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 /*144*/ NULL, 242 NULL, 243 NULL, 244 NULL, 245 NULL, 246 NULL, 247 /*150*/ NULL, 248 NULL, 249 NULL, 250 NULL}; 251 252 /*MC 253 MATSCATTER - "scatter" - A matrix type that simply applies a `VecScatterBegin()` and `VecScatterEnd()` to perform `MatMult()` 254 255 Level: advanced 256 257 .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, MatCreateScatter()`, `MatScatterSetVecScatter()`, `MatScatterGetVecScatter()` 258 M*/ 259 260 PETSC_EXTERN PetscErrorCode MatCreate_Scatter(Mat A) 261 { 262 Mat_Scatter *b; 263 264 PetscFunctionBegin; 265 A->ops[0] = MatOps_Values; 266 PetscCall(PetscNew(&b)); 267 268 A->data = (void *)b; 269 270 PetscCall(PetscLayoutSetUp(A->rmap)); 271 PetscCall(PetscLayoutSetUp(A->cmap)); 272 273 A->assembled = PETSC_TRUE; 274 A->preallocated = PETSC_FALSE; 275 276 PetscCall(PetscObjectChangeTypeName((PetscObject)A, MATSCATTER)); 277 PetscFunctionReturn(PETSC_SUCCESS); 278 } 279 280 #include <petsc/private/sfimpl.h> 281 /*@ 282 MatCreateScatter - Creates a new matrix of `MatType` `MATSCATTER`, based on a VecScatter 283 284 Collective 285 286 Input Parameters: 287 + comm - MPI communicator 288 - scatter - a `VecScatter` 289 290 Output Parameter: 291 . A - the matrix 292 293 Level: intermediate 294 295 Notes: 296 PETSc requires that matrices and vectors being used for certain 297 operations are partitioned accordingly. For example, when 298 creating a scatter matrix, A, that supports parallel matrix-vector 299 products using `MatMult`(A,x,y) the user should set the number 300 of local matrix rows to be the number of local elements of the 301 corresponding result vector, y. Note that this is information is 302 required for use of the matrix interface routines, even though 303 the scatter matrix may not actually be physically partitioned. 304 305 Developer Notes: 306 This directly accesses information inside the `VecScatter` associated with the matrix-vector product 307 for this matrix. This is not desirable.. 308 309 .seealso: [](ch_matrices), `Mat`, `MatScatterSetVecScatter()`, `MatScatterGetVecScatter()`, `MATSCATTER` 310 @*/ 311 PetscErrorCode MatCreateScatter(MPI_Comm comm, VecScatter scatter, Mat *A) 312 { 313 PetscFunctionBegin; 314 PetscCall(MatCreate(comm, A)); 315 PetscCall(MatSetSizes(*A, scatter->vscat.to_n, scatter->vscat.from_n, PETSC_DETERMINE, PETSC_DETERMINE)); 316 PetscCall(MatSetType(*A, MATSCATTER)); 317 PetscCall(MatScatterSetVecScatter(*A, scatter)); 318 PetscCall(MatSetUp(*A)); 319 PetscFunctionReturn(PETSC_SUCCESS); 320 } 321 322 /*@ 323 MatScatterSetVecScatter - sets the scatter that the matrix is to apply as its linear operator in a `MATSCATTER` 324 325 Logically Collective 326 327 Input Parameters: 328 + mat - the `MATSCATTER` matrix 329 - scatter - the scatter context create with `VecScatterCreate()` 330 331 Level: advanced 332 333 .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, `MatCreateScatter()` 334 @*/ 335 PetscErrorCode MatScatterSetVecScatter(Mat mat, VecScatter scatter) 336 { 337 Mat_Scatter *mscatter = (Mat_Scatter *)mat->data; 338 339 PetscFunctionBegin; 340 PetscValidHeaderSpecific(mat, MAT_CLASSID, 1); 341 PetscValidHeaderSpecific(scatter, PETSCSF_CLASSID, 2); 342 PetscCheckSameComm((PetscObject)scatter, 2, (PetscObject)mat, 1); 343 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); 344 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); 345 346 PetscCall(PetscObjectReference((PetscObject)scatter)); 347 PetscCall(VecScatterDestroy(&mscatter->scatter)); 348 349 mscatter->scatter = scatter; 350 PetscFunctionReturn(PETSC_SUCCESS); 351 } 352