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}; 240 241 /*MC 242 MATSCATTER - "scatter" - A matrix type that simply applies a `VecScatterBegin()` and `VecScatterEnd()` to perform `MatMult()` 243 244 Level: advanced 245 246 .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, MatCreateScatter()`, `MatScatterSetVecScatter()`, `MatScatterGetVecScatter()` 247 M*/ 248 249 PETSC_EXTERN PetscErrorCode MatCreate_Scatter(Mat A) 250 { 251 Mat_Scatter *b; 252 253 PetscFunctionBegin; 254 A->ops[0] = MatOps_Values; 255 PetscCall(PetscNew(&b)); 256 257 A->data = (void *)b; 258 259 PetscCall(PetscLayoutSetUp(A->rmap)); 260 PetscCall(PetscLayoutSetUp(A->cmap)); 261 262 A->assembled = PETSC_TRUE; 263 A->preallocated = PETSC_FALSE; 264 265 PetscCall(PetscObjectChangeTypeName((PetscObject)A, MATSCATTER)); 266 PetscFunctionReturn(PETSC_SUCCESS); 267 } 268 269 #include <petsc/private/sfimpl.h> 270 /*@ 271 MatCreateScatter - Creates a new matrix of `MatType` `MATSCATTER`, based on a VecScatter 272 273 Collective 274 275 Input Parameters: 276 + comm - MPI communicator 277 - scatter - a `VecScatter` 278 279 Output Parameter: 280 . A - the matrix 281 282 Level: intermediate 283 284 Notes: 285 PETSc requires that matrices and vectors being used for certain 286 operations are partitioned accordingly. For example, when 287 creating a scatter matrix, A, that supports parallel matrix-vector 288 products using `MatMult`(A,x,y) the user should set the number 289 of local matrix rows to be the number of local elements of the 290 corresponding result vector, y. Note that this is information is 291 required for use of the matrix interface routines, even though 292 the scatter matrix may not actually be physically partitioned. 293 294 Developer Notes: 295 This directly accesses information inside the `VecScatter` associated with the matrix-vector product 296 for this matrix. This is not desirable.. 297 298 .seealso: [](ch_matrices), `Mat`, `MatScatterSetVecScatter()`, `MatScatterGetVecScatter()`, `MATSCATTER` 299 @*/ 300 PetscErrorCode MatCreateScatter(MPI_Comm comm, VecScatter scatter, Mat *A) 301 { 302 PetscFunctionBegin; 303 PetscCall(MatCreate(comm, A)); 304 PetscCall(MatSetSizes(*A, scatter->vscat.to_n, scatter->vscat.from_n, PETSC_DETERMINE, PETSC_DETERMINE)); 305 PetscCall(MatSetType(*A, MATSCATTER)); 306 PetscCall(MatScatterSetVecScatter(*A, scatter)); 307 PetscCall(MatSetUp(*A)); 308 PetscFunctionReturn(PETSC_SUCCESS); 309 } 310 311 /*@ 312 MatScatterSetVecScatter - sets the scatter that the matrix is to apply as its linear operator in a `MATSCATTER` 313 314 Logically Collective 315 316 Input Parameters: 317 + mat - the `MATSCATTER` matrix 318 - scatter - the scatter context create with `VecScatterCreate()` 319 320 Level: advanced 321 322 .seealso: [](ch_matrices), `Mat`, `MATSCATTER`, `MatCreateScatter()` 323 @*/ 324 PetscErrorCode MatScatterSetVecScatter(Mat mat, VecScatter scatter) 325 { 326 Mat_Scatter *mscatter = (Mat_Scatter *)mat->data; 327 328 PetscFunctionBegin; 329 PetscValidHeaderSpecific(mat, MAT_CLASSID, 1); 330 PetscValidHeaderSpecific(scatter, PETSCSF_CLASSID, 2); 331 PetscCheckSameComm(scatter, 2, mat, 1); 332 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); 333 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); 334 335 PetscCall(PetscObjectReference((PetscObject)scatter)); 336 PetscCall(VecScatterDestroy(&mscatter->scatter)); 337 338 mscatter->scatter = scatter; 339 PetscFunctionReturn(PETSC_SUCCESS); 340 } 341