WRONGSTATE,"The lower BV has unrestored columns, use BVRestoreColumn()");
    2157:   PetscTryTypeMethod(bv,restoresplitrows,isup,islo,U,L);
    2158:   bv->lsplit = 0;
    2159:   PetscFunctionReturn(PETSC_SUCCESS);
    2160: }

    2162: /*@
    2163:    BVSetDefiniteTolerance - Set the tolerance to be used when checking a
    2164:    definite inner product.

    2166:    Logically Collective

    2168:    Input Parameters:
    2169: +  bv     - basis vectors
    2170: -  deftol - the tolerance

    2172:    Options Database Key:
    2173: .  -bv_definite_tol <deftol> - the tolerance

    2175:    Notes:
    2176:    When using a non-standard inner product, see BVSetMatrix(), the solver needs
    2177:    to compute sqrt(z'*B*z) for various vectors z. If the inner product has not
    2178:    been declared indefinite, the value z'*B*z must be positive, but due to
    2179:    rounding error a tiny value may become negative. A tolerance is used to
    2180:    detect this situation. Likewise, in complex arithmetic z'*B*z should be
    2181:    real, and we use the same tolerance to check whether a nonzero imaginary part
    2182:    can be considered negligible.

    2184:    This function sets this tolerance, which defaults to 10*eps, where eps is
    2185:    the machine epsilon. The default value should be good for most applications.

    2187:    Level: advanced

    2189: .seealso: BVSetMatrix()
    2190: @*/
    2191: PetscErrorCode BVSetDefiniteTolerance(BV bv,PetscReal deftol)
    2192: {
    2193:   PetscFunctionBegin;
    2196:   if (deftol == (PetscReal)PETSC_DEFAULT || deftol == (PetscReal)PETSC_DECIDE) bv->deftol = 10*PETSC_MACHINE_EPSILON;
    2197:   else {
    2198:     PetscCheck(deftol>0.0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of deftol. Must be > 0");
    2199:     bv->deftol = deftol;
    2200:   }
    2201:   PetscFunctionReturn(PETSC_SUCCESS);
    2202: }

    2204: /*@
    2205:    BVGetDefiniteTolerance - Returns the tolerance for checking a definite
    2206:    inner product.

    2208:    Not Collective

    2210:    Input Parameter:
    2211: .  bv - the basis vectors

    2213:    Output Parameter:
    2214: .  deftol - the tolerance

    2216:    Level: advanced

    2218: .seealso: BVSetDefiniteTolerance()
    2219: @*/
    2220: PetscErrorCode BVGetDefiniteTolerance(BV bv,PetscReal *deftol)
    2221: {
    2222:   PetscFunctionBegin;
    2224:   PetscAssertPointer(deftol,2);
    2225:   *deftol = bv->deftol;
    2226:   PetscFunctionReturn(PETSC_SUCCESS);
    2227: }

    2229: /*@
    2230:    BVSetLeadingDimension - Set the leading dimension to be used for storing the BV data.

    2232:    Not Collective

    2234:    Input Parameters:
    2235: +  bv - basis vectors
    2236: -  ld - the leading dimension

    2238:    Notes:
    2239:    This parameter is relevant for BVMAT, though it might be employed in other types
    2240:    as well.

    2242:    When the internal data of the BV is stored as a dense matrix, the leading dimension
    2243:    has the same meaning as in MatDenseSetLDA(), i.e., the distance in number of
    2244:    elements from one entry of the matrix to the one in the next column at the same
    2245:    row. The leading dimension refers to the local array, and hence can be different
    2246:    in different processes.

    2248:    The user does not need to change this parameter. The default value is equal to the
    2249:    number of local rows, but this value may be increased a little to guarantee alignment
    2250:    (especially in the case of GPU storage).

    2252:    Level: advanced

    2254: .seealso: BVGetLeadingDimension()
    2255: @*/
    2256: PetscErrorCode BVSetLeadingDimension(BV bv,PetscInt ld)
    2257: {
    2258:   PetscFunctionBegin;
    2261:   PetscCheck((bv->n<0 && bv->N<0) || !bv->ops->create,PetscObjectComm((PetscObject)bv),PETSC_ERR_ORDER,"Must call BVSetLeadingDimension() before setting the BV type and sizes");
    2262:   if (ld == PETSC_DEFAULT || ld == PETSC_DECIDE) bv->ld = 0;
    2263:   else {
    2264:     PetscCheck(ld>0,PetscObjectComm((PetscObject)bv),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of ld. Must be > 0");
    2265:     bv->ld = ld;
    2266:   }
    2267:   PetscFunctionReturn(PETSC_SUCCESS);
    2268: }

    2270: /*@
    2271:    BVGetLeadingDimension - Returns the leading dimension of the BV.

    2273:    Not Collective

    2275:    Input Parameter:
    2276: .  bv - the basis vectors

    2278:    Output Parameter:
    2279: .  ld - the leading dimension

    2281:    Level: advanced

    2283:    Notes:
    2284:    The returned value may be different in different processes.

    2286:    The leading dimension must be used when accessing the internal array via
    2287:    BVGetArray() or BVGetArrayRead().

    2289: .seealso: BVSetLeadingDimension(), BVGetArray(), BVGetArrayRead()
    2290: @*/
    2291: PetscErrorCode BVGetLeadingDimension(BV bv,PetscInt *ld)
    2292: {
    2293:   PetscFunctionBegin;
    2295:   PetscAssertPointer(ld,2);
    2296:   *ld = bv->ld;
    2297:   PetscFunctionReturn(PETSC_SUCCESS);
    2298: }