Date: 2021-02-01T14:42:05+00:00

Actual source code: svdopts.c
slepc-3.14.2 2021-02-01
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      1: /*
      2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
      4:    Copyright (c) 2002-2020, 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:    SVD routines for setting solver options
     12: */

     14: #include <slepc/private/svdimpl.h>
     15: #include <petscdraw.h>

     17: /*@
     18:    SVDSetImplicitTranspose - Indicates how to handle the transpose of the matrix
     19:    associated with the singular value problem.

     21:    Logically Collective on svd

     23:    Input Parameters:
     24: +  svd  - the singular value solver context
     25: -  impl - how to handle the transpose (implicitly or not)

     27:    Options Database Key:
     28: .  -svd_implicittranspose - Activate the implicit transpose mode.

     30:    Notes:
     31:    By default, the transpose of the matrix is explicitly built (if the matrix
     32:    has defined the MatTranspose operation).

     34:    If this flag is set to true, the solver does not build the transpose, but
     35:    handles it implicitly via MatMultTranspose() (or MatMultHermitianTranspose()
     36:    in the complex case) operations. This is likely to be more inefficient
     37:    than the default behaviour, both in sequential and in parallel, but
     38:    requires less storage.

     40:    Level: advanced

     42: .seealso: SVDGetImplicitTranspose(), SVDSolve(), SVDSetOperator()
     43: @*/
     44: PetscErrorCode SVDSetImplicitTranspose(SVD svd,PetscBool impl)
     45: {
     49:   if (svd->impltrans!=impl) {
     50:     svd->impltrans = impl;
     51:     svd->state     = SVD_STATE_INITIAL;
     52:   }
     53:   return(0);
     54: }

     56: /*@
     57:    SVDGetImplicitTranspose - Gets the mode used to handle the transpose
     58:    of the matrix associated with the singular value problem.

     60:    Not Collective

     62:    Input Parameter:
     63: .  svd  - the singular value solver context

     65:    Output Parameter:
     66: .  impl - how to handle the transpose (implicitly or not)

     68:    Level: advanced

     70: .seealso: SVDSetImplicitTranspose(), SVDSolve(), SVDSetOperator()
     71: @*/
     72: PetscErrorCode SVDGetImplicitTranspose(SVD svd,PetscBool *impl)
     73: {
     77:   *impl = svd->impltrans;
     78:   return(0);
     79: }

     81: /*@
     82:    SVDSetTolerances - Sets the tolerance and maximum
     83:    iteration count used by the default SVD convergence testers.

     85:    Logically Collective on svd

     87:    Input Parameters:
     88: +  svd - the singular value solver context
     89: .  tol - the convergence tolerance
     90: -  maxits - maximum number of iterations to use

     92:    Options Database Keys:
     93: +  -svd_tol <tol> - Sets the convergence tolerance
     94: -  -svd_max_it <maxits> - Sets the maximum number of iterations allowed

     96:    Note:
     97:    Use PETSC_DEFAULT for either argument to assign a reasonably good value.

     99:    Level: intermediate

    101: .seealso: SVDGetTolerances()
    102: @*/
    103: PetscErrorCode SVDSetTolerances(SVD svd,PetscReal tol,PetscInt maxits)
    104: {
    109:   if (tol == PETSC_DEFAULT) {
    110:     svd->tol   = PETSC_DEFAULT;
    111:     svd->state = SVD_STATE_INITIAL;
    112:   } else {
    113:     if (tol <= 0.0) SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of tol. Must be > 0");
    114:     svd->tol = tol;
    115:   }
    116:   if (maxits == PETSC_DEFAULT || maxits == PETSC_DECIDE) {
    117:     svd->max_it = PETSC_DEFAULT;
    118:     svd->state  = SVD_STATE_INITIAL;
    119:   } else {
    120:     if (maxits <= 0) SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of maxits. Must be > 0");
    121:     svd->max_it = maxits;
    122:   }
    123:   return(0);
    124: }

    126: /*@C
    127:    SVDGetTolerances - Gets the tolerance and maximum
    128:    iteration count used by the default SVD convergence tests.

    130:    Not Collective

    132:    Input Parameter:
    133: .  svd - the singular value solver context

    135:    Output Parameters:
    136: +  tol - the convergence tolerance
    137: -  maxits - maximum number of iterations

    139:    Notes:
    140:    The user can specify NULL for any parameter that is not needed.

    142:    Level: intermediate

    144: .seealso: SVDSetTolerances()
    145: @*/
    146: PetscErrorCode SVDGetTolerances(SVD svd,PetscReal *tol,PetscInt *maxits)
    147: {
    150:   if (tol)    *tol    = svd->tol;
    151:   if (maxits) *maxits = svd->max_it;
    152:   return(0);
    153: }

    155: /*@
    156:    SVDSetDimensions - Sets the number of singular values to compute
    157:    and the dimension of the subspace.

    159:    Logically Collective on svd

    161:    Input Parameters:
    162: +  svd - the singular value solver context
    163: .  nsv - number of singular values to compute
    164: .  ncv - the maximum dimension of the subspace to be used by the solver
    165: -  mpd - the maximum dimension allowed for the projected problem

    167:    Options Database Keys:
    168: +  -svd_nsv <nsv> - Sets the number of singular values
    169: .  -svd_ncv <ncv> - Sets the dimension of the subspace
    170: -  -svd_mpd <mpd> - Sets the maximum projected dimension

    172:    Notes:
    173:    Use PETSC_DEFAULT for ncv and mpd to assign a reasonably good value, which is
    174:    dependent on the solution method and the number of singular values required.

    176:    The parameters ncv and mpd are intimately related, so that the user is advised
    177:    to set one of them at most. Normal usage is that
    178:    (a) in cases where nsv is small, the user sets ncv (a reasonable default is 2*nsv); and
    179:    (b) in cases where nsv is large, the user sets mpd.

    181:    The value of ncv should always be between nsv and (nsv+mpd), typically
    182:    ncv=nsv+mpd. If nsv is not too large, mpd=nsv is a reasonable choice, otherwise
    183:    a smaller value should be used.

    185:    Level: intermediate

    187: .seealso: SVDGetDimensions()
    188: @*/
    189: PetscErrorCode SVDSetDimensions(SVD svd,PetscInt nsv,PetscInt ncv,PetscInt mpd)
    190: {
    196:   if (nsv<1) SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of nsv. Must be > 0");
    197:   svd->nsv = nsv;
    198:   if (ncv == PETSC_DEFAULT || ncv == PETSC_DECIDE) {
    199:     svd->ncv = PETSC_DEFAULT;
    200:   } else {
    201:     if (ncv<1) SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of ncv. Must be > 0");
    202:     svd->ncv = ncv;
    203:   }
    204:   if (mpd == PETSC_DECIDE || mpd == PETSC_DEFAULT) {
    205:     svd->mpd = PETSC_DEFAULT;
    206:   } else {
    207:     if (mpd<1) SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Illegal value of mpd. Must be > 0");
    208:     svd->mpd = mpd;
    209:   }
    210:   svd->state = SVD_STATE_INITIAL;
    211:   return(0);
    212: }

    214: /*@C
    215:    SVDGetDimensions - Gets the number of singular values to compute
    216:    and the dimension of the subspace.

    218:    Not Collective

    220:    Input Parameter:
    221: .  svd - the singular value context

    223:    Output Parameters:
    224: +  nsv - number of singular values to compute
    225: .  ncv - the maximum dimension of the subspace to be used by the solver
    226: -  mpd - the maximum dimension allowed for the projected problem

    228:    Notes:
    229:    The user can specify NULL for any parameter that is not needed.

    231:    Level: intermediate

    233: .seealso: SVDSetDimensions()
    234: @*/
    235: PetscErrorCode SVDGetDimensions(SVD svd,PetscInt *nsv,PetscInt *ncv,PetscInt *mpd)
    236: {
    239:   if (nsv) *nsv = svd->nsv;
    240:   if (ncv) *ncv = svd->ncv;
    241:   if (mpd) *mpd = svd->mpd;
    242:   return(0);
    243: }

    245: /*@
    246:     SVDSetWhichSingularTriplets - Specifies which singular triplets are
    247:     to be sought.

    249:     Logically Collective on svd

    251:     Input Parameter:
    252: .   svd - singular value solver context obtained from SVDCreate()

    254:     Output Parameter:
    255: .   which - which singular triplets are to be sought

    257:     Possible values:
    258:     The parameter 'which' can have one of these values

    260: +     SVD_LARGEST  - largest singular values
    261: -     SVD_SMALLEST - smallest singular values

    263:     Options Database Keys:
    264: +   -svd_largest  - Sets largest singular values
    265: -   -svd_smallest - Sets smallest singular values

    267:     Level: intermediate

    269: .seealso: SVDGetWhichSingularTriplets(), SVDWhich
    270: @*/
    271: PetscErrorCode SVDSetWhichSingularTriplets(SVD svd,SVDWhich which)
    272: {
    276:   switch (which) {
    277:     case SVD_LARGEST:
    278:     case SVD_SMALLEST:
    279:       if (svd->which != which) {
    280:         svd->state = SVD_STATE_INITIAL;
    281:         svd->which = which;
    282:       }
    283:       break;
    284:   default:
    285:     SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'which' parameter");
    286:   }
    287:   return(0);
    288: }

    290: /*@
    291:     SVDGetWhichSingularTriplets - Returns which singular triplets are
    292:     to be sought.

    294:     Not Collective

    296:     Input Parameter:
    297: .   svd - singular value solver context obtained from SVDCreate()

    299:     Output Parameter:
    300: .   which - which singular triplets are to be sought

    302:     Notes:
    303:     See SVDSetWhichSingularTriplets() for possible values of which

    305:     Level: intermediate

    307: .seealso: SVDSetWhichSingularTriplets(), SVDWhich
    308: @*/
    309: PetscErrorCode SVDGetWhichSingularTriplets(SVD svd,SVDWhich *which)
    310: {
    314:   *which = svd->which;
    315:   return(0);
    316: }

    318: /*@C
    319:    SVDSetConvergenceTestFunction - Sets a function to compute the error estimate
    320:    used in the convergence test.

    322:    Logically Collective on svd

    324:    Input Parameters:
    325: +  svd     - singular value solver context obtained from SVDCreate()
    326: .  func    - a pointer to the convergence test function
    327: .  ctx     - context for private data for the convergence routine (may be null)
    328: -  destroy - a routine for destroying the context (may be null)

    330:    Calling Sequence of func:
    331: $   func(SVD svd,PetscReal sigma,PetscReal res,PetscReal *errest,void *ctx)

    333: +   svd    - singular value solver context obtained from SVDCreate()
    334: .   sigma  - computed singular value
    335: .   res    - residual norm associated to the singular triplet
    336: .   errest - (output) computed error estimate
    337: -   ctx    - optional context, as set by SVDSetConvergenceTestFunction()

    339:    Note:
    340:    If the error estimate returned by the convergence test function is less than
    341:    the tolerance, then the singular value is accepted as converged.

    343:    Level: advanced

    345: .seealso: SVDSetConvergenceTest(), SVDSetTolerances()
    346: @*/
    347: PetscErrorCode SVDSetConvergenceTestFunction(SVD svd,PetscErrorCode (*func)(SVD,PetscReal,PetscReal,PetscReal*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
    348: {

    353:   if (svd->convergeddestroy) {
    354:     (*svd->convergeddestroy)(svd->convergedctx);
    355:   }
    356:   svd->convergeduser    = func;
    357:   svd->convergeddestroy = destroy;
    358:   svd->convergedctx     = ctx;
    359:   if (func == SVDConvergedRelative) svd->conv = SVD_CONV_REL;
    360:   else if (func == SVDConvergedAbsolute) svd->conv = SVD_CONV_ABS;
    361:   else {
    362:     svd->conv      = SVD_CONV_USER;
    363:     svd->converged = svd->convergeduser;
    364:   }
    365:   return(0);
    366: }

    368: /*@
    369:    SVDSetConvergenceTest - Specifies how to compute the error estimate
    370:    used in the convergence test.

    372:    Logically Collective on svd

    374:    Input Parameters:
    375: +  svd  - singular value solver context obtained from SVDCreate()
    376: -  conv - the type of convergence test

    378:    Options Database Keys:
    379: +  -svd_conv_abs  - Sets the absolute convergence test
    380: .  -svd_conv_rel  - Sets the convergence test relative to the singular value
    381: -  -svd_conv_user - Selects the user-defined convergence test

    383:    Note:
    384:    The parameter 'conv' can have one of these values
    385: +     SVD_CONV_ABS  - absolute error ||r||
    386: .     SVD_CONV_REL  - error relative to the singular value l, ||r||/sigma
    387: -     SVD_CONV_USER - function set by SVDSetConvergenceTestFunction()

    389:    Level: intermediate

    391: .seealso: SVDGetConvergenceTest(), SVDSetConvergenceTestFunction(), SVDSetStoppingTest(), SVDConv
    392: @*/
    393: PetscErrorCode SVDSetConvergenceTest(SVD svd,SVDConv conv)
    394: {
    398:   switch (conv) {
    399:     case SVD_CONV_ABS:  svd->converged = SVDConvergedAbsolute; break;
    400:     case SVD_CONV_REL:  svd->converged = SVDConvergedRelative; break;
    401:     case SVD_CONV_USER:
    402:       if (!svd->convergeduser) SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ORDER,"Must call SVDSetConvergenceTestFunction() first");
    403:       svd->converged = svd->convergeduser;
    404:       break;
    405:     default:
    406:       SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'conv' value");
    407:   }
    408:   svd->conv = conv;
    409:   return(0);
    410: }

    412: /*@
    413:    SVDGetConvergenceTest - Gets the method used to compute the error estimate
    414:    used in the convergence test.

    416:    Not Collective

    418:    Input Parameters:
    419: .  svd   - singular value solver context obtained from SVDCreate()

    421:    Output Parameters:
    422: .  conv  - the type of convergence test

    424:    Level: intermediate

    426: .seealso: SVDSetConvergenceTest(), SVDConv
    427: @*/
    428: PetscErrorCode SVDGetConvergenceTest(SVD svd,SVDConv *conv)
    429: {
    433:   *conv = svd->conv;
    434:   return(0);
    435: }

    437: /*@C
    438:    SVDSetStoppingTestFunction - Sets a function to decide when to stop the outer
    439:    iteration of the singular value solver.

    441:    Logically Collective on svd

    443:    Input Parameters:
    444: +  svd     - singular value solver context obtained from SVDCreate()
    445: .  func    - pointer to the stopping test function
    446: .  ctx     - context for private data for the stopping routine (may be null)
    447: -  destroy - a routine for destroying the context (may be null)

    449:    Calling Sequence of func:
    450: $   func(SVD svd,PetscInt its,PetscInt max_it,PetscInt nconv,PetscInt nsv,SVDConvergedReason *reason,void *ctx)

    452: +   svd    - singular value solver context obtained from SVDCreate()
    453: .   its    - current number of iterations
    454: .   max_it - maximum number of iterations
    455: .   nconv  - number of currently converged singular triplets
    456: .   nsv    - number of requested singular triplets
    457: .   reason - (output) result of the stopping test
    458: -   ctx    - optional context, as set by SVDSetStoppingTestFunction()

    460:    Note:
    461:    Normal usage is to first call the default routine SVDStoppingBasic() and then
    462:    set reason to SVD_CONVERGED_USER if some user-defined conditions have been
    463:    met. To let the singular value solver continue iterating, the result must be
    464:    left as SVD_CONVERGED_ITERATING.

    466:    Level: advanced

    468: .seealso: SVDSetStoppingTest(), SVDStoppingBasic()
    469: @*/
    470: PetscErrorCode SVDSetStoppingTestFunction(SVD svd,PetscErrorCode (*func)(SVD,PetscInt,PetscInt,PetscInt,PetscInt,SVDConvergedReason*,void*),void* ctx,PetscErrorCode (*destroy)(void*))
    471: {

    476:   if (svd->stoppingdestroy) {
    477:     (*svd->stoppingdestroy)(svd->stoppingctx);
    478:   }
    479:   svd->stoppinguser    = func;
    480:   svd->stoppingdestroy = destroy;
    481:   svd->stoppingctx     = ctx;
    482:   if (func == SVDStoppingBasic) svd->stop = SVD_STOP_BASIC;
    483:   else {
    484:     svd->stop     = SVD_STOP_USER;
    485:     svd->stopping = svd->stoppinguser;
    486:   }
    487:   return(0);
    488: }

    490: /*@
    491:    SVDSetStoppingTest - Specifies how to decide the termination of the outer
    492:    loop of the singular value solver.

    494:    Logically Collective on svd

    496:    Input Parameters:
    497: +  svd  - singular value solver context obtained from SVDCreate()
    498: -  stop - the type of stopping test

    500:    Options Database Keys:
    501: +  -svd_stop_basic - Sets the default stopping test
    502: -  -svd_stop_user  - Selects the user-defined stopping test

    504:    Note:
    505:    The parameter 'stop' can have one of these values
    506: +     SVD_STOP_BASIC - default stopping test
    507: -     SVD_STOP_USER  - function set by SVDSetStoppingTestFunction()

    509:    Level: advanced

    511: .seealso: SVDGetStoppingTest(), SVDSetStoppingTestFunction(), SVDSetConvergenceTest(), SVDStop
    512: @*/
    513: PetscErrorCode SVDSetStoppingTest(SVD svd,SVDStop stop)
    514: {
    518:   switch (stop) {
    519:     case SVD_STOP_BASIC: svd->stopping = SVDStoppingBasic; break;
    520:     case SVD_STOP_USER:
    521:       if (!svd->stoppinguser) SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ORDER,"Must call SVDSetStoppingTestFunction() first");
    522:       svd->stopping = svd->stoppinguser;
    523:       break;
    524:     default:
    525:       SETERRQ(PetscObjectComm((PetscObject)svd),PETSC_ERR_ARG_OUTOFRANGE,"Invalid 'stop' value");
    526:   }
    527:   svd->stop = stop;
    528:   return(0);
    529: }

    531: /*@
    532:    SVDGetStoppingTest - Gets the method used to decide the termination of the outer
    533:    loop of the singular value solver.

    535:    Not Collective

    537:    Input Parameters:
    538: .  svd   - singular value solver context obtained from SVDCreate()

    540:    Output Parameters:
    541: .  stop  - the type of stopping test

    543:    Level: advanced

    545: .seealso: SVDSetStoppingTest(), SVDStop
    546: @*/
    547: PetscErrorCode SVDGetStoppingTest(SVD svd,SVDStop *stop)
    548: {
    552:   *stop = svd->stop;
    553:   return(0);
    554: }

    556: /*@C
    557:    SVDMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type
    558:    indicated by the user.

    560:    Collective on svd

    562:    Input Parameters:
    563: +  svd      - the singular value solver context
    564: .  name     - the monitor option name
    565: .  help     - message indicating what monitoring is done
    566: .  manual   - manual page for the monitor
    567: .  monitor  - the monitor function, whose context is a PetscViewerAndFormat
    568: -  trackall - whether this monitor tracks all singular values or not

    570:    Level: developer

    572: .seealso: SVDMonitorSet(), SVDSetTrackAll(), SVDConvMonitorSetFromOptions()
    573: @*/
    574: PetscErrorCode SVDMonitorSetFromOptions(SVD svd,const char name[],const char help[],const char manual[],PetscErrorCode (*monitor)(SVD,PetscInt,PetscInt,PetscReal*,PetscReal*,PetscInt,PetscViewerAndFormat*),PetscBool trackall)
    575: {
    576:   PetscErrorCode       ierr;
    577:   PetscBool            flg;
    578:   PetscViewer          viewer;
    579:   PetscViewerFormat    format;
    580:   PetscViewerAndFormat *vf;

    583:   PetscOptionsGetViewer(PetscObjectComm((PetscObject)svd),((PetscObject)svd)->options,((PetscObject)svd)->prefix,name,&viewer,&format,&flg);
    584:   if (flg) {
    585:     PetscViewerAndFormatCreate(viewer,format,&vf);
    586:     PetscObjectDereference((PetscObject)viewer);
    587:     SVDMonitorSet(svd,(PetscErrorCode (*)(SVD,PetscInt,PetscInt,PetscReal*,PetscReal*,PetscInt,void*))monitor,vf,(PetscErrorCode (*)(void**))PetscViewerAndFormatDestroy);
    588:     if (trackall) {
    589:       SVDSetTrackAll(svd,PETSC_TRUE);
    590:     }
    591:   }
    592:   return(0);
    593: }

    595: /*@C
    596:    SVDConvMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type
    597:    indicated by the user (for monitors that only show iteration numbers of convergence).

    599:    Collective on svd

    601:    Input Parameters:
    602: +  svd      - the singular value solver context
    603: .  name     - the monitor option name
    604: .  help     - message indicating what monitoring is done
    605: .  manual   - manual page for the monitor
    606: -  monitor  - the monitor function, whose context is a SlepcConvMonitor

    608:    Level: developer

    610: .seealso: SVDMonitorSet(), SVDMonitorSetFromOptions()
    611: @*/
    612: PetscErrorCode SVDConvMonitorSetFromOptions(SVD svd,const char name[],const char help[],const char manual[],PetscErrorCode (*monitor)(SVD,PetscInt,PetscInt,PetscReal*,PetscReal*,PetscInt,SlepcConvMonitor))
    613: {
    614:   PetscErrorCode    ierr;
    615:   PetscBool         flg;
    616:   PetscViewer       viewer;
    617:   PetscViewerFormat format;
    618:   SlepcConvMonitor  ctx;

    621:   PetscOptionsGetViewer(PetscObjectComm((PetscObject)svd),((PetscObject)svd)->options,((PetscObject)svd)->prefix,name,&viewer,&format,&flg);
    622:   if (flg) {
    623:     SlepcConvMonitorCreate(viewer,format,&ctx);
    624:     PetscObjectDereference((PetscObject)viewer);
    625:     SVDMonitorSet(svd,(PetscErrorCode (*)(SVD,PetscInt,PetscInt,PetscReal*,PetscReal*,PetscInt,void*))monitor,ctx,(PetscErrorCode (*)(void**))SlepcConvMonitorDestroy);
    626:   }
    627:   return(0);
    628: }

    630: /*@
    631:    SVDSetFromOptions - Sets SVD options from the options database.
    632:    This routine must be called before SVDSetUp() if the user is to be
    633:    allowed to set the solver type.

    635:    Collective on svd

    637:    Input Parameters:
    638: .  svd - the singular value solver context

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

    643:    Level: beginner

    645: .seealso:
    646: @*/
    647: PetscErrorCode SVDSetFromOptions(SVD svd)
    648: {
    650:   char           type[256];
    651:   PetscBool      set,flg,val,flg1,flg2,flg3;
    652:   PetscInt       i,j,k;
    653:   PetscReal      r;
    654:   PetscDrawLG    lg;

    658:   SVDRegisterAll();
    659:   PetscObjectOptionsBegin((PetscObject)svd);
    660:     PetscOptionsFList("-svd_type","SVD solver method","SVDSetType",SVDList,(char*)(((PetscObject)svd)->type_name?((PetscObject)svd)->type_name:SVDCROSS),type,sizeof(type),&flg);
    661:     if (flg) {
    662:       SVDSetType(svd,type);
    663:     } else if (!((PetscObject)svd)->type_name) {
    664:       SVDSetType(svd,SVDCROSS);
    665:     }

    667:     PetscOptionsBool("-svd_implicittranspose","Handle matrix transpose implicitly","SVDSetImplicitTranspose",svd->impltrans,&val,&flg);
    668:     if (flg) { SVDSetImplicitTranspose(svd,val); }

    670:     i = svd->max_it;
    671:     PetscOptionsInt("-svd_max_it","Maximum number of iterations","SVDSetTolerances",svd->max_it,&i,&flg1);
    672:     r = svd->tol;
    673:     PetscOptionsReal("-svd_tol","Tolerance","SVDSetTolerances",svd->tol==PETSC_DEFAULT?SLEPC_DEFAULT_TOL:svd->tol,&r,&flg2);
    674:     if (flg1 || flg2) { SVDSetTolerances(svd,r,i); }

    676:     PetscOptionsBoolGroupBegin("-svd_conv_rel","Relative error convergence test","SVDSetConvergenceTest",&flg);
    677:     if (flg) { SVDSetConvergenceTest(svd,SVD_CONV_REL); }
    678:     PetscOptionsBoolGroup("-svd_conv_abs","Absolute error convergence test","SVDSetConvergenceTest",&flg);
    679:     if (flg) { SVDSetConvergenceTest(svd,SVD_CONV_ABS); }
    680:     PetscOptionsBoolGroupEnd("-svd_conv_user","User-defined convergence test","SVDSetConvergenceTest",&flg);
    681:     if (flg) { SVDSetConvergenceTest(svd,SVD_CONV_USER); }

    683:     PetscOptionsBoolGroupBegin("-svd_stop_basic","Stop iteration if all singular values converged or max_it reached","SVDSetStoppingTest",&flg);
    684:     if (flg) { SVDSetStoppingTest(svd,SVD_STOP_BASIC); }
    685:     PetscOptionsBoolGroupEnd("-svd_stop_user","User-defined stopping test","SVDSetStoppingTest",&flg);
    686:     if (flg) { SVDSetStoppingTest(svd,SVD_STOP_USER); }

    688:     i = svd->nsv;
    689:     PetscOptionsInt("-svd_nsv","Number of singular values to compute","SVDSetDimensions",svd->nsv,&i,&flg1);
    690:     j = svd->ncv;
    691:     PetscOptionsInt("-svd_ncv","Number of basis vectors","SVDSetDimensions",svd->ncv,&j,&flg2);
    692:     k = svd->mpd;
    693:     PetscOptionsInt("-svd_mpd","Maximum dimension of projected problem","SVDSetDimensions",svd->mpd,&k,&flg3);
    694:     if (flg1 || flg2 || flg3) { SVDSetDimensions(svd,i,j,k); }

    696:     PetscOptionsBoolGroupBegin("-svd_largest","Compute largest singular values","SVDSetWhichSingularTriplets",&flg);
    697:     if (flg) { SVDSetWhichSingularTriplets(svd,SVD_LARGEST); }
    698:     PetscOptionsBoolGroupEnd("-svd_smallest","Compute smallest singular values","SVDSetWhichSingularTriplets",&flg);
    699:     if (flg) { SVDSetWhichSingularTriplets(svd,SVD_SMALLEST); }

    701:     /* -----------------------------------------------------------------------*/
    702:     /*
    703:       Cancels all monitors hardwired into code before call to SVDSetFromOptions()
    704:     */
    705:     PetscOptionsBool("-svd_monitor_cancel","Remove any hardwired monitor routines","SVDMonitorCancel",PETSC_FALSE,&flg,&set);
    706:     if (set && flg) {
    707:       SVDMonitorCancel(svd);
    708:     }
    709:     /*
    710:       Text monitors
    711:     */
    712:     SVDMonitorSetFromOptions(svd,"-svd_monitor","Monitor first unconverged approximate singular value and error estimate","SVDMonitorFirst",SVDMonitorFirst,PETSC_FALSE);
    713:     SVDConvMonitorSetFromOptions(svd,"-svd_monitor_conv","Monitor approximate singular values and error estimates as they converge","SVDMonitorConverged",SVDMonitorConverged);
    714:     SVDMonitorSetFromOptions(svd,"-svd_monitor_all","Monitor approximate singular values and error estimates","SVDMonitorAll",SVDMonitorAll,PETSC_TRUE);
    715:     /*
    716:       Line graph monitors
    717:     */
    718:     PetscOptionsBool("-svd_monitor_lg","Monitor first unconverged approximate singular value and error estimate graphically","SVDMonitorSet",PETSC_FALSE,&flg,&set);
    719:     if (set && flg) {
    720:       SVDMonitorLGCreate(PetscObjectComm((PetscObject)svd),NULL,"Error estimates",PETSC_DECIDE,PETSC_DECIDE,300,300,&lg);
    721:       SVDMonitorSet(svd,SVDMonitorLG,lg,(PetscErrorCode (*)(void**))PetscDrawLGDestroy);
    722:     }
    723:     PetscOptionsBool("-svd_monitor_lg_all","Monitor error estimates graphically","SVDMonitorSet",PETSC_FALSE,&flg,&set);
    724:     if (set && flg) {
    725:       SVDMonitorLGCreate(PetscObjectComm((PetscObject)svd),NULL,"Error estimates",PETSC_DECIDE,PETSC_DECIDE,300,300,&lg);
    726:       SVDMonitorSet(svd,SVDMonitorLGAll,lg,(PetscErrorCode (*)(void**))PetscDrawLGDestroy);
    727:       SVDSetTrackAll(svd,PETSC_TRUE);
    728:     }

    730:     /* -----------------------------------------------------------------------*/
    731:     PetscOptionsName("-svd_view","Print detailed information on solver used","SVDView",NULL);
    732:     PetscOptionsName("-svd_view_vectors","View computed singular vectors","SVDVectorsView",NULL);
    733:     PetscOptionsName("-svd_view_values","View computed singular values","SVDValuesView",NULL);
    734:     PetscOptionsName("-svd_converged_reason","Print reason for convergence, and number of iterations","SVDConvergedReasonView",NULL);
    735:     PetscOptionsName("-svd_error_absolute","Print absolute errors of each singular triplet","SVDErrorView",NULL);
    736:     PetscOptionsName("-svd_error_relative","Print relative errors of each singular triplet","SVDErrorView",NULL);

    738:     if (svd->ops->setfromoptions) {
    739:       (*svd->ops->setfromoptions)(PetscOptionsObject,svd);
    740:     }
    741:     PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)svd);
    742:   PetscOptionsEnd();

    744:   if (!svd->V) { SVDGetBV(svd,&svd->V,NULL); }
    745:   BVSetFromOptions(svd->V);
    746:   if (!svd->U) { SVDGetBV(svd,NULL,&svd->U); }
    747:   BVSetFromOptions(svd->U);
    748:   if (!svd->ds) { SVDGetDS(svd,&svd->ds); }
    749:   DSSetFromOptions(svd->ds);
    750:   return(0);
    751: }

    753: /*@
    754:    SVDSetTrackAll - Specifies if the solver must compute the residual norm of all
    755:    approximate singular value or not.

    757:    Logically Collective on svd

    759:    Input Parameters:
    760: +  svd      - the singular value solver context
    761: -  trackall - whether to compute all residuals or not

    763:    Notes:
    764:    If the user sets trackall=PETSC_TRUE then the solver computes (or estimates)
    765:    the residual norm for each singular value approximation. Computing the residual is
    766:    usually an expensive operation and solvers commonly compute only the residual
    767:    associated to the first unconverged singular value.

    769:    The options '-svd_monitor_all' and '-svd_monitor_lg_all' automatically
    770:    activate this option.

    772:    Level: developer

    774: .seealso: SVDGetTrackAll()
    775: @*/
    776: PetscErrorCode SVDSetTrackAll(SVD svd,PetscBool trackall)
    777: {
    781:   svd->trackall = trackall;
    782:   return(0);
    783: }

    785: /*@
    786:    SVDGetTrackAll - Returns the flag indicating whether all residual norms must
    787:    be computed or not.

    789:    Not Collective

    791:    Input Parameter:
    792: .  svd - the singular value solver context

    794:    Output Parameter:
    795: .  trackall - the returned flag

    797:    Level: developer

    799: .seealso: SVDSetTrackAll()
    800: @*/
    801: PetscErrorCode SVDGetTrackAll(SVD svd,PetscBool *trackall)
    802: {
    806:   *trackall = svd->trackall;
    807:   return(0);
    808: }

    811: /*@C
    812:    SVDSetOptionsPrefix - Sets the prefix used for searching for all
    813:    SVD options in the database.

    815:    Logically Collective on svd

    817:    Input Parameters:
    818: +  svd - the singular value solver context
    819: -  prefix - the prefix string to prepend to all SVD option requests

    821:    Notes:
    822:    A hyphen (-) must NOT be given at the beginning of the prefix name.
    823:    The first character of all runtime options is AUTOMATICALLY the
    824:    hyphen.

    826:    For example, to distinguish between the runtime options for two
    827:    different SVD contexts, one could call
    828: .vb
    829:       SVDSetOptionsPrefix(svd1,"svd1_")
    830:       SVDSetOptionsPrefix(svd2,"svd2_")
    831: .ve

    833:    Level: advanced

    835: .seealso: SVDAppendOptionsPrefix(), SVDGetOptionsPrefix()
    836: @*/
    837: PetscErrorCode SVDSetOptionsPrefix(SVD svd,const char *prefix)
    838: {

    843:   if (!svd->V) { SVDGetBV(svd,&svd->V,&svd->U); }
    844:   BVSetOptionsPrefix(svd->V,prefix);
    845:   BVSetOptionsPrefix(svd->U,prefix);
    846:   if (!svd->ds) { SVDGetDS(svd,&svd->ds); }
    847:   DSSetOptionsPrefix(svd->ds,prefix);
    848:   PetscObjectSetOptionsPrefix((PetscObject)svd,prefix);
    849:   return(0);
    850: }

    852: /*@C
    853:    SVDAppendOptionsPrefix - Appends to the prefix used for searching for all
    854:    SVD options in the database.

    856:    Logically Collective on svd

    858:    Input Parameters:
    859: +  svd - the singular value solver context
    860: -  prefix - the prefix string to prepend to all SVD option requests

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

    866:    Level: advanced

    868: .seealso: SVDSetOptionsPrefix(), SVDGetOptionsPrefix()
    869: @*/
    870: PetscErrorCode SVDAppendOptionsPrefix(SVD svd,const char *prefix)
    871: {

    876:   if (!svd->V) { SVDGetBV(svd,&svd->V,&svd->U); }
    877:   BVAppendOptionsPrefix(svd->V,prefix);
    878:   BVAppendOptionsPrefix(svd->U,prefix);
    879:   if (!svd->ds) { SVDGetDS(svd,&svd->ds); }
    880:   DSAppendOptionsPrefix(svd->ds,prefix);
    881:   PetscObjectAppendOptionsPrefix((PetscObject)svd,prefix);
    882:   return(0);
    883: }

    885: /*@C
    886:    SVDGetOptionsPrefix - Gets the prefix used for searching for all
    887:    SVD options in the database.

    889:    Not Collective

    891:    Input Parameters:
    892: .  svd - the singular value solver context

    894:    Output Parameters:
    895: .  prefix - pointer to the prefix string used is returned

    897:    Note:
    898:    On the Fortran side, the user should pass in a string 'prefix' of
    899:    sufficient length to hold the prefix.

    901:    Level: advanced

    903: .seealso: SVDSetOptionsPrefix(), SVDAppendOptionsPrefix()
    904: @*/
    905: PetscErrorCode SVDGetOptionsPrefix(SVD svd,const char *prefix[])
    906: {

    912:   PetscObjectGetOptionsPrefix((PetscObject)svd,prefix);
    913:   return(0);
    914: }