Date: 2023-11-27T17:19:35+00:00

Actual source code: dsbasic.c
slepc-3.20.1 2023-11-27
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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 DS routines
     12: */

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

     16: PetscFunctionList DSList = NULL;
     17: PetscBool         DSRegisterAllCalled = PETSC_FALSE;
     18: PetscClassId      DS_CLASSID = 0;
     19: PetscLogEvent     DS_Solve = 0,DS_Vectors = 0,DS_Synchronize = 0,DS_Other = 0;
     20: static PetscBool  DSPackageInitialized = PETSC_FALSE;

     22: const char *DSStateTypes[] = {"RAW","INTERMEDIATE","CONDENSED","TRUNCATED","DSStateType","DS_STATE_",NULL};
     23: const char *DSParallelTypes[] = {"REDUNDANT","SYNCHRONIZED","DISTRIBUTED","DSParallelType","DS_PARALLEL_",NULL};
     24: const char *DSMatName[DS_NUM_MAT] = {"A","B","C","T","D","Q","Z","X","Y","U","V","W","E0","E1","E2","E3","E4","E5","E6","E7","E8","E9"};
     25: DSMatType  DSMatExtra[DS_NUM_EXTRA] = {DS_MAT_E0,DS_MAT_E1,DS_MAT_E2,DS_MAT_E3,DS_MAT_E4,DS_MAT_E5,DS_MAT_E6,DS_MAT_E7,DS_MAT_E8,DS_MAT_E9};

     27: /*@C
     28:    DSFinalizePackage - This function destroys everything in the SLEPc interface
     29:    to the DS package. It is called from SlepcFinalize().

     31:    Level: developer

     33: .seealso: SlepcFinalize()
     34: @*/
     35: PetscErrorCode DSFinalizePackage(void)
     36: {
     37:   PetscFunctionBegin;
     38:   PetscCall(PetscFunctionListDestroy(&DSList));
     39:   DSPackageInitialized = PETSC_FALSE;
     40:   DSRegisterAllCalled  = PETSC_FALSE;
     41:   PetscFunctionReturn(PETSC_SUCCESS);
     42: }

     44: /*@C
     45:   DSInitializePackage - This function initializes everything in the DS package.
     46:   It is called from PetscDLLibraryRegister() when using dynamic libraries, and
     47:   on the first call to DSCreate() when using static libraries.

     49:   Level: developer

     51: .seealso: SlepcInitialize()
     52: @*/
     53: PetscErrorCode DSInitializePackage(void)
     54: {
     55:   char           logList[256];
     56:   PetscBool      opt,pkg;
     57:   PetscClassId   classids[1];

     59:   PetscFunctionBegin;
     60:   if (DSPackageInitialized) PetscFunctionReturn(PETSC_SUCCESS);
     61:   DSPackageInitialized = PETSC_TRUE;
     62:   /* Register Classes */
     63:   PetscCall(PetscClassIdRegister("Direct Solver",&DS_CLASSID));
     64:   /* Register Constructors */
     65:   PetscCall(DSRegisterAll());
     66:   /* Register Events */
     67:   PetscCall(PetscLogEventRegister("DSSolve",DS_CLASSID,&DS_Solve));
     68:   PetscCall(PetscLogEventRegister("DSVectors",DS_CLASSID,&DS_Vectors));
     69:   PetscCall(PetscLogEventRegister("DSSynchronize",DS_CLASSID,&DS_Synchronize));
     70:   PetscCall(PetscLogEventRegister("DSOther",DS_CLASSID,&DS_Other));
     71:   /* Process Info */
     72:   classids[0] = DS_CLASSID;
     73:   PetscCall(PetscInfoProcessClass("ds",1,&classids[0]));
     74:   /* Process summary exclusions */
     75:   PetscCall(PetscOptionsGetString(NULL,NULL,"-log_exclude",logList,sizeof(logList),&opt));
     76:   if (opt) {
     77:     PetscCall(PetscStrInList("ds",logList,',',&pkg));
     78:     if (pkg) PetscCall(PetscLogEventDeactivateClass(DS_CLASSID));
     79:   }
     80:   /* Register package finalizer */
     81:   PetscCall(PetscRegisterFinalize(DSFinalizePackage));
     82:   PetscFunctionReturn(PETSC_SUCCESS);
     83: }

     85: /*@
     86:    DSCreate - Creates a DS context.

     88:    Collective

     90:    Input Parameter:
     91: .  comm - MPI communicator

     93:    Output Parameter:
     94: .  newds - location to put the DS context

     96:    Level: beginner

     98:    Note:
     99:    DS objects are not intended for normal users but only for
    100:    advanced user that for instance implement their own solvers.

    102: .seealso: DSDestroy(), DS
    103: @*/
    104: PetscErrorCode DSCreate(MPI_Comm comm,DS *newds)
    105: {
    106:   DS             ds;
    107:   PetscInt       i;

    109:   PetscFunctionBegin;
    110:   PetscAssertPointer(newds,2);
    111:   *newds = NULL;
    112:   PetscCall(DSInitializePackage());
    113:   PetscCall(SlepcHeaderCreate(ds,DS_CLASSID,"DS","Direct Solver (or Dense System)","DS",comm,DSDestroy,DSView));

    115:   ds->state         = DS_STATE_RAW;
    116:   ds->method        = 0;
    117:   ds->compact       = PETSC_FALSE;
    118:   ds->refined       = PETSC_FALSE;
    119:   ds->extrarow      = PETSC_FALSE;
    120:   ds->ld            = 0;
    121:   ds->l             = 0;
    122:   ds->n             = 0;
    123:   ds->k             = 0;
    124:   ds->t             = 0;
    125:   ds->bs            = 1;
    126:   ds->sc            = NULL;
    127:   ds->pmode         = DS_PARALLEL_REDUNDANT;

    129:   for (i=0;i<DS_NUM_MAT;i++) ds->omat[i] = NULL;
    130:   ds->perm          = NULL;
    131:   ds->data          = NULL;
    132:   ds->scset         = PETSC_FALSE;
    133:   ds->work          = NULL;
    134:   ds->rwork         = NULL;
    135:   ds->iwork         = NULL;
    136:   ds->lwork         = 0;
    137:   ds->lrwork        = 0;
    138:   ds->liwork        = 0;

    140:   *newds = ds;
    141:   PetscFunctionReturn(PETSC_SUCCESS);
    142: }

    144: /*@C
    145:    DSSetOptionsPrefix - Sets the prefix used for searching for all
    146:    DS options in the database.

    148:    Logically Collective

    150:    Input Parameters:
    151: +  ds - the direct solver context
    152: -  prefix - the prefix string to prepend to all DS option requests

    154:    Notes:
    155:    A hyphen (-) must NOT be given at the beginning of the prefix name.
    156:    The first character of all runtime options is AUTOMATICALLY the
    157:    hyphen.

    159:    Level: advanced

    161: .seealso: DSAppendOptionsPrefix()
    162: @*/
    163: PetscErrorCode DSSetOptionsPrefix(DS ds,const char *prefix)
    164: {
    165:   PetscFunctionBegin;
    167:   PetscCall(PetscObjectSetOptionsPrefix((PetscObject)ds,prefix));
    168:   PetscFunctionReturn(PETSC_SUCCESS);
    169: }

    171: /*@C
    172:    DSAppendOptionsPrefix - Appends to the prefix used for searching for all
    173:    DS options in the database.

    175:    Logically Collective

    177:    Input Parameters:
    178: +  ds - the direct solver context
    179: -  prefix - the prefix string to prepend to all DS option requests

    181:    Notes:
    182:    A hyphen (-) must NOT be given at the beginning of the prefix name.
    183:    The first character of all runtime options is AUTOMATICALLY the hyphen.

    185:    Level: advanced

    187: .seealso: DSSetOptionsPrefix()
    188: @*/
    189: PetscErrorCode DSAppendOptionsPrefix(DS ds,const char *prefix)
    190: {
    191:   PetscFunctionBegin;
    193:   PetscCall(PetscObjectAppendOptionsPrefix((PetscObject)ds,prefix));
    194:   PetscFunctionReturn(PETSC_SUCCESS);
    195: }

    197: /*@C
    198:    DSGetOptionsPrefix - Gets the prefix used for searching for all
    199:    DS options in the database.

    201:    Not Collective

    203:    Input Parameters:
    204: .  ds - the direct solver context

    206:    Output Parameters:
    207: .  prefix - pointer to the prefix string used is returned

    209:    Note:
    210:    On the Fortran side, the user should pass in a string 'prefix' of
    211:    sufficient length to hold the prefix.

    213:    Level: advanced

    215: .seealso: DSSetOptionsPrefix(), DSAppendOptionsPrefix()
    216: @*/
    217: PetscErrorCode DSGetOptionsPrefix(DS ds,const char *prefix[])
    218: {
    219:   PetscFunctionBegin;
    221:   PetscAssertPointer(prefix,2);
    222:   PetscCall(PetscObjectGetOptionsPrefix((PetscObject)ds,prefix));
    223:   PetscFunctionReturn(PETSC_SUCCESS);
    224: }

    226: /*@C
    227:    DSSetType - Selects the type for the DS object.

    229:    Logically Collective

    231:    Input Parameters:
    232: +  ds   - the direct solver context
    233: -  type - a known type

    235:    Level: intermediate

    237: .seealso: DSGetType()
    238: @*/
    239: PetscErrorCode DSSetType(DS ds,DSType type)
    240: {
    241:   PetscErrorCode (*r)(DS);
    242:   PetscBool      match;

    244:   PetscFunctionBegin;
    246:   PetscAssertPointer(type,2);

    248:   PetscCall(PetscObjectTypeCompare((PetscObject)ds,type,&match));
    249:   if (match) PetscFunctionReturn(PETSC_SUCCESS);

    251:   PetscCall(PetscFunctionListFind(DSList,type,&r));
    252:   PetscCheck(r,PetscObjectComm((PetscObject)ds),PETSC_ERR_ARG_UNKNOWN_TYPE,"Unable to find requested DS type %s",type);

    254:   PetscCall(PetscMemzero(ds->ops,sizeof(struct _DSOps)));

    256:   PetscCall(PetscObjectChangeTypeName((PetscObject)ds,type));
    257:   PetscCall((*r)(ds));
    258:   PetscFunctionReturn(PETSC_SUCCESS);
    259: }

    261: /*@C
    262:    DSGetType - Gets the DS type name (as a string) from the DS context.

    264:    Not Collective

    266:    Input Parameter:
    267: .  ds - the direct solver context

    269:    Output Parameter:
    270: .  type - name of the direct solver

    272:    Level: intermediate

    274: .seealso: DSSetType()
    275: @*/
    276: PetscErrorCode DSGetType(DS ds,DSType *type)
    277: {
    278:   PetscFunctionBegin;
    280:   PetscAssertPointer(type,2);
    281:   *type = ((PetscObject)ds)->type_name;
    282:   PetscFunctionReturn(PETSC_SUCCESS);
    283: }

    285: /*@
    286:    DSDuplicate - Creates a new direct solver object with the same options as
    287:    an existing one.

    289:    Collective

    291:    Input Parameter:
    292: .  ds - direct solver context

    294:    Output Parameter:
    295: .  dsnew - location to put the new DS

    297:    Notes:
    298:    DSDuplicate() DOES NOT COPY the matrices, and the new DS does not even have
    299:    internal arrays allocated. Use DSAllocate() to use the new DS.

    301:    The sorting criterion options are not copied, see DSSetSlepcSC().

    303:    Level: intermediate

    305: .seealso: DSCreate(), DSAllocate(), DSSetSlepcSC()
    306: @*/
    307: PetscErrorCode DSDuplicate(DS ds,DS *dsnew)
    308: {
    309:   PetscFunctionBegin;
    311:   PetscAssertPointer(dsnew,2);
    312:   PetscCall(DSCreate(PetscObjectComm((PetscObject)ds),dsnew));
    313:   if (((PetscObject)ds)->type_name) PetscCall(DSSetType(*dsnew,((PetscObject)ds)->type_name));
    314:   (*dsnew)->method   = ds->method;
    315:   (*dsnew)->compact  = ds->compact;
    316:   (*dsnew)->refined  = ds->refined;
    317:   (*dsnew)->extrarow = ds->extrarow;
    318:   (*dsnew)->bs       = ds->bs;
    319:   (*dsnew)->pmode    = ds->pmode;
    320:   PetscFunctionReturn(PETSC_SUCCESS);
    321: }

    323: /*@
    324:    DSSetMethod - Selects the method to be used to solve the problem.

    326:    Logically Collective

    328:    Input Parameters:
    329: +  ds   - the direct solver context
    330: -  meth - an index identifying the method

    332:    Options Database Key:
    333: .  -ds_method <meth> - Sets the method

    335:    Level: intermediate

    337: .seealso: DSGetMethod()
    338: @*/
    339: PetscErrorCode DSSetMethod(DS ds,PetscInt meth)
    340: {
    341:   PetscFunctionBegin;
    344:   PetscCheck(meth>=0,PetscObjectComm((PetscObject)ds),PETSC_ERR_ARG_OUTOFRANGE,"The method must be a non-negative integer");
    345:   PetscCheck(meth<=DS_MAX_SOLVE,PetscObjectComm((PetscObject)ds),PETSC_ERR_ARG_OUTOFRANGE,"Too large value for the method");
    346:   ds->method = meth;
    347:   PetscFunctionReturn(PETSC_SUCCESS);
    348: }

    350: /*@
    351:    DSGetMethod - Gets the method currently used in the DS.

    353:    Not Collective

    355:    Input Parameter:
    356: .  ds - the direct solver context

    358:    Output Parameter:
    359: .  meth - identifier of the method

    361:    Level: intermediate

    363: .seealso: DSSetMethod()
    364: @*/
    365: PetscErrorCode DSGetMethod(DS ds,PetscInt *meth)
    366: {
    367:   PetscFunctionBegin;
    369:   PetscAssertPointer(meth,2);
    370:   *meth = ds->method;
    371:   PetscFunctionReturn(PETSC_SUCCESS);
    372: }

    374: /*@
    375:    DSSetParallel - Selects the mode of operation in parallel runs.

    377:    Logically Collective

    379:    Input Parameters:
    380: +  ds    - the direct solver context
    381: -  pmode - the parallel mode

    383:    Options Database Key:
    384: .  -ds_parallel <mode> - Sets the parallel mode, 'redundant', 'synchronized'
    385:    or 'distributed'

    387:    Notes:
    388:    In the 'redundant' parallel mode, all processes will make the computation
    389:    redundantly, starting from the same data, and producing the same result.
    390:    This result may be slightly different in the different processes if using a
    391:    multithreaded BLAS library, which may cause issues in ill-conditioned problems.

    393:    In the 'synchronized' parallel mode, only the first MPI process performs the
    394:    computation and then the computed quantities are broadcast to the other
    395:    processes in the communicator. This communication is not done automatically,
    396:    an explicit call to DSSynchronize() is required.

    398:    The 'distributed' parallel mode can be used in some DS types only, such
    399:    as the contour integral method of DSNEP. In this case, every MPI process
    400:    will be in charge of part of the computation.

    402:    Level: advanced

    404: .seealso: DSSynchronize(), DSGetParallel()
    405: @*/
    406: PetscErrorCode DSSetParallel(DS ds,DSParallelType pmode)
    407: {
    408:   PetscFunctionBegin;
    411:   ds->pmode = pmode;
    412:   PetscFunctionReturn(PETSC_SUCCESS);
    413: }

    415: /*@
    416:    DSGetParallel - Gets the mode of operation in parallel runs.

    418:    Not Collective

    420:    Input Parameter:
    421: .  ds - the direct solver context

    423:    Output Parameter:
    424: .  pmode - the parallel mode

    426:    Level: advanced

    428: .seealso: DSSetParallel()
    429: @*/
    430: PetscErrorCode DSGetParallel(DS ds,DSParallelType *pmode)
    431: {
    432:   PetscFunctionBegin;
    434:   PetscAssertPointer(pmode,2);
    435:   *pmode = ds->pmode;
    436:   PetscFunctionReturn(PETSC_SUCCESS);
    437: }

    439: /*@
    440:    DSSetCompact - Switch to compact storage of matrices.

    442:    Logically Collective

    444:    Input Parameters:
    445: +  ds   - the direct solver context
    446: -  comp - a boolean flag

    448:    Notes:
    449:    Compact storage is used in some DS types such as DSHEP when the matrix
    450:    is tridiagonal. This flag can be used to indicate whether the user
    451:    provides the matrix entries via the compact form (the tridiagonal DS_MAT_T)
    452:    or the non-compact one (DS_MAT_A).

    454:    The default is PETSC_FALSE.

    456:    Level: advanced

    458: .seealso: DSGetCompact()
    459: @*/
    460: PetscErrorCode DSSetCompact(DS ds,PetscBool comp)
    461: {
    462:   PetscFunctionBegin;
    465:   ds->compact = comp;
    466:   PetscFunctionReturn(PETSC_SUCCESS);
    467: }

    469: /*@
    470:    DSGetCompact - Gets the compact storage flag.

    472:    Not Collective

    474:    Input Parameter:
    475: .  ds - the direct solver context

    477:    Output Parameter:
    478: .  comp - the flag

    480:    Level: advanced

    482: .seealso: DSSetCompact()
    483: @*/
    484: PetscErrorCode DSGetCompact(DS ds,PetscBool *comp)
    485: {
    486:   PetscFunctionBegin;
    488:   PetscAssertPointer(comp,2);
    489:   *comp = ds->compact;
    490:   PetscFunctionReturn(PETSC_SUCCESS);
    491: }

    493: /*@
    494:    DSSetExtraRow - Sets a flag to indicate that the matrix has one extra
    495:    row.

    497:    Logically Collective

    499:    Input Parameters:
    500: +  ds  - the direct solver context
    501: -  ext - a boolean flag

    503:    Notes:
    504:    In Krylov methods it is useful that the matrix representing the direct solver
    505:    has one extra row, i.e., has dimension (n+1) x n. If this flag is activated, all
    506:    transformations applied to the right of the matrix also affect this additional
    507:    row. In that case, (n+1) must be less or equal than the leading dimension.

    509:    The default is PETSC_FALSE.

    511:    Level: advanced

    513: .seealso: DSSolve(), DSAllocate(), DSGetExtraRow()
    514: @*/
    515: PetscErrorCode DSSetExtraRow(DS ds,PetscBool ext)
    516: {
    517:   PetscFunctionBegin;
    520:   PetscCheck(!ext || ds->n==0 || ds->n!=ds->ld,PetscObjectComm((PetscObject)ds),PETSC_ERR_ORDER,"Cannot set extra row after setting n=ld");
    521:   ds->extrarow = ext;
    522:   PetscFunctionReturn(PETSC_SUCCESS);
    523: }

    525: /*@
    526:    DSGetExtraRow - Gets the extra row flag.

    528:    Not Collective

    530:    Input Parameter:
    531: .  ds - the direct solver context

    533:    Output Parameter:
    534: .  ext - the flag

    536:    Level: advanced

    538: .seealso: DSSetExtraRow()
    539: @*/
    540: PetscErrorCode DSGetExtraRow(DS ds,PetscBool *ext)
    541: {
    542:   PetscFunctionBegin;
    544:   PetscAssertPointer(ext,2);
    545:   *ext = ds->extrarow;
    546:   PetscFunctionReturn(PETSC_SUCCESS);
    547: }

    549: /*@
    550:    DSSetRefined - Sets a flag to indicate that refined vectors must be
    551:    computed.

    553:    Logically Collective

    555:    Input Parameters:
    556: +  ds  - the direct solver context
    557: -  ref - a boolean flag

    559:    Notes:
    560:    Normally the vectors returned in DS_MAT_X are eigenvectors of the
    561:    projected matrix. With this flag activated, DSVectors() will return
    562:    the right singular vector of the smallest singular value of matrix
    563:    \tilde{A}-theta*I, where \tilde{A} is the extended (n+1)xn matrix
    564:    and theta is the Ritz value. This is used in the refined Ritz
    565:    approximation.

    567:    The default is PETSC_FALSE.

    569:    Level: advanced

    571: .seealso: DSVectors(), DSGetRefined()
    572: @*/
    573: PetscErrorCode DSSetRefined(DS ds,PetscBool ref)
    574: {
    575:   PetscFunctionBegin;
    578:   ds->refined = ref;
    579:   PetscFunctionReturn(PETSC_SUCCESS);
    580: }

    582: /*@
    583:    DSGetRefined - Gets the refined vectors flag.

    585:    Not Collective

    587:    Input Parameter:
    588: .  ds - the direct solver context

    590:    Output Parameter:
    591: .  ref - the flag

    593:    Level: advanced

    595: .seealso: DSSetRefined()
    596: @*/
    597: PetscErrorCode DSGetRefined(DS ds,PetscBool *ref)
    598: {
    599:   PetscFunctionBegin;
    601:   PetscAssertPointer(ref,2);
    602:   *ref = ds->refined;
    603:   PetscFunctionReturn(PETSC_SUCCESS);
    604: }

    606: /*@
    607:    DSSetBlockSize - Sets the block size.

    609:    Logically Collective

    611:    Input Parameters:
    612: +  ds - the direct solver context
    613: -  bs - the block size

    615:    Options Database Key:
    616: .  -ds_block_size <bs> - Sets the block size

    618:    Level: intermediate

    620: .seealso: DSGetBlockSize()
    621: @*/
    622: PetscErrorCode DSSetBlockSize(DS ds,PetscInt bs)
    623: {
    624:   PetscFunctionBegin;
    627:   PetscCheck(bs>0,PetscObjectComm((PetscObject)ds),PETSC_ERR_ARG_OUTOFRANGE,"The block size must be at least one");
    628:   ds->bs = bs;
    629:   PetscFunctionReturn(PETSC_SUCCESS);
    630: }

    632: /*@
    633:    DSGetBlockSize - Gets the block size.

    635:    Not Collective

    637:    Input Parameter:
    638: .  ds - the direct solver context

    640:    Output Parameter:
    641: .  bs - block size

    643:    Level: intermediate

    645: .seealso: DSSetBlockSize()
    646: @*/
    647: PetscErrorCode DSGetBlockSize(DS ds,PetscInt *bs)
    648: {
    649:   PetscFunctionBegin;
    651:   PetscAssertPointer(bs,2);
    652:   *bs = ds->bs;
    653:   PetscFunctionReturn(PETSC_SUCCESS);
    654: }

    656: /*@C
    657:    DSSetSlepcSC - Sets the sorting criterion context.

    659:    Logically Collective

    661:    Input Parameters:
    662: +  ds - the direct solver context
    663: -  sc - a pointer to the sorting criterion context

    665:    Level: developer

    667: .seealso: DSGetSlepcSC(), DSSort()
    668: @*/
    669: PetscErrorCode DSSetSlepcSC(DS ds,SlepcSC sc)
    670: {
    671:   PetscFunctionBegin;
    673:   PetscAssertPointer(sc,2);
    674:   if (ds->sc && !ds->scset) PetscCall(PetscFree(ds->sc));
    675:   ds->sc    = sc;
    676:   ds->scset = PETSC_TRUE;
    677:   PetscFunctionReturn(PETSC_SUCCESS);
    678: }

    680: /*@C
    681:    DSGetSlepcSC - Gets the sorting criterion context.

    683:    Not Collective

    685:    Input Parameter:
    686: .  ds - the direct solver context

    688:    Output Parameters:
    689: .  sc - a pointer to the sorting criterion context

    691:    Level: developer

    693: .seealso: DSSetSlepcSC(), DSSort()
    694: @*/
    695: PetscErrorCode DSGetSlepcSC(DS ds,SlepcSC *sc)
    696: {
    697:   PetscFunctionBegin;
    699:   PetscAssertPointer(sc,2);
    700:   if (!ds->sc) PetscCall(PetscNew(&ds->sc));
    701:   *sc = ds->sc;
    702:   PetscFunctionReturn(PETSC_SUCCESS);
    703: }

    705: /*@
    706:    DSSetFromOptions - Sets DS options from the options database.

    708:    Collective

    710:    Input Parameters:
    711: .  ds - the direct solver context

    713:    Notes:
    714:    To see all options, run your program with the -help option.

    716:    Level: beginner

    718: .seealso: DSSetOptionsPrefix()
    719: @*/
    720: PetscErrorCode DSSetFromOptions(DS ds)
    721: {
    722:   PetscInt       bs,meth;
    723:   PetscBool      flag;
    724:   DSParallelType pmode;

    726:   PetscFunctionBegin;
    728:   PetscCall(DSRegisterAll());
    729:   /* Set default type (we do not allow changing it with -ds_type) */
    730:   if (!((PetscObject)ds)->type_name) PetscCall(DSSetType(ds,DSNHEP));
    731:   PetscObjectOptionsBegin((PetscObject)ds);

    733:     PetscCall(PetscOptionsInt("-ds_block_size","Block size for the dense system solver","DSSetBlockSize",ds->bs,&bs,&flag));
    734:     if (flag) PetscCall(DSSetBlockSize(ds,bs));

    736:     PetscCall(PetscOptionsInt("-ds_method","Method to be used for the dense system","DSSetMethod",ds->method,&meth,&flag));
    737:     if (flag) PetscCall(DSSetMethod(ds,meth));

    739:     PetscCall(PetscOptionsEnum("-ds_parallel","Operation mode in parallel runs","DSSetParallel",DSParallelTypes,(PetscEnum)ds->pmode,(PetscEnum*)&pmode,&flag));
    740:     if (flag) PetscCall(DSSetParallel(ds,pmode));

    742:     PetscTryTypeMethod(ds,setfromoptions,PetscOptionsObject);
    743:     PetscCall(PetscObjectProcessOptionsHandlers((PetscObject)ds,PetscOptionsObject));
    744:   PetscOptionsEnd();
    745:   PetscFunctionReturn(PETSC_SUCCESS);
    746: }

    748: /*@C
    749:    DSView - Prints the DS data structure.

    751:    Collective

    753:    Input Parameters:
    754: +  ds - the direct solver context
    755: -  viewer - optional visualization context

    757:    Note:
    758:    The available visualization contexts include
    759: +     PETSC_VIEWER_STDOUT_SELF - standard output (default)
    760: -     PETSC_VIEWER_STDOUT_WORLD - synchronized standard
    761:          output where only the first processor opens
    762:          the file.  All other processors send their
    763:          data to the first processor to print.

    765:    The user can open an alternative visualization context with
    766:    PetscViewerASCIIOpen() - output to a specified file.

    768:    Level: beginner

    770: .seealso: DSViewMat()
    771: @*/
    772: PetscErrorCode DSView(DS ds,PetscViewer viewer)
    773: {
    774:   PetscBool         isascii;
    775:   PetscViewerFormat format;
    776:   PetscMPIInt       size;

    778:   PetscFunctionBegin;
    780:   if (!viewer) PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)ds),&viewer));
    782:   PetscCheckSameComm(ds,1,viewer,2);
    783:   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii));
    784:   if (isascii) {
    785:     PetscCall(PetscViewerGetFormat(viewer,&format));
    786:     PetscCall(PetscObjectPrintClassNamePrefixType((PetscObject)ds,viewer));
    787:     PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)ds),&size));
    788:     if (size>1) PetscCall(PetscViewerASCIIPrintf(viewer,"  parallel operation mode: %s\n",DSParallelTypes[ds->pmode]));
    789:     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
    790:       PetscCall(PetscViewerASCIIPrintf(viewer,"  current state: %s\n",DSStateTypes[ds->state]));
    791:       PetscCall(PetscViewerASCIIPrintf(viewer,"  dimensions: ld=%" PetscInt_FMT ", n=%" PetscInt_FMT ", l=%" PetscInt_FMT ", k=%" PetscInt_FMT,ds->ld,ds->n,ds->l,ds->k));
    792:       if (ds->state==DS_STATE_TRUNCATED) PetscCall(PetscViewerASCIIPrintf(viewer,", t=%" PetscInt_FMT "\n",ds->t));
    793:       else PetscCall(PetscViewerASCIIPrintf(viewer,"\n"));
    794:       PetscCall(PetscViewerASCIIPrintf(viewer,"  flags:%s%s%s\n",ds->compact?" compact":"",ds->extrarow?" extrarow":"",ds->refined?" refined":""));
    795:     }
    796:     PetscCall(PetscViewerASCIIPushTab(viewer));
    797:     PetscTryTypeMethod(ds,view,viewer);
    798:     PetscCall(PetscViewerASCIIPopTab(viewer));
    799:   }
    800:   PetscFunctionReturn(PETSC_SUCCESS);
    801: }

    803: /*@C
    804:    DSViewFromOptions - View from options

    806:    Collective

    808:    Input Parameters:
    809: +  ds   - the direct solver context
    810: .  obj  - optional object
    811: -  name - command line option

    813:    Level: intermediate

    815: .seealso: DSView(), DSCreate()
    816: @*/
    817: PetscErrorCode DSViewFromOptions(DS ds,PetscObject obj,const char name[])
    818: {
    819:   PetscFunctionBegin;
    821:   PetscCall(PetscObjectViewFromOptions((PetscObject)ds,obj,name));
    822:   PetscFunctionReturn(PETSC_SUCCESS);
    823: }

    825: /*@
    826:    DSAllocate - Allocates memory for internal storage or matrices in DS.

    828:    Logically Collective

    830:    Input Parameters:
    831: +  ds - the direct solver context
    832: -  ld - leading dimension (maximum allowed dimension for the matrices, including
    833:         the extra row if present)

    835:    Note:
    836:    If the leading dimension is different from a previously set value, then
    837:    all matrices are destroyed with DSReset().

    839:    Level: intermediate

    841: .seealso: DSGetLeadingDimension(), DSSetDimensions(), DSSetExtraRow(), DSReset()
    842: @*/
    843: PetscErrorCode DSAllocate(DS ds,PetscInt ld)
    844: {
    845:   PetscFunctionBegin;
    849:   PetscCheck(ld>0,PetscObjectComm((PetscObject)ds),PETSC_ERR_ARG_OUTOFRANGE,"Leading dimension should be at least one");
    850:   if (ld!=ds->ld) {
    851:     PetscCall(PetscInfo(ds,"Allocating memory with leading dimension=%" PetscInt_FMT "\n",ld));
    852:     PetscCall(DSReset(ds));
    853:     ds->ld = ld;
    854:     PetscUseTypeMethod(ds,allocate,ld);
    855:   }
    856:   PetscFunctionReturn(PETSC_SUCCESS);
    857: }

    859: /*@
    860:    DSReset - Resets the DS context to the initial state.

    862:    Collective

    864:    Input Parameter:
    865: .  ds - the direct solver context

    867:    Note:
    868:    All data structures with size depending on the leading dimension
    869:    of DSAllocate() are released.

    871:    Level: advanced

    873: .seealso: DSDestroy(), DSAllocate()
    874: @*/
    875: PetscErrorCode DSReset(DS ds)
    876: {
    877:   PetscInt       i;

    879:   PetscFunctionBegin;
    881:   if (!ds) PetscFunctionReturn(PETSC_SUCCESS);
    882:   ds->state    = DS_STATE_RAW;
    883:   ds->ld       = 0;
    884:   ds->l        = 0;
    885:   ds->n        = 0;
    886:   ds->k        = 0;
    887:   for (i=0;i<DS_NUM_MAT;i++) PetscCall(MatDestroy(&ds->omat[i]));
    888:   PetscCall(PetscFree(ds->perm));
    889:   PetscFunctionReturn(PETSC_SUCCESS);
    890: }

    892: /*@C
    893:    DSDestroy - Destroys DS context that was created with DSCreate().

    895:    Collective

    897:    Input Parameter:
    898: .  ds - the direct solver context

    900:    Level: beginner

    902: .seealso: DSCreate()
    903: @*/
    904: PetscErrorCode DSDestroy(DS *ds)
    905: {
    906:   PetscFunctionBegin;
    907:   if (!*ds) PetscFunctionReturn(PETSC_SUCCESS);
    909:   if (--((PetscObject)(*ds))->refct > 0) { *ds = NULL; PetscFunctionReturn(PETSC_SUCCESS); }
    910:   PetscCall(DSReset(*ds));
    911:   PetscTryTypeMethod(*ds,destroy);
    912:   PetscCall(PetscFree((*ds)->work));
    913:   PetscCall(PetscFree((*ds)->rwork));
    914:   PetscCall(PetscFree((*ds)->iwork));
    915:   if (!(*ds)->scset) PetscCall(PetscFree((*ds)->sc));
    916:   PetscCall(PetscHeaderDestroy(ds));
    917:   PetscFunctionReturn(PETSC_SUCCESS);
    918: }

    920: /*@C
    921:    DSRegister - Adds a direct solver to the DS package.

    923:    Not Collective

    925:    Input Parameters:
    926: +  name - name of a new user-defined DS
    927: -  function - routine to create context

    929:    Notes:
    930:    DSRegister() may be called multiple times to add several user-defined
    931:    direct solvers.

    933:    Level: advanced

    935: .seealso: DSRegisterAll()
    936: @*/
    937: PetscErrorCode DSRegister(const char *name,PetscErrorCode (*function)(DS))
    938: {
    939:   PetscFunctionBegin;
    940:   PetscCall(DSInitializePackage());
    941:   PetscCall(PetscFunctionListAdd(&DSList,name,function));
    942:   PetscFunctionReturn(PETSC_SUCCESS);
    943: }

    945: SLEPC_EXTERN PetscErrorCode DSCreate_HEP(DS);
    946: SLEPC_EXTERN PetscErrorCode DSCreate_NHEP(DS);
    947: SLEPC_EXTERN PetscErrorCode DSCreate_GHEP(DS);
    948: SLEPC_EXTERN PetscErrorCode DSCreate_GHIEP(DS);
    949: SLEPC_EXTERN PetscErrorCode DSCreate_GNHEP(DS);
    950: SLEPC_EXTERN PetscErrorCode DSCreate_NHEPTS(DS);
    951: SLEPC_EXTERN PetscErrorCode DSCreate_SVD(DS);
    952: SLEPC_EXTERN PetscErrorCode DSCreate_HSVD(DS);
    953: SLEPC_EXTERN PetscErrorCode DSCreate_GSVD(DS);
    954: SLEPC_EXTERN PetscErrorCode DSCreate_PEP(DS);
    955: SLEPC_EXTERN PetscErrorCode DSCreate_NEP(DS);

    957: /*@C
    958:    DSRegisterAll - Registers all of the direct solvers in the DS package.

    960:    Not Collective

    962:    Level: advanced

    964: .seealso: DSRegister()
    965: @*/
    966: PetscErrorCode DSRegisterAll(void)
    967: {
    968:   PetscFunctionBegin;
    969:   if (DSRegisterAllCalled) PetscFunctionReturn(PETSC_SUCCESS);
    970:   DSRegisterAllCalled = PETSC_TRUE;
    971:   PetscCall(DSRegister(DSHEP,DSCreate_HEP));
    972:   PetscCall(DSRegister(DSNHEP,DSCreate_NHEP));
    973:   PetscCall(DSRegister(DSGHEP,DSCreate_GHEP));
    974:   PetscCall(DSRegister(DSGHIEP,DSCreate_GHIEP));
    975:   PetscCall(DSRegister(DSGNHEP,DSCreate_GNHEP));
    976:   PetscCall(DSRegister(DSNHEPTS,DSCreate_NHEPTS));
    977:   PetscCall(DSRegister(DSSVD,DSCreate_SVD));
    978:   PetscCall(DSRegister(DSHSVD,DSCreate_HSVD));
    979:   PetscCall(DSRegister(DSGSVD,DSCreate_GSVD));
    980:   PetscCall(DSRegister(DSPEP,DSCreate_PEP));
    981:   PetscCall(DSRegister(DSNEP,DSCreate_NEP));
    982:   PetscFunctionReturn(PETSC_SUCCESS);
    983: }