xref: /petsc/src/mat/utils/gcreate.c (revision 34136279daf4c5803e26cd9ecf5a2cf0d75aa7fe)
17807a1faSBarry Smith 
2af0996ceSBarry Smith #include <petsc/private/matimpl.h>       /*I "petscmat.h"  I*/
37807a1faSBarry Smith 
446533700Sstefano_zampini PETSC_INTERN PetscErrorCode MatSetBlockSizes_Default(Mat mat,PetscInt rbs, PetscInt cbs)
546533700Sstefano_zampini {
646533700Sstefano_zampini   PetscFunctionBegin;
75c577a9aSstefano_zampini   if (!mat->preallocated) PetscFunctionReturn(0);
846533700Sstefano_zampini   if (mat->rmap->bs > 0 && mat->rmap->bs != rbs) SETERRQ2(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"Cannot change row block size %D to %D\n",mat->rmap->bs,rbs);
946533700Sstefano_zampini   if (mat->cmap->bs > 0 && mat->cmap->bs != cbs) SETERRQ2(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"Cannot change column block size %D to %D\n",mat->cmap->bs,cbs);
1046533700Sstefano_zampini   PetscFunctionReturn(0);
1146533700Sstefano_zampini }
1246533700Sstefano_zampini 
13db87b0f2SBarry Smith PETSC_INTERN PetscErrorCode MatShift_Basic(Mat Y,PetscScalar a)
147d68702bSBarry Smith {
157d68702bSBarry Smith   PetscErrorCode ierr;
167d68702bSBarry Smith   PetscInt       i,start,end;
177d68702bSBarry Smith   PetscScalar    alpha = a;
187d68702bSBarry Smith   PetscBool      prevoption;
197d68702bSBarry Smith 
207d68702bSBarry Smith   PetscFunctionBegin;
217d68702bSBarry Smith   ierr = MatGetOption(Y,MAT_NO_OFF_PROC_ENTRIES,&prevoption);CHKERRQ(ierr);
227d68702bSBarry Smith   ierr = MatSetOption(Y,MAT_NO_OFF_PROC_ENTRIES,PETSC_TRUE);CHKERRQ(ierr);
237d68702bSBarry Smith   ierr = MatGetOwnershipRange(Y,&start,&end);CHKERRQ(ierr);
247d68702bSBarry Smith   for (i=start; i<end; i++) {
257d68702bSBarry Smith     ierr = MatSetValues(Y,1,&i,1,&i,&alpha,ADD_VALUES);CHKERRQ(ierr);
267d68702bSBarry Smith   }
277d68702bSBarry Smith   ierr = MatAssemblyBegin(Y,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
287d68702bSBarry Smith   ierr = MatAssemblyEnd(Y,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
297d68702bSBarry Smith   ierr = MatSetOption(Y,MAT_NO_OFF_PROC_ENTRIES,prevoption);CHKERRQ(ierr);
307d68702bSBarry Smith   PetscFunctionReturn(0);
317d68702bSBarry Smith }
327d68702bSBarry Smith 
3305869f15SSatish Balay /*@
3469dd0797SLois Curfman McInnes    MatCreate - Creates a matrix where the type is determined
357e5f4302SBarry Smith    from either a call to MatSetType() or from the options database
367e5f4302SBarry Smith    with a call to MatSetFromOptions(). The default matrix type is
3769b1f4b7SBarry Smith    AIJ, using the routines MatCreateSeqAIJ() or MatCreateAIJ()
387e5f4302SBarry Smith    if you do not set a type in the options database. If you never
397e5f4302SBarry Smith    call MatSetType() or MatSetFromOptions() it will generate an
40f8ab6608SSatish Balay    error when you try to use the matrix.
4183e1b59cSLois Curfman McInnes 
42cb13003dSBarry Smith    Collective on MPI_Comm
43cb13003dSBarry Smith 
44f69a0ea3SMatthew Knepley    Input Parameter:
45f69a0ea3SMatthew Knepley .  comm - MPI communicator
467807a1faSBarry Smith 
477807a1faSBarry Smith    Output Parameter:
48dc401e71SLois Curfman McInnes .  A - the matrix
49e0b365e2SLois Curfman McInnes 
50273d9f13SBarry Smith    Options Database Keys:
51273d9f13SBarry Smith +    -mat_type seqaij   - AIJ type, uses MatCreateSeqAIJ()
5269b1f4b7SBarry Smith .    -mat_type mpiaij   - AIJ type, uses MatCreateAIJ()
53273d9f13SBarry Smith .    -mat_type seqdense - dense type, uses MatCreateSeqDense()
5469b1f4b7SBarry Smith .    -mat_type mpidense - dense type, uses MatCreateDense()
55273d9f13SBarry Smith .    -mat_type seqbaij  - block AIJ type, uses MatCreateSeqBAIJ()
5669b1f4b7SBarry Smith -    -mat_type mpibaij  - block AIJ type, uses MatCreateBAIJ()
57e0b365e2SLois Curfman McInnes 
5883e1b59cSLois Curfman McInnes    Even More Options Database Keys:
5983e1b59cSLois Curfman McInnes    See the manpages for particular formats (e.g., MatCreateSeqAIJ())
6083e1b59cSLois Curfman McInnes    for additional format-specific options.
61e0b365e2SLois Curfman McInnes 
62bd9ce289SLois Curfman McInnes    Notes:
63ec6e0d80SSatish Balay 
64273d9f13SBarry Smith    Level: beginner
65273d9f13SBarry Smith 
66a2fc510eSBarry Smith    User manual sections:
67a2fc510eSBarry Smith +   sec_matcreate
68a2fc510eSBarry Smith -   chapter_matrices
69a2fc510eSBarry Smith 
70273d9f13SBarry Smith .keywords: matrix, create
71273d9f13SBarry Smith 
7269b1f4b7SBarry Smith .seealso: MatCreateSeqAIJ(), MatCreateAIJ(),
7369b1f4b7SBarry Smith           MatCreateSeqDense(), MatCreateDense(),
7469b1f4b7SBarry Smith           MatCreateSeqBAIJ(), MatCreateBAIJ(),
7569b1f4b7SBarry Smith           MatCreateSeqSBAIJ(), MatCreateSBAIJ(),
76273d9f13SBarry Smith           MatConvert()
77273d9f13SBarry Smith @*/
787087cfbeSBarry Smith PetscErrorCode  MatCreate(MPI_Comm comm,Mat *A)
79273d9f13SBarry Smith {
80273d9f13SBarry Smith   Mat            B;
81dfbe8321SBarry Smith   PetscErrorCode ierr;
82273d9f13SBarry Smith 
83273d9f13SBarry Smith   PetscFunctionBegin;
84f69a0ea3SMatthew Knepley   PetscValidPointer(A,2);
8597f1f81fSBarry Smith 
860298fd71SBarry Smith   *A = NULL;
87607a6623SBarry Smith   ierr = MatInitializePackage();CHKERRQ(ierr);
888ba1e511SMatthew Knepley 
8973107ff1SLisandro Dalcin   ierr = PetscHeaderCreate(B,MAT_CLASSID,"Mat","Matrix","Mat",comm,MatDestroy,MatView);CHKERRQ(ierr);
9026283091SBarry Smith   ierr = PetscLayoutCreate(comm,&B->rmap);CHKERRQ(ierr);
9126283091SBarry Smith   ierr = PetscLayoutCreate(comm,&B->cmap);CHKERRQ(ierr);
92*34136279SStefano Zampini   ierr = PetscStrallocpy(VECSTANDARD,&B->defaultvectype);CHKERRQ(ierr);
9326fbe8dcSKarl Rupp 
9494342113SStefano Zampini   B->congruentlayouts = PETSC_DECIDE;
95273d9f13SBarry Smith   B->preallocated     = PETSC_FALSE;
96273d9f13SBarry Smith   *A                  = B;
97273d9f13SBarry Smith   PetscFunctionReturn(0);
98273d9f13SBarry Smith }
99273d9f13SBarry Smith 
100422a814eSBarry Smith /*@
10184d44b13SHong Zhang    MatSetErrorIfFailure - Causes Mat to generate an error, for example a zero pivot, is detected.
102422a814eSBarry Smith 
103422a814eSBarry Smith    Logically Collective on Mat
104422a814eSBarry Smith 
105422a814eSBarry Smith    Input Parameters:
106422a814eSBarry Smith +  mat -  matrix obtained from MatCreate()
107422a814eSBarry Smith -  flg - PETSC_TRUE indicates you want the error generated
108422a814eSBarry Smith 
109422a814eSBarry Smith    Level: advanced
110422a814eSBarry Smith 
111422a814eSBarry Smith .keywords: Mat, set, initial guess, nonzero
112422a814eSBarry Smith 
113422a814eSBarry Smith .seealso: PCSetErrorIfFailure()
114422a814eSBarry Smith @*/
11584d44b13SHong Zhang PetscErrorCode  MatSetErrorIfFailure(Mat mat,PetscBool flg)
116422a814eSBarry Smith {
117422a814eSBarry Smith   PetscFunctionBegin;
118422a814eSBarry Smith   PetscValidHeaderSpecific(mat,MAT_CLASSID,1);
119422a814eSBarry Smith   PetscValidLogicalCollectiveBool(mat,flg,2);
12084d44b13SHong Zhang   mat->erroriffailure = flg;
121422a814eSBarry Smith   PetscFunctionReturn(0);
122422a814eSBarry Smith }
123422a814eSBarry Smith 
124f69a0ea3SMatthew Knepley /*@
125f69a0ea3SMatthew Knepley   MatSetSizes - Sets the local and global sizes, and checks to determine compatibility
126f69a0ea3SMatthew Knepley 
127f69a0ea3SMatthew Knepley   Collective on Mat
128f69a0ea3SMatthew Knepley 
129f69a0ea3SMatthew Knepley   Input Parameters:
130f69a0ea3SMatthew Knepley +  A - the matrix
131f69a0ea3SMatthew Knepley .  m - number of local rows (or PETSC_DECIDE)
132f69a0ea3SMatthew Knepley .  n - number of local columns (or PETSC_DECIDE)
133f69a0ea3SMatthew Knepley .  M - number of global rows (or PETSC_DETERMINE)
134f69a0ea3SMatthew Knepley -  N - number of global columns (or PETSC_DETERMINE)
135f69a0ea3SMatthew Knepley 
136f69a0ea3SMatthew Knepley    Notes:
137f69a0ea3SMatthew Knepley    m (n) and M (N) cannot be both PETSC_DECIDE
138f69a0ea3SMatthew Knepley    If one processor calls this with M (N) of PETSC_DECIDE then all processors must, otherwise the program will hang.
139f69a0ea3SMatthew Knepley 
140f69a0ea3SMatthew Knepley    If PETSC_DECIDE is not used for the arguments 'm' and 'n', then the
141f69a0ea3SMatthew Knepley    user must ensure that they are chosen to be compatible with the
142f69a0ea3SMatthew Knepley    vectors. To do this, one first considers the matrix-vector product
143f69a0ea3SMatthew Knepley    'y = A x'. The 'm' that is used in the above routine must match the
144f69a0ea3SMatthew Knepley    local size used in the vector creation routine VecCreateMPI() for 'y'.
145f69a0ea3SMatthew Knepley    Likewise, the 'n' used must match that used as the local size in
146f69a0ea3SMatthew Knepley    VecCreateMPI() for 'x'.
147f69a0ea3SMatthew Knepley 
148f73d5cc4SBarry Smith    You cannot change the sizes once they have been set.
149f73d5cc4SBarry Smith 
150f73d5cc4SBarry Smith    The sizes must be set before MatSetUp() or MatXXXSetPreallocation() is called.
151f73d5cc4SBarry Smith 
152f69a0ea3SMatthew Knepley   Level: beginner
153f69a0ea3SMatthew Knepley 
154f69a0ea3SMatthew Knepley .seealso: MatGetSize(), PetscSplitOwnership()
155f69a0ea3SMatthew Knepley @*/
1567087cfbeSBarry Smith PetscErrorCode  MatSetSizes(Mat A, PetscInt m, PetscInt n, PetscInt M, PetscInt N)
157f69a0ea3SMatthew Knepley {
158f69a0ea3SMatthew Knepley   PetscFunctionBegin;
1590700a824SBarry Smith   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
160b28e6c9fSJed Brown   if (M > 0) PetscValidLogicalCollectiveInt(A,M,4);
161b28e6c9fSJed Brown   if (N > 0) PetscValidLogicalCollectiveInt(A,N,5);
162e32f2f54SBarry 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);
163e32f2f54SBarry 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);
16459cb773eSBarry Smith   if ((A->rmap->n >= 0 && A->rmap->N >= 0) && (A->rmap->n != m || (M > 0 && 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);
16559cb773eSBarry Smith   if ((A->cmap->n >= 0 && A->cmap->N >= 0) && (A->cmap->n != n || (N > 0 && 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);
166d0f46423SBarry Smith   A->rmap->n = m;
167d0f46423SBarry Smith   A->cmap->n = n;
16859cb773eSBarry Smith   A->rmap->N = M > -1 ? M : A->rmap->N;
16959cb773eSBarry Smith   A->cmap->N = N > -1 ? N : A->cmap->N;
170f69a0ea3SMatthew Knepley   PetscFunctionReturn(0);
171f69a0ea3SMatthew Knepley }
172f69a0ea3SMatthew Knepley 
17305869f15SSatish Balay /*@
174273d9f13SBarry Smith    MatSetFromOptions - Creates a matrix where the type is determined
175273d9f13SBarry Smith    from the options database. Generates a parallel MPI matrix if the
176273d9f13SBarry Smith    communicator has more than one processor.  The default matrix type is
17769b1f4b7SBarry Smith    AIJ, using the routines MatCreateSeqAIJ() and MatCreateAIJ() if
1787e5f4302SBarry Smith    you do not select a type in the options database.
179273d9f13SBarry Smith 
180273d9f13SBarry Smith    Collective on Mat
181273d9f13SBarry Smith 
182273d9f13SBarry Smith    Input Parameter:
183273d9f13SBarry Smith .  A - the matrix
184273d9f13SBarry Smith 
185273d9f13SBarry Smith    Options Database Keys:
186273d9f13SBarry Smith +    -mat_type seqaij   - AIJ type, uses MatCreateSeqAIJ()
18769b1f4b7SBarry Smith .    -mat_type mpiaij   - AIJ type, uses MatCreateAIJ()
188273d9f13SBarry Smith .    -mat_type seqdense - dense type, uses MatCreateSeqDense()
18969b1f4b7SBarry Smith .    -mat_type mpidense - dense type, uses MatCreateDense()
190273d9f13SBarry Smith .    -mat_type seqbaij  - block AIJ type, uses MatCreateSeqBAIJ()
19169b1f4b7SBarry Smith -    -mat_type mpibaij  - block AIJ type, uses MatCreateBAIJ()
192273d9f13SBarry Smith 
193273d9f13SBarry Smith    Even More Options Database Keys:
194273d9f13SBarry Smith    See the manpages for particular formats (e.g., MatCreateSeqAIJ())
195273d9f13SBarry Smith    for additional format-specific options.
196bd9ce289SLois Curfman McInnes 
1971d69843bSLois Curfman McInnes    Level: beginner
1981d69843bSLois Curfman McInnes 
199dc401e71SLois Curfman McInnes .keywords: matrix, create
200e0b365e2SLois Curfman McInnes 
20169b1f4b7SBarry Smith .seealso: MatCreateSeqAIJ((), MatCreateAIJ(),
20269b1f4b7SBarry Smith           MatCreateSeqDense(), MatCreateDense(),
20369b1f4b7SBarry Smith           MatCreateSeqBAIJ(), MatCreateBAIJ(),
20469b1f4b7SBarry Smith           MatCreateSeqSBAIJ(), MatCreateSBAIJ(),
205273d9f13SBarry Smith           MatConvert()
2067807a1faSBarry Smith @*/
2077087cfbeSBarry Smith PetscErrorCode  MatSetFromOptions(Mat B)
2087807a1faSBarry Smith {
209dfbe8321SBarry Smith   PetscErrorCode ierr;
210f3be49caSLisandro Dalcin   const char     *deft = MATAIJ;
211f3be49caSLisandro Dalcin   char           type[256];
21269df5c0cSJed Brown   PetscBool      flg,set;
213dbb450caSBarry Smith 
2143a40ed3dSBarry Smith   PetscFunctionBegin;
2150700a824SBarry Smith   PetscValidHeaderSpecific(B,MAT_CLASSID,1);
216f3be49caSLisandro Dalcin 
2173194b578SJed Brown   ierr = PetscObjectOptionsBegin((PetscObject)B);CHKERRQ(ierr);
218535b19f3SBarry Smith 
219535b19f3SBarry Smith   if (B->rmap->bs < 0) {
220535b19f3SBarry Smith     PetscInt newbs = -1;
221535b19f3SBarry Smith     ierr = PetscOptionsInt("-mat_block_size","Set the blocksize used to store the matrix","MatSetBlockSize",newbs,&newbs,&flg);CHKERRQ(ierr);
222535b19f3SBarry Smith     if (flg) {
223535b19f3SBarry Smith       ierr = PetscLayoutSetBlockSize(B->rmap,newbs);CHKERRQ(ierr);
224535b19f3SBarry Smith       ierr = PetscLayoutSetBlockSize(B->cmap,newbs);CHKERRQ(ierr);
225535b19f3SBarry Smith     }
226535b19f3SBarry Smith   }
227535b19f3SBarry Smith 
228a264d7a6SBarry Smith   ierr = PetscOptionsFList("-mat_type","Matrix type","MatSetType",MatList,deft,type,256,&flg);CHKERRQ(ierr);
229273d9f13SBarry Smith   if (flg) {
230f3be49caSLisandro Dalcin     ierr = MatSetType(B,type);CHKERRQ(ierr);
231f3be49caSLisandro Dalcin   } else if (!((PetscObject)B)->type_name) {
232f3be49caSLisandro Dalcin     ierr = MatSetType(B,deft);CHKERRQ(ierr);
233273d9f13SBarry Smith   }
234f3be49caSLisandro Dalcin 
235840d65ccSBarry Smith   ierr = PetscOptionsName("-mat_is_symmetric","Checks if mat is symmetric on MatAssemblyEnd()","MatIsSymmetric",&B->checksymmetryonassembly);CHKERRQ(ierr);
23694ae4db5SBarry Smith   ierr = PetscOptionsReal("-mat_is_symmetric","Checks if mat is symmetric on MatAssemblyEnd()","MatIsSymmetric",B->checksymmetrytol,&B->checksymmetrytol,NULL);CHKERRQ(ierr);
23794ae4db5SBarry Smith   ierr = PetscOptionsBool("-mat_null_space_test","Checks if provided null space is correct in MatAssemblyEnd()","MatSetNullSpaceTest",B->checknullspaceonassembly,&B->checknullspaceonassembly,NULL);CHKERRQ(ierr);
238840d65ccSBarry Smith 
239f3be49caSLisandro Dalcin   if (B->ops->setfromoptions) {
240e55864a3SBarry Smith     ierr = (*B->ops->setfromoptions)(PetscOptionsObject,B);CHKERRQ(ierr);
241593c1905SSatish Balay   }
242f3be49caSLisandro Dalcin 
24369df5c0cSJed Brown   flg  = PETSC_FALSE;
24469df5c0cSJed 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);
24569df5c0cSJed Brown   if (set) {ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,flg);CHKERRQ(ierr);}
24669df5c0cSJed Brown   flg  = PETSC_FALSE;
24769df5c0cSJed 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);
24869df5c0cSJed Brown   if (set) {ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,flg);CHKERRQ(ierr);}
24969df5c0cSJed Brown 
2505d973c19SBarry Smith   /* process any options handlers added with PetscObjectAddOptionsHandler() */
2510633abcbSJed Brown   ierr = PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)B);CHKERRQ(ierr);
252f3be49caSLisandro Dalcin   ierr = PetscOptionsEnd();CHKERRQ(ierr);
2533a40ed3dSBarry Smith   PetscFunctionReturn(0);
2547807a1faSBarry Smith }
2557807a1faSBarry Smith 
256987010e7SBarry Smith /*@C
257e8bd9bafSStefano Zampini    MatXAIJSetPreallocation - set preallocation for serial and parallel AIJ, BAIJ, and SBAIJ matrices and their unassembled versions.
25863562e91SJed Brown 
25963562e91SJed Brown    Collective on Mat
26063562e91SJed Brown 
26163562e91SJed Brown    Input Arguments:
26263562e91SJed Brown +  A - matrix being preallocated
26363562e91SJed Brown .  bs - block size
2643e5f4774SJed Brown .  dnnz - number of nonzero blocks per block row of diagonal part of parallel matrix
2653e5f4774SJed Brown .  onnz - number of nonzero blocks per block row of off-diagonal part of parallel matrix
2663e5f4774SJed Brown .  dnnzu - number of nonzero blocks per block row of upper-triangular part of diagonal part of parallel matrix
2673e5f4774SJed Brown -  onnzu - number of nonzero blocks per block row of upper-triangular part of off-diagonal part of parallel matrix
26863562e91SJed Brown 
26963562e91SJed Brown    Level: beginner
27063562e91SJed Brown 
271ab978733SBarry Smith .seealso: MatSeqAIJSetPreallocation(), MatMPIAIJSetPreallocation(), MatSeqBAIJSetPreallocation(), MatMPIBAIJSetPreallocation(), MatSeqSBAIJSetPreallocation(), MatMPISBAIJSetPreallocation(),
272ab978733SBarry Smith           PetscSplitOwnership()
27363562e91SJed Brown @*/
2744cce697cSJed Brown PetscErrorCode MatXAIJSetPreallocation(Mat A,PetscInt bs,const PetscInt dnnz[],const PetscInt onnz[],const PetscInt dnnzu[],const PetscInt onnzu[])
27563562e91SJed Brown {
27663562e91SJed Brown   PetscErrorCode ierr;
27763562e91SJed Brown   void           (*aij)(void);
278e8bd9bafSStefano Zampini   void           (*is)(void);
27963562e91SJed Brown 
28063562e91SJed Brown   PetscFunctionBegin;
281dec54756SJed Brown   ierr = MatSetBlockSize(A,bs);CHKERRQ(ierr);
28269bbac97SJed Brown   ierr = MatGetBlockSize(A,&bs);CHKERRQ(ierr);
283dec54756SJed Brown   ierr = PetscLayoutSetUp(A->rmap);CHKERRQ(ierr);
284dec54756SJed Brown   ierr = PetscLayoutSetUp(A->cmap);CHKERRQ(ierr);
2853e5f4774SJed Brown   ierr = MatSeqBAIJSetPreallocation(A,bs,0,dnnz);CHKERRQ(ierr);
2863e5f4774SJed Brown   ierr = MatMPIBAIJSetPreallocation(A,bs,0,dnnz,0,onnz);CHKERRQ(ierr);
2873e5f4774SJed Brown   ierr = MatSeqSBAIJSetPreallocation(A,bs,0,dnnzu);CHKERRQ(ierr);
2883e5f4774SJed Brown   ierr = MatMPISBAIJSetPreallocation(A,bs,0,dnnzu,0,onnzu);CHKERRQ(ierr);
28963562e91SJed Brown   /*
290e8bd9bafSStefano Zampini     In general, we have to do extra work to preallocate for scalar (AIJ) or unassembled (IS) matrices so we check whether it will do any
29163562e91SJed Brown     good before going on with it.
29263562e91SJed Brown   */
29363562e91SJed Brown   ierr = PetscObjectQueryFunction((PetscObject)A,"MatMPIAIJSetPreallocation_C",&aij);CHKERRQ(ierr);
294e8bd9bafSStefano Zampini   ierr = PetscObjectQueryFunction((PetscObject)A,"MatISSetPreallocation_C",&is);CHKERRQ(ierr);
295e8bd9bafSStefano Zampini   if (!aij && !is) {
29663562e91SJed Brown     ierr = PetscObjectQueryFunction((PetscObject)A,"MatSeqAIJSetPreallocation_C",&aij);CHKERRQ(ierr);
29763562e91SJed Brown   }
298e8bd9bafSStefano Zampini   if (aij || is) {
29963562e91SJed Brown     if (bs == 1) {
3003e5f4774SJed Brown       ierr = MatSeqAIJSetPreallocation(A,0,dnnz);CHKERRQ(ierr);
3013e5f4774SJed Brown       ierr = MatMPIAIJSetPreallocation(A,0,dnnz,0,onnz);CHKERRQ(ierr);
302e8bd9bafSStefano Zampini       ierr = MatISSetPreallocation(A,0,dnnz,0,onnz);CHKERRQ(ierr);
3033e5f4774SJed Brown     } else {                    /* Convert block-row precallocation to scalar-row */
30463562e91SJed Brown       PetscInt i,m,*sdnnz,*sonnz;
3050298fd71SBarry Smith       ierr = MatGetLocalSize(A,&m,NULL);CHKERRQ(ierr);
306dcca6d9dSJed Brown       ierr = PetscMalloc2((!!dnnz)*m,&sdnnz,(!!onnz)*m,&sonnz);CHKERRQ(ierr);
307dec54756SJed Brown       for (i=0; i<m; i++) {
30863562e91SJed Brown         if (dnnz) sdnnz[i] = dnnz[i/bs] * bs;
30963562e91SJed Brown         if (onnz) sonnz[i] = onnz[i/bs] * bs;
31063562e91SJed Brown       }
3110298fd71SBarry Smith       ierr = MatSeqAIJSetPreallocation(A,0,dnnz ? sdnnz : NULL);CHKERRQ(ierr);
3120298fd71SBarry Smith       ierr = MatMPIAIJSetPreallocation(A,0,dnnz ? sdnnz : NULL,0,onnz ? sonnz : NULL);CHKERRQ(ierr);
313e8bd9bafSStefano Zampini       ierr = MatISSetPreallocation(A,0,dnnz ? sdnnz : NULL,0,onnz ? sonnz : NULL);CHKERRQ(ierr);
31463562e91SJed Brown       ierr = PetscFree2(sdnnz,sonnz);CHKERRQ(ierr);
31563562e91SJed Brown     }
31663562e91SJed Brown   }
31763562e91SJed Brown   PetscFunctionReturn(0);
31863562e91SJed Brown }
31963562e91SJed Brown 
320273d9f13SBarry Smith /*
321eb6b5d47SBarry Smith         Merges some information from Cs header to A; the C object is then destroyed
322d0f46423SBarry Smith 
323d0f46423SBarry Smith         This is somewhat different from MatHeaderReplace() it would be nice to merge the code
324273d9f13SBarry Smith */
32528be2f97SBarry Smith PetscErrorCode MatHeaderMerge(Mat A,Mat *C)
326273d9f13SBarry Smith {
327dfbe8321SBarry Smith   PetscErrorCode ierr;
328d44834fbSBarry Smith   PetscInt       refct;
32973107ff1SLisandro Dalcin   PetscOps       Abops;
33073107ff1SLisandro Dalcin   struct _MatOps Aops;
331273d9f13SBarry Smith   char           *mtype,*mname;
332273d9f13SBarry Smith 
333273d9f13SBarry Smith   PetscFunctionBegin;
334273d9f13SBarry Smith   /* save the parts of A we need */
33573107ff1SLisandro Dalcin   Abops = ((PetscObject)A)->bops[0];
33673107ff1SLisandro Dalcin   Aops  = A->ops[0];
3377adad957SLisandro Dalcin   refct = ((PetscObject)A)->refct;
3385c9eb25fSBarry Smith   mtype = ((PetscObject)A)->type_name;
3395c9eb25fSBarry Smith   mname = ((PetscObject)A)->name;
34030735b05SKris Buschelman 
3415c9eb25fSBarry Smith   /* zero these so the destroy below does not free them */
3425c9eb25fSBarry Smith   ((PetscObject)A)->type_name = 0;
3435c9eb25fSBarry Smith   ((PetscObject)A)->name      = 0;
3445c9eb25fSBarry Smith 
3457c99f97cSSatish Balay   /* free all the interior data structures from mat */
3467c99f97cSSatish Balay   ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
3477c99f97cSSatish Balay 
348*34136279SStefano Zampini   ierr = PetscFree(A->defaultvectype);CHKERRQ(ierr);
3496bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->rmap);CHKERRQ(ierr);
3506bf464f9SBarry Smith   ierr = PetscLayoutDestroy(&A->cmap);CHKERRQ(ierr);
351140e18c1SBarry Smith   ierr = PetscFunctionListDestroy(&((PetscObject)A)->qlist);CHKERRQ(ierr);
352140e18c1SBarry Smith   ierr = PetscObjectListDestroy(&((PetscObject)A)->olist);CHKERRQ(ierr);
353273d9f13SBarry Smith 
354273d9f13SBarry Smith   /* copy C over to A */
35528be2f97SBarry Smith   ierr = PetscMemcpy(A,*C,sizeof(struct _p_Mat));CHKERRQ(ierr);
356273d9f13SBarry Smith 
357273d9f13SBarry Smith   /* return the parts of A we saved */
35873107ff1SLisandro Dalcin   ((PetscObject)A)->bops[0]   = Abops;
35973107ff1SLisandro Dalcin   A->ops[0]                   = Aops;
3607adad957SLisandro Dalcin   ((PetscObject)A)->refct     = refct;
3617adad957SLisandro Dalcin   ((PetscObject)A)->type_name = mtype;
3627adad957SLisandro Dalcin   ((PetscObject)A)->name      = mname;
363273d9f13SBarry Smith 
3645c9eb25fSBarry Smith   /* since these two are copied into A we do not want them destroyed in C */
36528be2f97SBarry Smith   ((PetscObject)*C)->qlist = 0;
36628be2f97SBarry Smith   ((PetscObject)*C)->olist = 0;
36726fbe8dcSKarl Rupp 
36828be2f97SBarry Smith   ierr = PetscHeaderDestroy(C);CHKERRQ(ierr);
369273d9f13SBarry Smith   PetscFunctionReturn(0);
370273d9f13SBarry Smith }
3718ab5b326SKris Buschelman /*
372eb6b5d47SBarry Smith         Replace A's header with that of C; the C object is then destroyed
373d0f46423SBarry Smith 
374eb6b5d47SBarry Smith         This is essentially code moved from MatDestroy()
375eb6b5d47SBarry Smith 
376eb6b5d47SBarry Smith         This is somewhat different from MatHeaderMerge() it would be nice to merge the code
377b30237c6SBarry Smith 
378b30237c6SBarry Smith         Used in DM hence is declared PETSC_EXTERN
3798ab5b326SKris Buschelman */
38028be2f97SBarry Smith PETSC_EXTERN PetscErrorCode MatHeaderReplace(Mat A,Mat *C)
3818ab5b326SKris Buschelman {
3828ab5b326SKris Buschelman   PetscErrorCode   ierr;
38327b31e29SJed Brown   PetscInt         refct;
384fefd9316SJose E. Roman   PetscObjectState state;
38528be2f97SBarry Smith   struct _p_Mat    buffer;
3868ab5b326SKris Buschelman 
3878ab5b326SKris Buschelman   PetscFunctionBegin;
38827b31e29SJed Brown   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
38928be2f97SBarry Smith   PetscValidHeaderSpecific(*C,MAT_CLASSID,2);
39028be2f97SBarry Smith   if (A == *C) PetscFunctionReturn(0);
39128be2f97SBarry Smith   PetscCheckSameComm(A,1,*C,2);
39228be2f97SBarry Smith   if (((PetscObject)*C)->refct != 1) SETERRQ1(PetscObjectComm((PetscObject)C),PETSC_ERR_ARG_WRONGSTATE,"Object C has refct %D > 1, would leave hanging reference",((PetscObject)*C)->refct);
3936d7c1e57SBarry Smith 
39428be2f97SBarry Smith   /* swap C and A */
39527b31e29SJed Brown   refct = ((PetscObject)A)->refct;
396fefd9316SJose E. Roman   state = ((PetscObject)A)->state;
39728be2f97SBarry Smith   ierr  = PetscMemcpy(&buffer,A,sizeof(struct _p_Mat));CHKERRQ(ierr);
39828be2f97SBarry Smith   ierr  = PetscMemcpy(A,*C,sizeof(struct _p_Mat));CHKERRQ(ierr);
39928be2f97SBarry Smith   ierr  = PetscMemcpy(*C,&buffer,sizeof(struct _p_Mat));CHKERRQ(ierr);
40027b31e29SJed Brown   ((PetscObject)A)->refct = refct;
401fefd9316SJose E. Roman   ((PetscObject)A)->state = state + 1;
40226fbe8dcSKarl Rupp 
403c32d4117SBarry Smith   ((PetscObject)*C)->refct = 1;
40428be2f97SBarry Smith   ierr = MatDestroy(C);CHKERRQ(ierr);
4058ab5b326SKris Buschelman   PetscFunctionReturn(0);
4068ab5b326SKris Buschelman }
407