xref: /petsc/src/mat/utils/gcreate.c (revision dec5475610ed152cc6ab48b797c6d92040b47101)
17807a1faSBarry Smith 
2b45d2f2cSJed Brown #include <petsc-private/matimpl.h>       /*I "petscmat.h"  I*/
37807a1faSBarry Smith 
47adad957SLisandro Dalcin #if 0
54a2ae208SSatish Balay #undef __FUNCT__
64a2ae208SSatish Balay #define __FUNCT__ "MatPublish_Base"
76849ba73SBarry Smith static PetscErrorCode MatPublish_Base(PetscObject obj)
835d8aa7fSBarry Smith {
935d8aa7fSBarry Smith   PetscFunctionBegin;
1035d8aa7fSBarry Smith   PetscFunctionReturn(0);
1135d8aa7fSBarry Smith }
127adad957SLisandro Dalcin #endif
1335d8aa7fSBarry Smith 
144a2ae208SSatish Balay #undef __FUNCT__
154a2ae208SSatish Balay #define __FUNCT__ "MatCreate"
1605869f15SSatish Balay /*@
1769dd0797SLois Curfman McInnes    MatCreate - Creates a matrix where the type is determined
187e5f4302SBarry Smith    from either a call to MatSetType() or from the options database
197e5f4302SBarry Smith    with a call to MatSetFromOptions(). The default matrix type is
2069b1f4b7SBarry Smith    AIJ, using the routines MatCreateSeqAIJ() or MatCreateAIJ()
217e5f4302SBarry Smith    if you do not set a type in the options database. If you never
227e5f4302SBarry Smith    call MatSetType() or MatSetFromOptions() it will generate an
23f8ab6608SSatish Balay    error when you try to use the matrix.
2483e1b59cSLois Curfman McInnes 
25cb13003dSBarry Smith    Collective on MPI_Comm
26cb13003dSBarry Smith 
27f69a0ea3SMatthew Knepley    Input Parameter:
28f69a0ea3SMatthew Knepley .  comm - MPI communicator
297807a1faSBarry Smith 
307807a1faSBarry Smith    Output Parameter:
31dc401e71SLois Curfman McInnes .  A - the matrix
32e0b365e2SLois Curfman McInnes 
33273d9f13SBarry Smith    Options Database Keys:
34273d9f13SBarry Smith +    -mat_type seqaij   - AIJ type, uses MatCreateSeqAIJ()
3569b1f4b7SBarry Smith .    -mat_type mpiaij   - AIJ type, uses MatCreateAIJ()
36273d9f13SBarry Smith .    -mat_type seqdense - dense type, uses MatCreateSeqDense()
3769b1f4b7SBarry Smith .    -mat_type mpidense - dense type, uses MatCreateDense()
38273d9f13SBarry Smith .    -mat_type seqbaij  - block AIJ type, uses MatCreateSeqBAIJ()
3969b1f4b7SBarry Smith -    -mat_type mpibaij  - block AIJ type, uses MatCreateBAIJ()
40e0b365e2SLois Curfman McInnes 
4183e1b59cSLois Curfman McInnes    Even More Options Database Keys:
4283e1b59cSLois Curfman McInnes    See the manpages for particular formats (e.g., MatCreateSeqAIJ())
4383e1b59cSLois Curfman McInnes    for additional format-specific options.
44e0b365e2SLois Curfman McInnes 
45bd9ce289SLois Curfman McInnes    Notes:
46ec6e0d80SSatish Balay 
47273d9f13SBarry Smith    Level: beginner
48273d9f13SBarry Smith 
49a2fc510eSBarry Smith    User manual sections:
50a2fc510eSBarry Smith +   sec_matcreate
51a2fc510eSBarry Smith -   chapter_matrices
52a2fc510eSBarry Smith 
53273d9f13SBarry Smith .keywords: matrix, create
54273d9f13SBarry Smith 
5569b1f4b7SBarry Smith .seealso: MatCreateSeqAIJ(), MatCreateAIJ(),
5669b1f4b7SBarry Smith           MatCreateSeqDense(), MatCreateDense(),
5769b1f4b7SBarry Smith           MatCreateSeqBAIJ(), MatCreateBAIJ(),
5869b1f4b7SBarry Smith           MatCreateSeqSBAIJ(), MatCreateSBAIJ(),
59273d9f13SBarry Smith           MatConvert()
60273d9f13SBarry Smith @*/
617087cfbeSBarry Smith PetscErrorCode  MatCreate(MPI_Comm comm,Mat *A)
62273d9f13SBarry Smith {
63273d9f13SBarry Smith   Mat            B;
64dfbe8321SBarry Smith   PetscErrorCode ierr;
65273d9f13SBarry Smith 
66273d9f13SBarry Smith   PetscFunctionBegin;
67f69a0ea3SMatthew Knepley   PetscValidPointer(A,2);
6897f1f81fSBarry Smith 
698ba1e511SMatthew Knepley   *A = PETSC_NULL;
708ba1e511SMatthew Knepley #ifndef PETSC_USE_DYNAMIC_LIBRARIES
718ba1e511SMatthew Knepley   ierr = MatInitializePackage(PETSC_NULL);CHKERRQ(ierr);
728ba1e511SMatthew Knepley #endif
738ba1e511SMatthew Knepley 
743194b578SJed Brown   ierr = PetscHeaderCreate(B,_p_Mat,struct _MatOps,MAT_CLASSID,0,"Mat","Matrix","Mat",comm,MatDestroy,MatView);CHKERRQ(ierr);
7526283091SBarry Smith   ierr = PetscLayoutCreate(comm,&B->rmap);CHKERRQ(ierr);
7626283091SBarry Smith   ierr = PetscLayoutCreate(comm,&B->cmap);CHKERRQ(ierr);
77273d9f13SBarry Smith   B->preallocated  = PETSC_FALSE;
78273d9f13SBarry Smith   *A               = B;
79273d9f13SBarry Smith   PetscFunctionReturn(0);
80273d9f13SBarry Smith }
81273d9f13SBarry Smith 
824a2ae208SSatish Balay #undef __FUNCT__
83f69a0ea3SMatthew Knepley #define __FUNCT__ "MatSetSizes"
84f69a0ea3SMatthew Knepley /*@
85f69a0ea3SMatthew Knepley   MatSetSizes - Sets the local and global sizes, and checks to determine compatibility
86f69a0ea3SMatthew Knepley 
87f69a0ea3SMatthew Knepley   Collective on Mat
88f69a0ea3SMatthew Knepley 
89f69a0ea3SMatthew Knepley   Input Parameters:
90f69a0ea3SMatthew Knepley +  A - the matrix
91f69a0ea3SMatthew Knepley .  m - number of local rows (or PETSC_DECIDE)
92f69a0ea3SMatthew Knepley .  n - number of local columns (or PETSC_DECIDE)
93f69a0ea3SMatthew Knepley .  M - number of global rows (or PETSC_DETERMINE)
94f69a0ea3SMatthew Knepley -  N - number of global columns (or PETSC_DETERMINE)
95f69a0ea3SMatthew Knepley 
96f69a0ea3SMatthew Knepley    Notes:
97f69a0ea3SMatthew Knepley    m (n) and M (N) cannot be both PETSC_DECIDE
98f69a0ea3SMatthew Knepley    If one processor calls this with M (N) of PETSC_DECIDE then all processors must, otherwise the program will hang.
99f69a0ea3SMatthew Knepley 
100f69a0ea3SMatthew Knepley    If PETSC_DECIDE is not used for the arguments 'm' and 'n', then the
101f69a0ea3SMatthew Knepley    user must ensure that they are chosen to be compatible with the
102f69a0ea3SMatthew Knepley    vectors. To do this, one first considers the matrix-vector product
103f69a0ea3SMatthew Knepley    'y = A x'. The 'm' that is used in the above routine must match the
104f69a0ea3SMatthew Knepley    local size used in the vector creation routine VecCreateMPI() for 'y'.
105f69a0ea3SMatthew Knepley    Likewise, the 'n' used must match that used as the local size in
106f69a0ea3SMatthew Knepley    VecCreateMPI() for 'x'.
107f69a0ea3SMatthew Knepley 
108f73d5cc4SBarry Smith    You cannot change the sizes once they have been set.
109f73d5cc4SBarry Smith 
110f73d5cc4SBarry Smith    The sizes must be set before MatSetUp() or MatXXXSetPreallocation() is called.
111f73d5cc4SBarry Smith 
112f69a0ea3SMatthew Knepley   Level: beginner
113f69a0ea3SMatthew Knepley 
114f69a0ea3SMatthew Knepley .seealso: MatGetSize(), PetscSplitOwnership()
115f69a0ea3SMatthew Knepley @*/
1167087cfbeSBarry Smith PetscErrorCode  MatSetSizes(Mat A, PetscInt m, PetscInt n, PetscInt M, PetscInt N)
117f69a0ea3SMatthew Knepley {
118f69a0ea3SMatthew Knepley   PetscFunctionBegin;
1190700a824SBarry Smith   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
120e32f2f54SBarry Smith   if (M > 0 && m > M) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Local column size %D cannot be larger than global column size %D",m,M);
121e32f2f54SBarry Smith   if (N > 0 && n > N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Local row size %D cannot be larger than global row size %D",n,N);
122e32f2f54SBarry Smith   if ((A->rmap->n >= 0 || A->rmap->N >= 0) && (A->rmap->n != m || A->rmap->N != M)) SETERRQ4(PETSC_COMM_SELF,PETSC_ERR_SUP,"Cannot change/reset row sizes to %D local %D global after previously setting them to %D local %D global",m,M,A->rmap->n,A->rmap->N);
123e32f2f54SBarry Smith   if ((A->cmap->n >= 0 || A->cmap->N >= 0) && (A->cmap->n != n || A->cmap->N != N)) SETERRQ4(PETSC_COMM_SELF,PETSC_ERR_SUP,"Cannot change/reset column sizes to %D local %D global after previously setting them to %D local %D global",n,N,A->cmap->n,A->cmap->N);
124d0f46423SBarry Smith   A->rmap->n = m;
125d0f46423SBarry Smith   A->cmap->n = n;
126d0f46423SBarry Smith   A->rmap->N = M;
127d0f46423SBarry Smith   A->cmap->N = N;
128f69a0ea3SMatthew Knepley   PetscFunctionReturn(0);
129f69a0ea3SMatthew Knepley }
130f69a0ea3SMatthew Knepley 
131f69a0ea3SMatthew Knepley #undef __FUNCT__
1324a2ae208SSatish Balay #define __FUNCT__ "MatSetFromOptions"
13305869f15SSatish Balay /*@
134273d9f13SBarry Smith    MatSetFromOptions - Creates a matrix where the type is determined
135273d9f13SBarry Smith    from the options database. Generates a parallel MPI matrix if the
136273d9f13SBarry Smith    communicator has more than one processor.  The default matrix type is
13769b1f4b7SBarry Smith    AIJ, using the routines MatCreateSeqAIJ() and MatCreateAIJ() if
1387e5f4302SBarry Smith    you do not select a type in the options database.
139273d9f13SBarry Smith 
140273d9f13SBarry Smith    Collective on Mat
141273d9f13SBarry Smith 
142273d9f13SBarry Smith    Input Parameter:
143273d9f13SBarry Smith .  A - the matrix
144273d9f13SBarry Smith 
145273d9f13SBarry Smith    Options Database Keys:
146273d9f13SBarry Smith +    -mat_type seqaij   - AIJ type, uses MatCreateSeqAIJ()
14769b1f4b7SBarry Smith .    -mat_type mpiaij   - AIJ type, uses MatCreateAIJ()
148273d9f13SBarry Smith .    -mat_type seqdense - dense type, uses MatCreateSeqDense()
14969b1f4b7SBarry Smith .    -mat_type mpidense - dense type, uses MatCreateDense()
150273d9f13SBarry Smith .    -mat_type seqbaij  - block AIJ type, uses MatCreateSeqBAIJ()
15169b1f4b7SBarry Smith -    -mat_type mpibaij  - block AIJ type, uses MatCreateBAIJ()
152273d9f13SBarry Smith 
153273d9f13SBarry Smith    Even More Options Database Keys:
154273d9f13SBarry Smith    See the manpages for particular formats (e.g., MatCreateSeqAIJ())
155273d9f13SBarry Smith    for additional format-specific options.
156bd9ce289SLois Curfman McInnes 
1571d69843bSLois Curfman McInnes    Level: beginner
1581d69843bSLois Curfman McInnes 
159dc401e71SLois Curfman McInnes .keywords: matrix, create
160e0b365e2SLois Curfman McInnes 
16169b1f4b7SBarry Smith .seealso: MatCreateSeqAIJ((), MatCreateAIJ(),
16269b1f4b7SBarry Smith           MatCreateSeqDense(), MatCreateDense(),
16369b1f4b7SBarry Smith           MatCreateSeqBAIJ(), MatCreateBAIJ(),
16469b1f4b7SBarry Smith           MatCreateSeqSBAIJ(), MatCreateSBAIJ(),
165273d9f13SBarry Smith           MatConvert()
1667807a1faSBarry Smith @*/
1677087cfbeSBarry Smith PetscErrorCode  MatSetFromOptions(Mat B)
1687807a1faSBarry Smith {
169dfbe8321SBarry Smith   PetscErrorCode ierr;
170f3be49caSLisandro Dalcin   const char     *deft = MATAIJ;
171f3be49caSLisandro Dalcin   char           type[256];
17269df5c0cSJed Brown   PetscBool      flg,set;
173dbb450caSBarry Smith 
1743a40ed3dSBarry Smith   PetscFunctionBegin;
1750700a824SBarry Smith   PetscValidHeaderSpecific(B,MAT_CLASSID,1);
176f3be49caSLisandro Dalcin 
1773194b578SJed Brown   ierr = PetscObjectOptionsBegin((PetscObject)B);CHKERRQ(ierr);
178535b19f3SBarry Smith 
179535b19f3SBarry Smith     if (B->rmap->bs < 0) {
180535b19f3SBarry Smith       PetscInt newbs = -1;
181535b19f3SBarry Smith       ierr = PetscOptionsInt("-mat_block_size","Set the blocksize used to store the matrix","MatSetBlockSize",newbs,&newbs,&flg);CHKERRQ(ierr);
182535b19f3SBarry Smith       if (flg) {
183535b19f3SBarry Smith         ierr = PetscLayoutSetBlockSize(B->rmap,newbs);CHKERRQ(ierr);
184535b19f3SBarry Smith         ierr = PetscLayoutSetBlockSize(B->cmap,newbs);CHKERRQ(ierr);
185535b19f3SBarry Smith       }
186535b19f3SBarry Smith     }
187535b19f3SBarry Smith 
188f3be49caSLisandro Dalcin     ierr = PetscOptionsList("-mat_type","Matrix type","MatSetType",MatList,deft,type,256,&flg);CHKERRQ(ierr);
189273d9f13SBarry Smith     if (flg) {
190f3be49caSLisandro Dalcin       ierr = MatSetType(B,type);CHKERRQ(ierr);
191f3be49caSLisandro Dalcin     } else if (!((PetscObject)B)->type_name) {
192f3be49caSLisandro Dalcin       ierr = MatSetType(B,deft);CHKERRQ(ierr);
193273d9f13SBarry Smith     }
194f3be49caSLisandro Dalcin 
195f3be49caSLisandro Dalcin     if (B->ops->setfromoptions) {
196f3be49caSLisandro Dalcin       ierr = (*B->ops->setfromoptions)(B);CHKERRQ(ierr);
197593c1905SSatish Balay     }
198f3be49caSLisandro Dalcin 
19969df5c0cSJed Brown     flg = PETSC_FALSE;
20069df5c0cSJed Brown     ierr = PetscOptionsBool("-mat_new_nonzero_location_err","Generate an error if new nonzeros are created in the matrix structure (useful to test preallocation)","MatSetOption",flg,&flg,&set);CHKERRQ(ierr);
20169df5c0cSJed Brown     if (set) {ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,flg);CHKERRQ(ierr);}
20269df5c0cSJed Brown     flg = PETSC_FALSE;
20369df5c0cSJed Brown     ierr = PetscOptionsBool("-mat_new_nonzero_allocation_err","Generate an error if new nonzeros are allocated in the matrix structure (useful to test preallocation)","MatSetOption",flg,&flg,&set);CHKERRQ(ierr);
20469df5c0cSJed Brown     if (set) {ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,flg);CHKERRQ(ierr);}
20569df5c0cSJed Brown 
2065d973c19SBarry Smith     /* process any options handlers added with PetscObjectAddOptionsHandler() */
2075d973c19SBarry Smith     ierr = PetscObjectProcessOptionsHandlers((PetscObject)B);CHKERRQ(ierr);
208f3be49caSLisandro Dalcin   ierr = PetscOptionsEnd();CHKERRQ(ierr);
209f3be49caSLisandro Dalcin 
2103a40ed3dSBarry Smith   PetscFunctionReturn(0);
2117807a1faSBarry Smith }
2127807a1faSBarry Smith 
2134a2ae208SSatish Balay #undef __FUNCT__
21463562e91SJed Brown #define __FUNCT__ "MatXAIJSetPreallocation"
21563562e91SJed Brown /*@
21663562e91SJed Brown    MatXAIJSetPreallocation - set preallocation for serial and parallel AIJ, BAIJ, and SBAIJ matrices
21763562e91SJed Brown 
21863562e91SJed Brown    Collective on Mat
21963562e91SJed Brown 
22063562e91SJed Brown    Input Arguments:
22163562e91SJed Brown +  A - matrix being preallocated
22263562e91SJed Brown .  bs - block size
2233e5f4774SJed Brown .  dnnz - number of nonzero blocks per block row of diagonal part of parallel matrix
2243e5f4774SJed Brown .  onnz - number of nonzero blocks per block row of off-diagonal part of parallel matrix
2253e5f4774SJed Brown .  dnnzu - number of nonzero blocks per block row of upper-triangular part of diagonal part of parallel matrix
2263e5f4774SJed Brown -  onnzu - number of nonzero blocks per block row of upper-triangular part of off-diagonal part of parallel matrix
22763562e91SJed Brown 
22863562e91SJed Brown    Level: beginner
22963562e91SJed Brown 
23063562e91SJed Brown .seealso: MatSeqAIJSetPreallocation(), MatMPIAIJSetPreallocation(), MatSeqBAIJSetPreallocation(), MatMPIBAIJSetPreallocation(), MatSeqSBAIJSetPreallocation(), MatMPISBAIJSetPreallocation()
23163562e91SJed Brown @*/
2323e5f4774SJed Brown PetscErrorCode MatXAIJSetPreallocation(Mat A,PetscInt bs,const PetscInt *dnnz,const PetscInt *onnz,const PetscInt *dnnzu,const PetscInt *onnzu)
23363562e91SJed Brown {
23463562e91SJed Brown   PetscErrorCode ierr;
23563562e91SJed Brown   void (*aij)(void);
23663562e91SJed Brown 
23763562e91SJed Brown   PetscFunctionBegin;
238*dec54756SJed Brown   ierr = MatSetBlockSize(A,bs);CHKERRQ(ierr);
239*dec54756SJed Brown   ierr = PetscLayoutSetUp(A->rmap);CHKERRQ(ierr);
240*dec54756SJed Brown   ierr = PetscLayoutSetUp(A->cmap);CHKERRQ(ierr);
2413e5f4774SJed Brown   ierr = MatSeqBAIJSetPreallocation(A,bs,0,dnnz);CHKERRQ(ierr);
2423e5f4774SJed Brown   ierr = MatMPIBAIJSetPreallocation(A,bs,0,dnnz,0,onnz);CHKERRQ(ierr);
2433e5f4774SJed Brown   ierr = MatSeqSBAIJSetPreallocation(A,bs,0,dnnzu);CHKERRQ(ierr);
2443e5f4774SJed Brown   ierr = MatMPISBAIJSetPreallocation(A,bs,0,dnnzu,0,onnzu);CHKERRQ(ierr);
24563562e91SJed Brown   /*
24663562e91SJed Brown     In general, we have to do extra work to preallocate for scalar (AIJ) matrices so we check whether it will do any
24763562e91SJed Brown     good before going on with it.
24863562e91SJed Brown   */
24963562e91SJed Brown   ierr = PetscObjectQueryFunction((PetscObject)A,"MatMPIAIJSetPreallocation_C",&aij);CHKERRQ(ierr);
25063562e91SJed Brown   if (!aij) {
25163562e91SJed Brown     ierr = PetscObjectQueryFunction((PetscObject)A,"MatSeqAIJSetPreallocation_C",&aij);CHKERRQ(ierr);
25263562e91SJed Brown   }
25363562e91SJed Brown   if (aij) {
25463562e91SJed Brown     if (bs == 1) {
2553e5f4774SJed Brown       ierr = MatSeqAIJSetPreallocation(A,0,dnnz);CHKERRQ(ierr);
2563e5f4774SJed Brown       ierr = MatMPIAIJSetPreallocation(A,0,dnnz,0,onnz);CHKERRQ(ierr);
2573e5f4774SJed Brown     } else {                    /* Convert block-row precallocation to scalar-row */
25863562e91SJed Brown       PetscInt i,m,*sdnnz,*sonnz;
25963562e91SJed Brown       ierr = MatGetLocalSize(A,&m,PETSC_NULL);CHKERRQ(ierr);
260*dec54756SJed Brown       ierr = PetscMalloc2((!!dnnz)*m,PetscInt,&sdnnz,(!!onnz)*m,PetscInt,&sonnz);CHKERRQ(ierr);
261*dec54756SJed Brown       for (i=0; i<m; i++) {
26263562e91SJed Brown         if (dnnz) sdnnz[i] = dnnz[i/bs] * bs;
26363562e91SJed Brown         if (onnz) sonnz[i] = onnz[i/bs] * bs;
26463562e91SJed Brown       }
2653e5f4774SJed Brown       ierr = MatSeqAIJSetPreallocation(A,0,dnnz?sdnnz:PETSC_NULL);CHKERRQ(ierr);
2663e5f4774SJed Brown       ierr = MatMPIAIJSetPreallocation(A,0,dnnz?sdnnz:PETSC_NULL,0,onnz?sonnz:PETSC_NULL);CHKERRQ(ierr);
26763562e91SJed Brown       ierr = PetscFree2(sdnnz,sonnz);CHKERRQ(ierr);
26863562e91SJed Brown     }
26963562e91SJed Brown   }
27063562e91SJed Brown   PetscFunctionReturn(0);
27163562e91SJed Brown }
27263562e91SJed Brown 
273273d9f13SBarry Smith /*
274eb6b5d47SBarry Smith         Merges some information from Cs header to A; the C object is then destroyed
275d0f46423SBarry Smith 
276d0f46423SBarry Smith         This is somewhat different from MatHeaderReplace() it would be nice to merge the code
277273d9f13SBarry Smith */
2784a2ae208SSatish Balay #undef __FUNCT__
279eb6b5d47SBarry Smith #define __FUNCT__ "MatHeaderMerge"
280eb6b5d47SBarry Smith PetscErrorCode MatHeaderMerge(Mat A,Mat C)
281273d9f13SBarry Smith {
282dfbe8321SBarry Smith   PetscErrorCode         ierr;
283d44834fbSBarry Smith   PetscInt               refct;
284273d9f13SBarry Smith   PetscOps               *Abops;
285273d9f13SBarry Smith   MatOps                 Aops;
286273d9f13SBarry Smith   char                   *mtype,*mname;
28730735b05SKris Buschelman   void                   *spptr;
288273d9f13SBarry Smith 
289273d9f13SBarry Smith   PetscFunctionBegin;
290273d9f13SBarry Smith   /* save the parts of A we need */
2917adad957SLisandro Dalcin   Abops = ((PetscObject)A)->bops;
292273d9f13SBarry Smith   Aops  = A->ops;
2937adad957SLisandro Dalcin   refct = ((PetscObject)A)->refct;
2945c9eb25fSBarry Smith   mtype = ((PetscObject)A)->type_name;
2955c9eb25fSBarry Smith   mname = ((PetscObject)A)->name;
29630735b05SKris Buschelman   spptr = A->spptr;
29730735b05SKris Buschelman 
2985c9eb25fSBarry Smith   /* zero these so the destroy below does not free them */
2995c9eb25fSBarry Smith   ((PetscObject)A)->type_name = 0;
3005c9eb25fSBarry Smith   ((PetscObject)A)->name      = 0;
3015c9eb25fSBarry Smith 
3027c99f97cSSatish Balay   /* free all the interior data structures from mat */
3037c99f97cSSatish Balay   ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
3047c99f97cSSatish Balay 
30530735b05SKris Buschelman   ierr = PetscFree(C->spptr);CHKERRQ(ierr);
30605b42c5fSBarry Smith 
3076bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->rmap);CHKERRQ(ierr);
3086bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->cmap);CHKERRQ(ierr);
3095c9eb25fSBarry Smith   ierr = PetscFListDestroy(&((PetscObject)A)->qlist);CHKERRQ(ierr);
3106bf464f9SBarry Smith   ierr = PetscOListDestroy(&((PetscObject)A)->olist);CHKERRQ(ierr);
311273d9f13SBarry Smith 
312273d9f13SBarry Smith   /* copy C over to A */
313273d9f13SBarry Smith   ierr  = PetscMemcpy(A,C,sizeof(struct _p_Mat));CHKERRQ(ierr);
314273d9f13SBarry Smith 
315273d9f13SBarry Smith   /* return the parts of A we saved */
3167adad957SLisandro Dalcin   ((PetscObject)A)->bops      = Abops;
317273d9f13SBarry Smith   A->ops                      = Aops;
3187adad957SLisandro Dalcin   ((PetscObject)A)->refct     = refct;
3197adad957SLisandro Dalcin   ((PetscObject)A)->type_name = mtype;
3207adad957SLisandro Dalcin   ((PetscObject)A)->name      = mname;
32130735b05SKris Buschelman   A->spptr                    = spptr;
322273d9f13SBarry Smith 
3235c9eb25fSBarry Smith   /* since these two are copied into A we do not want them destroyed in C */
3245c9eb25fSBarry Smith   ((PetscObject)C)->qlist = 0;
3255c9eb25fSBarry Smith   ((PetscObject)C)->olist = 0;
3266bf464f9SBarry Smith   ierr = PetscHeaderDestroy(&C);CHKERRQ(ierr);
327273d9f13SBarry Smith   PetscFunctionReturn(0);
328273d9f13SBarry Smith }
3298ab5b326SKris Buschelman /*
330eb6b5d47SBarry Smith         Replace A's header with that of C; the C object is then destroyed
331d0f46423SBarry Smith 
332eb6b5d47SBarry Smith         This is essentially code moved from MatDestroy()
333eb6b5d47SBarry Smith 
334eb6b5d47SBarry Smith         This is somewhat different from MatHeaderMerge() it would be nice to merge the code
3358ab5b326SKris Buschelman */
3368ab5b326SKris Buschelman #undef __FUNCT__
3378ab5b326SKris Buschelman #define __FUNCT__ "MatHeaderReplace"
3388ab5b326SKris Buschelman PetscErrorCode MatHeaderReplace(Mat A,Mat C)
3398ab5b326SKris Buschelman {
3408ab5b326SKris Buschelman   PetscErrorCode ierr;
34127b31e29SJed Brown   PetscInt refct;
3428ab5b326SKris Buschelman 
3438ab5b326SKris Buschelman   PetscFunctionBegin;
34427b31e29SJed Brown   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
34527b31e29SJed Brown   PetscValidHeaderSpecific(C,MAT_CLASSID,2);
3466d7c1e57SBarry Smith   if (A == C) PetscFunctionReturn(0);
347a7e80f87SJed Brown   PetscCheckSameComm(A,1,C,2);
348a7e80f87SJed Brown   if (((PetscObject)C)->refct != 1) SETERRQ1(((PetscObject)C)->comm,PETSC_ERR_ARG_WRONGSTATE,"Object C has refct %D > 1, would leave hanging reference",((PetscObject)C)->refct);
3496d7c1e57SBarry Smith 
3508ab5b326SKris Buschelman   /* free all the interior data structures from mat */
3518ab5b326SKris Buschelman   ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
352d2c95936SBarry Smith   ierr = PetscHeaderDestroy_Private((PetscObject)A);CHKERRQ(ierr);
353c650bb5fSLisandro Dalcin   ierr = PetscFree(A->ops);CHKERRQ(ierr);
3546bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->rmap);CHKERRQ(ierr);
3556bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->cmap);CHKERRQ(ierr);
356d95db058SSatish Balay   ierr = PetscFree(A->spptr);CHKERRQ(ierr);
3578ab5b326SKris Buschelman 
3588ab5b326SKris Buschelman   /* copy C over to A */
35927b31e29SJed Brown   refct = ((PetscObject)A)->refct;
3608ab5b326SKris Buschelman   ierr = PetscMemcpy(A,C,sizeof(struct _p_Mat));CHKERRQ(ierr);
36127b31e29SJed Brown   ((PetscObject)A)->refct = refct;
3628ab5b326SKris Buschelman   ierr = PetscLogObjectDestroy((PetscObject)C);CHKERRQ(ierr);
3638ab5b326SKris Buschelman   ierr = PetscFree(C);CHKERRQ(ierr);
3648ab5b326SKris Buschelman   PetscFunctionReturn(0);
3658ab5b326SKris Buschelman }
366