Actual source code: matrix.c

  1: #define PETSCMAT_DLL

  3: /*
  4:    This is where the abstract matrix operations are defined
  5: */

 7:  #include private/matimpl.h
 8:  #include private/vecimpl.h

 10: /* Logging support */
 11: PetscCookie  MAT_COOKIE;
 12: PetscCookie  MAT_FDCOLORING_COOKIE;

 14: PetscLogEvent  MAT_Mult, MAT_Mults, MAT_MultConstrained, MAT_MultAdd, MAT_MultTranspose;
 15: PetscLogEvent  MAT_MultTransposeConstrained, MAT_MultTransposeAdd, MAT_Solve, MAT_Solves, MAT_SolveAdd, MAT_SolveTranspose, MAT_MatSolve;
 16: PetscLogEvent  MAT_SolveTransposeAdd, MAT_Relax, MAT_ForwardSolve, MAT_BackwardSolve, MAT_LUFactor, MAT_LUFactorSymbolic;
 17: PetscLogEvent  MAT_LUFactorNumeric, MAT_CholeskyFactor, MAT_CholeskyFactorSymbolic, MAT_CholeskyFactorNumeric, MAT_ILUFactor;
 18: PetscLogEvent  MAT_ILUFactorSymbolic, MAT_ICCFactorSymbolic, MAT_Copy, MAT_Convert, MAT_Scale, MAT_AssemblyBegin;
 19: PetscLogEvent  MAT_AssemblyEnd, MAT_SetValues, MAT_GetValues, MAT_GetRow, MAT_GetRowIJ, MAT_GetSubMatrices, MAT_GetColoring, MAT_GetOrdering, MAT_GetRedundantMatrix, MAT_GetSeqNonzeroStructure;
 20: PetscLogEvent  MAT_IncreaseOverlap, MAT_Partitioning, MAT_ZeroEntries, MAT_Load, MAT_View, MAT_AXPY, MAT_FDColoringCreate;
 21: PetscLogEvent  MAT_FDColoringApply,MAT_Transpose,MAT_FDColoringFunction;
 22: PetscLogEvent  MAT_MatMult, MAT_MatMultSymbolic, MAT_MatMultNumeric;
 23: PetscLogEvent  MAT_PtAP, MAT_PtAPSymbolic, MAT_PtAPNumeric;
 24: PetscLogEvent  MAT_MatMultTranspose, MAT_MatMultTransposeSymbolic, MAT_MatMultTransposeNumeric;
 25: PetscLogEvent  MAT_Getsymtranspose, MAT_Getsymtransreduced, MAT_Transpose_SeqAIJ, MAT_GetBrowsOfAcols;
 26: PetscLogEvent  MAT_GetBrowsOfAocols, MAT_Getlocalmat, MAT_Getlocalmatcondensed, MAT_Seqstompi, MAT_Seqstompinum, MAT_Seqstompisym;
 27: PetscLogEvent  MAT_Applypapt, MAT_Applypapt_numeric, MAT_Applypapt_symbolic, MAT_GetSequentialNonzeroStructure;

 29: /* nasty global values for MatSetValue() */
 30: PetscInt     MatSetValue_Row = 0;
 31: PetscInt     MatSetValue_Column = 0;
 32: PetscScalar  MatSetValue_Value = 0.0;

 36: /*@
 37:    MatGetDiagonalBlock - Returns the part of the matrix associated with the on-process coupling

 39:    Not Collective

 41:    Input Parameters:
 42: +  mat - the matrix
 43: -  reuse - indicates you are passing in the a matrix and want it reused

 45:    Output Parameters:
 46: +   iscopy - indicates a copy of the diagonal matrix was created and you should use MatDestroy() on it
 47: -   a - the diagonal part (which is a SEQUENTIAL matrix)

 49:    Notes: see the manual page for MatCreateMPIAIJ() for more information on the "diagonal part" of the matrix

 51:    Level: advanced

 53: @*/
 54: PetscErrorCode  MatGetDiagonalBlock(Mat A,PetscTruth *iscopy,MatReuse reuse,Mat *a)
 55: {
 56:   PetscErrorCode ierr,(*f)(Mat,PetscTruth*,MatReuse,Mat*);
 57:   PetscMPIInt    size;

 60:   MPI_Comm_size(((PetscObject)A)->comm,&size);
 61:   PetscObjectQueryFunction((PetscObject)A,"MatGetDiagonalBlock_C",(void (**)(void))&f);
 62:   if (f) {
 63:     (*f)(A,iscopy,reuse,a);
 64:   } else if (size == 1) {
 65:     *a = A;
 66:   } else {
 67:     SETERRQ(PETSC_ERR_SUP,"Cannot get diagonal part for this matrix");
 68:   }
 69:   return(0);
 70: }

 74: /*@
 75:    MatRealPart - Zeros out the imaginary part of the matrix

 77:    Collective on Mat

 79:    Input Parameters:
 80: .  mat - the matrix

 82:    Level: advanced


 85: .seealso: MatImaginaryPart()
 86: @*/
 87: PetscErrorCode  MatRealPart(Mat mat)
 88: {

 94:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
 95:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
 96:   if (!mat->ops->realpart) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
 97:   MatPreallocated(mat);
 98:   (*mat->ops->realpart)(mat);
 99:   return(0);
100: }


105: /*@
106:    MatImaginaryPart - Moves the imaginary part of the matrix to the real part and zeros the imaginary part

108:    Collective on Mat

110:    Input Parameters:
111: .  mat - the matrix

113:    Level: advanced


116: .seealso: MatRealPart()
117: @*/
118: PetscErrorCode  MatImaginaryPart(Mat mat)
119: {

125:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
126:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
127:   if (!mat->ops->imaginarypart) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
128:   MatPreallocated(mat);
129:   (*mat->ops->imaginarypart)(mat);
130:   return(0);
131: }

135: /*@
136:    MatMissingDiagonal - Determine if sparse matrix is missing a diagonal entry (or block entry for BAIJ matrices)

138:    Collective on Mat

140:    Input Parameter:
141: .  mat - the matrix

143:    Output Parameters:
144: +  missing - is any diagonal missing
145: -  dd - first diagonal entry that is missing (optional)

147:    Level: advanced


150: .seealso: MatRealPart()
151: @*/
152: PetscErrorCode  MatMissingDiagonal(Mat mat,PetscTruth *missing,PetscInt *dd)
153: {

159:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
160:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
161:   if (!mat->ops->missingdiagonal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
162:   (*mat->ops->missingdiagonal)(mat,missing,dd);
163:   return(0);
164: }

168: /*@C
169:    MatGetRow - Gets a row of a matrix.  You MUST call MatRestoreRow()
170:    for each row that you get to ensure that your application does
171:    not bleed memory.

173:    Not Collective

175:    Input Parameters:
176: +  mat - the matrix
177: -  row - the row to get

179:    Output Parameters:
180: +  ncols -  if not NULL, the number of nonzeros in the row
181: .  cols - if not NULL, the column numbers
182: -  vals - if not NULL, the values

184:    Notes:
185:    This routine is provided for people who need to have direct access
186:    to the structure of a matrix.  We hope that we provide enough
187:    high-level matrix routines that few users will need it. 

189:    MatGetRow() always returns 0-based column indices, regardless of
190:    whether the internal representation is 0-based (default) or 1-based.

192:    For better efficiency, set cols and/or vals to PETSC_NULL if you do
193:    not wish to extract these quantities.

195:    The user can only examine the values extracted with MatGetRow();
196:    the values cannot be altered.  To change the matrix entries, one
197:    must use MatSetValues().

199:    You can only have one call to MatGetRow() outstanding for a particular
200:    matrix at a time, per processor. MatGetRow() can only obtain rows
201:    associated with the given processor, it cannot get rows from the 
202:    other processors; for that we suggest using MatGetSubMatrices(), then
203:    MatGetRow() on the submatrix. The row indix passed to MatGetRows() 
204:    is in the global number of rows.

206:    Fortran Notes:
207:    The calling sequence from Fortran is 
208: .vb
209:    MatGetRow(matrix,row,ncols,cols,values,ierr)
210:          Mat     matrix (input)
211:          integer row    (input)
212:          integer ncols  (output)
213:          integer cols(maxcols) (output)
214:          double precision (or double complex) values(maxcols) output
215: .ve
216:    where maxcols >= maximum nonzeros in any row of the matrix.


219:    Caution:
220:    Do not try to change the contents of the output arrays (cols and vals).
221:    In some cases, this may corrupt the matrix.

223:    Level: advanced

225:    Concepts: matrices^row access

227: .seealso: MatRestoreRow(), MatSetValues(), MatGetValues(), MatGetSubMatrices(), MatGetDiagonal()
228: @*/
229: PetscErrorCode  MatGetRow(Mat mat,PetscInt row,PetscInt *ncols,const PetscInt *cols[],const PetscScalar *vals[])
230: {
232:   PetscInt       incols;

237:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
238:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
239:   if (!mat->ops->getrow) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
240:   MatPreallocated(mat);
241:   PetscLogEventBegin(MAT_GetRow,mat,0,0,0);
242:   (*mat->ops->getrow)(mat,row,&incols,(PetscInt **)cols,(PetscScalar **)vals);
243:   if (ncols) *ncols = incols;
244:   PetscLogEventEnd(MAT_GetRow,mat,0,0,0);
245:   return(0);
246: }

250: /*@
251:    MatConjugate - replaces the matrix values with their complex conjugates

253:    Collective on Mat

255:    Input Parameters:
256: .  mat - the matrix

258:    Level: advanced

260: .seealso:  VecConjugate()
261: @*/
262: PetscErrorCode  MatConjugate(Mat mat)
263: {

268:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
269:   if (!mat->ops->conjugate) SETERRQ(PETSC_ERR_SUP,"Not provided for this matrix format, send email to petsc-maint@mcs.anl.gov");
270:   (*mat->ops->conjugate)(mat);
271:   return(0);
272: }

276: /*@C  
277:    MatRestoreRow - Frees any temporary space allocated by MatGetRow().

279:    Not Collective

281:    Input Parameters:
282: +  mat - the matrix
283: .  row - the row to get
284: .  ncols, cols - the number of nonzeros and their columns
285: -  vals - if nonzero the column values

287:    Notes: 
288:    This routine should be called after you have finished examining the entries.

290:    Fortran Notes:
291:    The calling sequence from Fortran is 
292: .vb
293:    MatRestoreRow(matrix,row,ncols,cols,values,ierr)
294:       Mat     matrix (input)
295:       integer row    (input)
296:       integer ncols  (output)
297:       integer cols(maxcols) (output)
298:       double precision (or double complex) values(maxcols) output
299: .ve
300:    Where maxcols >= maximum nonzeros in any row of the matrix. 

302:    In Fortran MatRestoreRow() MUST be called after MatGetRow()
303:    before another call to MatGetRow() can be made.

305:    Level: advanced

307: .seealso:  MatGetRow()
308: @*/
309: PetscErrorCode  MatRestoreRow(Mat mat,PetscInt row,PetscInt *ncols,const PetscInt *cols[],const PetscScalar *vals[])
310: {

316:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
317:   if (!mat->ops->restorerow) return(0);
318:   (*mat->ops->restorerow)(mat,row,ncols,(PetscInt **)cols,(PetscScalar **)vals);
319:   return(0);
320: }

324: /*@
325:    MatGetRowUpperTriangular - Sets a flag to enable calls to MatGetRow() for matrix in MATSBAIJ format.  
326:    You should call MatRestoreRowUpperTriangular() after calling MatGetRow/MatRestoreRow() to disable the flag. 

328:    Not Collective

330:    Input Parameters:
331: +  mat - the matrix

333:    Notes:
334:    The flag is to ensure that users are aware of MatGetRow() only provides the upper trianglular part of the row for the matrices in MATSBAIJ format.

336:    Level: advanced

338:    Concepts: matrices^row access

340: .seealso: MatRestoreRowRowUpperTriangular()
341: @*/
342: PetscErrorCode  MatGetRowUpperTriangular(Mat mat)
343: {

349:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
350:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
351:   if (!mat->ops->getrowuppertriangular) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
352:   MatPreallocated(mat);
353:   (*mat->ops->getrowuppertriangular)(mat);
354:   return(0);
355: }

359: /*@
360:    MatRestoreRowUpperTriangular - Disable calls to MatGetRow() for matrix in MATSBAIJ format.  

362:    Not Collective

364:    Input Parameters:
365: +  mat - the matrix

367:    Notes: 
368:    This routine should be called after you have finished MatGetRow/MatRestoreRow().


371:    Level: advanced

373: .seealso:  MatGetRowUpperTriangular()
374: @*/
375: PetscErrorCode  MatRestoreRowUpperTriangular(Mat mat)
376: {

381:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
382:   if (!mat->ops->restorerowuppertriangular) return(0);
383:   (*mat->ops->restorerowuppertriangular)(mat);
384:   return(0);
385: }

389: /*@C
390:    MatSetOptionsPrefix - Sets the prefix used for searching for all 
391:    Mat options in the database.

393:    Collective on Mat

395:    Input Parameter:
396: +  A - the Mat context
397: -  prefix - the prefix to prepend to all option names

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

403:    Level: advanced

405: .keywords: Mat, set, options, prefix, database

407: .seealso: MatSetFromOptions()
408: @*/
409: PetscErrorCode  MatSetOptionsPrefix(Mat A,const char prefix[])
410: {

415:   PetscObjectSetOptionsPrefix((PetscObject)A,prefix);
416:   return(0);
417: }

421: /*@C
422:    MatAppendOptionsPrefix - Appends to the prefix used for searching for all 
423:    Mat options in the database.

425:    Collective on Mat

427:    Input Parameters:
428: +  A - the Mat context
429: -  prefix - the prefix to prepend to all option names

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

435:    Level: advanced

437: .keywords: Mat, append, options, prefix, database

439: .seealso: MatGetOptionsPrefix()
440: @*/
441: PetscErrorCode  MatAppendOptionsPrefix(Mat A,const char prefix[])
442: {
444: 
447:   PetscObjectAppendOptionsPrefix((PetscObject)A,prefix);
448:   return(0);
449: }

453: /*@C
454:    MatGetOptionsPrefix - Sets the prefix used for searching for all 
455:    Mat options in the database.

457:    Not Collective

459:    Input Parameter:
460: .  A - the Mat context

462:    Output Parameter:
463: .  prefix - pointer to the prefix string used

465:    Notes: On the fortran side, the user should pass in a string 'prefix' of
466:    sufficient length to hold the prefix.

468:    Level: advanced

470: .keywords: Mat, get, options, prefix, database

472: .seealso: MatAppendOptionsPrefix()
473: @*/
474: PetscErrorCode  MatGetOptionsPrefix(Mat A,const char *prefix[])
475: {

480:   PetscObjectGetOptionsPrefix((PetscObject)A,prefix);
481:   return(0);
482: }

486: /*@
487:    MatSetUp - Sets up the internal matrix data structures for the later use.

489:    Collective on Mat

491:    Input Parameters:
492: .  A - the Mat context

494:    Notes:
495:    For basic use of the Mat classes the user need not explicitly call
496:    MatSetUp(), since these actions will happen automatically.

498:    Level: advanced

500: .keywords: Mat, setup

502: .seealso: MatCreate(), MatDestroy()
503: @*/
504: PetscErrorCode  MatSetUp(Mat A)
505: {
506:   PetscMPIInt    size;

511:   if (!((PetscObject)A)->type_name) {
512:     MPI_Comm_size(((PetscObject)A)->comm, &size);
513:     if (size == 1) {
514:       MatSetType(A, MATSEQAIJ);
515:     } else {
516:       MatSetType(A, MATMPIAIJ);
517:     }
518:   }
519:   MatSetUpPreallocation(A);
520:   return(0);
521: }

525: /*@C
526:    MatView - Visualizes a matrix object.

528:    Collective on Mat

530:    Input Parameters:
531: +  mat - the matrix
532: -  viewer - visualization context

534:   Notes:
535:   The available visualization contexts include
536: +    PETSC_VIEWER_STDOUT_SELF - standard output (default)
537: .    PETSC_VIEWER_STDOUT_WORLD - synchronized standard
538:         output where only the first processor opens
539:         the file.  All other processors send their 
540:         data to the first processor to print. 
541: -     PETSC_VIEWER_DRAW_WORLD - graphical display of nonzero structure

543:    The user can open alternative visualization contexts with
544: +    PetscViewerASCIIOpen() - Outputs matrix to a specified file
545: .    PetscViewerBinaryOpen() - Outputs matrix in binary to a
546:          specified file; corresponding input uses MatLoad()
547: .    PetscViewerDrawOpen() - Outputs nonzero matrix structure to 
548:          an X window display
549: -    PetscViewerSocketOpen() - Outputs matrix to Socket viewer.
550:          Currently only the sequential dense and AIJ
551:          matrix types support the Socket viewer.

553:    The user can call PetscViewerSetFormat() to specify the output
554:    format of ASCII printed objects (when using PETSC_VIEWER_STDOUT_SELF,
555:    PETSC_VIEWER_STDOUT_WORLD and PetscViewerASCIIOpen).  Available formats include
556: +    PETSC_VIEWER_DEFAULT - default, prints matrix contents
557: .    PETSC_VIEWER_ASCII_MATLAB - prints matrix contents in Matlab format
558: .    PETSC_VIEWER_ASCII_DENSE - prints entire matrix including zeros
559: .    PETSC_VIEWER_ASCII_COMMON - prints matrix contents, using a sparse 
560:          format common among all matrix types
561: .    PETSC_VIEWER_ASCII_IMPL - prints matrix contents, using an implementation-specific 
562:          format (which is in many cases the same as the default)
563: .    PETSC_VIEWER_ASCII_INFO - prints basic information about the matrix
564:          size and structure (not the matrix entries)
565: .    PETSC_VIEWER_ASCII_INFO_DETAIL - prints more detailed information about
566:          the matrix structure

568:    Options Database Keys:
569: +  -mat_view_info - Prints info on matrix at conclusion of MatEndAssembly()
570: .  -mat_view_info_detailed - Prints more detailed info
571: .  -mat_view - Prints matrix in ASCII format
572: .  -mat_view_matlab - Prints matrix in Matlab format
573: .  -mat_view_draw - PetscDraws nonzero structure of matrix, using MatView() and PetscDrawOpenX().
574: .  -display <name> - Sets display name (default is host)
575: .  -draw_pause <sec> - Sets number of seconds to pause after display
576: .  -mat_view_socket - Sends matrix to socket, can be accessed from Matlab (see users manual)
577: .  -viewer_socket_machine <machine>
578: .  -viewer_socket_port <port>
579: .  -mat_view_binary - save matrix to file in binary format
580: -  -viewer_binary_filename <name>
581:    Level: beginner

583:    Notes: see the manual page for MatLoad() for the exact format of the binary file when the binary
584:       viewer is used.

586:       See bin/matlab/PetscBinaryRead.m for a Matlab code that can read in the binary file when the binary
587:       viewer is used.

589:    Concepts: matrices^viewing
590:    Concepts: matrices^plotting
591:    Concepts: matrices^printing

593: .seealso: PetscViewerSetFormat(), PetscViewerASCIIOpen(), PetscViewerDrawOpen(), 
594:           PetscViewerSocketOpen(), PetscViewerBinaryOpen(), MatLoad()
595: @*/
596: PetscErrorCode  MatView(Mat mat,PetscViewer viewer)
597: {
598:   PetscErrorCode    ierr;
599:   PetscInt          rows,cols;
600:   PetscTruth        iascii;
601:   const MatType     cstr;
602:   PetscViewerFormat format;

607:   if (!viewer) {
608:     PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);
609:   }
612:   if (!mat->assembled) SETERRQ(PETSC_ERR_ORDER,"Must call MatAssemblyBegin/End() before viewing matrix");
613:   MatPreallocated(mat);

615:   PetscLogEventBegin(MAT_View,mat,viewer,0,0);
616:   PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_ASCII,&iascii);
617:   if (iascii) {
618:     PetscViewerGetFormat(viewer,&format);
619:     if (format == PETSC_VIEWER_ASCII_INFO || format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
620:       if (((PetscObject)mat)->prefix) {
621:         PetscViewerASCIIPrintf(viewer,"Matrix Object:(%s)\n",((PetscObject)mat)->prefix);
622:       } else {
623:         PetscViewerASCIIPrintf(viewer,"Matrix Object:\n");
624:       }
625:       PetscViewerASCIIPushTab(viewer);
626:       MatGetType(mat,&cstr);
627:       MatGetSize(mat,&rows,&cols);
628:       PetscViewerASCIIPrintf(viewer,"type=%s, rows=%D, cols=%D\n",cstr,rows,cols);
629:       if (mat->factor) {
630:         const MatSolverPackage solver;
631:         MatFactorGetSolverPackage(mat,&solver);
632:         PetscViewerASCIIPrintf(viewer,"package used to perform factorization: %s\n",solver);
633:       }
634:       if (mat->ops->getinfo) {
635:         MatInfo info;
636:         MatGetInfo(mat,MAT_GLOBAL_SUM,&info);
637:         PetscViewerASCIIPrintf(viewer,"total: nonzeros=%D, allocated nonzeros=%D\n",(PetscInt)info.nz_used,(PetscInt)info.nz_allocated);
638:       }
639:     }
640:   }
641:   if (mat->ops->view) {
642:     PetscViewerASCIIPushTab(viewer);
643:     (*mat->ops->view)(mat,viewer);
644:     PetscViewerASCIIPopTab(viewer);
645:   } else if (!iascii) {
646:     SETERRQ1(PETSC_ERR_SUP,"Viewer type %s not supported",((PetscObject)viewer)->type_name);
647:   }
648:   if (iascii) {
649:     PetscViewerGetFormat(viewer,&format);
650:     if (format == PETSC_VIEWER_ASCII_INFO || format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
651:       PetscViewerASCIIPopTab(viewer);
652:     }
653:   }
654:   PetscLogEventEnd(MAT_View,mat,viewer,0,0);
655:   return(0);
656: }

660: /*@
661:    MatScaleSystem - Scale a vector solution and right hand side to 
662:    match the scaling of a scaled matrix.
663:   
664:    Collective on Mat

666:    Input Parameter:
667: +  mat - the matrix
668: .  b - right hand side vector (or PETSC_NULL)
669: -  x - solution vector (or PETSC_NULL)


672:    Notes: 
673:    For AIJ, and BAIJ matrix formats, the matrices are not 
674:    internally scaled, so this does nothing. For MPIROWBS it
675:    permutes and diagonally scales.

677:    The KSP methods automatically call this routine when required
678:    (via PCPreSolve()) so it is rarely used directly.

680:    Level: Developer            

682:    Concepts: matrices^scaling

684: .seealso: MatUseScaledForm(), MatUnScaleSystem()
685: @*/
686: PetscErrorCode  MatScaleSystem(Mat mat,Vec b,Vec x)
687: {

693:   MatPreallocated(mat);

697:   if (mat->ops->scalesystem) {
698:     (*mat->ops->scalesystem)(mat,b,x);
699:   }
700:   return(0);
701: }

705: /*@
706:    MatUnScaleSystem - Unscales a vector solution and right hand side to 
707:    match the original scaling of a scaled matrix.
708:   
709:    Collective on Mat

711:    Input Parameter:
712: +  mat - the matrix
713: .  b - right hand side vector (or PETSC_NULL)
714: -  x - solution vector (or PETSC_NULL)


717:    Notes: 
718:    For AIJ and BAIJ matrix formats, the matrices are not 
719:    internally scaled, so this does nothing. For MPIROWBS it
720:    permutes and diagonally scales.

722:    The KSP methods automatically call this routine when required
723:    (via PCPreSolve()) so it is rarely used directly.

725:    Level: Developer            

727: .seealso: MatUseScaledForm(), MatScaleSystem()
728: @*/
729: PetscErrorCode  MatUnScaleSystem(Mat mat,Vec b,Vec x)
730: {

736:   MatPreallocated(mat);
739:   if (mat->ops->unscalesystem) {
740:     (*mat->ops->unscalesystem)(mat,b,x);
741:   }
742:   return(0);
743: }

747: /*@
748:    MatUseScaledForm - For matrix storage formats that scale the 
749:    matrix (for example MPIRowBS matrices are diagonally scaled on
750:    assembly) indicates matrix operations (MatMult() etc) are 
751:    applied using the scaled matrix.
752:   
753:    Collective on Mat

755:    Input Parameter:
756: +  mat - the matrix
757: -  scaled - PETSC_TRUE for applying the scaled, PETSC_FALSE for 
758:             applying the original matrix

760:    Notes: 
761:    For scaled matrix formats, applying the original, unscaled matrix
762:    will be slightly more expensive

764:    Level: Developer            

766: .seealso: MatScaleSystem(), MatUnScaleSystem()
767: @*/
768: PetscErrorCode  MatUseScaledForm(Mat mat,PetscTruth scaled)
769: {

775:   MatPreallocated(mat);
776:   if (mat->ops->usescaledform) {
777:     (*mat->ops->usescaledform)(mat,scaled);
778:   }
779:   return(0);
780: }

784: /*@
785:    MatDestroy - Frees space taken by a matrix.
786:   
787:    Collective on Mat

789:    Input Parameter:
790: .  A - the matrix

792:    Level: beginner

794: @*/
795: PetscErrorCode  MatDestroy(Mat A)
796: {
800:   if (--((PetscObject)A)->refct > 0) return(0);
801:   MatPreallocated(A);
802:   /* if memory was published with AMS then destroy it */
803:   PetscObjectDepublish(A);
804:   if (A->ops->destroy) {
805:     (*A->ops->destroy)(A);
806:   }
807:   if (A->mapping) {
808:     ISLocalToGlobalMappingDestroy(A->mapping);
809:   }
810:   if (A->bmapping) {
811:     ISLocalToGlobalMappingDestroy(A->bmapping);
812:   }

814:   if (A->spptr){PetscFree(A->spptr);}
815:   PetscMapDestroy(A->rmap);
816:   PetscMapDestroy(A->cmap);
817:   PetscHeaderDestroy(A);
818:   return(0);
819: }

823: /*@
824:    MatValid - Checks whether a matrix object is valid.

826:    Collective on Mat

828:    Input Parameter:
829: .  m - the matrix to check 

831:    Output Parameter:
832:    flg - flag indicating matrix status, either
833:    PETSC_TRUE if matrix is valid, or PETSC_FALSE otherwise.

835:    Level: developer

837:    Concepts: matrices^validity
838: @*/
839: PetscErrorCode  MatValid(Mat m,PetscTruth *flg)
840: {
843:   if (!m)                                          *flg = PETSC_FALSE;
844:   else if (((PetscObject)m)->cookie != MAT_COOKIE) *flg = PETSC_FALSE;
845:   else                                             *flg = PETSC_TRUE;
846:   return(0);
847: }

851: /*@ 
852:    MatSetValues - Inserts or adds a block of values into a matrix.
853:    These values may be cached, so MatAssemblyBegin() and MatAssemblyEnd() 
854:    MUST be called after all calls to MatSetValues() have been completed.

856:    Not Collective

858:    Input Parameters:
859: +  mat - the matrix
860: .  v - a logically two-dimensional array of values
861: .  m, idxm - the number of rows and their global indices 
862: .  n, idxn - the number of columns and their global indices
863: -  addv - either ADD_VALUES or INSERT_VALUES, where
864:    ADD_VALUES adds values to any existing entries, and
865:    INSERT_VALUES replaces existing entries with new values

867:    Notes:
868:    By default the values, v, are row-oriented and unsorted.
869:    See MatSetOption() for other options.

871:    Calls to MatSetValues() with the INSERT_VALUES and ADD_VALUES 
872:    options cannot be mixed without intervening calls to the assembly
873:    routines.

875:    MatSetValues() uses 0-based row and column numbers in Fortran 
876:    as well as in C.

878:    Negative indices may be passed in idxm and idxn, these rows and columns are 
879:    simply ignored. This allows easily inserting element stiffness matrices
880:    with homogeneous Dirchlet boundary conditions that you don't want represented
881:    in the matrix.

883:    Efficiency Alert:
884:    The routine MatSetValuesBlocked() may offer much better efficiency
885:    for users of block sparse formats (MATSEQBAIJ and MATMPIBAIJ).

887:    Level: beginner

889:    Concepts: matrices^putting entries in

891: .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
892:           InsertMode, INSERT_VALUES, ADD_VALUES
893: @*/
894: PetscErrorCode  MatSetValues(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],const PetscScalar v[],InsertMode addv)
895: {

901:   if (!m || !n) return(0); /* no values to insert */
904:   MatPreallocated(mat);
905:   if (mat->insertmode == NOT_SET_VALUES) {
906:     mat->insertmode = addv;
907:   }
908: #if defined(PETSC_USE_DEBUG)
909:   else if (mat->insertmode != addv) {
910:     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
911:   }
912:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
913: #endif

915:   if (mat->assembled) {
916:     mat->was_assembled = PETSC_TRUE;
917:     mat->assembled     = PETSC_FALSE;
918:   }
919:   PetscLogEventBegin(MAT_SetValues,mat,0,0,0);
920:   if (!mat->ops->setvalues) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
921:   (*mat->ops->setvalues)(mat,m,idxm,n,idxn,v,addv);
922:   PetscLogEventEnd(MAT_SetValues,mat,0,0,0);
923:   return(0);
924: }


929: /*@ 
930:    MatSetValuesRowLocal - Inserts a row (block row for BAIJ matrices) of nonzero
931:         values into a matrix

933:    Not Collective

935:    Input Parameters:
936: +  mat - the matrix
937: .  row - the (block) row to set
938: -  v - a logically two-dimensional array of values

940:    Notes:
941:    By the values, v, are column-oriented (for the block version) and sorted

943:    All the nonzeros in the row must be provided

945:    The matrix must have previously had its column indices set

947:    The row must belong to this process

949:    Level: intermediate

951:    Concepts: matrices^putting entries in

953: .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
954:           InsertMode, INSERT_VALUES, ADD_VALUES, MatSetValues(), MatSetValuesRow(), MatSetLocalToGlobalMapping()
955: @*/
956: PetscErrorCode  MatSetValuesRowLocal(Mat mat,PetscInt row,const PetscScalar v[])
957: {

964:   MatSetValuesRow(mat, mat->mapping->indices[row],v);
965:   return(0);
966: }

970: /*@ 
971:    MatSetValuesRow - Inserts a row (block row for BAIJ matrices) of nonzero
972:         values into a matrix

974:    Not Collective

976:    Input Parameters:
977: +  mat - the matrix
978: .  row - the (block) row to set
979: -  v - a logically two-dimensional array of values

981:    Notes:
982:    By the values, v, are column-oriented (for the block version) and sorted

984:    All the nonzeros in the row must be provided

986:    The matrix must have previously had its column indices set

988:    The row must belong to this process

990:    Level: intermediate

992:    Concepts: matrices^putting entries in

994: .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal(),
995:           InsertMode, INSERT_VALUES, ADD_VALUES, MatSetValues()
996: @*/
997: PetscErrorCode  MatSetValuesRow(Mat mat,PetscInt row,const PetscScalar v[])
998: {

1005: #if defined(PETSC_USE_DEBUG)
1006:   if (mat->insertmode == ADD_VALUES) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add and insert values");
1007:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1008: #endif
1009:   mat->insertmode = INSERT_VALUES;

1011:   if (mat->assembled) {
1012:     mat->was_assembled = PETSC_TRUE;
1013:     mat->assembled     = PETSC_FALSE;
1014:   }
1015:   PetscLogEventBegin(MAT_SetValues,mat,0,0,0);
1016:   if (!mat->ops->setvaluesrow) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
1017:   (*mat->ops->setvaluesrow)(mat,row,v);
1018:   PetscLogEventEnd(MAT_SetValues,mat,0,0,0);
1019:   return(0);
1020: }

1024: /*@
1025:    MatSetValuesStencil - Inserts or adds a block of values into a matrix.
1026:      Using structured grid indexing

1028:    Not Collective

1030:    Input Parameters:
1031: +  mat - the matrix
1032: .  v - a logically two-dimensional array of values
1033: .  m - number of rows being entered
1034: .  idxm - grid coordinates (and component number when dof > 1) for matrix rows being entered
1035: .  n - number of columns being entered
1036: .  idxn - grid coordinates (and component number when dof > 1) for matrix columns being entered 
1037: -  addv - either ADD_VALUES or INSERT_VALUES, where
1038:    ADD_VALUES adds values to any existing entries, and
1039:    INSERT_VALUES replaces existing entries with new values

1041:    Notes:
1042:    By default the values, v, are row-oriented and unsorted.
1043:    See MatSetOption() for other options.

1045:    Calls to MatSetValuesStencil() with the INSERT_VALUES and ADD_VALUES 
1046:    options cannot be mixed without intervening calls to the assembly
1047:    routines.

1049:    The grid coordinates are across the entire grid, not just the local portion

1051:    MatSetValuesStencil() uses 0-based row and column numbers in Fortran 
1052:    as well as in C.

1054:    For setting/accessing vector values via array coordinates you can use the DAVecGetArray() routine

1056:    In order to use this routine you must either obtain the matrix with DAGetMatrix()
1057:    or call MatSetLocalToGlobalMapping() and MatSetStencil() first.

1059:    The columns and rows in the stencil passed in MUST be contained within the 
1060:    ghost region of the given process as set with DACreateXXX() or MatSetStencil(). For example,
1061:    if you create a DA with an overlap of one grid level and on a particular process its first
1062:    local nonghost x logical coordinate is 6 (so its first ghost x logical coordinate is 5) the
1063:    first i index you can use in your column and row indices in MatSetStencil() is 5.

1065:    In Fortran idxm and idxn should be declared as
1066: $     MatStencil idxm(4,m),idxn(4,n)
1067:    and the values inserted using
1068: $    idxm(MatStencil_i,1) = i
1069: $    idxm(MatStencil_j,1) = j
1070: $    idxm(MatStencil_k,1) = k
1071: $    idxm(MatStencil_c,1) = c
1072:    etc

1074:    For periodic boundary conditions use negative indices for values to the left (below 0; that are to be 
1075:    obtained by wrapping values from right edge). For values to the right of the last entry using that index plus one
1076:    etc to obtain values that obtained by wrapping the values from the left edge.

1078:    For indices that don't mean anything for your case (like the k index when working in 2d) or the c index when you have
1079:    a single value per point) you can skip filling those indices.

1081:    Inspired by the structured grid interface to the HYPRE package
1082:    (http://www.llnl.gov/CASC/hypre)

1084:    Efficiency Alert:
1085:    The routine MatSetValuesBlockedStencil() may offer much better efficiency
1086:    for users of block sparse formats (MATSEQBAIJ and MATMPIBAIJ).

1088:    Level: beginner

1090:    Concepts: matrices^putting entries in

1092: .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal()
1093:           MatSetValues(), MatSetValuesBlockedStencil(), MatSetStencil(), DAGetMatrix(), DAVecGetArray(), MatStencil
1094: @*/
1095: PetscErrorCode  MatSetValuesStencil(Mat mat,PetscInt m,const MatStencil idxm[],PetscInt n,const MatStencil idxn[],const PetscScalar v[],InsertMode addv)
1096: {
1098:   PetscInt       j,i,jdxm[128],jdxn[256],dim = mat->stencil.dim,*dims = mat->stencil.dims+1,tmp;
1099:   PetscInt       *starts = mat->stencil.starts,*dxm = (PetscInt*)idxm,*dxn = (PetscInt*)idxn,sdim = dim - (1 - (PetscInt)mat->stencil.noc);

1102:   if (!m || !n) return(0); /* no values to insert */

1109:   if (m > 128) SETERRQ1(PETSC_ERR_SUP,"Can only set 128 rows at a time; trying to set %D",m);
1110:   if (n > 256) SETERRQ1(PETSC_ERR_SUP,"Can only set 256 columns at a time; trying to set %D",n);

1112:   for (i=0; i<m; i++) {
1113:     for (j=0; j<3-sdim; j++) dxm++;
1114:     tmp = *dxm++ - starts[0];
1115:     for (j=0; j<dim-1; j++) {
1116:       if ((*dxm++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1117:       else                                       tmp = tmp*dims[j] + *(dxm-1) - starts[j+1];
1118:     }
1119:     if (mat->stencil.noc) dxm++;
1120:     jdxm[i] = tmp;
1121:   }
1122:   for (i=0; i<n; i++) {
1123:     for (j=0; j<3-sdim; j++) dxn++;
1124:     tmp = *dxn++ - starts[0];
1125:     for (j=0; j<dim-1; j++) {
1126:       if ((*dxn++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1127:       else                                       tmp = tmp*dims[j] + *(dxn-1) - starts[j+1];
1128:     }
1129:     if (mat->stencil.noc) dxn++;
1130:     jdxn[i] = tmp;
1131:   }
1132:   MatSetValuesLocal(mat,m,jdxm,n,jdxn,v,addv);
1133:   return(0);
1134: }

1138: /*@C 
1139:    MatSetValuesBlockedStencil - Inserts or adds a block of values into a matrix.
1140:      Using structured grid indexing

1142:    Not Collective

1144:    Input Parameters:
1145: +  mat - the matrix
1146: .  v - a logically two-dimensional array of values
1147: .  m - number of rows being entered
1148: .  idxm - grid coordinates for matrix rows being entered
1149: .  n - number of columns being entered
1150: .  idxn - grid coordinates for matrix columns being entered 
1151: -  addv - either ADD_VALUES or INSERT_VALUES, where
1152:    ADD_VALUES adds values to any existing entries, and
1153:    INSERT_VALUES replaces existing entries with new values

1155:    Notes:
1156:    By default the values, v, are row-oriented and unsorted.
1157:    See MatSetOption() for other options.

1159:    Calls to MatSetValuesBlockedStencil() with the INSERT_VALUES and ADD_VALUES 
1160:    options cannot be mixed without intervening calls to the assembly
1161:    routines.

1163:    The grid coordinates are across the entire grid, not just the local portion

1165:    MatSetValuesBlockedStencil() uses 0-based row and column numbers in Fortran 
1166:    as well as in C.

1168:    For setting/accessing vector values via array coordinates you can use the DAVecGetArray() routine

1170:    In order to use this routine you must either obtain the matrix with DAGetMatrix()
1171:    or call MatSetLocalToGlobalMapping() and MatSetStencil() first.

1173:    The columns and rows in the stencil passed in MUST be contained within the 
1174:    ghost region of the given process as set with DACreateXXX() or MatSetStencil(). For example,
1175:    if you create a DA with an overlap of one grid level and on a particular process its first
1176:    local nonghost x logical coordinate is 6 (so its first ghost x logical coordinate is 5) the
1177:    first i index you can use in your column and row indices in MatSetStencil() is 5.

1179:    In Fortran idxm and idxn should be declared as
1180: $     MatStencil idxm(4,m),idxn(4,n)
1181:    and the values inserted using
1182: $    idxm(MatStencil_i,1) = i
1183: $    idxm(MatStencil_j,1) = j
1184: $    idxm(MatStencil_k,1) = k
1185:    etc

1187:    Negative indices may be passed in idxm and idxn, these rows and columns are 
1188:    simply ignored. This allows easily inserting element stiffness matrices
1189:    with homogeneous Dirchlet boundary conditions that you don't want represented
1190:    in the matrix.

1192:    Inspired by the structured grid interface to the HYPRE package
1193:    (http://www.llnl.gov/CASC/hypre)

1195:    Level: beginner

1197:    Concepts: matrices^putting entries in

1199: .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal()
1200:           MatSetValues(), MatSetValuesStencil(), MatSetStencil(), DAGetMatrix(), DAVecGetArray(), MatStencil
1201: @*/
1202: PetscErrorCode  MatSetValuesBlockedStencil(Mat mat,PetscInt m,const MatStencil idxm[],PetscInt n,const MatStencil idxn[],const PetscScalar v[],InsertMode addv)
1203: {
1205:   PetscInt       j,i,jdxm[128],jdxn[256],dim = mat->stencil.dim,*dims = mat->stencil.dims+1,tmp;
1206:   PetscInt       *starts = mat->stencil.starts,*dxm = (PetscInt*)idxm,*dxn = (PetscInt*)idxn,sdim = dim - (1 - (PetscInt)mat->stencil.noc);

1209:   if (!m || !n) return(0); /* no values to insert */

1216:   if (m > 128) SETERRQ1(PETSC_ERR_SUP,"Can only set 128 rows at a time; trying to set %D",m);
1217:   if (n > 128) SETERRQ1(PETSC_ERR_SUP,"Can only set 256 columns at a time; trying to set %D",n);

1219:   for (i=0; i<m; i++) {
1220:     for (j=0; j<3-sdim; j++) dxm++;
1221:     tmp = *dxm++ - starts[0];
1222:     for (j=0; j<sdim-1; j++) {
1223:       if ((*dxm++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1224:       else                                      tmp = tmp*dims[j] + *(dxm-1) - starts[j+1];
1225:     }
1226:     dxm++;
1227:     jdxm[i] = tmp;
1228:   }
1229:   for (i=0; i<n; i++) {
1230:     for (j=0; j<3-sdim; j++) dxn++;
1231:     tmp = *dxn++ - starts[0];
1232:     for (j=0; j<sdim-1; j++) {
1233:       if ((*dxn++ - starts[j+1]) < 0 || tmp < 0) tmp = PETSC_MIN_INT;
1234:       else                                       tmp = tmp*dims[j] + *(dxn-1) - starts[j+1];
1235:     }
1236:     dxn++;
1237:     jdxn[i] = tmp;
1238:   }
1239:   MatSetValuesBlockedLocal(mat,m,jdxm,n,jdxn,v,addv);
1240:   return(0);
1241: }

1245: /*@ 
1246:    MatSetStencil - Sets the grid information for setting values into a matrix via
1247:         MatSetValuesStencil()

1249:    Not Collective

1251:    Input Parameters:
1252: +  mat - the matrix
1253: .  dim - dimension of the grid 1, 2, or 3
1254: .  dims - number of grid points in x, y, and z direction, including ghost points on your processor
1255: .  starts - starting point of ghost nodes on your processor in x, y, and z direction 
1256: -  dof - number of degrees of freedom per node


1259:    Inspired by the structured grid interface to the HYPRE package
1260:    (www.llnl.gov/CASC/hyper)

1262:    For matrices generated with DAGetMatrix() this routine is automatically called and so not needed by the
1263:    user.
1264:    
1265:    Level: beginner

1267:    Concepts: matrices^putting entries in

1269: .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesBlocked(), MatSetValuesLocal()
1270:           MatSetValues(), MatSetValuesBlockedStencil(), MatSetValuesStencil()
1271: @*/
1272: PetscErrorCode  MatSetStencil(Mat mat,PetscInt dim,const PetscInt dims[],const PetscInt starts[],PetscInt dof)
1273: {
1274:   PetscInt i;


1281:   mat->stencil.dim = dim + (dof > 1);
1282:   for (i=0; i<dim; i++) {
1283:     mat->stencil.dims[i]   = dims[dim-i-1];      /* copy the values in backwards */
1284:     mat->stencil.starts[i] = starts[dim-i-1];
1285:   }
1286:   mat->stencil.dims[dim]   = dof;
1287:   mat->stencil.starts[dim] = 0;
1288:   mat->stencil.noc         = (PetscTruth)(dof == 1);
1289:   return(0);
1290: }

1294: /*@ 
1295:    MatSetValuesBlocked - Inserts or adds a block of values into a matrix.

1297:    Not Collective

1299:    Input Parameters:
1300: +  mat - the matrix
1301: .  v - a logically two-dimensional array of values
1302: .  m, idxm - the number of block rows and their global block indices 
1303: .  n, idxn - the number of block columns and their global block indices
1304: -  addv - either ADD_VALUES or INSERT_VALUES, where
1305:    ADD_VALUES adds values to any existing entries, and
1306:    INSERT_VALUES replaces existing entries with new values

1308:    Notes:
1309:    The m and n count the NUMBER of blocks in the row direction and column direction,
1310:    NOT the total number of rows/columns; for example, if the block size is 2 and 
1311:    you are passing in values for rows 2,3,4,5  then m would be 2 (not 4).
1312:    The values in idxm would be 1 2; that is the first index for each block divided by 
1313:    the block size.

1315:    By default the values, v, are row-oriented and unsorted. So the layout of 
1316:    v is the same as for MatSetValues(). See MatSetOption() for other options.

1318:    Calls to MatSetValuesBlocked() with the INSERT_VALUES and ADD_VALUES 
1319:    options cannot be mixed without intervening calls to the assembly
1320:    routines.

1322:    MatSetValuesBlocked() uses 0-based row and column numbers in Fortran 
1323:    as well as in C.

1325:    Negative indices may be passed in idxm and idxn, these rows and columns are 
1326:    simply ignored. This allows easily inserting element stiffness matrices
1327:    with homogeneous Dirchlet boundary conditions that you don't want represented
1328:    in the matrix.

1330:    Each time an entry is set within a sparse matrix via MatSetValues(),
1331:    internal searching must be done to determine where to place the the
1332:    data in the matrix storage space.  By instead inserting blocks of 
1333:    entries via MatSetValuesBlocked(), the overhead of matrix assembly is
1334:    reduced.

1336:    Example:
1337: $   Suppose m=n=2 and block size(bs) = 2 The array is 
1338: $
1339: $   1  2  | 3  4
1340: $   5  6  | 7  8
1341: $   - - - | - - -
1342: $   9  10 | 11 12
1343: $   13 14 | 15 16
1344: $
1345: $   v[] should be passed in like
1346: $   v[] = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]
1347: $
1348: $  If you are not using row oriented storage of v (that is you called MatSetOption(mat,MAT_ROW_ORIENTED,PETSC_FALSE)) then
1349: $   v[] = [1,5,9,13,2,6,10,14,3,7,11,15,4,8,12,16]

1351:    Level: intermediate

1353:    Concepts: matrices^putting entries in blocked

1355: .seealso: MatSetOption(), MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetValuesBlockedLocal()
1356: @*/
1357: PetscErrorCode  MatSetValuesBlocked(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],const PetscScalar v[],InsertMode addv)
1358: {

1364:   if (!m || !n) return(0); /* no values to insert */
1368:   MatPreallocated(mat);
1369:   if (mat->insertmode == NOT_SET_VALUES) {
1370:     mat->insertmode = addv;
1371:   }
1372: #if defined(PETSC_USE_DEBUG) 
1373:   else if (mat->insertmode != addv) {
1374:     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
1375:   }
1376:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1377: #endif

1379:   if (mat->assembled) {
1380:     mat->was_assembled = PETSC_TRUE;
1381:     mat->assembled     = PETSC_FALSE;
1382:   }
1383:   PetscLogEventBegin(MAT_SetValues,mat,0,0,0);
1384:   if (mat->ops->setvaluesblocked) {
1385:     (*mat->ops->setvaluesblocked)(mat,m,idxm,n,idxn,v,addv);
1386:   } else {
1387:     PetscInt buf[4096],*ibufm=0,*ibufn=0;
1388:     PetscInt i,j,*iidxm,*iidxn,bs=mat->rmap->bs;
1389:     if ((m+n)*bs <= 4096) {
1390:       iidxm = buf; iidxn = buf + m*bs;
1391:     } else {
1392:       PetscMalloc2(m*bs,PetscInt,&ibufm,n*bs,PetscInt,&ibufn);
1393:       iidxm = ibufm; iidxn = ibufn;
1394:     }
1395:     for (i=0; i<m; i++) {
1396:       for (j=0; j<bs; j++) {
1397:         iidxm[i*bs+j] = bs*idxm[i] + j;
1398:       }
1399:     }
1400:     for (i=0; i<n; i++) {
1401:       for (j=0; j<bs; j++) {
1402:         iidxn[i*bs+j] = bs*idxn[i] + j;
1403:       }
1404:     }
1405:     MatSetValues(mat,bs*m,iidxm,bs*n,iidxn,v,addv);
1406:     PetscFree2(ibufm,ibufn);
1407:   }
1408:   PetscLogEventEnd(MAT_SetValues,mat,0,0,0);
1409:   return(0);
1410: }

1414: /*@ 
1415:    MatGetValues - Gets a block of values from a matrix.

1417:    Not Collective; currently only returns a local block

1419:    Input Parameters:
1420: +  mat - the matrix
1421: .  v - a logically two-dimensional array for storing the values
1422: .  m, idxm - the number of rows and their global indices 
1423: -  n, idxn - the number of columns and their global indices

1425:    Notes:
1426:    The user must allocate space (m*n PetscScalars) for the values, v.
1427:    The values, v, are then returned in a row-oriented format, 
1428:    analogous to that used by default in MatSetValues().

1430:    MatGetValues() uses 0-based row and column numbers in
1431:    Fortran as well as in C.

1433:    MatGetValues() requires that the matrix has been assembled
1434:    with MatAssemblyBegin()/MatAssemblyEnd().  Thus, calls to
1435:    MatSetValues() and MatGetValues() CANNOT be made in succession
1436:    without intermediate matrix assembly.

1438:    Negative row or column indices will be ignored and those locations in v[] will be 
1439:    left unchanged.

1441:    Level: advanced

1443:    Concepts: matrices^accessing values

1445: .seealso: MatGetRow(), MatGetSubMatrices(), MatSetValues()
1446: @*/
1447: PetscErrorCode  MatGetValues(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],PetscScalar v[])
1448: {

1457:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1458:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1459:   if (!mat->ops->getvalues) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
1460:   MatPreallocated(mat);

1462:   PetscLogEventBegin(MAT_GetValues,mat,0,0,0);
1463:   (*mat->ops->getvalues)(mat,m,idxm,n,idxn,v);
1464:   PetscLogEventEnd(MAT_GetValues,mat,0,0,0);
1465:   return(0);
1466: }

1470: /*@
1471:    MatSetLocalToGlobalMapping - Sets a local-to-global numbering for use by
1472:    the routine MatSetValuesLocal() to allow users to insert matrix entries
1473:    using a local (per-processor) numbering.

1475:    Not Collective

1477:    Input Parameters:
1478: +  x - the matrix
1479: -  mapping - mapping created with ISLocalToGlobalMappingCreate() 
1480:              or ISLocalToGlobalMappingCreateIS()

1482:    Level: intermediate

1484:    Concepts: matrices^local to global mapping
1485:    Concepts: local to global mapping^for matrices

1487: .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetValuesLocal()
1488: @*/
1489: PetscErrorCode  MatSetLocalToGlobalMapping(Mat x,ISLocalToGlobalMapping mapping)
1490: {
1496:   if (x->mapping) {
1497:     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Mapping already set for matrix");
1498:   }
1499:   MatPreallocated(x);

1501:   if (x->ops->setlocaltoglobalmapping) {
1502:     (*x->ops->setlocaltoglobalmapping)(x,mapping);
1503:   } else {
1504:     PetscObjectReference((PetscObject)mapping);
1505:     if (x->mapping) { ISLocalToGlobalMappingDestroy(x->mapping); }
1506:     x->mapping = mapping;
1507:   }
1508:   return(0);
1509: }

1513: /*@
1514:    MatSetLocalToGlobalMappingBlock - Sets a local-to-global numbering for use
1515:    by the routine MatSetValuesBlockedLocal() to allow users to insert matrix
1516:    entries using a local (per-processor) numbering.

1518:    Not Collective

1520:    Input Parameters:
1521: +  x - the matrix
1522: -  mapping - mapping created with ISLocalToGlobalMappingCreate() or
1523:              ISLocalToGlobalMappingCreateIS()

1525:    Level: intermediate

1527:    Concepts: matrices^local to global mapping blocked
1528:    Concepts: local to global mapping^for matrices, blocked

1530: .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetValuesBlockedLocal(),
1531:            MatSetValuesBlocked(), MatSetValuesLocal()
1532: @*/
1533: PetscErrorCode  MatSetLocalToGlobalMappingBlock(Mat x,ISLocalToGlobalMapping mapping)
1534: {
1540:   if (x->bmapping) {
1541:     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Mapping already set for matrix");
1542:   }
1543:   PetscObjectReference((PetscObject)mapping);
1544:   if (x->bmapping) { ISLocalToGlobalMappingDestroy(x->mapping); }
1545:   x->bmapping = mapping;
1546:   return(0);
1547: }

1551: /*@
1552:    MatSetValuesLocal - Inserts or adds values into certain locations of a matrix,
1553:    using a local ordering of the nodes. 

1555:    Not Collective

1557:    Input Parameters:
1558: +  x - the matrix
1559: .  nrow, irow - number of rows and their local indices
1560: .  ncol, icol - number of columns and their local indices
1561: .  y -  a logically two-dimensional array of values
1562: -  addv - either INSERT_VALUES or ADD_VALUES, where
1563:    ADD_VALUES adds values to any existing entries, and
1564:    INSERT_VALUES replaces existing entries with new values

1566:    Notes:
1567:    Before calling MatSetValuesLocal(), the user must first set the
1568:    local-to-global mapping by calling MatSetLocalToGlobalMapping().

1570:    Calls to MatSetValuesLocal() with the INSERT_VALUES and ADD_VALUES 
1571:    options cannot be mixed without intervening calls to the assembly
1572:    routines.

1574:    These values may be cached, so MatAssemblyBegin() and MatAssemblyEnd() 
1575:    MUST be called after all calls to MatSetValuesLocal() have been completed.

1577:    Level: intermediate

1579:    Concepts: matrices^putting entries in with local numbering

1581: .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValues(), MatSetLocalToGlobalMapping(),
1582:            MatSetValueLocal()
1583: @*/
1584: PetscErrorCode  MatSetValuesLocal(Mat mat,PetscInt nrow,const PetscInt irow[],PetscInt ncol,const PetscInt icol[],const PetscScalar y[],InsertMode addv)
1585: {
1587:   PetscInt       irowm[2048],icolm[2048];

1592:   if (!nrow || !ncol) return(0); /* no values to insert */
1596:   MatPreallocated(mat);
1597:   if (mat->insertmode == NOT_SET_VALUES) {
1598:     mat->insertmode = addv;
1599:   }
1600: #if defined(PETSC_USE_DEBUG) 
1601:   else if (mat->insertmode != addv) {
1602:     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
1603:   }
1604:   if (!mat->ops->setvalueslocal && (nrow > 2048 || ncol > 2048)) {
1605:     SETERRQ2(PETSC_ERR_SUP,"Number column/row indices must be <= 2048: are %D %D",nrow,ncol);
1606:   }
1607:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1608: #endif

1610:   if (mat->assembled) {
1611:     mat->was_assembled = PETSC_TRUE;
1612:     mat->assembled     = PETSC_FALSE;
1613:   }
1614:   PetscLogEventBegin(MAT_SetValues,mat,0,0,0);
1615:   if (!mat->ops->setvalueslocal) {
1616:     ISLocalToGlobalMappingApply(mat->mapping,nrow,irow,irowm);
1617:     ISLocalToGlobalMappingApply(mat->mapping,ncol,icol,icolm);
1618:     (*mat->ops->setvalues)(mat,nrow,irowm,ncol,icolm,y,addv);
1619:   } else {
1620:     (*mat->ops->setvalueslocal)(mat,nrow,irow,ncol,icol,y,addv);
1621:   }
1622:   mat->same_nonzero = PETSC_FALSE;
1623:   PetscLogEventEnd(MAT_SetValues,mat,0,0,0);
1624:   return(0);
1625: }

1629: /*@
1630:    MatSetValuesBlockedLocal - Inserts or adds values into certain locations of a matrix,
1631:    using a local ordering of the nodes a block at a time. 

1633:    Not Collective

1635:    Input Parameters:
1636: +  x - the matrix
1637: .  nrow, irow - number of rows and their local indices
1638: .  ncol, icol - number of columns and their local indices
1639: .  y -  a logically two-dimensional array of values
1640: -  addv - either INSERT_VALUES or ADD_VALUES, where
1641:    ADD_VALUES adds values to any existing entries, and
1642:    INSERT_VALUES replaces existing entries with new values

1644:    Notes:
1645:    Before calling MatSetValuesBlockedLocal(), the user must first set the
1646:    local-to-global mapping by calling MatSetLocalToGlobalMappingBlock(),
1647:    where the mapping MUST be set for matrix blocks, not for matrix elements.

1649:    Calls to MatSetValuesBlockedLocal() with the INSERT_VALUES and ADD_VALUES 
1650:    options cannot be mixed without intervening calls to the assembly
1651:    routines.

1653:    These values may be cached, so MatAssemblyBegin() and MatAssemblyEnd() 
1654:    MUST be called after all calls to MatSetValuesBlockedLocal() have been completed.

1656:    Level: intermediate

1658:    Concepts: matrices^putting blocked values in with local numbering

1660: .seealso:  MatAssemblyBegin(), MatAssemblyEnd(), MatSetValuesLocal(), MatSetLocalToGlobalMappingBlock(), MatSetValuesBlocked()
1661: @*/
1662: PetscErrorCode  MatSetValuesBlockedLocal(Mat mat,PetscInt nrow,const PetscInt irow[],PetscInt ncol,const PetscInt icol[],const PetscScalar y[],InsertMode addv)
1663: {
1665:   PetscInt       irowm[2048],icolm[2048];

1670:   if (!nrow || !ncol) return(0); /* no values to insert */
1674:   MatPreallocated(mat);
1675:   if (mat->insertmode == NOT_SET_VALUES) {
1676:     mat->insertmode = addv;
1677:   }
1678: #if defined(PETSC_USE_DEBUG) 
1679:   else if (mat->insertmode != addv) {
1680:     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
1681:   }
1682:   if (!mat->bmapping) {
1683:     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Local to global never set with MatSetLocalToGlobalMappingBlock()");
1684:   }
1685:   if (nrow > 2048 || ncol > 2048) {
1686:     SETERRQ2(PETSC_ERR_SUP,"Number column/row indices must be <= 2048: are %D %D",nrow,ncol);
1687:   }
1688:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1689: #endif

1691:   if (mat->assembled) {
1692:     mat->was_assembled = PETSC_TRUE;
1693:     mat->assembled     = PETSC_FALSE;
1694:   }
1695:   PetscLogEventBegin(MAT_SetValues,mat,0,0,0);
1696:   ISLocalToGlobalMappingApply(mat->bmapping,nrow,irow,irowm);
1697:   ISLocalToGlobalMappingApply(mat->bmapping,ncol,icol,icolm);
1698:   if (mat->ops->setvaluesblocked) {
1699:   (*mat->ops->setvaluesblocked)(mat,nrow,irowm,ncol,icolm,y,addv);
1700:   } else {
1701:     PetscInt buf[4096],*ibufm=0,*ibufn=0;
1702:     PetscInt i,j,*iirowm,*iicolm,bs=mat->rmap->bs;
1703:     if ((nrow+ncol)*bs <= 4096) {
1704:       iirowm = buf; iicolm = buf + nrow*bs;
1705:     } else {
1706:       PetscMalloc2(nrow*bs,PetscInt,&ibufm,ncol*bs,PetscInt,&ibufn);
1707:       iirowm = ibufm; iicolm = ibufn;
1708:     }
1709:     for (i=0; i<nrow; i++) {
1710:       for (j=0; j<bs; j++) {
1711:         iirowm[i*bs+j] = bs*irowm[i] + j;
1712:       }
1713:     }
1714:     for (i=0; i<ncol; i++) {
1715:       for (j=0; j<bs; j++) {
1716:         iicolm[i*bs+j] = bs*icolm[i] + j;
1717:       }
1718:     }
1719:     MatSetValues(mat,bs*nrow,iirowm,bs*ncol,iicolm,y,addv);
1720:     PetscFree2(ibufm,ibufn);
1721:   }
1722:   PetscLogEventEnd(MAT_SetValues,mat,0,0,0);
1723:   return(0);
1724: }

1726: /* --------------------------------------------------------*/
1729: /*@
1730:    MatMult - Computes the matrix-vector product, y = Ax.

1732:    Collective on Mat and Vec

1734:    Input Parameters:
1735: +  mat - the matrix
1736: -  x   - the vector to be multiplied

1738:    Output Parameters:
1739: .  y - the result

1741:    Notes:
1742:    The vectors x and y cannot be the same.  I.e., one cannot
1743:    call MatMult(A,y,y).

1745:    Level: beginner

1747:    Concepts: matrix-vector product

1749: .seealso: MatMultTranspose(), MatMultAdd(), MatMultTransposeAdd()
1750: @*/
1751: PetscErrorCode  MatMult(Mat mat,Vec x,Vec y)
1752: {


1761:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1762:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1763:   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1764: #ifndef PETSC_HAVE_CONSTRAINTS
1765:   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
1766:   if (mat->rmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->rmap->N,y->map->N);
1767:   if (mat->rmap->n != y->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: local dim %D %D",mat->rmap->n,y->map->n);
1768: #endif
1769:   MatPreallocated(mat);

1771:   if (mat->nullsp) {
1772:     MatNullSpaceRemove(mat->nullsp,x,&x);
1773:   }

1775:   if (!mat->ops->mult) SETERRQ(PETSC_ERR_SUP,"This matrix type does not have a multiply defined");
1776:   PetscLogEventBegin(MAT_Mult,mat,x,y,0);
1777:   (*mat->ops->mult)(mat,x,y);
1778:   PetscLogEventEnd(MAT_Mult,mat,x,y,0);

1780:   if (mat->nullsp) {
1781:     MatNullSpaceRemove(mat->nullsp,y,PETSC_NULL);
1782:   }
1783:   PetscObjectStateIncrease((PetscObject)y);
1784:   return(0);
1785: }

1789: /*@
1790:    MatMultTranspose - Computes matrix transpose times a vector.

1792:    Collective on Mat and Vec

1794:    Input Parameters:
1795: +  mat - the matrix
1796: -  x   - the vector to be multilplied

1798:    Output Parameters:
1799: .  y - the result

1801:    Notes:
1802:    The vectors x and y cannot be the same.  I.e., one cannot
1803:    call MatMultTranspose(A,y,y).

1805:    Level: beginner

1807:    Concepts: matrix vector product^transpose

1809: .seealso: MatMult(), MatMultAdd(), MatMultTransposeAdd()
1810: @*/
1811: PetscErrorCode  MatMultTranspose(Mat mat,Vec x,Vec y)
1812: {


1821:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1822:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1823:   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1824: #ifndef PETSC_HAVE_CONSTRAINTS
1825:   if (mat->rmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->rmap->N,x->map->N);
1826:   if (mat->cmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->cmap->N,y->map->N);
1827: #endif
1828:   MatPreallocated(mat);

1830:   if (!mat->ops->multtranspose) SETERRQ(PETSC_ERR_SUP,"This matrix type does not have a multiply tranpose defined");
1831:   PetscLogEventBegin(MAT_MultTranspose,mat,x,y,0);
1832:   (*mat->ops->multtranspose)(mat,x,y);
1833:   PetscLogEventEnd(MAT_MultTranspose,mat,x,y,0);
1834:   PetscObjectStateIncrease((PetscObject)y);
1835:   return(0);
1836: }

1840: /*@
1841:     MatMultAdd -  Computes v3 = v2 + A * v1.

1843:     Collective on Mat and Vec

1845:     Input Parameters:
1846: +   mat - the matrix
1847: -   v1, v2 - the vectors

1849:     Output Parameters:
1850: .   v3 - the result

1852:     Notes:
1853:     The vectors v1 and v3 cannot be the same.  I.e., one cannot
1854:     call MatMultAdd(A,v1,v2,v1).

1856:     Level: beginner

1858:     Concepts: matrix vector product^addition

1860: .seealso: MatMultTranspose(), MatMult(), MatMultTransposeAdd()
1861: @*/
1862: PetscErrorCode  MatMultAdd(Mat mat,Vec v1,Vec v2,Vec v3)
1863: {


1873:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1874:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1875:   if (mat->cmap->N != v1->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v1: global dim %D %D",mat->cmap->N,v1->map->N);
1876:   if (mat->rmap->N != v2->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v2: global dim %D %D",mat->rmap->N,v2->map->N);
1877:   if (mat->rmap->N != v3->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v3: global dim %D %D",mat->rmap->N,v3->map->N);
1878:   if (mat->rmap->n != v3->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v3: local dim %D %D",mat->rmap->n,v3->map->n);
1879:   if (mat->rmap->n != v2->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v2: local dim %D %D",mat->rmap->n,v2->map->n);
1880:   if (v1 == v3) SETERRQ(PETSC_ERR_ARG_IDN,"v1 and v3 must be different vectors");
1881:   MatPreallocated(mat);

1883:   PetscLogEventBegin(MAT_MultAdd,mat,v1,v2,v3);
1884:   (*mat->ops->multadd)(mat,v1,v2,v3);
1885:   PetscLogEventEnd(MAT_MultAdd,mat,v1,v2,v3);
1886:   PetscObjectStateIncrease((PetscObject)v3);
1887:   return(0);
1888: }

1892: /*@
1893:    MatMultTransposeAdd - Computes v3 = v2 + A' * v1.

1895:    Collective on Mat and Vec

1897:    Input Parameters:
1898: +  mat - the matrix
1899: -  v1, v2 - the vectors

1901:    Output Parameters:
1902: .  v3 - the result

1904:    Notes:
1905:    The vectors v1 and v3 cannot be the same.  I.e., one cannot
1906:    call MatMultTransposeAdd(A,v1,v2,v1).

1908:    Level: beginner

1910:    Concepts: matrix vector product^transpose and addition

1912: .seealso: MatMultTranspose(), MatMultAdd(), MatMult()
1913: @*/
1914: PetscErrorCode  MatMultTransposeAdd(Mat mat,Vec v1,Vec v2,Vec v3)
1915: {


1925:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1926:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1927:   if (!mat->ops->multtransposeadd) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
1928:   if (v1 == v3) SETERRQ(PETSC_ERR_ARG_IDN,"v1 and v3 must be different vectors");
1929:   if (mat->rmap->N != v1->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v1: global dim %D %D",mat->rmap->N,v1->map->N);
1930:   if (mat->cmap->N != v2->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v2: global dim %D %D",mat->cmap->N,v2->map->N);
1931:   if (mat->cmap->N != v3->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec v3: global dim %D %D",mat->cmap->N,v3->map->N);
1932:   MatPreallocated(mat);

1934:   PetscLogEventBegin(MAT_MultTransposeAdd,mat,v1,v2,v3);
1935:   (*mat->ops->multtransposeadd)(mat,v1,v2,v3);
1936:   PetscLogEventEnd(MAT_MultTransposeAdd,mat,v1,v2,v3);
1937:   PetscObjectStateIncrease((PetscObject)v3);
1938:   return(0);
1939: }

1943: /*@
1944:    MatMultConstrained - The inner multiplication routine for a
1945:    constrained matrix P^T A P.

1947:    Collective on Mat and Vec

1949:    Input Parameters:
1950: +  mat - the matrix
1951: -  x   - the vector to be multilplied

1953:    Output Parameters:
1954: .  y - the result

1956:    Notes:
1957:    The vectors x and y cannot be the same.  I.e., one cannot
1958:    call MatMult(A,y,y).

1960:    Level: beginner

1962: .keywords: matrix, multiply, matrix-vector product, constraint
1963: .seealso: MatMult(), MatMultTrans(), MatMultAdd(), MatMultTransAdd()
1964: @*/
1965: PetscErrorCode  MatMultConstrained(Mat mat,Vec x,Vec y)
1966: {

1973:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
1974:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
1975:   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
1976:   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
1977:   if (mat->rmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->rmap->N,y->map->N);
1978:   if (mat->rmap->n != y->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: local dim %D %D",mat->rmap->n,y->map->n);

1980:   PetscLogEventBegin(MAT_MultConstrained,mat,x,y,0);
1981:   (*mat->ops->multconstrained)(mat,x,y);
1982:   PetscLogEventEnd(MAT_MultConstrained,mat,x,y,0);
1983:   PetscObjectStateIncrease((PetscObject)y);

1985:   return(0);
1986: }

1990: /*@
1991:    MatMultTransposeConstrained - The inner multiplication routine for a
1992:    constrained matrix P^T A^T P.

1994:    Collective on Mat and Vec

1996:    Input Parameters:
1997: +  mat - the matrix
1998: -  x   - the vector to be multilplied

2000:    Output Parameters:
2001: .  y - the result

2003:    Notes:
2004:    The vectors x and y cannot be the same.  I.e., one cannot
2005:    call MatMult(A,y,y).

2007:    Level: beginner

2009: .keywords: matrix, multiply, matrix-vector product, constraint
2010: .seealso: MatMult(), MatMultTrans(), MatMultAdd(), MatMultTransAdd()
2011: @*/
2012: PetscErrorCode  MatMultTransposeConstrained(Mat mat,Vec x,Vec y)
2013: {

2020:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2021:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2022:   if (x == y) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"x and y must be different vectors");
2023:   if (mat->rmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2024:   if (mat->cmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->rmap->N,y->map->N);

2026:   PetscLogEventBegin(MAT_MultConstrained,mat,x,y,0);
2027:   (*mat->ops->multtransposeconstrained)(mat,x,y);
2028:   PetscLogEventEnd(MAT_MultConstrained,mat,x,y,0);
2029:   PetscObjectStateIncrease((PetscObject)y);

2031:   return(0);
2032: }
2033: /* ------------------------------------------------------------*/
2036: /*@
2037:    MatGetInfo - Returns information about matrix storage (number of
2038:    nonzeros, memory, etc.).

2040:    Collective on Mat if MAT_GLOBAL_MAX or MAT_GLOBAL_SUM is used
2041:    as the flag

2043:    Input Parameters:
2044: .  mat - the matrix

2046:    Output Parameters:
2047: +  flag - flag indicating the type of parameters to be returned
2048:    (MAT_LOCAL - local matrix, MAT_GLOBAL_MAX - maximum over all processors,
2049:    MAT_GLOBAL_SUM - sum over all processors)
2050: -  info - matrix information context

2052:    Notes:
2053:    The MatInfo context contains a variety of matrix data, including
2054:    number of nonzeros allocated and used, number of mallocs during
2055:    matrix assembly, etc.  Additional information for factored matrices
2056:    is provided (such as the fill ratio, number of mallocs during
2057:    factorization, etc.).  Much of this info is printed to PETSC_STDOUT
2058:    when using the runtime options 
2059: $       -info -mat_view_info

2061:    Example for C/C++ Users:
2062:    See the file ${PETSC_DIR}/include/petscmat.h for a complete list of
2063:    data within the MatInfo context.  For example, 
2064: .vb
2065:       MatInfo info;
2066:       Mat     A;
2067:       double  mal, nz_a, nz_u;

2069:       MatGetInfo(A,MAT_LOCAL,&info);
2070:       mal  = info.mallocs;
2071:       nz_a = info.nz_allocated;
2072: .ve

2074:    Example for Fortran Users:
2075:    Fortran users should declare info as a double precision
2076:    array of dimension MAT_INFO_SIZE, and then extract the parameters
2077:    of interest.  See the file ${PETSC_DIR}/include/finclude/petscmat.h
2078:    a complete list of parameter names.
2079: .vb
2080:       double  precision info(MAT_INFO_SIZE)
2081:       double  precision mal, nz_a
2082:       Mat     A
2083:       integer ierr

2085:       call MatGetInfo(A,MAT_LOCAL,info,ierr)
2086:       mal = info(MAT_INFO_MALLOCS)
2087:       nz_a = info(MAT_INFO_NZ_ALLOCATED)
2088: .ve

2090:     Level: intermediate

2092:     Concepts: matrices^getting information on
2093:  
2094: @*/
2095: PetscErrorCode  MatGetInfo(Mat mat,MatInfoType flag,MatInfo *info)
2096: {

2103:   if (!mat->ops->getinfo) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2104:   MatPreallocated(mat);
2105:   (*mat->ops->getinfo)(mat,flag,info);
2106:   return(0);
2107: }

2109: /* ----------------------------------------------------------*/
2112: /*@C  
2113:    MatILUDTFactor - Performs a drop tolerance ILU factorization.

2115:    Collective on Mat

2117:    Input Parameters:
2118: +  mat - the matrix
2119: .  row - row permutation
2120: .  col - column permutation
2121: -  info - information about the factorization to be done

2123:    Output Parameters:
2124: .  fact - the factored matrix

2126:    Level: developer

2128:    Notes:
2129:    Most users should employ the simplified KSP interface for linear solvers
2130:    instead of working directly with matrix algebra routines such as this.
2131:    See, e.g., KSPCreate().

2133:    This is currently only supported for the SeqAIJ matrix format using code
2134:    from Yousef Saad's SPARSEKIT2  package (translated to C with f2c) and/or
2135:    Matlab. SPARSEKIT2 is copyrighted by Yousef Saad with the GNU copyright
2136:    and thus can be distributed with PETSc.

2138:     Concepts: matrices^ILUDT factorization

2140: .seealso: MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
2141: @*/
2142: PetscErrorCode  MatILUDTFactor(Mat mat,IS row,IS col,const MatFactorInfo *info,Mat *fact)
2143: {

2153:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2154:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2155:   if (!mat->ops->iludtfactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2156:   MatPreallocated(mat);
2157:   PetscLogEventBegin(MAT_ILUFactor,mat,row,col,0);
2158:   (*mat->ops->iludtfactor)(mat,row,col,info,fact);
2159:   PetscLogEventEnd(MAT_ILUFactor,mat,row,col,0);
2160:   PetscObjectStateIncrease((PetscObject)*fact);

2162:   return(0);
2163: }

2167: /*@  
2168:    MatLUFactor - Performs in-place LU factorization of matrix.

2170:    Collective on Mat

2172:    Input Parameters:
2173: +  mat - the matrix
2174: .  row - row permutation
2175: .  col - column permutation
2176: -  info - options for factorization, includes 
2177: $          fill - expected fill as ratio of original fill.
2178: $          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
2179: $                   Run with the option -info to determine an optimal value to use

2181:    Notes:
2182:    Most users should employ the simplified KSP interface for linear solvers
2183:    instead of working directly with matrix algebra routines such as this.
2184:    See, e.g., KSPCreate().

2186:    This changes the state of the matrix to a factored matrix; it cannot be used
2187:    for example with MatSetValues() unless one first calls MatSetUnfactored().

2189:    Level: developer

2191:    Concepts: matrices^LU factorization

2193: .seealso: MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor(),
2194:           MatGetOrdering(), MatSetUnfactored(), MatFactorInfo

2196: @*/
2197: PetscErrorCode  MatLUFactor(Mat mat,IS row,IS col,const MatFactorInfo *info)
2198: {

2207:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2208:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2209:   if (!mat->ops->lufactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2210:   MatPreallocated(mat);

2212:   PetscLogEventBegin(MAT_LUFactor,mat,row,col,0);
2213:   (*mat->ops->lufactor)(mat,row,col,info);
2214:   PetscLogEventEnd(MAT_LUFactor,mat,row,col,0);
2215:   PetscObjectStateIncrease((PetscObject)mat);
2216:   return(0);
2217: }

2221: /*@  
2222:    MatILUFactor - Performs in-place ILU factorization of matrix.

2224:    Collective on Mat

2226:    Input Parameters:
2227: +  mat - the matrix
2228: .  row - row permutation
2229: .  col - column permutation
2230: -  info - structure containing 
2231: $      levels - number of levels of fill.
2232: $      expected fill - as ratio of original fill.
2233: $      1 or 0 - indicating force fill on diagonal (improves robustness for matrices
2234:                 missing diagonal entries)

2236:    Notes: 
2237:    Probably really in-place only when level of fill is zero, otherwise allocates
2238:    new space to store factored matrix and deletes previous memory.

2240:    Most users should employ the simplified KSP interface for linear solvers
2241:    instead of working directly with matrix algebra routines such as this.
2242:    See, e.g., KSPCreate().

2244:    Level: developer

2246:    Concepts: matrices^ILU factorization

2248: .seealso: MatILUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
2249: @*/
2250: PetscErrorCode  MatILUFactor(Mat mat,IS row,IS col,const MatFactorInfo *info)
2251: {

2260:   if (mat->rmap->N != mat->cmap->N) SETERRQ(PETSC_ERR_ARG_WRONG,"matrix must be square");
2261:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2262:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2263:   if (!mat->ops->ilufactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2264:   MatPreallocated(mat);

2266:   PetscLogEventBegin(MAT_ILUFactor,mat,row,col,0);
2267:   (*mat->ops->ilufactor)(mat,row,col,info);
2268:   PetscLogEventEnd(MAT_ILUFactor,mat,row,col,0);
2269:   PetscObjectStateIncrease((PetscObject)mat);
2270:   return(0);
2271: }

2275: /*@  
2276:    MatLUFactorSymbolic - Performs symbolic LU factorization of matrix.
2277:    Call this routine before calling MatLUFactorNumeric().

2279:    Collective on Mat

2281:    Input Parameters:
2282: +  fact - the factor matrix obtained with MatGetFactor()
2283: .  mat - the matrix
2284: .  row, col - row and column permutations
2285: -  info - options for factorization, includes 
2286: $          fill - expected fill as ratio of original fill.
2287: $          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
2288: $                   Run with the option -info to determine an optimal value to use


2291:    Notes:
2292:    See the users manual for additional information about
2293:    choosing the fill factor for better efficiency.

2295:    Most users should employ the simplified KSP interface for linear solvers
2296:    instead of working directly with matrix algebra routines such as this.
2297:    See, e.g., KSPCreate().

2299:    Level: developer

2301:    Concepts: matrices^LU symbolic factorization

2303: .seealso: MatLUFactor(), MatLUFactorNumeric(), MatCholeskyFactor(), MatFactorInfo
2304: @*/
2305: PetscErrorCode  MatLUFactorSymbolic(Mat fact,Mat mat,IS row,IS col,const MatFactorInfo *info)
2306: {

2316:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2317:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2318:   if (!(fact)->ops->lufactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s  symbolic LU",((PetscObject)mat)->type_name);
2319:   MatPreallocated(mat);

2321:   PetscLogEventBegin(MAT_LUFactorSymbolic,mat,row,col,0);
2322:   (fact->ops->lufactorsymbolic)(fact,mat,row,col,info);
2323:   PetscLogEventEnd(MAT_LUFactorSymbolic,mat,row,col,0);
2324:   PetscObjectStateIncrease((PetscObject)fact);
2325:   return(0);
2326: }

2330: /*@  
2331:    MatLUFactorNumeric - Performs numeric LU factorization of a matrix.
2332:    Call this routine after first calling MatLUFactorSymbolic().

2334:    Collective on Mat

2336:    Input Parameters:
2337: +  fact - the factor matrix obtained with MatGetFactor()
2338: .  mat - the matrix
2339: -  info - options for factorization

2341:    Notes:
2342:    See MatLUFactor() for in-place factorization.  See 
2343:    MatCholeskyFactorNumeric() for the symmetric, positive definite case.  

2345:    Most users should employ the simplified KSP interface for linear solvers
2346:    instead of working directly with matrix algebra routines such as this.
2347:    See, e.g., KSPCreate().

2349:    Level: developer

2351:    Concepts: matrices^LU numeric factorization

2353: .seealso: MatLUFactorSymbolic(), MatLUFactor(), MatCholeskyFactor()
2354: @*/
2355: PetscErrorCode  MatLUFactorNumeric(Mat fact,Mat mat,const MatFactorInfo *info)
2356: {

2364:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2365:   if (mat->rmap->N != (fact)->rmap->N || mat->cmap->N != (fact)->cmap->N) {
2366:     SETERRQ4(PETSC_ERR_ARG_SIZ,"Mat mat,Mat fact: global dimensions are different %D should = %D %D should = %D",mat->rmap->N,(fact)->rmap->N,mat->cmap->N,(fact)->cmap->N);
2367:   }
2368:   if (!(fact)->ops->lufactornumeric) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2369:   MatPreallocated(mat);
2370:   PetscLogEventBegin(MAT_LUFactorNumeric,mat,fact,0,0);
2371:   (fact->ops->lufactornumeric)(fact,mat,info);
2372:   PetscLogEventEnd(MAT_LUFactorNumeric,mat,fact,0,0);

2374:   MatView_Private(fact);
2375:   PetscObjectStateIncrease((PetscObject)fact);
2376:   return(0);
2377: }

2381: /*@  
2382:    MatCholeskyFactor - Performs in-place Cholesky factorization of a
2383:    symmetric matrix. 

2385:    Collective on Mat

2387:    Input Parameters:
2388: +  mat - the matrix
2389: .  perm - row and column permutations
2390: -  f - expected fill as ratio of original fill

2392:    Notes:
2393:    See MatLUFactor() for the nonsymmetric case.  See also
2394:    MatCholeskyFactorSymbolic(), and MatCholeskyFactorNumeric().

2396:    Most users should employ the simplified KSP interface for linear solvers
2397:    instead of working directly with matrix algebra routines such as this.
2398:    See, e.g., KSPCreate().

2400:    Level: developer

2402:    Concepts: matrices^Cholesky factorization

2404: .seealso: MatLUFactor(), MatCholeskyFactorSymbolic(), MatCholeskyFactorNumeric()
2405:           MatGetOrdering()

2407: @*/
2408: PetscErrorCode  MatCholeskyFactor(Mat mat,IS perm,const MatFactorInfo *info)
2409: {

2417:   if (mat->rmap->N != mat->cmap->N) SETERRQ(PETSC_ERR_ARG_WRONG,"Matrix must be square");
2418:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2419:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2420:   if (!mat->ops->choleskyfactor) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2421:   MatPreallocated(mat);

2423:   PetscLogEventBegin(MAT_CholeskyFactor,mat,perm,0,0);
2424:   (*mat->ops->choleskyfactor)(mat,perm,info);
2425:   PetscLogEventEnd(MAT_CholeskyFactor,mat,perm,0,0);
2426:   PetscObjectStateIncrease((PetscObject)mat);
2427:   return(0);
2428: }

2432: /*@  
2433:    MatCholeskyFactorSymbolic - Performs symbolic Cholesky factorization
2434:    of a symmetric matrix. 

2436:    Collective on Mat

2438:    Input Parameters:
2439: +  fact - the factor matrix obtained with MatGetFactor()
2440: .  mat - the matrix
2441: .  perm - row and column permutations
2442: -  info - options for factorization, includes 
2443: $          fill - expected fill as ratio of original fill.
2444: $          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
2445: $                   Run with the option -info to determine an optimal value to use

2447:    Notes:
2448:    See MatLUFactorSymbolic() for the nonsymmetric case.  See also
2449:    MatCholeskyFactor() and MatCholeskyFactorNumeric().

2451:    Most users should employ the simplified KSP interface for linear solvers
2452:    instead of working directly with matrix algebra routines such as this.
2453:    See, e.g., KSPCreate().

2455:    Level: developer

2457:    Concepts: matrices^Cholesky symbolic factorization

2459: .seealso: MatLUFactorSymbolic(), MatCholeskyFactor(), MatCholeskyFactorNumeric()
2460:           MatGetOrdering()

2462: @*/
2463: PetscErrorCode  MatCholeskyFactorSymbolic(Mat fact,Mat mat,IS perm,const MatFactorInfo *info)
2464: {

2473:   if (mat->rmap->N != mat->cmap->N) SETERRQ(PETSC_ERR_ARG_WRONG,"Matrix must be square");
2474:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2475:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
2476:   if (!(fact)->ops->choleskyfactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2477:   MatPreallocated(mat);

2479:   PetscLogEventBegin(MAT_CholeskyFactorSymbolic,mat,perm,0,0);
2480:   (fact->ops->choleskyfactorsymbolic)(fact,mat,perm,info);
2481:   PetscLogEventEnd(MAT_CholeskyFactorSymbolic,mat,perm,0,0);
2482:   PetscObjectStateIncrease((PetscObject)fact);
2483:   return(0);
2484: }

2488: /*@  
2489:    MatCholeskyFactorNumeric - Performs numeric Cholesky factorization
2490:    of a symmetric matrix. Call this routine after first calling
2491:    MatCholeskyFactorSymbolic().

2493:    Collective on Mat

2495:    Input Parameters:
2496: +  fact - the factor matrix obtained with MatGetFactor()
2497: .  mat - the initial matrix
2498: .  info - options for factorization
2499: -  fact - the symbolic factor of mat


2502:    Notes:
2503:    Most users should employ the simplified KSP interface for linear solvers
2504:    instead of working directly with matrix algebra routines such as this.
2505:    See, e.g., KSPCreate().

2507:    Level: developer

2509:    Concepts: matrices^Cholesky numeric factorization

2511: .seealso: MatCholeskyFactorSymbolic(), MatCholeskyFactor(), MatLUFactorNumeric()
2512: @*/
2513: PetscErrorCode  MatCholeskyFactorNumeric(Mat fact,Mat mat,const MatFactorInfo *info)
2514: {

2522:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
2523:   if (!(fact)->ops->choleskyfactornumeric) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2524:   if (mat->rmap->N != (fact)->rmap->N || mat->cmap->N != (fact)->cmap->N) {
2525:     SETERRQ4(PETSC_ERR_ARG_SIZ,"Mat mat,Mat fact: global dim %D should = %D %D should = %D",mat->rmap->N,(fact)->rmap->N,mat->cmap->N,(fact)->cmap->N);
2526:   }
2527:   MatPreallocated(mat);

2529:   PetscLogEventBegin(MAT_CholeskyFactorNumeric,mat,fact,0,0);
2530:   (fact->ops->choleskyfactornumeric)(fact,mat,info);
2531:   PetscLogEventEnd(MAT_CholeskyFactorNumeric,mat,fact,0,0);

2533:   MatView_Private(fact);
2534:   PetscObjectStateIncrease((PetscObject)fact);
2535:   return(0);
2536: }

2538: /* ----------------------------------------------------------------*/
2541: /*@
2542:    MatSolve - Solves A x = b, given a factored matrix.

2544:    Collective on Mat and Vec

2546:    Input Parameters:
2547: +  mat - the factored matrix
2548: -  b - the right-hand-side vector

2550:    Output Parameter:
2551: .  x - the result vector

2553:    Notes:
2554:    The vectors b and x cannot be the same.  I.e., one cannot
2555:    call MatSolve(A,x,x).

2557:    Notes:
2558:    Most users should employ the simplified KSP interface for linear solvers
2559:    instead of working directly with matrix algebra routines such as this.
2560:    See, e.g., KSPCreate().

2562:    Level: developer

2564:    Concepts: matrices^triangular solves

2566: .seealso: MatSolveAdd(), MatSolveTranspose(), MatSolveTransposeAdd()
2567: @*/
2568: PetscErrorCode  MatSolve(Mat mat,Vec b,Vec x)
2569: {

2579:   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2580:   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2581:   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2582:   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
2583:   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
2584:   if (!mat->rmap->N && !mat->cmap->N) return(0);
2585:   if (!mat->ops->solve) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2586:   MatPreallocated(mat);

2588:   PetscLogEventBegin(MAT_Solve,mat,b,x,0);
2589:   (*mat->ops->solve)(mat,b,x);
2590:   PetscLogEventEnd(MAT_Solve,mat,b,x,0);
2591:   PetscObjectStateIncrease((PetscObject)x);
2592:   return(0);
2593: }

2597: PetscErrorCode  MatMatSolve_Basic(Mat A,Mat B,Mat X)
2598: {
2600:   Vec            b,x;
2601:   PetscInt       m,N,i;
2602:   PetscScalar    *bb,*xx;

2605:   MatGetArray(B,&bb);
2606:   MatGetArray(X,&xx);
2607:   MatGetLocalSize(B,&m,PETSC_NULL);  /* number local rows */
2608:   MatGetSize(B,PETSC_NULL,&N);       /* total columns in dense matrix */
2609:   VecCreateMPIWithArray(((PetscObject)A)->comm,m,PETSC_DETERMINE,PETSC_NULL,&b);
2610:   VecCreateMPIWithArray(((PetscObject)A)->comm,m,PETSC_DETERMINE,PETSC_NULL,&x);
2611:   for (i=0; i<N; i++) {
2612:     VecPlaceArray(b,bb + i*m);
2613:     VecPlaceArray(x,xx + i*m);
2614:     MatSolve(A,b,x);
2615:     VecResetArray(x);
2616:     VecResetArray(b);
2617:   }
2618:   VecDestroy(b);
2619:   VecDestroy(x);
2620:   MatRestoreArray(B,&bb);
2621:   MatRestoreArray(X,&xx);
2622:   return(0);
2623: }

2627: /*@
2628:    MatMatSolve - Solves A X = B, given a factored matrix.

2630:    Collective on Mat 

2632:    Input Parameters:
2633: +  mat - the factored matrix
2634: -  B - the right-hand-side matrix  (dense matrix)

2636:    Output Parameter:
2637: .  X - the result matrix (dense matrix)

2639:    Notes:
2640:    The matrices b and x cannot be the same.  I.e., one cannot
2641:    call MatMatSolve(A,x,x).

2643:    Notes:
2644:    Most users should usually employ the simplified KSP interface for linear solvers
2645:    instead of working directly with matrix algebra routines such as this.
2646:    See, e.g., KSPCreate(). However KSP can only solve for one vector (column of X)
2647:    at a time.

2649:    Level: developer

2651:    Concepts: matrices^triangular solves

2653: .seealso: MatMatSolveAdd(), MatMatSolveTranspose(), MatMatSolveTransposeAdd(), MatLUFactor(), MatCholeskyFactor()
2654: @*/
2655: PetscErrorCode  MatMatSolve(Mat A,Mat B,Mat X)
2656: {

2666:   if (X == B) SETERRQ(PETSC_ERR_ARG_IDN,"X and B must be different matrices");
2667:   if (!A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2668:   if (A->cmap->N != X->rmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat A,Mat X: global dim %D %D",A->cmap->N,X->rmap->N);
2669:   if (A->rmap->N != B->rmap->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat A,Mat B: global dim %D %D",A->rmap->N,B->rmap->N);
2670:   if (A->rmap->n != B->rmap->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat A,Mat B: local dim %D %D",A->rmap->n,B->rmap->n);
2671:   if (!A->rmap->N && !A->cmap->N) return(0);
2672:   MatPreallocated(A);

2674:   PetscLogEventBegin(MAT_MatSolve,A,B,X,0);
2675:   if (!A->ops->matsolve) {
2676:     PetscInfo1(A,"Mat type %s using basic MatMatSolve",((PetscObject)A)->type_name);
2677:     MatMatSolve_Basic(A,B,X);
2678:   } else {
2679:     (*A->ops->matsolve)(A,B,X);
2680:   }
2681:   PetscLogEventEnd(MAT_MatSolve,A,B,X,0);
2682:   PetscObjectStateIncrease((PetscObject)X);
2683:   return(0);
2684: }


2689: /* @
2690:    MatForwardSolve - Solves L x = b, given a factored matrix, A = LU, or
2691:                             U^T*D^(1/2) x = b, given a factored symmetric matrix, A = U^T*D*U,

2693:    Collective on Mat and Vec

2695:    Input Parameters:
2696: +  mat - the factored matrix
2697: -  b - the right-hand-side vector

2699:    Output Parameter:
2700: .  x - the result vector

2702:    Notes:
2703:    MatSolve() should be used for most applications, as it performs
2704:    a forward solve followed by a backward solve.

2706:    The vectors b and x cannot be the same,  i.e., one cannot
2707:    call MatForwardSolve(A,x,x).

2709:    For matrix in seqsbaij format with block size larger than 1,
2710:    the diagonal blocks are not implemented as D = D^(1/2) * D^(1/2) yet.
2711:    MatForwardSolve() solves U^T*D y = b, and
2712:    MatBackwardSolve() solves U x = y.
2713:    Thus they do not provide a symmetric preconditioner.

2715:    Most users should employ the simplified KSP interface for linear solvers
2716:    instead of working directly with matrix algebra routines such as this.
2717:    See, e.g., KSPCreate().

2719:    Level: developer

2721:    Concepts: matrices^forward solves

2723: .seealso: MatSolve(), MatBackwardSolve()
2724: @ */
2725: PetscErrorCode  MatForwardSolve(Mat mat,Vec b,Vec x)
2726: {

2736:   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2737:   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2738:   if (!mat->ops->forwardsolve) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2739:   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2740:   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
2741:   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
2742:   MatPreallocated(mat);
2743:   PetscLogEventBegin(MAT_ForwardSolve,mat,b,x,0);
2744:   (*mat->ops->forwardsolve)(mat,b,x);
2745:   PetscLogEventEnd(MAT_ForwardSolve,mat,b,x,0);
2746:   PetscObjectStateIncrease((PetscObject)x);
2747:   return(0);
2748: }

2752: /* @
2753:    MatBackwardSolve - Solves U x = b, given a factored matrix, A = LU.
2754:                              D^(1/2) U x = b, given a factored symmetric matrix, A = U^T*D*U,

2756:    Collective on Mat and Vec

2758:    Input Parameters:
2759: +  mat - the factored matrix
2760: -  b - the right-hand-side vector

2762:    Output Parameter:
2763: .  x - the result vector

2765:    Notes:
2766:    MatSolve() should be used for most applications, as it performs
2767:    a forward solve followed by a backward solve.

2769:    The vectors b and x cannot be the same.  I.e., one cannot
2770:    call MatBackwardSolve(A,x,x).

2772:    For matrix in seqsbaij format with block size larger than 1,
2773:    the diagonal blocks are not implemented as D = D^(1/2) * D^(1/2) yet.
2774:    MatForwardSolve() solves U^T*D y = b, and
2775:    MatBackwardSolve() solves U x = y.
2776:    Thus they do not provide a symmetric preconditioner.

2778:    Most users should employ the simplified KSP interface for linear solvers
2779:    instead of working directly with matrix algebra routines such as this.
2780:    See, e.g., KSPCreate().

2782:    Level: developer

2784:    Concepts: matrices^backward solves

2786: .seealso: MatSolve(), MatForwardSolve()
2787: @ */
2788: PetscErrorCode  MatBackwardSolve(Mat mat,Vec b,Vec x)
2789: {

2799:   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2800:   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2801:   if (!mat->ops->backwardsolve) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
2802:   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2803:   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
2804:   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
2805:   MatPreallocated(mat);

2807:   PetscLogEventBegin(MAT_BackwardSolve,mat,b,x,0);
2808:   (*mat->ops->backwardsolve)(mat,b,x);
2809:   PetscLogEventEnd(MAT_BackwardSolve,mat,b,x,0);
2810:   PetscObjectStateIncrease((PetscObject)x);
2811:   return(0);
2812: }

2816: /*@
2817:    MatSolveAdd - Computes x = y + inv(A)*b, given a factored matrix.

2819:    Collective on Mat and Vec

2821:    Input Parameters:
2822: +  mat - the factored matrix
2823: .  b - the right-hand-side vector
2824: -  y - the vector to be added to 

2826:    Output Parameter:
2827: .  x - the result vector

2829:    Notes:
2830:    The vectors b and x cannot be the same.  I.e., one cannot
2831:    call MatSolveAdd(A,x,y,x).

2833:    Most users should employ the simplified KSP interface for linear solvers
2834:    instead of working directly with matrix algebra routines such as this.
2835:    See, e.g., KSPCreate().

2837:    Level: developer

2839:    Concepts: matrices^triangular solves

2841: .seealso: MatSolve(), MatSolveTranspose(), MatSolveTransposeAdd()
2842: @*/
2843: PetscErrorCode  MatSolveAdd(Mat mat,Vec b,Vec y,Vec x)
2844: {
2845:   PetscScalar    one = 1.0;
2846:   Vec            tmp;

2858:   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2859:   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2860:   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
2861:   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
2862:   if (mat->rmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->rmap->N,y->map->N);
2863:   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
2864:   if (x->map->n != y->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Vec x,Vec y: local dim %D %D",x->map->n,y->map->n);
2865:   MatPreallocated(mat);

2867:   PetscLogEventBegin(MAT_SolveAdd,mat,b,x,y);
2868:   if (mat->ops->solveadd)  {
2869:     (*mat->ops->solveadd)(mat,b,y,x);
2870:   } else {
2871:     /* do the solve then the add manually */
2872:     if (x != y) {
2873:       MatSolve(mat,b,x);
2874:       VecAXPY(x,one,y);
2875:     } else {
2876:       VecDuplicate(x,&tmp);
2877:       PetscLogObjectParent(mat,tmp);
2878:       VecCopy(x,tmp);
2879:       MatSolve(mat,b,x);
2880:       VecAXPY(x,one,tmp);
2881:       VecDestroy(tmp);
2882:     }
2883:   }
2884:   PetscLogEventEnd(MAT_SolveAdd,mat,b,x,y);
2885:   PetscObjectStateIncrease((PetscObject)x);
2886:   return(0);
2887: }

2891: /*@
2892:    MatSolveTranspose - Solves A' x = b, given a factored matrix.

2894:    Collective on Mat and Vec

2896:    Input Parameters:
2897: +  mat - the factored matrix
2898: -  b - the right-hand-side vector

2900:    Output Parameter:
2901: .  x - the result vector

2903:    Notes:
2904:    The vectors b and x cannot be the same.  I.e., one cannot
2905:    call MatSolveTranspose(A,x,x).

2907:    Most users should employ the simplified KSP interface for linear solvers
2908:    instead of working directly with matrix algebra routines such as this.
2909:    See, e.g., KSPCreate().

2911:    Level: developer

2913:    Concepts: matrices^triangular solves

2915: .seealso: MatSolve(), MatSolveAdd(), MatSolveTransposeAdd()
2916: @*/
2917: PetscErrorCode  MatSolveTranspose(Mat mat,Vec b,Vec x)
2918: {

2928:   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2929:   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2930:   if (!mat->ops->solvetranspose) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s",((PetscObject)mat)->type_name);
2931:   if (mat->rmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->rmap->N,x->map->N);
2932:   if (mat->cmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->cmap->N,b->map->N);
2933:   MatPreallocated(mat);
2934:   PetscLogEventBegin(MAT_SolveTranspose,mat,b,x,0);
2935:   (*mat->ops->solvetranspose)(mat,b,x);
2936:   PetscLogEventEnd(MAT_SolveTranspose,mat,b,x,0);
2937:   PetscObjectStateIncrease((PetscObject)x);
2938:   return(0);
2939: }

2943: /*@
2944:    MatSolveTransposeAdd - Computes x = y + inv(Transpose(A)) b, given a 
2945:                       factored matrix. 

2947:    Collective on Mat and Vec

2949:    Input Parameters:
2950: +  mat - the factored matrix
2951: .  b - the right-hand-side vector
2952: -  y - the vector to be added to 

2954:    Output Parameter:
2955: .  x - the result vector

2957:    Notes:
2958:    The vectors b and x cannot be the same.  I.e., one cannot
2959:    call MatSolveTransposeAdd(A,x,y,x).

2961:    Most users should employ the simplified KSP interface for linear solvers
2962:    instead of working directly with matrix algebra routines such as this.
2963:    See, e.g., KSPCreate().

2965:    Level: developer

2967:    Concepts: matrices^triangular solves

2969: .seealso: MatSolve(), MatSolveAdd(), MatSolveTranspose()
2970: @*/
2971: PetscErrorCode  MatSolveTransposeAdd(Mat mat,Vec b,Vec y,Vec x)
2972: {
2973:   PetscScalar    one = 1.0;
2975:   Vec            tmp;

2986:   if (x == b) SETERRQ(PETSC_ERR_ARG_IDN,"x and b must be different vectors");
2987:   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Unfactored matrix");
2988:   if (mat->rmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->rmap->N,x->map->N);
2989:   if (mat->cmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->cmap->N,b->map->N);
2990:   if (mat->cmap->N != y->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec y: global dim %D %D",mat->cmap->N,y->map->N);
2991:   if (x->map->n != y->map->n)   SETERRQ2(PETSC_ERR_ARG_SIZ,"Vec x,Vec y: local dim %D %D",x->map->n,y->map->n);
2992:   MatPreallocated(mat);

2994:   PetscLogEventBegin(MAT_SolveTransposeAdd,mat,b,x,y);
2995:   if (mat->ops->solvetransposeadd) {
2996:     (*mat->ops->solvetransposeadd)(mat,b,y,x);
2997:   } else {
2998:     /* do the solve then the add manually */
2999:     if (x != y) {
3000:       MatSolveTranspose(mat,b,x);
3001:       VecAXPY(x,one,y);
3002:     } else {
3003:       VecDuplicate(x,&tmp);
3004:       PetscLogObjectParent(mat,tmp);
3005:       VecCopy(x,tmp);
3006:       MatSolveTranspose(mat,b,x);
3007:       VecAXPY(x,one,tmp);
3008:       VecDestroy(tmp);
3009:     }
3010:   }
3011:   PetscLogEventEnd(MAT_SolveTransposeAdd,mat,b,x,y);
3012:   PetscObjectStateIncrease((PetscObject)x);
3013:   return(0);
3014: }
3015: /* ----------------------------------------------------------------*/

3019: /*@
3020:    MatRelax - Computes relaxation (SOR, Gauss-Seidel) sweeps.

3022:    Collective on Mat and Vec

3024:    Input Parameters:
3025: +  mat - the matrix
3026: .  b - the right hand side
3027: .  omega - the relaxation factor
3028: .  flag - flag indicating the type of SOR (see below)
3029: .  shift -  diagonal shift
3030: .  its - the number of iterations
3031: -  lits - the number of local iterations 

3033:    Output Parameters:
3034: .  x - the solution (can contain an initial guess)

3036:    SOR Flags:
3037: .     SOR_FORWARD_SWEEP - forward SOR
3038: .     SOR_BACKWARD_SWEEP - backward SOR
3039: .     SOR_SYMMETRIC_SWEEP - SSOR (symmetric SOR)
3040: .     SOR_LOCAL_FORWARD_SWEEP - local forward SOR 
3041: .     SOR_LOCAL_BACKWARD_SWEEP - local forward SOR 
3042: .     SOR_LOCAL_SYMMETRIC_SWEEP - local SSOR
3043: .     SOR_APPLY_UPPER, SOR_APPLY_LOWER - applies 
3044:          upper/lower triangular part of matrix to
3045:          vector (with omega)
3046: .     SOR_ZERO_INITIAL_GUESS - zero initial guess

3048:    Notes:
3049:    SOR_LOCAL_FORWARD_SWEEP, SOR_LOCAL_BACKWARD_SWEEP, and
3050:    SOR_LOCAL_SYMMETRIC_SWEEP perform separate independent smoothings
3051:    on each processor. 

3053:    Application programmers will not generally use MatRelax() directly,
3054:    but instead will employ the KSP/PC interface.

3056:    Notes for Advanced Users:
3057:    The flags are implemented as bitwise inclusive or operations.
3058:    For example, use (SOR_ZERO_INITIAL_GUESS | SOR_SYMMETRIC_SWEEP)
3059:    to specify a zero initial guess for SSOR.

3061:    Most users should employ the simplified KSP interface for linear solvers
3062:    instead of working directly with matrix algebra routines such as this.
3063:    See, e.g., KSPCreate().

3065:    See also, MatPBRelax(). This routine will automatically call the point block
3066:    version if the point version is not available.

3068:    Level: developer

3070:    Concepts: matrices^relaxation
3071:    Concepts: matrices^SOR
3072:    Concepts: matrices^Gauss-Seidel

3074: @*/
3075: PetscErrorCode  MatRelax(Mat mat,Vec b,PetscReal omega,MatSORType flag,PetscReal shift,PetscInt its,PetscInt lits,Vec x)
3076: {

3086:   if (!mat->ops->relax && !mat->ops->pbrelax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3087:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3088:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3089:   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
3090:   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
3091:   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
3092:   if (its <= 0) SETERRQ1(PETSC_ERR_ARG_WRONG,"Relaxation requires global its %D positive",its);
3093:   if (lits <= 0) SETERRQ1(PETSC_ERR_ARG_WRONG,"Relaxation requires local its %D positive",lits);

3095:   MatPreallocated(mat);
3096:   PetscLogEventBegin(MAT_Relax,mat,b,x,0);
3097:   if (mat->ops->relax) {
3098:     ierr =(*mat->ops->relax)(mat,b,omega,flag,shift,its,lits,x);
3099:   } else {
3100:     ierr =(*mat->ops->pbrelax)(mat,b,omega,flag,shift,its,lits,x);
3101:   }
3102:   PetscLogEventEnd(MAT_Relax,mat,b,x,0);
3103:   PetscObjectStateIncrease((PetscObject)x);
3104:   return(0);
3105: }

3109: /*@
3110:    MatPBRelax - Computes relaxation (SOR, Gauss-Seidel) sweeps.

3112:    Collective on Mat and Vec

3114:    See MatRelax() for usage

3116:    For multi-component PDEs where the Jacobian is stored in a point block format
3117:    (with the PETSc BAIJ matrix formats) the relaxation is done one point block at 
3118:    a time. That is, the small (for example, 4 by 4) blocks along the diagonal are solved
3119:    simultaneously (that is a 4 by 4 linear solve is done) to update all the values at a point.

3121:    Level: developer

3123: @*/
3124: PetscErrorCode  MatPBRelax(Mat mat,Vec b,PetscReal omega,MatSORType flag,PetscReal shift,PetscInt its,PetscInt lits,Vec x)
3125: {

3135:   if (!mat->ops->pbrelax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3136:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3137:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3138:   if (mat->cmap->N != x->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec x: global dim %D %D",mat->cmap->N,x->map->N);
3139:   if (mat->rmap->N != b->map->N) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: global dim %D %D",mat->rmap->N,b->map->N);
3140:   if (mat->rmap->n != b->map->n) SETERRQ2(PETSC_ERR_ARG_SIZ,"Mat mat,Vec b: local dim %D %D",mat->rmap->n,b->map->n);
3141:   MatPreallocated(mat);

3143:   PetscLogEventBegin(MAT_Relax,mat,b,x,0);
3144:   ierr =(*mat->ops->pbrelax)(mat,b,omega,flag,shift,its,lits,x);
3145:   PetscLogEventEnd(MAT_Relax,mat,b,x,0);
3146:   PetscObjectStateIncrease((PetscObject)x);
3147:   return(0);
3148: }

3152: /*
3153:       Default matrix copy routine.
3154: */
3155: PetscErrorCode MatCopy_Basic(Mat A,Mat B,MatStructure str)
3156: {
3157:   PetscErrorCode    ierr;
3158:   PetscInt          i,rstart,rend,nz;
3159:   const PetscInt    *cwork;
3160:   const PetscScalar *vwork;

3163:   if (B->assembled) {
3164:     MatZeroEntries(B);
3165:   }
3166:   MatGetOwnershipRange(A,&rstart,&rend);
3167:   for (i=rstart; i<rend; i++) {
3168:     MatGetRow(A,i,&nz,&cwork,&vwork);
3169:     MatSetValues(B,1,&i,nz,cwork,vwork,INSERT_VALUES);
3170:     MatRestoreRow(A,i,&nz,&cwork,&vwork);
3171:   }
3172:   MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
3173:   MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);
3174:   PetscObjectStateIncrease((PetscObject)B);
3175:   return(0);
3176: }

3180: /*@
3181:    MatCopy - Copys a matrix to another matrix.

3183:    Collective on Mat

3185:    Input Parameters:
3186: +  A - the matrix
3187: -  str - SAME_NONZERO_PATTERN or DIFFERENT_NONZERO_PATTERN

3189:    Output Parameter:
3190: .  B - where the copy is put

3192:    Notes:
3193:    If you use SAME_NONZERO_PATTERN then the two matrices had better have the 
3194:    same nonzero pattern or the routine will crash.

3196:    MatCopy() copies the matrix entries of a matrix to another existing
3197:    matrix (after first zeroing the second matrix).  A related routine is
3198:    MatConvert(), which first creates a new matrix and then copies the data.

3200:    Level: intermediate
3201:    
3202:    Concepts: matrices^copying

3204: .seealso: MatConvert(), MatDuplicate()

3206: @*/
3207: PetscErrorCode  MatCopy(Mat A,Mat B,MatStructure str)
3208: {
3210:   PetscInt       i;

3218:   MatPreallocated(B);
3219:   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3220:   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3221:   if (A->rmap->N != B->rmap->N || A->cmap->N != B->cmap->N) SETERRQ4(PETSC_ERR_ARG_SIZ,"Mat A,Mat B: global dim (%D,%D) (%D,%D)",A->rmap->N,B->rmap->N,A->cmap->N,B->cmap->N);
3222:   MatPreallocated(A);

3224:   PetscLogEventBegin(MAT_Copy,A,B,0,0);
3225:   if (A->ops->copy) {
3226:     (*A->ops->copy)(A,B,str);
3227:   } else { /* generic conversion */
3228:     MatCopy_Basic(A,B,str);
3229:   }
3230:   if (A->mapping) {
3231:     if (B->mapping) {ISLocalToGlobalMappingDestroy(B->mapping);B->mapping = 0;}
3232:     MatSetLocalToGlobalMapping(B,A->mapping);
3233:   }
3234:   if (A->bmapping) {
3235:     if (B->bmapping) {ISLocalToGlobalMappingDestroy(B->bmapping);B->bmapping = 0;}
3236:     MatSetLocalToGlobalMappingBlock(B,A->mapping);
3237:   }

3239:   B->stencil.dim = A->stencil.dim;
3240:   B->stencil.noc = A->stencil.noc;
3241:   for (i=0; i<=A->stencil.dim; i++) {
3242:     B->stencil.dims[i]   = A->stencil.dims[i];
3243:     B->stencil.starts[i] = A->stencil.starts[i];
3244:   }

3246:   PetscLogEventEnd(MAT_Copy,A,B,0,0);
3247:   PetscObjectStateIncrease((PetscObject)B);
3248:   return(0);
3249: }

3253: /*@C  
3254:    MatConvert - Converts a matrix to another matrix, either of the same
3255:    or different type.

3257:    Collective on Mat

3259:    Input Parameters:
3260: +  mat - the matrix
3261: .  newtype - new matrix type.  Use MATSAME to create a new matrix of the
3262:    same type as the original matrix.
3263: -  reuse - denotes if the destination matrix is to be created or reused.  Currently
3264:    MAT_REUSE_MATRIX is only supported for inplace conversion, otherwise use
3265:    MAT_INITIAL_MATRIX.

3267:    Output Parameter:
3268: .  M - pointer to place new matrix

3270:    Notes:
3271:    MatConvert() first creates a new matrix and then copies the data from
3272:    the first matrix.  A related routine is MatCopy(), which copies the matrix
3273:    entries of one matrix to another already existing matrix context.

3275:    Cannot be used to convert a sequential matrix to parallel or parallel to sequential,
3276:    the MPI communicator of the generated matrix is always the same as the communicator
3277:    of the input matrix.

3279:    Level: intermediate

3281:    Concepts: matrices^converting between storage formats

3283: .seealso: MatCopy(), MatDuplicate()
3284: @*/
3285: PetscErrorCode  MatConvert(Mat mat, const MatType newtype,MatReuse reuse,Mat *M)
3286: {
3287:   PetscErrorCode         ierr;
3288:   PetscTruth             sametype,issame,flg;
3289:   char                   convname[256],mtype[256];
3290:   Mat                    B;

3296:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3297:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3298:   MatPreallocated(mat);

3300:   PetscOptionsGetString(((PetscObject)mat)->prefix,"-matconvert_type",mtype,256,&flg);
3301:   if (flg) {
3302:     newtype = mtype;
3303:   }
3304:   PetscTypeCompare((PetscObject)mat,newtype,&sametype);
3305:   PetscStrcmp(newtype,"same",&issame);
3306:   if ((reuse == MAT_REUSE_MATRIX) && (mat != *M)) {
3307:     SETERRQ(PETSC_ERR_SUP,"MAT_REUSE_MATRIX only supported for in-place conversion currently");
3308:   }

3310:   if ((reuse == MAT_REUSE_MATRIX) && (issame || sametype)) return(0);
3311: 
3312:   if ((sametype || issame) && (reuse==MAT_INITIAL_MATRIX) && mat->ops->duplicate) {
3313:     (*mat->ops->duplicate)(mat,MAT_COPY_VALUES,M);
3314:   } else {
3315:     PetscErrorCode (*conv)(Mat, const MatType,MatReuse,Mat*)=PETSC_NULL;
3316:     const char     *prefix[3] = {"seq","mpi",""};
3317:     PetscInt       i;
3318:     /* 
3319:        Order of precedence:
3320:        1) See if a specialized converter is known to the current matrix.
3321:        2) See if a specialized converter is known to the desired matrix class.
3322:        3) See if a good general converter is registered for the desired class
3323:           (as of 6/27/03 only MATMPIADJ falls into this category).
3324:        4) See if a good general converter is known for the current matrix.
3325:        5) Use a really basic converter.
3326:     */
3327: 
3328:     /* 1) See if a specialized converter is known to the current matrix and the desired class */
3329:     for (i=0; i<3; i++) {
3330:       PetscStrcpy(convname,"MatConvert_");
3331:       PetscStrcat(convname,((PetscObject)mat)->type_name);
3332:       PetscStrcat(convname,"_");
3333:       PetscStrcat(convname,prefix[i]);
3334:       PetscStrcat(convname,newtype);
3335:       PetscStrcat(convname,"_C");
3336:       PetscObjectQueryFunction((PetscObject)mat,convname,(void (**)(void))&conv);
3337:       if (conv) goto foundconv;
3338:     }

3340:     /* 2)  See if a specialized converter is known to the desired matrix class. */
3341:     MatCreate(((PetscObject)mat)->comm,&B);
3342:     MatSetSizes(B,mat->rmap->n,mat->cmap->n,mat->rmap->N,mat->cmap->N);
3343:     MatSetType(B,newtype);
3344:     for (i=0; i<3; i++) {
3345:       PetscStrcpy(convname,"MatConvert_");
3346:       PetscStrcat(convname,((PetscObject)mat)->type_name);
3347:       PetscStrcat(convname,"_");
3348:       PetscStrcat(convname,prefix[i]);
3349:       PetscStrcat(convname,newtype);
3350:       PetscStrcat(convname,"_C");
3351:       PetscObjectQueryFunction((PetscObject)B,convname,(void (**)(void))&conv);
3352:       if (conv) {
3353:         MatDestroy(B);
3354:         goto foundconv;
3355:       }
3356:     }

3358:     /* 3) See if a good general converter is registered for the desired class */
3359:     conv = B->ops->convertfrom;
3360:     MatDestroy(B);
3361:     if (conv) goto foundconv;

3363:     /* 4) See if a good general converter is known for the current matrix */
3364:     if (mat->ops->convert) {
3365:       conv = mat->ops->convert;
3366:     }
3367:     if (conv) goto foundconv;

3369:     /* 5) Use a really basic converter. */
3370:     conv = MatConvert_Basic;

3372:     foundconv:
3373:     PetscLogEventBegin(MAT_Convert,mat,0,0,0);
3374:     (*conv)(mat,newtype,reuse,M);
3375:     PetscLogEventEnd(MAT_Convert,mat,0,0,0);
3376:   }
3377:   PetscObjectStateIncrease((PetscObject)*M);
3378:   return(0);
3379: }

3383: /*@C  
3384:    MatFactorGetSolverPackage - Returns name of the package providing the factorization routines

3386:    Not Collective

3388:    Input Parameter:
3389: .  mat - the matrix, must be a factored matrix

3391:    Output Parameter:
3392: .   type - the string name of the package (do not free this string)

3394:    Notes:
3395:       In Fortran you pass in a empty string and the package name will be copied into it. 
3396:     (Make sure the string is long enough)

3398:    Level: intermediate

3400: .seealso: MatCopy(), MatDuplicate(), MatGetFactorAvailable(), MatGetFactor()
3401: @*/
3402: PetscErrorCode  MatFactorGetSolverPackage(Mat mat, const MatSolverPackage *type)
3403: {
3404:   PetscErrorCode         ierr;
3405:   PetscErrorCode         (*conv)(Mat,const MatSolverPackage*);

3410:   if (!mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Only for factored matrix");
3411:   PetscObjectQueryFunction((PetscObject)mat,"MatFactorGetSolverPackage_C",(void (**)(void))&conv);
3412:   if (!conv) {
3413:     *type = MAT_SOLVER_PETSC;
3414:   } else {
3415:     (*conv)(mat,type);
3416:   }
3417:   return(0);
3418: }

3422: /*@C  
3423:    MatGetFactor - Returns a matrix suitable to calls to MatXXFactorSymbolic()

3425:    Collective on Mat

3427:    Input Parameters:
3428: +  mat - the matrix
3429: .  type - name of solver type, for example, spooles, superlu, plapack, petsc (to use PETSc's default)
3430: -  ftype - factor type, MAT_FACTOR_LU, MAT_FACTOR_CHOLESKY, MAT_FACTOR_ICC, MAT_FACTOR_ILU, 

3432:    Output Parameters:
3433: .  f - the factor matrix used with MatXXFactorSymbolic() calls 

3435:    Notes:
3436:       Some PETSc matrix formats have alternative solvers available that are contained in alternative packages
3437:      such as pastix, superlu, mumps, spooles etc. 

3439:       PETSc must have been config/configure.py to use the external solver, using the option --download-package

3441:    Level: intermediate

3443: .seealso: MatCopy(), MatDuplicate(), MatGetFactorAvailable()
3444: @*/
3445: PetscErrorCode  MatGetFactor(Mat mat, const MatSolverPackage type,MatFactorType ftype,Mat *f)
3446: {
3447:   PetscErrorCode         ierr;
3448:   char                   convname[256];
3449:   PetscErrorCode         (*conv)(Mat,MatFactorType,Mat*);


3455:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3456:   MatPreallocated(mat);

3458:   PetscStrcpy(convname,"MatGetFactor_");
3459:   PetscStrcat(convname,((PetscObject)mat)->type_name);
3460:   PetscStrcat(convname,"_");
3461:   PetscStrcat(convname,type);
3462:   PetscStrcat(convname,"_C");
3463:   PetscObjectQueryFunction((PetscObject)mat,convname,(void (**)(void))&conv);
3464:   if (!conv) {
3465:     PetscTruth flag;
3466:     PetscStrcasecmp(MAT_SOLVER_PETSC,type,&flag);
3467:     if (flag) {
3468:       SETERRQ1(PETSC_ERR_SUP,"Matrix format %s does not have a built-in PETSc direct solver",((PetscObject)mat)->type_name);
3469:     } else {
3470:       SETERRQ3(PETSC_ERR_SUP,"Matrix format %s does not have a solver %s. Perhaps you must config/configure.py with --download-%s",((PetscObject)mat)->type_name,type,type);
3471:     }
3472:   }
3473:   (*conv)(mat,ftype,f);
3474:   return(0);
3475: }

3479: /*@C  
3480:    MatGetFactorAvailable - Returns a a flag if matrix supports particular package and factor type

3482:    Collective on Mat

3484:    Input Parameters:
3485: +  mat - the matrix
3486: .  type - name of solver type, for example, spooles, superlu, plapack, petsc (to use PETSc's default)
3487: -  ftype - factor type, MAT_FACTOR_LU, MAT_FACTOR_CHOLESKY, MAT_FACTOR_ICC, MAT_FACTOR_ILU, 

3489:    Output Parameter:
3490: .    flg - PETSC_TRUE if the factorization is available

3492:    Notes:
3493:       Some PETSc matrix formats have alternative solvers available that are contained in alternative packages
3494:      such as pastix, superlu, mumps, spooles etc. 

3496:       PETSc must have been config/configure.py to use the external solver, using the option --download-package

3498:    Level: intermediate

3500: .seealso: MatCopy(), MatDuplicate(), MatGetFactor()
3501: @*/
3502: PetscErrorCode  MatGetFactorAvailable(Mat mat, const MatSolverPackage type,MatFactorType ftype,PetscTruth *flg)
3503: {
3504:   PetscErrorCode         ierr;
3505:   char                   convname[256];
3506:   PetscErrorCode         (*conv)(Mat,MatFactorType,PetscTruth*);


3512:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3513:   MatPreallocated(mat);

3515:   PetscStrcpy(convname,"MatGetFactorAvailable_");
3516:   PetscStrcat(convname,((PetscObject)mat)->type_name);
3517:   PetscStrcat(convname,"_");
3518:   PetscStrcat(convname,type);
3519:   PetscStrcat(convname,"_C");
3520:   PetscObjectQueryFunction((PetscObject)mat,convname,(void (**)(void))&conv);
3521:   if (!conv) {
3522:     *flg = PETSC_FALSE;
3523:   } else {
3524:     (*conv)(mat,ftype,flg);
3525:   }
3526:   return(0);
3527: }


3532: /*@
3533:    MatDuplicate - Duplicates a matrix including the non-zero structure.

3535:    Collective on Mat

3537:    Input Parameters:
3538: +  mat - the matrix
3539: -  op - either MAT_DO_NOT_COPY_VALUES or MAT_COPY_VALUES, cause it to copy nonzero
3540:         values as well or not

3542:    Output Parameter:
3543: .  M - pointer to place new matrix

3545:    Level: intermediate

3547:    Concepts: matrices^duplicating

3549: .seealso: MatCopy(), MatConvert()
3550: @*/
3551: PetscErrorCode  MatDuplicate(Mat mat,MatDuplicateOption op,Mat *M)
3552: {
3554:   Mat            B;
3555:   PetscInt       i;

3561:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3562:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3563:   MatPreallocated(mat);

3565:   *M  = 0;
3566:   if (!mat->ops->duplicate) {
3567:     SETERRQ(PETSC_ERR_SUP,"Not written for this matrix type");
3568:   }
3569:   PetscLogEventBegin(MAT_Convert,mat,0,0,0);
3570:   (*mat->ops->duplicate)(mat,op,M);
3571:   B = *M;
3572:   if (mat->mapping) {
3573:     MatSetLocalToGlobalMapping(B,mat->mapping);
3574:   }
3575:   if (mat->bmapping) {
3576:     MatSetLocalToGlobalMappingBlock(B,mat->bmapping);
3577:   }
3578:   PetscMapCopy(((PetscObject)mat)->comm,mat->rmap,B->rmap);
3579:   PetscMapCopy(((PetscObject)mat)->comm,mat->cmap,B->cmap);
3580: 
3581:   B->stencil.dim = mat->stencil.dim;
3582:   B->stencil.noc = mat->stencil.noc;
3583:   for (i=0; i<=mat->stencil.dim; i++) {
3584:     B->stencil.dims[i]   = mat->stencil.dims[i];
3585:     B->stencil.starts[i] = mat->stencil.starts[i];
3586:   }

3588:   PetscLogEventEnd(MAT_Convert,mat,0,0,0);
3589:   PetscObjectStateIncrease((PetscObject)B);
3590:   return(0);
3591: }

3595: /*@ 
3596:    MatGetDiagonal - Gets the diagonal of a matrix.

3598:    Collective on Mat and Vec

3600:    Input Parameters:
3601: +  mat - the matrix
3602: -  v - the vector for storing the diagonal

3604:    Output Parameter:
3605: .  v - the diagonal of the matrix

3607:    Level: intermediate

3609:    Concepts: matrices^accessing diagonals

3611: .seealso: MatGetRow(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMaxAbs()
3612: @*/
3613: PetscErrorCode  MatGetDiagonal(Mat mat,Vec v)
3614: {

3621:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3622:   if (!mat->ops->getdiagonal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3623:   MatPreallocated(mat);

3625:   (*mat->ops->getdiagonal)(mat,v);
3626:   PetscObjectStateIncrease((PetscObject)v);
3627:   return(0);
3628: }

3632: /*@ 
3633:    MatGetRowMin - Gets the minimum value (of the real part) of each
3634:         row of the matrix

3636:    Collective on Mat and Vec

3638:    Input Parameters:
3639: .  mat - the matrix

3641:    Output Parameter:
3642: +  v - the vector for storing the maximums
3643: -  idx - the indices of the column found for each row (optional)

3645:    Level: intermediate

3647:    Notes: The result of this call are the same as if one converted the matrix to dense format
3648:       and found the minimum value in each row (i.e. the implicit zeros are counted as zeros).

3650:     This code is only implemented for a couple of matrix formats.

3652:    Concepts: matrices^getting row maximums

3654: .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMaxAbs(),
3655:           MatGetRowMax()
3656: @*/
3657: PetscErrorCode  MatGetRowMin(Mat mat,Vec v,PetscInt idx[])
3658: {

3665:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3666:   if (!mat->ops->getrowmax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3667:   MatPreallocated(mat);

3669:   (*mat->ops->getrowmin)(mat,v,idx);
3670:   PetscObjectStateIncrease((PetscObject)v);
3671:   return(0);
3672: }

3676: /*@ 
3677:    MatGetRowMinAbs - Gets the minimum value (in absolute value) of each
3678:         row of the matrix

3680:    Collective on Mat and Vec

3682:    Input Parameters:
3683: .  mat - the matrix

3685:    Output Parameter:
3686: +  v - the vector for storing the minimums
3687: -  idx - the indices of the column found for each row (optional)

3689:    Level: intermediate

3691:    Notes: if a row is completely empty or has only 0.0 values then the idx[] value for that
3692:     row is 0 (the first column).

3694:     This code is only implemented for a couple of matrix formats.

3696:    Concepts: matrices^getting row maximums

3698: .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMax(), MatGetRowMaxAbs(), MatGetRowMin()
3699: @*/
3700: PetscErrorCode  MatGetRowMinAbs(Mat mat,Vec v,PetscInt idx[])
3701: {

3708:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3709:   if (!mat->ops->getrowminabs) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3710:   MatPreallocated(mat);
3711:   if (idx) {PetscMemzero(idx,mat->rmap->n*sizeof(PetscInt));}

3713:   (*mat->ops->getrowminabs)(mat,v,idx);
3714:   PetscObjectStateIncrease((PetscObject)v);
3715:   return(0);
3716: }

3720: /*@ 
3721:    MatGetRowMax - Gets the maximum value (of the real part) of each
3722:         row of the matrix

3724:    Collective on Mat and Vec

3726:    Input Parameters:
3727: .  mat - the matrix

3729:    Output Parameter:
3730: +  v - the vector for storing the maximums
3731: -  idx - the indices of the column found for each row (optional)

3733:    Level: intermediate

3735:    Notes: The result of this call are the same as if one converted the matrix to dense format
3736:       and found the minimum value in each row (i.e. the implicit zeros are counted as zeros).

3738:     This code is only implemented for a couple of matrix formats.

3740:    Concepts: matrices^getting row maximums

3742: .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMaxAbs(), MatGetRowMin()
3743: @*/
3744: PetscErrorCode  MatGetRowMax(Mat mat,Vec v,PetscInt idx[])
3745: {

3752:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3753:   if (!mat->ops->getrowmax) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3754:   MatPreallocated(mat);

3756:   (*mat->ops->getrowmax)(mat,v,idx);
3757:   PetscObjectStateIncrease((PetscObject)v);
3758:   return(0);
3759: }

3763: /*@ 
3764:    MatGetRowMaxAbs - Gets the maximum value (in absolute value) of each
3765:         row of the matrix

3767:    Collective on Mat and Vec

3769:    Input Parameters:
3770: .  mat - the matrix

3772:    Output Parameter:
3773: +  v - the vector for storing the maximums
3774: -  idx - the indices of the column found for each row (optional)

3776:    Level: intermediate

3778:    Notes: if a row is completely empty or has only 0.0 values then the idx[] value for that
3779:     row is 0 (the first column).

3781:     This code is only implemented for a couple of matrix formats.

3783:    Concepts: matrices^getting row maximums

3785: .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMax(), MatGetRowMin()
3786: @*/
3787: PetscErrorCode  MatGetRowMaxAbs(Mat mat,Vec v,PetscInt idx[])
3788: {

3795:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3796:   if (!mat->ops->getrowmaxabs) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3797:   MatPreallocated(mat);
3798:   if (idx) {PetscMemzero(idx,mat->rmap->n*sizeof(PetscInt));}

3800:   (*mat->ops->getrowmaxabs)(mat,v,idx);
3801:   PetscObjectStateIncrease((PetscObject)v);
3802:   return(0);
3803: }

3807: /*@ 
3808:    MatGetRowSum - Gets the sum of each row of the matrix

3810:    Collective on Mat and Vec

3812:    Input Parameters:
3813: .  mat - the matrix

3815:    Output Parameter:
3816: .  v - the vector for storing the maximums

3818:    Level: intermediate

3820:    Notes: This code is slow since it is not currently specialized for different formats

3822:    Concepts: matrices^getting row sums

3824: .seealso: MatGetDiagonal(), MatGetSubMatrices(), MatGetSubmatrix(), MatGetRowMax(), MatGetRowMin()
3825: @*/
3826: PetscErrorCode  MatGetRowSum(Mat mat, Vec v)
3827: {
3828:   PetscInt       start, end, row;
3829:   PetscScalar   *array;

3836:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3837:   MatPreallocated(mat);
3838:   MatGetOwnershipRange(mat, &start, &end);
3839:   VecGetArray(v, &array);
3840:   for(row = start; row < end; ++row) {
3841:     PetscInt           ncols, col;
3842:     const PetscInt    *cols;
3843:     const PetscScalar *vals;

3845:     array[row - start] = 0.0;
3846:     MatGetRow(mat, row, &ncols, &cols, &vals);
3847:     for(col = 0; col < ncols; col++) {
3848:       array[row - start] += vals[col];
3849:     }
3850:     MatRestoreRow(mat, row, &ncols, &cols, &vals);
3851:   }
3852:   VecRestoreArray(v, &array);
3853:   PetscObjectStateIncrease((PetscObject) v);
3854:   return(0);
3855: }

3859: /*@
3860:    MatTranspose - Computes an in-place or out-of-place transpose of a matrix.

3862:    Collective on Mat

3864:    Input Parameter:
3865: +  mat - the matrix to transpose
3866: -  reuse - store the transpose matrix in the provided B

3868:    Output Parameters:
3869: .  B - the transpose 

3871:    Notes:
3872:      If you  pass in &mat for B the transpose will be done in place

3874:    Level: intermediate

3876:    Concepts: matrices^transposing

3878: .seealso: MatMultTranspose(), MatMultTransposeAdd(), MatIsTranspose()
3879: @*/
3880: PetscErrorCode  MatTranspose(Mat mat,MatReuse reuse,Mat *B)
3881: {

3887:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
3888:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
3889:   if (!mat->ops->transpose) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
3890:   MatPreallocated(mat);

3892:   PetscLogEventBegin(MAT_Transpose,mat,0,0,0);
3893:   (*mat->ops->transpose)(mat,reuse,B);
3894:   PetscLogEventEnd(MAT_Transpose,mat,0,0,0);
3895:   if (B) {PetscObjectStateIncrease((PetscObject)*B);}
3896:   return(0);
3897: }

3901: /*@
3902:    MatIsTranspose - Test whether a matrix is another one's transpose, 
3903:         or its own, in which case it tests symmetry.

3905:    Collective on Mat

3907:    Input Parameter:
3908: +  A - the matrix to test
3909: -  B - the matrix to test against, this can equal the first parameter

3911:    Output Parameters:
3912: .  flg - the result

3914:    Notes:
3915:    Only available for SeqAIJ/MPIAIJ matrices. The sequential algorithm
3916:    has a running time of the order of the number of nonzeros; the parallel
3917:    test involves parallel copies of the block-offdiagonal parts of the matrix.

3919:    Level: intermediate

3921:    Concepts: matrices^transposing, matrix^symmetry

3923: .seealso: MatTranspose(), MatIsSymmetric(), MatIsHermitian()
3924: @*/
3925: PetscErrorCode  MatIsTranspose(Mat A,Mat B,PetscReal tol,PetscTruth *flg)
3926: {
3927:   PetscErrorCode ierr,(*f)(Mat,Mat,PetscReal,PetscTruth*),(*g)(Mat,Mat,PetscReal,PetscTruth*);

3933:   PetscObjectQueryFunction((PetscObject)A,"MatIsTranspose_C",(void (**)(void))&f);
3934:   PetscObjectQueryFunction((PetscObject)B,"MatIsTranspose_C",(void (**)(void))&g);
3935:   if (f && g) {
3936:     if (f==g) {
3937:       (*f)(A,B,tol,flg);
3938:     } else {
3939:       SETERRQ(PETSC_ERR_ARG_NOTSAMETYPE,"Matrices do not have the same comparator for symmetry test");
3940:     }
3941:   }
3942:   return(0);
3943: }

3947: /*@
3948:    MatIsHermitianTranspose - Test whether a matrix is another one's Hermitian transpose, 

3950:    Collective on Mat

3952:    Input Parameter:
3953: +  A - the matrix to test
3954: -  B - the matrix to test against, this can equal the first parameter

3956:    Output Parameters:
3957: .  flg - the result

3959:    Notes:
3960:    Only available for SeqAIJ/MPIAIJ matrices. The sequential algorithm
3961:    has a running time of the order of the number of nonzeros; the parallel
3962:    test involves parallel copies of the block-offdiagonal parts of the matrix.

3964:    Level: intermediate

3966:    Concepts: matrices^transposing, matrix^symmetry

3968: .seealso: MatTranspose(), MatIsSymmetric(), MatIsHermitian(), MatIsTranspose()
3969: @*/
3970: PetscErrorCode  MatIsHermitianTranspose(Mat A,Mat B,PetscReal tol,PetscTruth *flg)
3971: {
3972:   PetscErrorCode ierr,(*f)(Mat,Mat,PetscReal,PetscTruth*),(*g)(Mat,Mat,PetscReal,PetscTruth*);

3978:   PetscObjectQueryFunction((PetscObject)A,"MatIsHermitianTranspose_C",(void (**)(void))&f);
3979:   PetscObjectQueryFunction((PetscObject)B,"MatIsHermitianTranspose_C",(void (**)(void))&g);
3980:   if (f && g) {
3981:     if (f==g) {
3982:       (*f)(A,B,tol,flg);
3983:     } else {
3984:       SETERRQ(PETSC_ERR_ARG_NOTSAMETYPE,"Matrices do not have the same comparator for Hermitian test");
3985:     }
3986:   }
3987:   return(0);
3988: }

3992: /*@
3993:    MatPermute - Creates a new matrix with rows and columns permuted from the 
3994:    original.

3996:    Collective on Mat

3998:    Input Parameters:
3999: +  mat - the matrix to permute
4000: .  row - row permutation, each processor supplies only the permutation for its rows
4001: -  col - column permutation, each processor needs the entire column permutation, that is
4002:          this is the same size as the total number of columns in the matrix

4004:    Output Parameters:
4005: .  B - the permuted matrix

4007:    Level: advanced

4009:    Concepts: matrices^permuting

4011: .seealso: MatGetOrdering()
4012: @*/
4013: PetscErrorCode  MatPermute(Mat mat,IS row,IS col,Mat *B)
4014: {

4023:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4024:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4025:   if (!mat->ops->permute) SETERRQ1(PETSC_ERR_SUP,"MatPermute not available for Mat type %s",((PetscObject)mat)->type_name);
4026:   MatPreallocated(mat);

4028:   (*mat->ops->permute)(mat,row,col,B);
4029:   PetscObjectStateIncrease((PetscObject)*B);
4030:   return(0);
4031: }

4035: /*@
4036:   MatPermuteSparsify - Creates a new matrix with rows and columns permuted from the 
4037:   original and sparsified to the prescribed tolerance.

4039:   Collective on Mat

4041:   Input Parameters:
4042: + A    - The matrix to permute
4043: . band - The half-bandwidth of the sparsified matrix, or PETSC_DECIDE
4044: . frac - The half-bandwidth as a fraction of the total size, or 0.0
4045: . tol  - The drop tolerance
4046: . rowp - The row permutation
4047: - colp - The column permutation

4049:   Output Parameter:
4050: . B    - The permuted, sparsified matrix

4052:   Level: advanced

4054:   Note:
4055:   The default behavior (band = PETSC_DECIDE and frac = 0.0) is to
4056:   restrict the half-bandwidth of the resulting matrix to 5% of the
4057:   total matrix size.

4059: .keywords: matrix, permute, sparsify

4061: .seealso: MatGetOrdering(), MatPermute()
4062: @*/
4063: PetscErrorCode  MatPermuteSparsify(Mat A, PetscInt band, PetscReal frac, PetscReal tol, IS rowp, IS colp, Mat *B)
4064: {
4065:   IS                irowp, icolp;
4066:   const PetscInt    *rows, *cols;
4067:   PetscInt          M, N, locRowStart, locRowEnd;
4068:   PetscInt          nz, newNz;
4069:   const PetscInt    *cwork;
4070:   PetscInt          *cnew;
4071:   const PetscScalar *vwork;
4072:   PetscScalar       *vnew;
4073:   PetscInt          bw, issize;
4074:   PetscInt          row, locRow, newRow, col, newCol;
4075:   PetscErrorCode    ierr;

4082:   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE, "Not for unassembled matrix");
4083:   if (A->factor)     SETERRQ(PETSC_ERR_ARG_WRONGSTATE, "Not for factored matrix");
4084:   if (!A->ops->permutesparsify) {
4085:     MatGetSize(A, &M, &N);
4086:     MatGetOwnershipRange(A, &locRowStart, &locRowEnd);
4087:     ISGetSize(rowp, &issize);
4088:     if (issize != M) SETERRQ2(PETSC_ERR_ARG_WRONG, "Wrong size %D for row permutation, should be %D", issize, M);
4089:     ISGetSize(colp, &issize);
4090:     if (issize != N) SETERRQ2(PETSC_ERR_ARG_WRONG, "Wrong size %D for column permutation, should be %D", issize, N);
4091:     ISInvertPermutation(rowp, 0, &irowp);
4092:     ISGetIndices(irowp, &rows);
4093:     ISInvertPermutation(colp, 0, &icolp);
4094:     ISGetIndices(icolp, &cols);
4095:     PetscMalloc(N * sizeof(PetscInt),         &cnew);
4096:     PetscMalloc(N * sizeof(PetscScalar), &vnew);

4098:     /* Setup bandwidth to include */
4099:     if (band == PETSC_DECIDE) {
4100:       if (frac <= 0.0)
4101:         bw = (PetscInt) (M * 0.05);
4102:       else
4103:         bw = (PetscInt) (M * frac);
4104:     } else {
4105:       if (band <= 0) SETERRQ(PETSC_ERR_ARG_WRONG, "Bandwidth must be a positive integer");
4106:       bw = band;
4107:     }

4109:     /* Put values into new matrix */
4110:     MatDuplicate(A, MAT_DO_NOT_COPY_VALUES, B);
4111:     for(row = locRowStart, locRow = 0; row < locRowEnd; row++, locRow++) {
4112:       MatGetRow(A, row, &nz, &cwork, &vwork);
4113:       newRow   = rows[locRow]+locRowStart;
4114:       for(col = 0, newNz = 0; col < nz; col++) {
4115:         newCol = cols[cwork[col]];
4116:         if ((newCol >= newRow - bw) && (newCol < newRow + bw) && (PetscAbsScalar(vwork[col]) >= tol)) {
4117:           cnew[newNz] = newCol;
4118:           vnew[newNz] = vwork[col];
4119:           newNz++;
4120:         }
4121:       }
4122:       MatSetValues(*B, 1, &newRow, newNz, cnew, vnew, INSERT_VALUES);
4123:       MatRestoreRow(A, row, &nz, &cwork, &vwork);
4124:     }
4125:     PetscFree(cnew);
4126:     PetscFree(vnew);
4127:     MatAssemblyBegin(*B, MAT_FINAL_ASSEMBLY);
4128:     MatAssemblyEnd(*B, MAT_FINAL_ASSEMBLY);
4129:     ISRestoreIndices(irowp, &rows);
4130:     ISRestoreIndices(icolp, &cols);
4131:     ISDestroy(irowp);
4132:     ISDestroy(icolp);
4133:   } else {
4134:     (*A->ops->permutesparsify)(A, band, frac, tol, rowp, colp, B);
4135:   }
4136:   PetscObjectStateIncrease((PetscObject)*B);
4137:   return(0);
4138: }

4142: /*@
4143:    MatEqual - Compares two matrices.

4145:    Collective on Mat

4147:    Input Parameters:
4148: +  A - the first matrix
4149: -  B - the second matrix

4151:    Output Parameter:
4152: .  flg - PETSC_TRUE if the matrices are equal; PETSC_FALSE otherwise.

4154:    Level: intermediate

4156:    Concepts: matrices^equality between
4157: @*/
4158: PetscErrorCode  MatEqual(Mat A,Mat B,PetscTruth *flg)
4159: {

4169:   MatPreallocated(B);
4170:   if (!A->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4171:   if (!B->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4172:   if (A->rmap->N != B->rmap->N || A->cmap->N != B->cmap->N) SETERRQ4(PETSC_ERR_ARG_SIZ,"Mat A,Mat B: global dim %D %D %D %D",A->rmap->N,B->rmap->N,A->cmap->N,B->cmap->N);
4173:   if (!A->ops->equal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)A)->type_name);
4174:   if (!B->ops->equal) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)B)->type_name);
4175:   if (A->ops->equal != B->ops->equal) SETERRQ2(PETSC_ERR_ARG_INCOMP,"A is type: %s\nB is type: %s",((PetscObject)A)->type_name,((PetscObject)B)->type_name);
4176:   MatPreallocated(A);

4178:   (*A->ops->equal)(A,B,flg);
4179:   return(0);
4180: }

4184: /*@
4185:    MatDiagonalScale - Scales a matrix on the left and right by diagonal
4186:    matrices that are stored as vectors.  Either of the two scaling
4187:    matrices can be PETSC_NULL.

4189:    Collective on Mat

4191:    Input Parameters:
4192: +  mat - the matrix to be scaled
4193: .  l - the left scaling vector (or PETSC_NULL)
4194: -  r - the right scaling vector (or PETSC_NULL)

4196:    Notes:
4197:    MatDiagonalScale() computes A = LAR, where
4198:    L = a diagonal matrix (stored as a vector), R = a diagonal matrix (stored as a vector)

4200:    Level: intermediate

4202:    Concepts: matrices^diagonal scaling
4203:    Concepts: diagonal scaling of matrices

4205: .seealso: MatScale()
4206: @*/
4207: PetscErrorCode  MatDiagonalScale(Mat mat,Vec l,Vec r)
4208: {

4214:   if (!mat->ops->diagonalscale) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4217:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4218:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4219:   MatPreallocated(mat);

4221:   PetscLogEventBegin(MAT_Scale,mat,0,0,0);
4222:   (*mat->ops->diagonalscale)(mat,l,r);
4223:   PetscLogEventEnd(MAT_Scale,mat,0,0,0);
4224:   PetscObjectStateIncrease((PetscObject)mat);
4225:   return(0);
4226: }

4230: /*@
4231:     MatScale - Scales all elements of a matrix by a given number.

4233:     Collective on Mat

4235:     Input Parameters:
4236: +   mat - the matrix to be scaled
4237: -   a  - the scaling value

4239:     Output Parameter:
4240: .   mat - the scaled matrix

4242:     Level: intermediate

4244:     Concepts: matrices^scaling all entries

4246: .seealso: MatDiagonalScale()
4247: @*/
4248: PetscErrorCode  MatScale(Mat mat,PetscScalar a)
4249: {

4255:   if (a != 1.0 && !mat->ops->scale) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4256:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4257:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4258:   MatPreallocated(mat);

4260:   PetscLogEventBegin(MAT_Scale,mat,0,0,0);
4261:   if (a != 1.0) {
4262:     (*mat->ops->scale)(mat,a);
4263:     PetscObjectStateIncrease((PetscObject)mat);
4264:   }
4265:   PetscLogEventEnd(MAT_Scale,mat,0,0,0);
4266:   return(0);
4267: }

4271: /*@ 
4272:    MatNorm - Calculates various norms of a matrix.

4274:    Collective on Mat

4276:    Input Parameters:
4277: +  mat - the matrix
4278: -  type - the type of norm, NORM_1, NORM_FROBENIUS, NORM_INFINITY

4280:    Output Parameters:
4281: .  nrm - the resulting norm 

4283:    Level: intermediate

4285:    Concepts: matrices^norm
4286:    Concepts: norm^of matrix
4287: @*/
4288: PetscErrorCode  MatNorm(Mat mat,NormType type,PetscReal *nrm)
4289: {


4297:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4298:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4299:   if (!mat->ops->norm) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4300:   MatPreallocated(mat);

4302:   (*mat->ops->norm)(mat,type,nrm);
4303:   return(0);
4304: }

4306: /* 
4307:      This variable is used to prevent counting of MatAssemblyBegin() that
4308:    are called from within a MatAssemblyEnd().
4309: */
4310: static PetscInt MatAssemblyEnd_InUse = 0;
4313: /*@
4314:    MatAssemblyBegin - Begins assembling the matrix.  This routine should
4315:    be called after completing all calls to MatSetValues().

4317:    Collective on Mat

4319:    Input Parameters:
4320: +  mat - the matrix 
4321: -  type - type of assembly, either MAT_FLUSH_ASSEMBLY or MAT_FINAL_ASSEMBLY
4322:  
4323:    Notes: 
4324:    MatSetValues() generally caches the values.  The matrix is ready to
4325:    use only after MatAssemblyBegin() and MatAssemblyEnd() have been called.
4326:    Use MAT_FLUSH_ASSEMBLY when switching between ADD_VALUES and INSERT_VALUES
4327:    in MatSetValues(); use MAT_FINAL_ASSEMBLY for the final assembly before
4328:    using the matrix.

4330:    Level: beginner

4332:    Concepts: matrices^assembling

4334: .seealso: MatAssemblyEnd(), MatSetValues(), MatAssembled()
4335: @*/
4336: PetscErrorCode  MatAssemblyBegin(Mat mat,MatAssemblyType type)
4337: {

4343:   MatPreallocated(mat);
4344:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix.\nDid you forget to call MatSetUnfactored()?");
4345:   if (mat->assembled) {
4346:     mat->was_assembled = PETSC_TRUE;
4347:     mat->assembled     = PETSC_FALSE;
4348:   }
4349:   if (!MatAssemblyEnd_InUse) {
4350:     PetscLogEventBegin(MAT_AssemblyBegin,mat,0,0,0);
4351:     if (mat->ops->assemblybegin){(*mat->ops->assemblybegin)(mat,type);}
4352:     PetscLogEventEnd(MAT_AssemblyBegin,mat,0,0,0);
4353:   } else {
4354:     if (mat->ops->assemblybegin){(*mat->ops->assemblybegin)(mat,type);}
4355:   }
4356:   return(0);
4357: }

4361: /*@
4362:    MatAssembled - Indicates if a matrix has been assembled and is ready for
4363:      use; for example, in matrix-vector product.

4365:    Collective on Mat

4367:    Input Parameter:
4368: .  mat - the matrix 

4370:    Output Parameter:
4371: .  assembled - PETSC_TRUE or PETSC_FALSE

4373:    Level: advanced

4375:    Concepts: matrices^assembled?

4377: .seealso: MatAssemblyEnd(), MatSetValues(), MatAssemblyBegin()
4378: @*/
4379: PetscErrorCode  MatAssembled(Mat mat,PetscTruth *assembled)
4380: {
4385:   *assembled = mat->assembled;
4386:   return(0);
4387: }

4391: /*
4392:     Processes command line options to determine if/how a matrix
4393:   is to be viewed. Called by MatAssemblyEnd() and MatLoad().
4394: */
4395: PetscErrorCode MatView_Private(Mat mat)
4396: {
4397:   PetscErrorCode    ierr;
4398:   PetscTruth        flg1,flg2,flg3,flg4,flg6,flg7,flg8;
4399:   static PetscTruth incall = PETSC_FALSE;
4400: #if defined(PETSC_USE_SOCKET_VIEWER)
4401:   PetscTruth        flg5;
4402: #endif

4405:   if (incall) return(0);
4406:   incall = PETSC_TRUE;
4407:   PetscOptionsBegin(((PetscObject)mat)->comm,((PetscObject)mat)->prefix,"Matrix Options","Mat");
4408:     PetscOptionsName("-mat_view_info","Information on matrix size","MatView",&flg1);
4409:     PetscOptionsName("-mat_view_info_detailed","Nonzeros in the matrix","MatView",&flg2);
4410:     PetscOptionsName("-mat_view","Print matrix to stdout","MatView",&flg3);
4411:     PetscOptionsName("-mat_view_matlab","Print matrix to stdout in a format Matlab can read","MatView",&flg4);
4412: #if defined(PETSC_USE_SOCKET_VIEWER)
4413:     PetscOptionsName("-mat_view_socket","Send matrix to socket (can be read from matlab)","MatView",&flg5);
4414: #endif
4415:     PetscOptionsName("-mat_view_binary","Save matrix to file in binary format","MatView",&flg6);
4416:     PetscOptionsName("-mat_view_draw","Draw the matrix nonzero structure","MatView",&flg7);
4417:   PetscOptionsEnd();

4419:   if (flg1) {
4420:     PetscViewer viewer;

4422:     PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);
4423:     PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO);
4424:     MatView(mat,viewer);
4425:     PetscViewerPopFormat(viewer);
4426:   }
4427:   if (flg2) {
4428:     PetscViewer viewer;

4430:     PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);
4431:     PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL);
4432:     MatView(mat,viewer);
4433:     PetscViewerPopFormat(viewer);
4434:   }
4435:   if (flg3) {
4436:     PetscViewer viewer;

4438:     PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);
4439:     MatView(mat,viewer);
4440:   }
4441:   if (flg4) {
4442:     PetscViewer viewer;

4444:     PetscViewerASCIIGetStdout(((PetscObject)mat)->comm,&viewer);
4445:     PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB);
4446:     MatView(mat,viewer);
4447:     PetscViewerPopFormat(viewer);
4448:   }
4449: #if defined(PETSC_USE_SOCKET_VIEWER)
4450:   if (flg5) {
4451:     MatView(mat,PETSC_VIEWER_SOCKET_(((PetscObject)mat)->comm));
4452:     PetscViewerFlush(PETSC_VIEWER_SOCKET_(((PetscObject)mat)->comm));
4453:   }
4454: #endif
4455:   if (flg6) {
4456:     MatView(mat,PETSC_VIEWER_BINARY_(((PetscObject)mat)->comm));
4457:     PetscViewerFlush(PETSC_VIEWER_BINARY_(((PetscObject)mat)->comm));
4458:   }
4459:   if (flg7) {
4460:     PetscOptionsHasName(((PetscObject)mat)->prefix,"-mat_view_contour",&flg8);
4461:     if (flg8) {
4462:       PetscViewerPushFormat(PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm),PETSC_VIEWER_DRAW_CONTOUR);
4463:     }
4464:     MatView(mat,PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm));
4465:     PetscViewerFlush(PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm));
4466:     if (flg8) {
4467:       PetscViewerPopFormat(PETSC_VIEWER_DRAW_(((PetscObject)mat)->comm));
4468:     }
4469:   }
4470:   incall = PETSC_FALSE;
4471:   return(0);
4472: }

4476: /*@
4477:    MatAssemblyEnd - Completes assembling the matrix.  This routine should
4478:    be called after MatAssemblyBegin().

4480:    Collective on Mat

4482:    Input Parameters:
4483: +  mat - the matrix 
4484: -  type - type of assembly, either MAT_FLUSH_ASSEMBLY or MAT_FINAL_ASSEMBLY

4486:    Options Database Keys:
4487: +  -mat_view_info - Prints info on matrix at conclusion of MatEndAssembly()
4488: .  -mat_view_info_detailed - Prints more detailed info
4489: .  -mat_view - Prints matrix in ASCII format
4490: .  -mat_view_matlab - Prints matrix in Matlab format
4491: .  -mat_view_draw - PetscDraws nonzero structure of matrix, using MatView() and PetscDrawOpenX().
4492: .  -display <name> - Sets display name (default is host)
4493: .  -draw_pause <sec> - Sets number of seconds to pause after display
4494: .  -mat_view_socket - Sends matrix to socket, can be accessed from Matlab (see users manual)
4495: .  -viewer_socket_machine <machine>
4496: .  -viewer_socket_port <port>
4497: .  -mat_view_binary - save matrix to file in binary format
4498: -  -viewer_binary_filename <name>

4500:    Notes: 
4501:    MatSetValues() generally caches the values.  The matrix is ready to
4502:    use only after MatAssemblyBegin() and MatAssemblyEnd() have been called.
4503:    Use MAT_FLUSH_ASSEMBLY when switching between ADD_VALUES and INSERT_VALUES
4504:    in MatSetValues(); use MAT_FINAL_ASSEMBLY for the final assembly before
4505:    using the matrix.

4507:    Level: beginner

4509: .seealso: MatAssemblyBegin(), MatSetValues(), PetscDrawOpenX(), MatView(), MatAssembled(), PetscViewerSocketOpen()
4510: @*/
4511: PetscErrorCode  MatAssemblyEnd(Mat mat,MatAssemblyType type)
4512: {
4513:   PetscErrorCode  ierr;
4514:   static PetscInt inassm = 0;
4515:   PetscTruth      flg;


4521:   inassm++;
4522:   MatAssemblyEnd_InUse++;
4523:   if (MatAssemblyEnd_InUse == 1) { /* Do the logging only the first time through */
4524:     PetscLogEventBegin(MAT_AssemblyEnd,mat,0,0,0);
4525:     if (mat->ops->assemblyend) {
4526:       (*mat->ops->assemblyend)(mat,type);
4527:     }
4528:     PetscLogEventEnd(MAT_AssemblyEnd,mat,0,0,0);
4529:   } else {
4530:     if (mat->ops->assemblyend) {
4531:       (*mat->ops->assemblyend)(mat,type);
4532:     }
4533:   }

4535:   /* Flush assembly is not a true assembly */
4536:   if (type != MAT_FLUSH_ASSEMBLY) {
4537:     mat->assembled  = PETSC_TRUE; mat->num_ass++;
4538:   }
4539:   mat->insertmode = NOT_SET_VALUES;
4540:   MatAssemblyEnd_InUse--;
4541:   PetscObjectStateIncrease((PetscObject)mat);
4542:   if (!mat->symmetric_eternal) {
4543:     mat->symmetric_set              = PETSC_FALSE;
4544:     mat->hermitian_set              = PETSC_FALSE;
4545:     mat->structurally_symmetric_set = PETSC_FALSE;
4546:   }
4547:   if (inassm == 1 && type != MAT_FLUSH_ASSEMBLY) {
4548:     MatView_Private(mat);
4549:     PetscOptionsHasName(((PetscObject)mat)->prefix,"-mat_is_symmetric",&flg);
4550:     if (flg) {
4551:       PetscReal tol = 0.0;
4552:       PetscOptionsGetReal(((PetscObject)mat)->prefix,"-mat_is_symmetric",&tol,PETSC_NULL);
4553:       MatIsSymmetric(mat,tol,&flg);
4554:       if (flg) {
4555:         PetscPrintf(((PetscObject)mat)->comm,"Matrix is symmetric (tolerance %G)\n",tol);
4556:       } else {
4557:         PetscPrintf(((PetscObject)mat)->comm,"Matrix is not symmetric (tolerance %G)\n",tol);
4558:       }
4559:     }
4560:   }
4561:   inassm--;
4562:   return(0);
4563: }


4568: /*@
4569:    MatCompress - Tries to store the matrix in as little space as 
4570:    possible.  May fail if memory is already fully used, since it
4571:    tries to allocate new space.

4573:    Collective on Mat

4575:    Input Parameters:
4576: .  mat - the matrix 

4578:    Level: advanced

4580: @*/
4581: PetscErrorCode  MatCompress(Mat mat)
4582: {

4588:   MatPreallocated(mat);
4589:   if (mat->ops->compress) {(*mat->ops->compress)(mat);}
4590:   return(0);
4591: }

4595: /*@
4596:    MatSetOption - Sets a parameter option for a matrix. Some options
4597:    may be specific to certain storage formats.  Some options
4598:    determine how values will be inserted (or added). Sorted, 
4599:    row-oriented input will generally assemble the fastest. The default
4600:    is row-oriented, nonsorted input. 

4602:    Collective on Mat

4604:    Input Parameters:
4605: +  mat - the matrix 
4606: .  option - the option, one of those listed below (and possibly others),
4607: -  flg - turn the option on (PETSC_TRUE) or off (PETSC_FALSE)

4609:   Options Describing Matrix Structure:
4610: +    MAT_SYMMETRIC - symmetric in terms of both structure and value
4611: .    MAT_HERMITIAN - transpose is the complex conjugation
4612: .    MAT_STRUCTURALLY_SYMMETRIC - symmetric nonzero structure
4613: -    MAT_SYMMETRY_ETERNAL - if you would like the symmetry/Hermitian flag
4614:                             you set to be kept with all future use of the matrix
4615:                             including after MatAssemblyBegin/End() which could
4616:                             potentially change the symmetry structure, i.e. you 
4617:                             KNOW the matrix will ALWAYS have the property you set.


4620:    Options For Use with MatSetValues():
4621:    Insert a logically dense subblock, which can be
4622: .    MAT_ROW_ORIENTED - row-oriented (default)

4624:    Note these options reflect the data you pass in with MatSetValues(); it has 
4625:    nothing to do with how the data is stored internally in the matrix 
4626:    data structure.

4628:    When (re)assembling a matrix, we can restrict the input for
4629:    efficiency/debugging purposes.  These options include
4630: +    MAT_NEW_NONZERO_LOCATIONS - additional insertions will be
4631:         allowed if they generate a new nonzero
4632: .    MAT_NEW_DIAGONALS - new diagonals will be allowed (for block diagonal format only)
4633: .    MAT_IGNORE_OFF_PROC_ENTRIES - drops off-processor entries
4634: .    MAT_NEW_NONZERO_LOCATION_ERR - generates an error for new matrix entry
4635: -    MAT_USE_HASH_TABLE - uses a hash table to speed up matrix assembly

4637:    Notes:
4638:    Some options are relevant only for particular matrix types and
4639:    are thus ignored by others.  Other options are not supported by
4640:    certain matrix types and will generate an error message if set.

4642:    If using a Fortran 77 module to compute a matrix, one may need to 
4643:    use the column-oriented option (or convert to the row-oriented 
4644:    format).  

4646:    MAT_NEW_NONZERO_LOCATIONS set to PETSC_FALSE indicates that any add or insertion 
4647:    that would generate a new entry in the nonzero structure is instead
4648:    ignored.  Thus, if memory has not alredy been allocated for this particular 
4649:    data, then the insertion is ignored. For dense matrices, in which
4650:    the entire array is allocated, no entries are ever ignored. 
4651:    Set after the first MatAssemblyEnd()

4653:    MAT_NEW_NONZERO_LOCATION_ERR indicates that any add or insertion 
4654:    that would generate a new entry in the nonzero structure instead produces 
4655:    an error. (Currently supported for AIJ and BAIJ formats only.)
4656:    This is a useful flag when using SAME_NONZERO_PATTERN in calling
4657:    KSPSetOperators() to ensure that the nonzero pattern truely does 
4658:    remain unchanged. Set after the first MatAssemblyEnd()

4660:    MAT_NEW_NONZERO_ALLOCATION_ERR indicates that any add or insertion 
4661:    that would generate a new entry that has not been preallocated will 
4662:    instead produce an error. (Currently supported for AIJ and BAIJ formats
4663:    only.) This is a useful flag when debugging matrix memory preallocation.

4665:    MAT_IGNORE_OFF_PROC_ENTRIES indicates entries destined for 
4666:    other processors should be dropped, rather than stashed.
4667:    This is useful if you know that the "owning" processor is also 
4668:    always generating the correct matrix entries, so that PETSc need
4669:    not transfer duplicate entries generated on another processor.
4670:    
4671:    MAT_USE_HASH_TABLE indicates that a hash table be used to improve the
4672:    searches during matrix assembly. When this flag is set, the hash table
4673:    is created during the first Matrix Assembly. This hash table is
4674:    used the next time through, during MatSetVaules()/MatSetVaulesBlocked()
4675:    to improve the searching of indices. MAT_NEW_NONZERO_LOCATIONS flag 
4676:    should be used with MAT_USE_HASH_TABLE flag. This option is currently
4677:    supported by MATMPIBAIJ format only.

4679:    MAT_KEEP_ZEROED_ROWS indicates when MatZeroRows() is called the zeroed entries
4680:    are kept in the nonzero structure

4682:    MAT_IGNORE_ZERO_ENTRIES - for AIJ/IS matrices this will stop zero values from creating
4683:    a zero location in the matrix

4685:    MAT_USE_INODES - indicates using inode version of the code - works with AIJ and 
4686:    ROWBS matrix types

4688:    Level: intermediate

4690:    Concepts: matrices^setting options

4692: @*/
4693: PetscErrorCode  MatSetOption(Mat mat,MatOption op,PetscTruth flg)
4694: {

4700:   if (((int) op) < 0 || ((int) op) >= NUM_MAT_OPTIONS) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Options %d is out of range",(int)op);
4701:   MatPreallocated(mat);
4702:   switch (op) {
4703:   case MAT_SYMMETRIC:
4704:     mat->symmetric                  = flg;
4705:     if (flg) mat->structurally_symmetric     = PETSC_TRUE;
4706:     mat->symmetric_set              = PETSC_TRUE;
4707:     mat->structurally_symmetric_set = flg;
4708:     break;
4709:   case MAT_HERMITIAN:
4710:     mat->hermitian                  = flg;
4711:     if (flg) mat->structurally_symmetric     = PETSC_TRUE;
4712:     mat->hermitian_set              = PETSC_TRUE;
4713:     mat->structurally_symmetric_set = flg;
4714:     break;
4715:   case MAT_STRUCTURALLY_SYMMETRIC:
4716:     mat->structurally_symmetric     = flg;
4717:     mat->structurally_symmetric_set = PETSC_TRUE;
4718:     break;
4719:   case MAT_SYMMETRY_ETERNAL:
4720:     mat->symmetric_eternal          = flg;
4721:     break;
4722:   default:
4723:     break;
4724:   }
4725:   if (mat->ops->setoption) {
4726:     (*mat->ops->setoption)(mat,op,flg);
4727:   }
4728:   return(0);
4729: }

4733: /*@
4734:    MatZeroEntries - Zeros all entries of a matrix.  For sparse matrices
4735:    this routine retains the old nonzero structure.

4737:    Collective on Mat

4739:    Input Parameters:
4740: .  mat - the matrix 

4742:    Level: intermediate

4744:    Concepts: matrices^zeroing

4746: .seealso: MatZeroRows()
4747: @*/
4748: PetscErrorCode  MatZeroEntries(Mat mat)
4749: {

4755:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4756:   if (mat->insertmode != NOT_SET_VALUES) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for matrices where you have set values but not yet assembled");
4757:   if (!mat->ops->zeroentries) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4758:   MatPreallocated(mat);

4760:   PetscLogEventBegin(MAT_ZeroEntries,mat,0,0,0);
4761:   (*mat->ops->zeroentries)(mat);
4762:   PetscLogEventEnd(MAT_ZeroEntries,mat,0,0,0);
4763:   PetscObjectStateIncrease((PetscObject)mat);
4764:   return(0);
4765: }

4769: /*@C
4770:    MatZeroRows - Zeros all entries (except possibly the main diagonal)
4771:    of a set of rows of a matrix.

4773:    Collective on Mat

4775:    Input Parameters:
4776: +  mat - the matrix
4777: .  numRows - the number of rows to remove
4778: .  rows - the global row indices
4779: -  diag - value put in all diagonals of eliminated rows (0.0 will even eliminate diagonal entry)

4781:    Notes:
4782:    For the AIJ and BAIJ matrix formats this removes the old nonzero structure,
4783:    but does not release memory.  For the dense and block diagonal
4784:    formats this does not alter the nonzero structure.

4786:    If the option MatSetOption(mat,MAT_KEEP_ZEROED_ROWS,PETSC_TRUE) the nonzero structure
4787:    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4788:    merely zeroed.

4790:    The user can set a value in the diagonal entry (or for the AIJ and
4791:    row formats can optionally remove the main diagonal entry from the
4792:    nonzero structure as well, by passing 0.0 as the final argument).

4794:    For the parallel case, all processes that share the matrix (i.e.,
4795:    those in the communicator used for matrix creation) MUST call this
4796:    routine, regardless of whether any rows being zeroed are owned by
4797:    them.

4799:    Each processor can indicate any rows in the entire matrix to be zeroed (i.e. each process does NOT have to
4800:    list only rows local to itself).

4802:    Level: intermediate

4804:    Concepts: matrices^zeroing rows

4806: .seealso: MatZeroRowsIS(), MatZeroEntries(), MatZeroRowsLocal(), MatSetOption()
4807: @*/
4808: PetscErrorCode  MatZeroRows(Mat mat,PetscInt numRows,const PetscInt rows[],PetscScalar diag)
4809: {

4816:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4817:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4818:   if (!mat->ops->zerorows) SETERRQ1(PETSC_ERR_SUP,"Mat type %s",((PetscObject)mat)->type_name);
4819:   MatPreallocated(mat);

4821:   (*mat->ops->zerorows)(mat,numRows,rows,diag);
4822:   MatView_Private(mat);
4823:   PetscObjectStateIncrease((PetscObject)mat);
4824:   return(0);
4825: }

4829: /*@C
4830:    MatZeroRowsIS - Zeros all entries (except possibly the main diagonal)
4831:    of a set of rows of a matrix.

4833:    Collective on Mat

4835:    Input Parameters:
4836: +  mat - the matrix
4837: .  is - index set of rows to remove
4838: -  diag - value put in all diagonals of eliminated rows

4840:    Notes:
4841:    For the AIJ and BAIJ matrix formats this removes the old nonzero structure,
4842:    but does not release memory.  For the dense and block diagonal
4843:    formats this does not alter the nonzero structure.

4845:    If the option MatSetOption(mat,MAT_KEEP_ZEROED_ROWS,PETSC_TRUE) the nonzero structure
4846:    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4847:    merely zeroed.

4849:    The user can set a value in the diagonal entry (or for the AIJ and
4850:    row formats can optionally remove the main diagonal entry from the
4851:    nonzero structure as well, by passing 0.0 as the final argument).

4853:    For the parallel case, all processes that share the matrix (i.e.,
4854:    those in the communicator used for matrix creation) MUST call this
4855:    routine, regardless of whether any rows being zeroed are owned by
4856:    them.

4858:    Each processor should list the rows that IT wants zeroed

4860:    Level: intermediate

4862:    Concepts: matrices^zeroing rows

4864: .seealso: MatZeroRows(), MatZeroEntries(), MatZeroRowsLocal(), MatSetOption()
4865: @*/
4866: PetscErrorCode  MatZeroRowsIS(Mat mat,IS is,PetscScalar diag)
4867: {
4868:   PetscInt       numRows;
4869:   const PetscInt *rows;

4876:   ISGetLocalSize(is,&numRows);
4877:   ISGetIndices(is,&rows);
4878:   MatZeroRows(mat,numRows,rows,diag);
4879:   ISRestoreIndices(is,&rows);
4880:   return(0);
4881: }

4885: /*@C 
4886:    MatZeroRowsLocal - Zeros all entries (except possibly the main diagonal)
4887:    of a set of rows of a matrix; using local numbering of rows.

4889:    Collective on Mat

4891:    Input Parameters:
4892: +  mat - the matrix
4893: .  numRows - the number of rows to remove
4894: .  rows - the global row indices
4895: -  diag - value put in all diagonals of eliminated rows

4897:    Notes:
4898:    Before calling MatZeroRowsLocal(), the user must first set the
4899:    local-to-global mapping by calling MatSetLocalToGlobalMapping().

4901:    For the AIJ matrix formats this removes the old nonzero structure,
4902:    but does not release memory.  For the dense and block diagonal
4903:    formats this does not alter the nonzero structure.

4905:    If the option MatSetOption(mat,MAT_KEEP_ZEROED_ROWS,PETSC_TRUE) the nonzero structure
4906:    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4907:    merely zeroed.

4909:    The user can set a value in the diagonal entry (or for the AIJ and
4910:    row formats can optionally remove the main diagonal entry from the
4911:    nonzero structure as well, by passing 0.0 as the final argument).

4913:    Level: intermediate

4915:    Concepts: matrices^zeroing

4917: .seealso: MatZeroRows(), MatZeroRowsLocalIS(), MatZeroEntries(), MatZeroRows(), MatSetLocalToGlobalMapping
4918: @*/
4919: PetscErrorCode  MatZeroRowsLocal(Mat mat,PetscInt numRows,const PetscInt rows[],PetscScalar diag)
4920: {

4927:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4928:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4929:   MatPreallocated(mat);

4931:   if (mat->ops->zerorowslocal) {
4932:     (*mat->ops->zerorowslocal)(mat,numRows,rows,diag);
4933:   } else {
4934:     IS             is, newis;
4935:     const PetscInt *newRows;

4937:     if (!mat->mapping) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Need to provide local to global mapping to matrix first");
4938:     ISCreateGeneral(PETSC_COMM_SELF,numRows,rows,&is);
4939:     ISLocalToGlobalMappingApplyIS(mat->mapping,is,&newis);
4940:     ISGetIndices(newis,&newRows);
4941:     (*mat->ops->zerorows)(mat,numRows,newRows,diag);
4942:     ISRestoreIndices(newis,&newRows);
4943:     ISDestroy(newis);
4944:     ISDestroy(is);
4945:   }
4946:   PetscObjectStateIncrease((PetscObject)mat);
4947:   return(0);
4948: }

4952: /*@C 
4953:    MatZeroRowsLocalIS - Zeros all entries (except possibly the main diagonal)
4954:    of a set of rows of a matrix; using local numbering of rows.

4956:    Collective on Mat

4958:    Input Parameters:
4959: +  mat - the matrix
4960: .  is - index set of rows to remove
4961: -  diag - value put in all diagonals of eliminated rows

4963:    Notes:
4964:    Before calling MatZeroRowsLocalIS(), the user must first set the
4965:    local-to-global mapping by calling MatSetLocalToGlobalMapping().

4967:    For the AIJ matrix formats this removes the old nonzero structure,
4968:    but does not release memory.  For the dense and block diagonal
4969:    formats this does not alter the nonzero structure.

4971:    If the option MatSetOption(mat,MAT_KEEP_ZEROED_ROWS,PETSC_TRUE) the nonzero structure
4972:    of the matrix is not changed (even for AIJ and BAIJ matrices) the values are
4973:    merely zeroed.

4975:    The user can set a value in the diagonal entry (or for the AIJ and
4976:    row formats can optionally remove the main diagonal entry from the
4977:    nonzero structure as well, by passing 0.0 as the final argument).

4979:    Level: intermediate

4981:    Concepts: matrices^zeroing

4983: .seealso: MatZeroRows(), MatZeroRowsLocal(), MatZeroEntries(), MatZeroRows(), MatSetLocalToGlobalMapping
4984: @*/
4985: PetscErrorCode  MatZeroRowsLocalIS(Mat mat,IS is,PetscScalar diag)
4986: {
4988:   PetscInt       numRows;
4989:   const PetscInt *rows;

4995:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
4996:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
4997:   MatPreallocated(mat);

4999:   ISGetLocalSize(is,&numRows);
5000:   ISGetIndices(is,&rows);
5001:   MatZeroRowsLocal(mat,numRows,rows,diag);
5002:   ISRestoreIndices(is,&rows);
5003:   return(0);
5004: }

5008: /*@
5009:    MatGetSize - Returns the numbers of rows and columns in a matrix.

5011:    Not Collective

5013:    Input Parameter:
5014: .  mat - the matrix

5016:    Output Parameters:
5017: +  m - the number of global rows
5018: -  n - the number of global columns

5020:    Note: both output parameters can be PETSC_NULL on input.

5022:    Level: beginner

5024:    Concepts: matrices^size

5026: .seealso: MatGetLocalSize()
5027: @*/
5028: PetscErrorCode  MatGetSize(Mat mat,PetscInt *m,PetscInt* n)
5029: {
5032:   if (m) *m = mat->rmap->N;
5033:   if (n) *n = mat->cmap->N;
5034:   return(0);
5035: }

5039: /*@
5040:    MatGetLocalSize - Returns the number of rows and columns in a matrix
5041:    stored locally.  This information may be implementation dependent, so
5042:    use with care.

5044:    Not Collective

5046:    Input Parameters:
5047: .  mat - the matrix

5049:    Output Parameters:
5050: +  m - the number of local rows
5051: -  n - the number of local columns

5053:    Note: both output parameters can be PETSC_NULL on input.

5055:    Level: beginner

5057:    Concepts: matrices^local size

5059: .seealso: MatGetSize()
5060: @*/
5061: PetscErrorCode  MatGetLocalSize(Mat mat,PetscInt *m,PetscInt* n)
5062: {
5067:   if (m) *m = mat->rmap->n;
5068:   if (n) *n = mat->cmap->n;
5069:   return(0);
5070: }

5074: /*@
5075:    MatGetOwnershipRangeColumn - Returns the range of matrix columns owned by
5076:    this processor.

5078:    Not Collective, unless matrix has not been allocated, then collective on Mat

5080:    Input Parameters:
5081: .  mat - the matrix

5083:    Output Parameters:
5084: +  m - the global index of the first local column
5085: -  n - one more than the global index of the last local column

5087:    Notes: both output parameters can be PETSC_NULL on input.

5089:    Level: developer

5091:    Concepts: matrices^column ownership

5093: .seealso:  MatGetOwnershipRange(), MatGetOwnershipRanges(), MatGetOwnershipRangesColumn()

5095: @*/
5096: PetscErrorCode  MatGetOwnershipRangeColumn(Mat mat,PetscInt *m,PetscInt* n)
5097: {

5105:   MatPreallocated(mat);
5106:   if (m) *m = mat->cmap->rstart;
5107:   if (n) *n = mat->cmap->rend;
5108:   return(0);
5109: }

5113: /*@
5114:    MatGetOwnershipRange - Returns the range of matrix rows owned by
5115:    this processor, assuming that the matrix is laid out with the first
5116:    n1 rows on the first processor, the next n2 rows on the second, etc.
5117:    For certain parallel layouts this range may not be well defined.

5119:    Not Collective, unless matrix has not been allocated, then collective on Mat

5121:    Input Parameters:
5122: .  mat - the matrix

5124:    Output Parameters:
5125: +  m - the global index of the first local row
5126: -  n - one more than the global index of the last local row

5128:    Note: both output parameters can be PETSC_NULL on input.

5130:    Level: beginner

5132:    Concepts: matrices^row ownership

5134: .seealso:   MatGetOwnershipRanges(), MatGetOwnershipRangeColumn(), MatGetOwnershipRangesColumn()

5136: @*/
5137: PetscErrorCode  MatGetOwnershipRange(Mat mat,PetscInt *m,PetscInt* n)
5138: {

5146:   MatPreallocated(mat);
5147:   if (m) *m = mat->rmap->rstart;
5148:   if (n) *n = mat->rmap->rend;
5149:   return(0);
5150: }

5154: /*@C
5155:    MatGetOwnershipRanges - Returns the range of matrix rows owned by
5156:    each process

5158:    Not Collective, unless matrix has not been allocated, then collective on Mat

5160:    Input Parameters:
5161: .  mat - the matrix

5163:    Output Parameters:
5164: .  ranges - start of each processors portion plus one more then the total length at the end

5166:    Level: beginner

5168:    Concepts: matrices^row ownership

5170: .seealso:   MatGetOwnershipRange(), MatGetOwnershipRangeColumn(), MatGetOwnershipRangesColumn()

5172: @*/
5173: PetscErrorCode  MatGetOwnershipRanges(Mat mat,const PetscInt **ranges)
5174: {

5180:   MatPreallocated(mat);
5181:   PetscMapGetRanges(mat->rmap,ranges);
5182:   return(0);
5183: }

5187: /*@C
5188:    MatGetOwnershipRangesColumn - Returns the range of local columns for each process

5190:    Not Collective, unless matrix has not been allocated, then collective on Mat

5192:    Input Parameters:
5193: .  mat - the matrix

5195:    Output Parameters:
5196: .  ranges - start of each processors portion plus one more then the total length at the end

5198:    Level: beginner

5200:    Concepts: matrices^column ownership

5202: .seealso:   MatGetOwnershipRange(), MatGetOwnershipRangeColumn(), MatGetOwnershipRanges()

5204: @*/
5205: PetscErrorCode  MatGetOwnershipRangesColumn(Mat mat,const PetscInt **ranges)
5206: {

5212:   MatPreallocated(mat);
5213:   PetscMapGetRanges(mat->cmap,ranges);
5214:   return(0);
5215: }

5219: /*@  
5220:    MatILUFactorSymbolic - Performs symbolic ILU factorization of a matrix.
5221:    Uses levels of fill only, not drop tolerance. Use MatLUFactorNumeric() 
5222:    to complete the factorization.

5224:    Collective on Mat

5226:    Input Parameters:
5227: +  mat - the matrix
5228: .  row - row permutation
5229: .  column - column permutation
5230: -  info - structure containing 
5231: $      levels - number of levels of fill.
5232: $      expected fill - as ratio of original fill.
5233: $      1 or 0 - indicating force fill on diagonal (improves robustness for matrices
5234:                 missing diagonal entries)

5236:    Output Parameters:
5237: .  fact - new matrix that has been symbolically factored

5239:    Notes:
5240:    See the users manual for additional information about
5241:    choosing the fill factor for better efficiency.

5243:    Most users should employ the simplified KSP interface for linear solvers
5244:    instead of working directly with matrix algebra routines such as this.
5245:    See, e.g., KSPCreate().

5247:    Level: developer

5249:   Concepts: matrices^symbolic LU factorization
5250:   Concepts: matrices^factorization
5251:   Concepts: LU^symbolic factorization

5253: .seealso: MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor()
5254:           MatGetOrdering(), MatFactorInfo

5256: @*/
5257: PetscErrorCode  MatILUFactorSymbolic(Mat fact,Mat mat,IS row,IS col,const MatFactorInfo *info)
5258: {

5268:   if (info->levels < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Levels of fill negative %D",(PetscInt)info->levels);
5269:   if (info->fill < 1.0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Expected fill less than 1.0 %G",info->fill);
5270:   if (!(fact)->ops->ilufactorsymbolic) SETERRQ1(PETSC_ERR_SUP,"Matrix type %s  symbolic ILU",((PetscObject)mat)->type_name);
5271:   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
5272:   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
5273:   MatPreallocated(mat);