xref: /petsc/src/mat/impls/scatter/mscatter.c (revision 283d8c0488b108170dfb25ce26dc69cbdd3bfdfa) 
12a6744ebSBarry Smith /*
22a6744ebSBarry Smith    This provides a matrix that applies a VecScatter to a vector.
32a6744ebSBarry Smith */
42a6744ebSBarry Smith 
5af0996ceSBarry Smith #include <petsc/private/matimpl.h> /*I "petscmat.h" I*/
6af0996ceSBarry Smith #include <petsc/private/vecimpl.h>
72a6744ebSBarry Smith 
82a6744ebSBarry Smith typedef struct {
92a6744ebSBarry Smith   VecScatter scatter;
102a6744ebSBarry Smith } Mat_Scatter;
112a6744ebSBarry Smith 
122a6744ebSBarry Smith /*@
1311a5261eSBarry Smith   MatScatterGetVecScatter - Returns the user-provided scatter set with `MatScatterSetVecScatter()` in a `MATSCATTER` matrix
142a6744ebSBarry Smith 
152ef1f0ffSBarry Smith   Logically Collective
162a6744ebSBarry Smith 
172a6744ebSBarry Smith   Input Parameter:
1811a5261eSBarry Smith . mat - the matrix, should have been created with MatCreateScatter() or have type `MATSCATTER`
192a6744ebSBarry Smith 
202a6744ebSBarry Smith   Output Parameter:
212a6744ebSBarry Smith . scatter - the scatter context
222a6744ebSBarry Smith 
232a6744ebSBarry Smith   Level: intermediate
242a6744ebSBarry Smith 
25fe59aa6dSJacob Faibussowitsch .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, `MatCreateScatter()`, `MatScatterSetVecScatter()`
262a6744ebSBarry Smith @*/
27d71ae5a4SJacob Faibussowitsch PetscErrorCode MatScatterGetVecScatter(Mat mat, VecScatter *scatter)
28d71ae5a4SJacob Faibussowitsch {
292a6744ebSBarry Smith   Mat_Scatter *mscatter;
302a6744ebSBarry Smith 
312a6744ebSBarry Smith   PetscFunctionBegin;
320700a824SBarry Smith   PetscValidHeaderSpecific(mat, MAT_CLASSID, 1);
334f572ea9SToby Isaac   PetscAssertPointer(scatter, 2);
342a6744ebSBarry Smith   mscatter = (Mat_Scatter *)mat->data;
352a6744ebSBarry Smith   *scatter = mscatter->scatter;
363ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
372a6744ebSBarry Smith }
382a6744ebSBarry Smith 
3966976f2fSJacob Faibussowitsch static PetscErrorCode MatDestroy_Scatter(Mat mat)
40d71ae5a4SJacob Faibussowitsch {
412a6744ebSBarry Smith   Mat_Scatter *scatter = (Mat_Scatter *)mat->data;
422a6744ebSBarry Smith 
432a6744ebSBarry Smith   PetscFunctionBegin;
449566063dSJacob Faibussowitsch   PetscCall(VecScatterDestroy(&scatter->scatter));
459566063dSJacob Faibussowitsch   PetscCall(PetscFree(mat->data));
463ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
472a6744ebSBarry Smith }
482a6744ebSBarry Smith 
4966976f2fSJacob Faibussowitsch static PetscErrorCode MatMult_Scatter(Mat A, Vec x, Vec y)
50d71ae5a4SJacob Faibussowitsch {
512a6744ebSBarry Smith   Mat_Scatter *scatter = (Mat_Scatter *)A->data;
522a6744ebSBarry Smith 
532a6744ebSBarry Smith   PetscFunctionBegin;
5428b400f6SJacob Faibussowitsch   PetscCheck(scatter->scatter, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "Need to first call MatScatterSetScatter()");
559566063dSJacob Faibussowitsch   PetscCall(VecZeroEntries(y));
569566063dSJacob Faibussowitsch   PetscCall(VecScatterBegin(scatter->scatter, x, y, ADD_VALUES, SCATTER_FORWARD));
579566063dSJacob Faibussowitsch   PetscCall(VecScatterEnd(scatter->scatter, x, y, ADD_VALUES, SCATTER_FORWARD));
583ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
592a6744ebSBarry Smith }
602a6744ebSBarry Smith 
6166976f2fSJacob Faibussowitsch static PetscErrorCode MatMultAdd_Scatter(Mat A, Vec x, Vec y, Vec z)
62d71ae5a4SJacob Faibussowitsch {
632a6744ebSBarry Smith   Mat_Scatter *scatter = (Mat_Scatter *)A->data;
642a6744ebSBarry Smith 
652a6744ebSBarry Smith   PetscFunctionBegin;
6628b400f6SJacob Faibussowitsch   PetscCheck(scatter->scatter, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "Need to first call MatScatterSetScatter()");
679566063dSJacob Faibussowitsch   if (z != y) PetscCall(VecCopy(y, z));
689566063dSJacob Faibussowitsch   PetscCall(VecScatterBegin(scatter->scatter, x, z, ADD_VALUES, SCATTER_FORWARD));
699566063dSJacob Faibussowitsch   PetscCall(VecScatterEnd(scatter->scatter, x, z, ADD_VALUES, SCATTER_FORWARD));
703ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
712a6744ebSBarry Smith }
722a6744ebSBarry Smith 
7366976f2fSJacob Faibussowitsch static PetscErrorCode MatMultTranspose_Scatter(Mat A, Vec x, Vec y)
74d71ae5a4SJacob Faibussowitsch {
752a6744ebSBarry Smith   Mat_Scatter *scatter = (Mat_Scatter *)A->data;
762a6744ebSBarry Smith 
772a6744ebSBarry Smith   PetscFunctionBegin;
7828b400f6SJacob Faibussowitsch   PetscCheck(scatter->scatter, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "Need to first call MatScatterSetScatter()");
799566063dSJacob Faibussowitsch   PetscCall(VecZeroEntries(y));
809566063dSJacob Faibussowitsch   PetscCall(VecScatterBegin(scatter->scatter, x, y, ADD_VALUES, SCATTER_REVERSE));
819566063dSJacob Faibussowitsch   PetscCall(VecScatterEnd(scatter->scatter, x, y, ADD_VALUES, SCATTER_REVERSE));
823ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
832a6744ebSBarry Smith }
842a6744ebSBarry Smith 
8566976f2fSJacob Faibussowitsch static PetscErrorCode MatMultTransposeAdd_Scatter(Mat A, Vec x, Vec y, Vec z)
86d71ae5a4SJacob Faibussowitsch {
872a6744ebSBarry Smith   Mat_Scatter *scatter = (Mat_Scatter *)A->data;
882a6744ebSBarry Smith 
892a6744ebSBarry Smith   PetscFunctionBegin;
9028b400f6SJacob Faibussowitsch   PetscCheck(scatter->scatter, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "Need to first call MatScatterSetScatter()");
919566063dSJacob Faibussowitsch   if (z != y) PetscCall(VecCopy(y, z));
929566063dSJacob Faibussowitsch   PetscCall(VecScatterBegin(scatter->scatter, x, z, ADD_VALUES, SCATTER_REVERSE));
939566063dSJacob Faibussowitsch   PetscCall(VecScatterEnd(scatter->scatter, x, z, ADD_VALUES, SCATTER_REVERSE));
943ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
952a6744ebSBarry Smith }
962a6744ebSBarry Smith 
97f4259b30SLisandro Dalcin static struct _MatOps MatOps_Values = {NULL,
98f4259b30SLisandro Dalcin                                        NULL,
99f4259b30SLisandro Dalcin                                        NULL,
1002a6744ebSBarry Smith                                        MatMult_Scatter,
1012a6744ebSBarry Smith                                        /*  4*/ MatMultAdd_Scatter,
1022a6744ebSBarry Smith                                        MatMultTranspose_Scatter,
1032a6744ebSBarry Smith                                        MatMultTransposeAdd_Scatter,
104f4259b30SLisandro Dalcin                                        NULL,
105f4259b30SLisandro Dalcin                                        NULL,
106f4259b30SLisandro Dalcin                                        NULL,
107f4259b30SLisandro Dalcin                                        /* 10*/ NULL,
108f4259b30SLisandro Dalcin                                        NULL,
109f4259b30SLisandro Dalcin                                        NULL,
110f4259b30SLisandro Dalcin                                        NULL,
111f4259b30SLisandro Dalcin                                        NULL,
112f4259b30SLisandro Dalcin                                        /* 15*/ NULL,
113f4259b30SLisandro Dalcin                                        NULL,
114f4259b30SLisandro Dalcin                                        NULL,
115f4259b30SLisandro Dalcin                                        NULL,
116f4259b30SLisandro Dalcin                                        NULL,
117f4259b30SLisandro Dalcin                                        /* 20*/ NULL,
118f4259b30SLisandro Dalcin                                        NULL,
119f4259b30SLisandro Dalcin                                        NULL,
120f4259b30SLisandro Dalcin                                        NULL,
121f4259b30SLisandro Dalcin                                        /* 24*/ NULL,
122f4259b30SLisandro Dalcin                                        NULL,
123f4259b30SLisandro Dalcin                                        NULL,
124f4259b30SLisandro Dalcin                                        NULL,
125f4259b30SLisandro Dalcin                                        NULL,
126f4259b30SLisandro Dalcin                                        /* 29*/ NULL,
127f4259b30SLisandro Dalcin                                        NULL,
128f4259b30SLisandro Dalcin                                        NULL,
129f4259b30SLisandro Dalcin                                        NULL,
130f4259b30SLisandro Dalcin                                        NULL,
131f4259b30SLisandro Dalcin                                        /* 34*/ NULL,
132f4259b30SLisandro Dalcin                                        NULL,
133f4259b30SLisandro Dalcin                                        NULL,
134f4259b30SLisandro Dalcin                                        NULL,
135f4259b30SLisandro Dalcin                                        NULL,
136f4259b30SLisandro Dalcin                                        /* 39*/ NULL,
137f4259b30SLisandro Dalcin                                        NULL,
138f4259b30SLisandro Dalcin                                        NULL,
139f4259b30SLisandro Dalcin                                        NULL,
140f4259b30SLisandro Dalcin                                        NULL,
141f4259b30SLisandro Dalcin                                        /* 44*/ NULL,
142f4259b30SLisandro Dalcin                                        NULL,
1437d68702bSBarry Smith                                        MatShift_Basic,
144f4259b30SLisandro Dalcin                                        NULL,
145f4259b30SLisandro Dalcin                                        NULL,
146f4259b30SLisandro Dalcin                                        /* 49*/ NULL,
147f4259b30SLisandro Dalcin                                        NULL,
148f4259b30SLisandro Dalcin                                        NULL,
149f4259b30SLisandro Dalcin                                        NULL,
150f4259b30SLisandro Dalcin                                        NULL,
151f4259b30SLisandro Dalcin                                        /* 54*/ NULL,
152f4259b30SLisandro Dalcin                                        NULL,
153f4259b30SLisandro Dalcin                                        NULL,
154f4259b30SLisandro Dalcin                                        NULL,
155f4259b30SLisandro Dalcin                                        NULL,
156f4259b30SLisandro Dalcin                                        /* 59*/ NULL,
1572a6744ebSBarry Smith                                        MatDestroy_Scatter,
158f4259b30SLisandro Dalcin                                        NULL,
159f4259b30SLisandro Dalcin                                        NULL,
160f4259b30SLisandro Dalcin                                        NULL,
161f4259b30SLisandro Dalcin                                        /* 64*/ NULL,
162f4259b30SLisandro Dalcin                                        NULL,
163f4259b30SLisandro Dalcin                                        NULL,
164f4259b30SLisandro Dalcin                                        NULL,
165f4259b30SLisandro Dalcin                                        NULL,
166f4259b30SLisandro Dalcin                                        /* 69*/ NULL,
167f4259b30SLisandro Dalcin                                        NULL,
168f4259b30SLisandro Dalcin                                        NULL,
169f4259b30SLisandro Dalcin                                        NULL,
170f4259b30SLisandro Dalcin                                        NULL,
171f4259b30SLisandro Dalcin                                        /* 74*/ NULL,
172f4259b30SLisandro Dalcin                                        NULL,
173f4259b30SLisandro Dalcin                                        NULL,
174f4259b30SLisandro Dalcin                                        NULL,
175f4259b30SLisandro Dalcin                                        NULL,
176f4259b30SLisandro Dalcin                                        /* 79*/ NULL,
177f4259b30SLisandro Dalcin                                        NULL,
178f4259b30SLisandro Dalcin                                        NULL,
179f4259b30SLisandro Dalcin                                        NULL,
180f4259b30SLisandro Dalcin                                        NULL,
181f4259b30SLisandro Dalcin                                        /* 84*/ NULL,
182f4259b30SLisandro Dalcin                                        NULL,
183f4259b30SLisandro Dalcin                                        NULL,
184f4259b30SLisandro Dalcin                                        NULL,
185f4259b30SLisandro Dalcin                                        NULL,
186f4259b30SLisandro Dalcin                                        /* 89*/ NULL,
187f4259b30SLisandro Dalcin                                        NULL,
188f4259b30SLisandro Dalcin                                        NULL,
189f4259b30SLisandro Dalcin                                        NULL,
190f4259b30SLisandro Dalcin                                        NULL,
191f4259b30SLisandro Dalcin                                        /* 94*/ NULL,
192f4259b30SLisandro Dalcin                                        NULL,
193f4259b30SLisandro Dalcin                                        NULL,
194f4259b30SLisandro Dalcin                                        NULL,
195f4259b30SLisandro Dalcin                                        NULL,
196f4259b30SLisandro Dalcin                                        /*99*/ NULL,
197f4259b30SLisandro Dalcin                                        NULL,
198f4259b30SLisandro Dalcin                                        NULL,
199f4259b30SLisandro Dalcin                                        NULL,
200f4259b30SLisandro Dalcin                                        NULL,
201f4259b30SLisandro Dalcin                                        /*104*/ NULL,
202f4259b30SLisandro Dalcin                                        NULL,
203f4259b30SLisandro Dalcin                                        NULL,
204f4259b30SLisandro Dalcin                                        NULL,
205f4259b30SLisandro Dalcin                                        NULL,
206f4259b30SLisandro Dalcin                                        /*109*/ NULL,
207f4259b30SLisandro Dalcin                                        NULL,
208f4259b30SLisandro Dalcin                                        NULL,
209f4259b30SLisandro Dalcin                                        NULL,
210f4259b30SLisandro Dalcin                                        NULL,
211f4259b30SLisandro Dalcin                                        /*114*/ NULL,
212f4259b30SLisandro Dalcin                                        NULL,
213f4259b30SLisandro Dalcin                                        NULL,
214f4259b30SLisandro Dalcin                                        NULL,
215f4259b30SLisandro Dalcin                                        NULL,
216f4259b30SLisandro Dalcin                                        /*119*/ NULL,
217f4259b30SLisandro Dalcin                                        NULL,
218f4259b30SLisandro Dalcin                                        NULL,
219f4259b30SLisandro Dalcin                                        NULL,
220f4259b30SLisandro Dalcin                                        NULL,
221f4259b30SLisandro Dalcin                                        /*124*/ NULL,
222f4259b30SLisandro Dalcin                                        NULL,
223f4259b30SLisandro Dalcin                                        NULL,
224f4259b30SLisandro Dalcin                                        NULL,
225f4259b30SLisandro Dalcin                                        NULL,
226f4259b30SLisandro Dalcin                                        /*129*/ NULL,
227f4259b30SLisandro Dalcin                                        NULL,
228f4259b30SLisandro Dalcin                                        NULL,
229f4259b30SLisandro Dalcin                                        NULL,
230f4259b30SLisandro Dalcin                                        NULL,
231f4259b30SLisandro Dalcin                                        /*134*/ NULL,
232f4259b30SLisandro Dalcin                                        NULL,
233f4259b30SLisandro Dalcin                                        NULL,
234f4259b30SLisandro Dalcin                                        NULL,
235f4259b30SLisandro Dalcin                                        NULL,
236f4259b30SLisandro Dalcin                                        /*139*/ NULL,
237d70f29a3SPierre Jolivet                                        NULL,
238d70f29a3SPierre Jolivet                                        NULL,
239d70f29a3SPierre Jolivet                                        NULL,
240d70f29a3SPierre Jolivet                                        NULL,
241d70f29a3SPierre Jolivet                                        /*144*/ NULL,
242d70f29a3SPierre Jolivet                                        NULL,
243f4259b30SLisandro Dalcin                                        NULL,
24499a7f59eSMark Adams                                        NULL,
24599a7f59eSMark Adams                                        NULL,
2467fb60732SBarry Smith                                        NULL,
247dec0b466SHong Zhang                                        /*150*/ NULL,
248dec0b466SHong Zhang                                        NULL};
2492a6744ebSBarry Smith 
2502a6744ebSBarry Smith /*MC
2512ef1f0ffSBarry Smith    MATSCATTER - "scatter" - A matrix type that simply applies a `VecScatterBegin()` and `VecScatterEnd()` to perform `MatMult()`
2522a6744ebSBarry Smith 
2532a6744ebSBarry Smith   Level: advanced
2542a6744ebSBarry Smith 
255*283d8c04SPierre Jolivet .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, MatCreateScatter()`, `MatScatterSetVecScatter()`, `MatScatterGetVecScatter()`
2562a6744ebSBarry Smith M*/
2572a6744ebSBarry Smith 
258d71ae5a4SJacob Faibussowitsch PETSC_EXTERN PetscErrorCode MatCreate_Scatter(Mat A)
259d71ae5a4SJacob Faibussowitsch {
2602a6744ebSBarry Smith   Mat_Scatter *b;
2612a6744ebSBarry Smith 
2622a6744ebSBarry Smith   PetscFunctionBegin;
263aea10558SJacob Faibussowitsch   A->ops[0] = MatOps_Values;
2644dfa11a4SJacob Faibussowitsch   PetscCall(PetscNew(&b));
2652a6744ebSBarry Smith 
2662a6744ebSBarry Smith   A->data = (void *)b;
2672a6744ebSBarry Smith 
2689566063dSJacob Faibussowitsch   PetscCall(PetscLayoutSetUp(A->rmap));
2699566063dSJacob Faibussowitsch   PetscCall(PetscLayoutSetUp(A->cmap));
2702a6744ebSBarry Smith 
2712a6744ebSBarry Smith   A->assembled    = PETSC_TRUE;
2722a6744ebSBarry Smith   A->preallocated = PETSC_FALSE;
27374d95942SJed Brown 
2749566063dSJacob Faibussowitsch   PetscCall(PetscObjectChangeTypeName((PetscObject)A, MATSCATTER));
2753ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
2762a6744ebSBarry Smith }
2772a6744ebSBarry Smith 
27897929ea7SJunchao Zhang #include <petsc/private/sfimpl.h>
2792a6744ebSBarry Smith /*@C
28011a5261eSBarry Smith   MatCreateScatter - Creates a new matrix of `MatType` `MATSCATTER`, based on a VecScatter
2812a6744ebSBarry Smith 
282d083f849SBarry Smith   Collective
2832a6744ebSBarry Smith 
2842a6744ebSBarry Smith   Input Parameters:
2852a6744ebSBarry Smith + comm    - MPI communicator
28611a5261eSBarry Smith - scatter - a `VecScatter`
2872a6744ebSBarry Smith 
2882a6744ebSBarry Smith   Output Parameter:
2892a6744ebSBarry Smith . A - the matrix
2902a6744ebSBarry Smith 
2912a6744ebSBarry Smith   Level: intermediate
2922a6744ebSBarry Smith 
2932a6744ebSBarry Smith    PETSc requires that matrices and vectors being used for certain
2942a6744ebSBarry Smith    operations are partitioned accordingly.  For example, when
2952a6744ebSBarry Smith    creating a scatter matrix, A, that supports parallel matrix-vector
29611a5261eSBarry Smith    products using `MatMult`(A,x,y) the user should set the number
2972a6744ebSBarry Smith    of local matrix rows to be the number of local elements of the
2982a6744ebSBarry Smith    corresponding result vector, y. Note that this is information is
2992a6744ebSBarry Smith    required for use of the matrix interface routines, even though
3002a6744ebSBarry Smith    the scatter matrix may not actually be physically partitioned.
3012a6744ebSBarry Smith 
302fe59aa6dSJacob Faibussowitsch   Developer Notes:
30311a5261eSBarry Smith   This directly accesses information inside the `VecScatter` associated with the matrix-vector product
3046eb45d04SBarry Smith   for this matrix. This is not desirable..
3056eb45d04SBarry Smith 
3061cc06b55SBarry Smith .seealso: [](ch_matrices), `Mat`, `MatScatterSetVecScatter()`, `MatScatterGetVecScatter()`, `MATSCATTER`
3072a6744ebSBarry Smith @*/
308d71ae5a4SJacob Faibussowitsch PetscErrorCode MatCreateScatter(MPI_Comm comm, VecScatter scatter, Mat *A)
309d71ae5a4SJacob Faibussowitsch {
3102a6744ebSBarry Smith   PetscFunctionBegin;
3119566063dSJacob Faibussowitsch   PetscCall(MatCreate(comm, A));
3129566063dSJacob Faibussowitsch   PetscCall(MatSetSizes(*A, scatter->vscat.to_n, scatter->vscat.from_n, PETSC_DETERMINE, PETSC_DETERMINE));
3139566063dSJacob Faibussowitsch   PetscCall(MatSetType(*A, MATSCATTER));
3149566063dSJacob Faibussowitsch   PetscCall(MatScatterSetVecScatter(*A, scatter));
3159566063dSJacob Faibussowitsch   PetscCall(MatSetUp(*A));
3163ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
3172a6744ebSBarry Smith }
3182a6744ebSBarry Smith 
3192a6744ebSBarry Smith /*@
32011a5261eSBarry Smith   MatScatterSetVecScatter - sets the scatter that the matrix is to apply as its linear operator in a `MATSCATTER`
3212a6744ebSBarry Smith 
3222ef1f0ffSBarry Smith   Logically Collective
3232a6744ebSBarry Smith 
3242a6744ebSBarry Smith   Input Parameters:
32511a5261eSBarry Smith + mat     - the `MATSCATTER` matrix
32611a5261eSBarry Smith - scatter - the scatter context create with `VecScatterCreate()`
3272a6744ebSBarry Smith 
3282a6744ebSBarry Smith   Level: advanced
3292a6744ebSBarry Smith 
330fe59aa6dSJacob Faibussowitsch .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, `MatCreateScatter()`
3312a6744ebSBarry Smith @*/
332d71ae5a4SJacob Faibussowitsch PetscErrorCode MatScatterSetVecScatter(Mat mat, VecScatter scatter)
333d71ae5a4SJacob Faibussowitsch {
3342a6744ebSBarry Smith   Mat_Scatter *mscatter = (Mat_Scatter *)mat->data;
3352a6744ebSBarry Smith 
3362a6744ebSBarry Smith   PetscFunctionBegin;
3370700a824SBarry Smith   PetscValidHeaderSpecific(mat, MAT_CLASSID, 1);
33897929ea7SJunchao Zhang   PetscValidHeaderSpecific(scatter, PETSCSF_CLASSID, 2);
339064a246eSJacob Faibussowitsch   PetscCheckSameComm((PetscObject)scatter, 2, (PetscObject)mat, 1);
34008401ef6SPierre Jolivet   PetscCheck(mat->rmap->n == scatter->vscat.to_n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Number of local rows in matrix %" PetscInt_FMT " not equal local scatter size %" PetscInt_FMT, mat->rmap->n, scatter->vscat.to_n);
34108401ef6SPierre Jolivet   PetscCheck(mat->cmap->n == scatter->vscat.from_n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Number of local columns in matrix %" PetscInt_FMT " not equal local scatter size %" PetscInt_FMT, mat->cmap->n, scatter->vscat.from_n);
3422a6744ebSBarry Smith 
3439566063dSJacob Faibussowitsch   PetscCall(PetscObjectReference((PetscObject)scatter));
3449566063dSJacob Faibussowitsch   PetscCall(VecScatterDestroy(&mscatter->scatter));
34526fbe8dcSKarl Rupp 
3462a6744ebSBarry Smith   mscatter->scatter = scatter;
3473ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
3482a6744ebSBarry Smith }
349