1 /* 2 This provides a matrix that applies a VecScatter to a vector. 3 */ 4 5 #include <petsc/private/matimpl.h> /*I "petscmat.h" I*/ 6 #include <petsc/private/vecimpl.h> 7 8 typedef struct { 9 VecScatter scatter; 10 } Mat_Scatter; 11 12 /*@ 13 MatScatterGetVecScatter - Returns the user-provided scatter set with `MatScatterSetVecScatter()` in a `MATSCATTER` matrix 14 15 Logically Collective 16 17 Input Parameter: 18 . mat - the matrix, should have been created with MatCreateScatter() or have type `MATSCATTER` 19 20 Output Parameter: 21 . scatter - the scatter context 22 23 Level: intermediate 24 25 .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, `MatCreateScatter()`, `MatScatterSetVecScatter()` 26 @*/ 27 PetscErrorCode MatScatterGetVecScatter(Mat mat, VecScatter *scatter) 28 { 29 Mat_Scatter *mscatter; 30 31 PetscFunctionBegin; 32 PetscValidHeaderSpecific(mat, MAT_CLASSID, 1); 33 PetscAssertPointer(scatter, 2); 34 mscatter = (Mat_Scatter *)mat->data; 35 *scatter = mscatter->scatter; 36 PetscFunctionReturn(PETSC_SUCCESS); 37 } 38 39 static PetscErrorCode MatDestroy_Scatter(Mat mat) 40 { 41 Mat_Scatter *scatter = (Mat_Scatter *)mat->data; 42 43 PetscFunctionBegin; 44 PetscCall(VecScatterDestroy(&scatter->scatter)); 45 PetscCall(PetscFree(mat->data)); 46 PetscFunctionReturn(PETSC_SUCCESS); 47 } 48 49 static PetscErrorCode MatMult_Scatter(Mat A, Vec x, Vec y) 50 { 51 Mat_Scatter *scatter = (Mat_Scatter *)A->data; 52 53 PetscFunctionBegin; 54 PetscCheck(scatter->scatter, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "Need to first call MatScatterSetScatter()"); 55 PetscCall(VecZeroEntries(y)); 56 PetscCall(VecScatterBegin(scatter->scatter, x, y, ADD_VALUES, SCATTER_FORWARD)); 57 PetscCall(VecScatterEnd(scatter->scatter, x, y, ADD_VALUES, SCATTER_FORWARD)); 58 PetscFunctionReturn(PETSC_SUCCESS); 59 } 60 61 static PetscErrorCode MatMultAdd_Scatter(Mat A, Vec x, Vec y, Vec z) 62 { 63 Mat_Scatter *scatter = (Mat_Scatter *)A->data; 64 65 PetscFunctionBegin; 66 PetscCheck(scatter->scatter, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "Need to first call MatScatterSetScatter()"); 67 if (z != y) PetscCall(VecCopy(y, z)); 68 PetscCall(VecScatterBegin(scatter->scatter, x, z, ADD_VALUES, SCATTER_FORWARD)); 69 PetscCall(VecScatterEnd(scatter->scatter, x, z, ADD_VALUES, SCATTER_FORWARD)); 70 PetscFunctionReturn(PETSC_SUCCESS); 71 } 72 73 static PetscErrorCode MatMultTranspose_Scatter(Mat A, Vec x, Vec y) 74 { 75 Mat_Scatter *scatter = (Mat_Scatter *)A->data; 76 77 PetscFunctionBegin; 78 PetscCheck(scatter->scatter, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "Need to first call MatScatterSetScatter()"); 79 PetscCall(VecZeroEntries(y)); 80 PetscCall(VecScatterBegin(scatter->scatter, x, y, ADD_VALUES, SCATTER_REVERSE)); 81 PetscCall(VecScatterEnd(scatter->scatter, x, y, ADD_VALUES, SCATTER_REVERSE)); 82 PetscFunctionReturn(PETSC_SUCCESS); 83 } 84 85 static PetscErrorCode MatMultTransposeAdd_Scatter(Mat A, Vec x, Vec y, Vec z) 86 { 87 Mat_Scatter *scatter = (Mat_Scatter *)A->data; 88 89 PetscFunctionBegin; 90 PetscCheck(scatter->scatter, PetscObjectComm((PetscObject)A), PETSC_ERR_ARG_WRONGSTATE, "Need to first call MatScatterSetScatter()"); 91 if (z != y) PetscCall(VecCopy(y, z)); 92 PetscCall(VecScatterBegin(scatter->scatter, x, z, ADD_VALUES, SCATTER_REVERSE)); 93 PetscCall(VecScatterEnd(scatter->scatter, x, z, ADD_VALUES, SCATTER_REVERSE)); 94 PetscFunctionReturn(PETSC_SUCCESS); 95 } 96 97 static struct _MatOps MatOps_Values = {NULL, 98 NULL, 99 NULL, 100 MatMult_Scatter, 101 /* 4*/ MatMultAdd_Scatter, 102 MatMultTranspose_Scatter, 103 MatMultTransposeAdd_Scatter, 104 NULL, 105 NULL, 106 NULL, 107 /* 10*/ NULL, 108 NULL, 109 NULL, 110 NULL, 111 NULL, 112 /* 15*/ NULL, 113 NULL, 114 NULL, 115 NULL, 116 NULL, 117 /* 20*/ NULL, 118 NULL, 119 NULL, 120 NULL, 121 /* 24*/ NULL, 122 NULL, 123 NULL, 124 NULL, 125 NULL, 126 /* 29*/ NULL, 127 NULL, 128 NULL, 129 NULL, 130 NULL, 131 /* 34*/ NULL, 132 NULL, 133 NULL, 134 NULL, 135 NULL, 136 /* 39*/ NULL, 137 NULL, 138 NULL, 139 NULL, 140 NULL, 141 /* 44*/ NULL, 142 NULL, 143 MatShift_Basic, 144 NULL, 145 NULL, 146 /* 49*/ NULL, 147 NULL, 148 NULL, 149 NULL, 150 NULL, 151 /* 54*/ NULL, 152 NULL, 153 NULL, 154 NULL, 155 NULL, 156 /* 59*/ NULL, 157 MatDestroy_Scatter, 158 NULL, 159 NULL, 160 NULL, 161 /* 64*/ NULL, 162 NULL, 163 NULL, 164 NULL, 165 NULL, 166 /* 69*/ NULL, 167 NULL, 168 NULL, 169 NULL, 170 NULL, 171 /* 74*/ NULL, 172 NULL, 173 NULL, 174 NULL, 175 NULL, 176 /* 79*/ NULL, 177 NULL, 178 NULL, 179 NULL, 180 NULL, 181 /* 84*/ NULL, 182 NULL, 183 NULL, 184 NULL, 185 NULL, 186 /* 89*/ NULL, 187 NULL, 188 NULL, 189 NULL, 190 NULL, 191 /* 94*/ NULL, 192 NULL, 193 NULL, 194 NULL, 195 NULL, 196 /*99*/ NULL, 197 NULL, 198 NULL, 199 NULL, 200 NULL, 201 /*104*/ NULL, 202 NULL, 203 NULL, 204 NULL, 205 NULL, 206 /*109*/ NULL, 207 NULL, 208 NULL, 209 NULL, 210 NULL, 211 /*114*/ NULL, 212 NULL, 213 NULL, 214 NULL, 215 NULL, 216 /*119*/ NULL, 217 NULL, 218 NULL, 219 NULL, 220 NULL, 221 /*124*/ NULL, 222 NULL, 223 NULL, 224 NULL, 225 NULL, 226 /*129*/ NULL, 227 NULL, 228 NULL, 229 NULL, 230 NULL, 231 /*134*/ NULL, 232 NULL, 233 NULL, 234 NULL, 235 NULL, 236 /*139*/ NULL, 237 NULL, 238 NULL, 239 NULL, 240 NULL}; 241 242 /*MC 243 MATSCATTER - "scatter" - A matrix type that simply applies a `VecScatterBegin()` and `VecScatterEnd()` to perform `MatMult()` 244 245 Level: advanced 246 247 .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, MatCreateScatter()`, `MatScatterSetVecScatter()`, `MatScatterGetVecScatter()` 248 M*/ 249 250 PETSC_EXTERN PetscErrorCode MatCreate_Scatter(Mat A) 251 { 252 Mat_Scatter *b; 253 254 PetscFunctionBegin; 255 A->ops[0] = MatOps_Values; 256 PetscCall(PetscNew(&b)); 257 258 A->data = (void *)b; 259 260 PetscCall(PetscLayoutSetUp(A->rmap)); 261 PetscCall(PetscLayoutSetUp(A->cmap)); 262 263 A->assembled = PETSC_TRUE; 264 A->preallocated = PETSC_FALSE; 265 266 PetscCall(PetscObjectChangeTypeName((PetscObject)A, MATSCATTER)); 267 PetscFunctionReturn(PETSC_SUCCESS); 268 } 269 270 #include <petsc/private/sfimpl.h> 271 /*@ 272 MatCreateScatter - Creates a new matrix of `MatType` `MATSCATTER`, based on a VecScatter 273 274 Collective 275 276 Input Parameters: 277 + comm - MPI communicator 278 - scatter - a `VecScatter` 279 280 Output Parameter: 281 . A - the matrix 282 283 Level: intermediate 284 285 Notes: 286 PETSc requires that matrices and vectors being used for certain 287 operations are partitioned accordingly. For example, when 288 creating a scatter matrix, A, that supports parallel matrix-vector 289 products using `MatMult`(A,x,y) the user should set the number 290 of local matrix rows to be the number of local elements of the 291 corresponding result vector, y. Note that this is information is 292 required for use of the matrix interface routines, even though 293 the scatter matrix may not actually be physically partitioned. 294 295 Developer Notes: 296 This directly accesses information inside the `VecScatter` associated with the matrix-vector product 297 for this matrix. This is not desirable.. 298 299 .seealso: [](ch_matrices), `Mat`, `MatScatterSetVecScatter()`, `MatScatterGetVecScatter()`, `MATSCATTER` 300 @*/ 301 PetscErrorCode MatCreateScatter(MPI_Comm comm, VecScatter scatter, Mat *A) 302 { 303 PetscFunctionBegin; 304 PetscCall(MatCreate(comm, A)); 305 PetscCall(MatSetSizes(*A, scatter->vscat.to_n, scatter->vscat.from_n, PETSC_DETERMINE, PETSC_DETERMINE)); 306 PetscCall(MatSetType(*A, MATSCATTER)); 307 PetscCall(MatScatterSetVecScatter(*A, scatter)); 308 PetscCall(MatSetUp(*A)); 309 PetscFunctionReturn(PETSC_SUCCESS); 310 } 311 312 /*@ 313 MatScatterSetVecScatter - sets the scatter that the matrix is to apply as its linear operator in a `MATSCATTER` 314 315 Logically Collective 316 317 Input Parameters: 318 + mat - the `MATSCATTER` matrix 319 - scatter - the scatter context create with `VecScatterCreate()` 320 321 Level: advanced 322 323 .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, `MatCreateScatter()` 324 @*/ 325 PetscErrorCode MatScatterSetVecScatter(Mat mat, VecScatter scatter) 326 { 327 Mat_Scatter *mscatter = (Mat_Scatter *)mat->data; 328 329 PetscFunctionBegin; 330 PetscValidHeaderSpecific(mat, MAT_CLASSID, 1); 331 PetscValidHeaderSpecific(scatter, PETSCSF_CLASSID, 2); 332 PetscCheckSameComm(scatter, 2, mat, 1); 333 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); 334 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); 335 336 PetscCall(PetscObjectReference((PetscObject)scatter)); 337 PetscCall(VecScatterDestroy(&mscatter->scatter)); 338 339 mscatter->scatter = scatter; 340 PetscFunctionReturn(PETSC_SUCCESS); 341 } 342