xref: /petsc/src/mat/utils/gcreate.c (revision b45d2f2cb7e031d9c0de5873eca80614ca7b863b)
17807a1faSBarry Smith 
2*b45d2f2cSJed 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 
108f69a0ea3SMatthew Knepley   Level: beginner
109f69a0ea3SMatthew Knepley 
110f69a0ea3SMatthew Knepley .seealso: MatGetSize(), PetscSplitOwnership()
111f69a0ea3SMatthew Knepley @*/
1127087cfbeSBarry Smith PetscErrorCode  MatSetSizes(Mat A, PetscInt m, PetscInt n, PetscInt M, PetscInt N)
113f69a0ea3SMatthew Knepley {
114284134d9SBarry Smith   PetscErrorCode ierr;
115284134d9SBarry Smith 
116f69a0ea3SMatthew Knepley   PetscFunctionBegin;
1170700a824SBarry Smith   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
118e32f2f54SBarry 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);
119e32f2f54SBarry 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);
120284134d9SBarry Smith   if (A->ops->setsizes) {
121284134d9SBarry Smith     /* Since this will not be set until the type has been set, this will NOT be called on the initial
122284134d9SBarry Smith        call of MatSetSizes() (which must be called BEFORE MatSetType() */
123284134d9SBarry Smith     ierr = (*A->ops->setsizes)(A,m,n,M,N);CHKERRQ(ierr);
124284134d9SBarry Smith   } else {
125e32f2f54SBarry 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);
126e32f2f54SBarry 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);
127284134d9SBarry Smith   }
128d0f46423SBarry Smith   A->rmap->n = m;
129d0f46423SBarry Smith   A->cmap->n = n;
130d0f46423SBarry Smith   A->rmap->N = M;
131d0f46423SBarry Smith   A->cmap->N = N;
132117016b1SBarry Smith 
133f69a0ea3SMatthew Knepley   PetscFunctionReturn(0);
134f69a0ea3SMatthew Knepley }
135f69a0ea3SMatthew Knepley 
136f69a0ea3SMatthew Knepley #undef __FUNCT__
1374a2ae208SSatish Balay #define __FUNCT__ "MatSetFromOptions"
13805869f15SSatish Balay /*@
139273d9f13SBarry Smith    MatSetFromOptions - Creates a matrix where the type is determined
140273d9f13SBarry Smith    from the options database. Generates a parallel MPI matrix if the
141273d9f13SBarry Smith    communicator has more than one processor.  The default matrix type is
14269b1f4b7SBarry Smith    AIJ, using the routines MatCreateSeqAIJ() and MatCreateAIJ() if
1437e5f4302SBarry Smith    you do not select a type in the options database.
144273d9f13SBarry Smith 
145273d9f13SBarry Smith    Collective on Mat
146273d9f13SBarry Smith 
147273d9f13SBarry Smith    Input Parameter:
148273d9f13SBarry Smith .  A - the matrix
149273d9f13SBarry Smith 
150273d9f13SBarry Smith    Options Database Keys:
151273d9f13SBarry Smith +    -mat_type seqaij   - AIJ type, uses MatCreateSeqAIJ()
15269b1f4b7SBarry Smith .    -mat_type mpiaij   - AIJ type, uses MatCreateAIJ()
153273d9f13SBarry Smith .    -mat_type seqdense - dense type, uses MatCreateSeqDense()
15469b1f4b7SBarry Smith .    -mat_type mpidense - dense type, uses MatCreateDense()
155273d9f13SBarry Smith .    -mat_type seqbaij  - block AIJ type, uses MatCreateSeqBAIJ()
15669b1f4b7SBarry Smith -    -mat_type mpibaij  - block AIJ type, uses MatCreateBAIJ()
157273d9f13SBarry Smith 
158273d9f13SBarry Smith    Even More Options Database Keys:
159273d9f13SBarry Smith    See the manpages for particular formats (e.g., MatCreateSeqAIJ())
160273d9f13SBarry Smith    for additional format-specific options.
161bd9ce289SLois Curfman McInnes 
1621d69843bSLois Curfman McInnes    Level: beginner
1631d69843bSLois Curfman McInnes 
164dc401e71SLois Curfman McInnes .keywords: matrix, create
165e0b365e2SLois Curfman McInnes 
16669b1f4b7SBarry Smith .seealso: MatCreateSeqAIJ((), MatCreateAIJ(),
16769b1f4b7SBarry Smith           MatCreateSeqDense(), MatCreateDense(),
16869b1f4b7SBarry Smith           MatCreateSeqBAIJ(), MatCreateBAIJ(),
16969b1f4b7SBarry Smith           MatCreateSeqSBAIJ(), MatCreateSBAIJ(),
170273d9f13SBarry Smith           MatConvert()
1717807a1faSBarry Smith @*/
1727087cfbeSBarry Smith PetscErrorCode  MatSetFromOptions(Mat B)
1737807a1faSBarry Smith {
174dfbe8321SBarry Smith   PetscErrorCode ierr;
175f3be49caSLisandro Dalcin   const char     *deft = MATAIJ;
176f3be49caSLisandro Dalcin   char           type[256];
17769df5c0cSJed Brown   PetscBool      flg,set;
178dbb450caSBarry Smith 
1793a40ed3dSBarry Smith   PetscFunctionBegin;
1800700a824SBarry Smith   PetscValidHeaderSpecific(B,MAT_CLASSID,1);
181f3be49caSLisandro Dalcin 
1823194b578SJed Brown   ierr = PetscObjectOptionsBegin((PetscObject)B);CHKERRQ(ierr);
183f3be49caSLisandro Dalcin     ierr = PetscOptionsList("-mat_type","Matrix type","MatSetType",MatList,deft,type,256,&flg);CHKERRQ(ierr);
184273d9f13SBarry Smith     if (flg) {
185f3be49caSLisandro Dalcin       ierr = MatSetType(B,type);CHKERRQ(ierr);
186f3be49caSLisandro Dalcin     } else if (!((PetscObject)B)->type_name) {
187f3be49caSLisandro Dalcin       ierr = MatSetType(B,deft);CHKERRQ(ierr);
188273d9f13SBarry Smith     }
189f3be49caSLisandro Dalcin 
190f3be49caSLisandro Dalcin     if (B->ops->setfromoptions) {
191f3be49caSLisandro Dalcin       ierr = (*B->ops->setfromoptions)(B);CHKERRQ(ierr);
192593c1905SSatish Balay     }
193f3be49caSLisandro Dalcin 
19469df5c0cSJed Brown     flg = PETSC_FALSE;
19569df5c0cSJed 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);
19669df5c0cSJed Brown     if (set) {ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,flg);CHKERRQ(ierr);}
19769df5c0cSJed Brown     flg = PETSC_FALSE;
19869df5c0cSJed 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);
19969df5c0cSJed Brown     if (set) {ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,flg);CHKERRQ(ierr);}
20069df5c0cSJed Brown 
2015d973c19SBarry Smith     /* process any options handlers added with PetscObjectAddOptionsHandler() */
2025d973c19SBarry Smith     ierr = PetscObjectProcessOptionsHandlers((PetscObject)B);CHKERRQ(ierr);
203f3be49caSLisandro Dalcin   ierr = PetscOptionsEnd();CHKERRQ(ierr);
204f3be49caSLisandro Dalcin 
2053a40ed3dSBarry Smith   PetscFunctionReturn(0);
2067807a1faSBarry Smith }
2077807a1faSBarry Smith 
2084a2ae208SSatish Balay #undef __FUNCT__
20963562e91SJed Brown #define __FUNCT__ "MatXAIJSetPreallocation"
21063562e91SJed Brown /*@
21163562e91SJed Brown    MatXAIJSetPreallocation - set preallocation for serial and parallel AIJ, BAIJ, and SBAIJ matrices
21263562e91SJed Brown 
21363562e91SJed Brown    Collective on Mat
21463562e91SJed Brown 
21563562e91SJed Brown    Input Arguments:
21663562e91SJed Brown +  A - matrix being preallocated
21763562e91SJed Brown .  bs - block size
2183e5f4774SJed Brown .  dnnz - number of nonzero blocks per block row of diagonal part of parallel matrix
2193e5f4774SJed Brown .  onnz - number of nonzero blocks per block row of off-diagonal part of parallel matrix
2203e5f4774SJed Brown .  dnnzu - number of nonzero blocks per block row of upper-triangular part of diagonal part of parallel matrix
2213e5f4774SJed Brown -  onnzu - number of nonzero blocks per block row of upper-triangular part of off-diagonal part of parallel matrix
22263562e91SJed Brown 
22363562e91SJed Brown    Level: beginner
22463562e91SJed Brown 
22563562e91SJed Brown .seealso: MatSeqAIJSetPreallocation(), MatMPIAIJSetPreallocation(), MatSeqBAIJSetPreallocation(), MatMPIBAIJSetPreallocation(), MatSeqSBAIJSetPreallocation(), MatMPISBAIJSetPreallocation()
22663562e91SJed Brown @*/
2273e5f4774SJed Brown PetscErrorCode MatXAIJSetPreallocation(Mat A,PetscInt bs,const PetscInt *dnnz,const PetscInt *onnz,const PetscInt *dnnzu,const PetscInt *onnzu)
22863562e91SJed Brown {
22963562e91SJed Brown   PetscErrorCode ierr;
23063562e91SJed Brown   void (*aij)(void);
23163562e91SJed Brown 
23263562e91SJed Brown   PetscFunctionBegin;
2333e5f4774SJed Brown   ierr = MatSeqBAIJSetPreallocation(A,bs,0,dnnz);CHKERRQ(ierr);
2343e5f4774SJed Brown   ierr = MatMPIBAIJSetPreallocation(A,bs,0,dnnz,0,onnz);CHKERRQ(ierr);
2353e5f4774SJed Brown   ierr = MatSeqSBAIJSetPreallocation(A,bs,0,dnnzu);CHKERRQ(ierr);
2363e5f4774SJed Brown   ierr = MatMPISBAIJSetPreallocation(A,bs,0,dnnzu,0,onnzu);CHKERRQ(ierr);
23763562e91SJed Brown   /*
23863562e91SJed Brown     In general, we have to do extra work to preallocate for scalar (AIJ) matrices so we check whether it will do any
23963562e91SJed Brown     good before going on with it.
24063562e91SJed Brown   */
24163562e91SJed Brown   ierr = PetscObjectQueryFunction((PetscObject)A,"MatMPIAIJSetPreallocation_C",&aij);CHKERRQ(ierr);
24263562e91SJed Brown   if (!aij) {
24363562e91SJed Brown     ierr = PetscObjectQueryFunction((PetscObject)A,"MatSeqAIJSetPreallocation_C",&aij);CHKERRQ(ierr);
24463562e91SJed Brown   }
24563562e91SJed Brown   if (aij) {
24663562e91SJed Brown     if (bs == 1) {
2473e5f4774SJed Brown       ierr = MatSeqAIJSetPreallocation(A,0,dnnz);CHKERRQ(ierr);
2483e5f4774SJed Brown       ierr = MatMPIAIJSetPreallocation(A,0,dnnz,0,onnz);CHKERRQ(ierr);
2493e5f4774SJed Brown     } else {                    /* Convert block-row precallocation to scalar-row */
25063562e91SJed Brown       PetscInt i,m,*sdnnz,*sonnz;
25163562e91SJed Brown       ierr = MatGetLocalSize(A,&m,PETSC_NULL);CHKERRQ(ierr);
25263562e91SJed Brown       ierr = PetscMalloc2((!!dnnz)*m*bs,PetscInt,&sdnnz,(!!onnz)*m*bs,PetscInt,&sonnz);CHKERRQ(ierr);
25363562e91SJed Brown       for (i=0; i<m*bs; i++) {
25463562e91SJed Brown         if (dnnz) sdnnz[i] = dnnz[i/bs] * bs;
25563562e91SJed Brown         if (onnz) sonnz[i] = onnz[i/bs] * bs;
25663562e91SJed Brown       }
2573e5f4774SJed Brown       ierr = MatSeqAIJSetPreallocation(A,0,dnnz?sdnnz:PETSC_NULL);CHKERRQ(ierr);
2583e5f4774SJed Brown       ierr = MatMPIAIJSetPreallocation(A,0,dnnz?sdnnz:PETSC_NULL,0,onnz?sonnz:PETSC_NULL);CHKERRQ(ierr);
25963562e91SJed Brown       ierr = PetscFree2(sdnnz,sonnz);CHKERRQ(ierr);
26063562e91SJed Brown     }
26163562e91SJed Brown   }
26263562e91SJed Brown   ierr = MatSetBlockSize(A,bs);CHKERRQ(ierr);
26363562e91SJed Brown   PetscFunctionReturn(0);
26463562e91SJed Brown }
26563562e91SJed Brown 
266273d9f13SBarry Smith /*
267eb6b5d47SBarry Smith         Merges some information from Cs header to A; the C object is then destroyed
268d0f46423SBarry Smith 
269d0f46423SBarry Smith         This is somewhat different from MatHeaderReplace() it would be nice to merge the code
270273d9f13SBarry Smith */
2714a2ae208SSatish Balay #undef __FUNCT__
272eb6b5d47SBarry Smith #define __FUNCT__ "MatHeaderMerge"
273eb6b5d47SBarry Smith PetscErrorCode MatHeaderMerge(Mat A,Mat C)
274273d9f13SBarry Smith {
275dfbe8321SBarry Smith   PetscErrorCode         ierr;
276d44834fbSBarry Smith   PetscInt               refct;
277273d9f13SBarry Smith   PetscOps               *Abops;
278273d9f13SBarry Smith   MatOps                 Aops;
279273d9f13SBarry Smith   char                   *mtype,*mname;
28030735b05SKris Buschelman   void                   *spptr;
281273d9f13SBarry Smith 
282273d9f13SBarry Smith   PetscFunctionBegin;
283273d9f13SBarry Smith   /* save the parts of A we need */
2847adad957SLisandro Dalcin   Abops = ((PetscObject)A)->bops;
285273d9f13SBarry Smith   Aops  = A->ops;
2867adad957SLisandro Dalcin   refct = ((PetscObject)A)->refct;
2875c9eb25fSBarry Smith   mtype = ((PetscObject)A)->type_name;
2885c9eb25fSBarry Smith   mname = ((PetscObject)A)->name;
28930735b05SKris Buschelman   spptr = A->spptr;
29030735b05SKris Buschelman 
2915c9eb25fSBarry Smith   /* zero these so the destroy below does not free them */
2925c9eb25fSBarry Smith   ((PetscObject)A)->type_name = 0;
2935c9eb25fSBarry Smith   ((PetscObject)A)->name      = 0;
2945c9eb25fSBarry Smith 
2957c99f97cSSatish Balay   /* free all the interior data structures from mat */
2967c99f97cSSatish Balay   ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
2977c99f97cSSatish Balay 
29830735b05SKris Buschelman   ierr = PetscFree(C->spptr);CHKERRQ(ierr);
29905b42c5fSBarry Smith 
3006bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->rmap);CHKERRQ(ierr);
3016bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->cmap);CHKERRQ(ierr);
3025c9eb25fSBarry Smith   ierr = PetscFListDestroy(&((PetscObject)A)->qlist);CHKERRQ(ierr);
3036bf464f9SBarry Smith   ierr = PetscOListDestroy(&((PetscObject)A)->olist);CHKERRQ(ierr);
304273d9f13SBarry Smith 
305273d9f13SBarry Smith   /* copy C over to A */
306273d9f13SBarry Smith   ierr  = PetscMemcpy(A,C,sizeof(struct _p_Mat));CHKERRQ(ierr);
307273d9f13SBarry Smith 
308273d9f13SBarry Smith   /* return the parts of A we saved */
3097adad957SLisandro Dalcin   ((PetscObject)A)->bops      = Abops;
310273d9f13SBarry Smith   A->ops                      = Aops;
3117adad957SLisandro Dalcin   ((PetscObject)A)->refct     = refct;
3127adad957SLisandro Dalcin   ((PetscObject)A)->type_name = mtype;
3137adad957SLisandro Dalcin   ((PetscObject)A)->name      = mname;
31430735b05SKris Buschelman   A->spptr                    = spptr;
315273d9f13SBarry Smith 
3165c9eb25fSBarry Smith   /* since these two are copied into A we do not want them destroyed in C */
3175c9eb25fSBarry Smith   ((PetscObject)C)->qlist = 0;
3185c9eb25fSBarry Smith   ((PetscObject)C)->olist = 0;
3196bf464f9SBarry Smith   ierr = PetscHeaderDestroy(&C);CHKERRQ(ierr);
320273d9f13SBarry Smith   PetscFunctionReturn(0);
321273d9f13SBarry Smith }
3228ab5b326SKris Buschelman /*
323eb6b5d47SBarry Smith         Replace A's header with that of C; the C object is then destroyed
324d0f46423SBarry Smith 
325eb6b5d47SBarry Smith         This is essentially code moved from MatDestroy()
326eb6b5d47SBarry Smith 
327eb6b5d47SBarry Smith         This is somewhat different from MatHeaderMerge() it would be nice to merge the code
3288ab5b326SKris Buschelman */
3298ab5b326SKris Buschelman #undef __FUNCT__
3308ab5b326SKris Buschelman #define __FUNCT__ "MatHeaderReplace"
3318ab5b326SKris Buschelman PetscErrorCode MatHeaderReplace(Mat A,Mat C)
3328ab5b326SKris Buschelman {
3338ab5b326SKris Buschelman   PetscErrorCode ierr;
33427b31e29SJed Brown   PetscInt refct;
3358ab5b326SKris Buschelman 
3368ab5b326SKris Buschelman   PetscFunctionBegin;
33727b31e29SJed Brown   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
33827b31e29SJed Brown   PetscValidHeaderSpecific(C,MAT_CLASSID,2);
3396d7c1e57SBarry Smith   if (A == C) PetscFunctionReturn(0);
340a7e80f87SJed Brown   PetscCheckSameComm(A,1,C,2);
341a7e80f87SJed 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);
3426d7c1e57SBarry Smith 
3438ab5b326SKris Buschelman   /* free all the interior data structures from mat */
3448ab5b326SKris Buschelman   ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
345d2c95936SBarry Smith   ierr = PetscHeaderDestroy_Private((PetscObject)A);CHKERRQ(ierr);
346c650bb5fSLisandro Dalcin   ierr = PetscFree(A->ops);CHKERRQ(ierr);
3476bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->rmap);CHKERRQ(ierr);
3486bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->cmap);CHKERRQ(ierr);
349d95db058SSatish Balay   ierr = PetscFree(A->spptr);CHKERRQ(ierr);
3508ab5b326SKris Buschelman 
3518ab5b326SKris Buschelman   /* copy C over to A */
35227b31e29SJed Brown   refct = ((PetscObject)A)->refct;
3538ab5b326SKris Buschelman   ierr = PetscMemcpy(A,C,sizeof(struct _p_Mat));CHKERRQ(ierr);
35427b31e29SJed Brown   ((PetscObject)A)->refct = refct;
3558ab5b326SKris Buschelman   ierr = PetscLogObjectDestroy((PetscObject)C);CHKERRQ(ierr);
3568ab5b326SKris Buschelman   ierr = PetscFree(C);CHKERRQ(ierr);
3578ab5b326SKris Buschelman   PetscFunctionReturn(0);
3588ab5b326SKris Buschelman }
359