Actual source code: mattransposematmult.c


  2: /*
  3:   Defines matrix-matrix product routines for
  4:           C = A^T * B and C = A * B^t
  5:   with A SeqAIJ and B SeqDense
  6: */

  8: #include <../src/mat/impls/aij/seq/aij.h>
  9: #include <../src/mat/impls/dense/seq/dense.h>

 11: PetscErrorCode MatDestroy_SeqDense_MatTransMatMult(void *data)
 12: {
 13:   Mat_MatTransMatMult *atb = (Mat_MatTransMatMult *)data;

 15:   PetscFunctionBegin;
 16:   PetscCall(MatDestroy(&atb->mA));
 17:   PetscCall(VecDestroy(&atb->bt));
 18:   PetscCall(VecDestroy(&atb->ct));
 19:   PetscCall(PetscFree(atb));
 20:   PetscFunctionReturn(PETSC_SUCCESS);
 21: }

 23: static PetscErrorCode MatTMatTMultNumeric_SeqAIJ_SeqDense(Mat, Mat, Mat);

 25: PETSC_INTERN PetscErrorCode MatTMatTMultSymbolic_SeqAIJ_SeqDense(Mat A, Mat B, PetscReal fill, Mat C)
 26: {
 27:   Mat_MatTransMatMult *atb;
 28:   PetscBool            cisdense;
 29:   PetscInt             dofm;

 31:   PetscFunctionBegin;
 32:   MatCheckProduct(C, 4);
 33:   PetscCheck(!C->product->data, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Extra product struct not empty");
 34:   PetscCheck(C->product->type == MATPRODUCT_ABt || C->product->type == MATPRODUCT_AtB, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[C->product->type]);

 36:   /* create output dense matrix C */
 37:   if (C->product->type == MATPRODUCT_AtB) {
 38:     PetscCall(MatSetSizes(C, A->cmap->n, B->cmap->N, A->cmap->n, B->cmap->N));
 39:     dofm = B->cmap->n;
 40:   } else {
 41:     PetscCall(MatSetSizes(C, A->rmap->n, B->rmap->N, A->rmap->n, B->rmap->N));
 42:     dofm = B->rmap->n;
 43:   }
 44:   PetscCall(PetscObjectTypeCompareAny((PetscObject)C, &cisdense, MATSEQDENSE, MATSEQDENSECUDA, ""));
 45:   if (!cisdense) PetscCall(MatSetType(C, ((PetscObject)B)->type_name));
 46:   PetscCall(MatSetUp(C));

 48:   /* create additional data structure for the product */
 49:   PetscCall(PetscNew(&atb));
 50:   PetscCall(MatCreateMAIJ(A, dofm, &atb->mA));
 51:   PetscCall(MatCreateVecs(atb->mA, &atb->ct, &atb->bt));
 52:   C->product->data    = atb;
 53:   C->product->destroy = MatDestroy_SeqDense_MatTransMatMult;

 55:   if (C->product->type == MATPRODUCT_AtB) {
 56:     C->ops->transposematmultnumeric = MatTMatTMultNumeric_SeqAIJ_SeqDense;
 57:   } else {
 58:     C->ops->mattransposemultnumeric = MatTMatTMultNumeric_SeqAIJ_SeqDense;
 59:   }
 60:   PetscFunctionReturn(PETSC_SUCCESS);
 61: }

 63: PetscErrorCode MatTMatTMultNumeric_SeqAIJ_SeqDense(Mat A, Mat B, Mat C)
 64: {
 65:   PetscInt             i, j, m = A->rmap->n, n = A->cmap->n, blda, clda;
 66:   PetscInt             mdof = C->cmap->N;
 67:   const PetscScalar   *Barray;
 68:   PetscScalar         *Carray;
 69:   Mat_MatTransMatMult *atb;
 70:   Vec                  bt, ct;

 72:   PetscFunctionBegin;
 73:   MatCheckProduct(C, 3);
 74:   PetscCheck(C->product->type == MATPRODUCT_ABt || C->product->type == MATPRODUCT_AtB, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Not for product type %s", MatProductTypes[C->product->type]);
 75:   atb = (Mat_MatTransMatMult *)C->product->data;
 76:   PetscCheck(atb, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Missing product struct");
 77:   bt = atb->bt;
 78:   ct = atb->ct;

 80:   PetscCall(MatDenseGetArrayRead(B, &Barray));
 81:   PetscCall(MatDenseGetLDA(B, &blda));
 82:   PetscCall(MatDenseGetArrayWrite(C, &Carray));
 83:   PetscCall(MatDenseGetLDA(C, &clda));
 84:   if (C->product->type == MATPRODUCT_AtB) { /* transpose local array of B, then copy it to vector bt */
 85:     const PetscScalar *ctarray;
 86:     PetscScalar       *btarray;

 88:     PetscCall(VecGetArrayWrite(bt, &btarray));
 89:     for (j = 0; j < mdof; j++) {
 90:       for (i = 0; i < m; i++) btarray[i * mdof + j] = Barray[j * blda + i];
 91:     }
 92:     PetscCall(VecRestoreArrayWrite(bt, &btarray));

 94:     /* compute ct = mA^T * cb */
 95:     PetscCall(MatMultTranspose(atb->mA, bt, ct));

 97:     /* transpose local array of ct to matrix C */
 98:     PetscCall(VecGetArrayRead(ct, &ctarray));
 99:     for (j = 0; j < mdof; j++) {
100:       for (i = 0; i < n; i++) Carray[j * clda + i] = ctarray[i * mdof + j];
101:     }
102:     PetscCall(VecRestoreArrayRead(ct, &ctarray));
103:   } else {
104:     const PetscScalar *btarray;
105:     PetscScalar       *ctarray;

107:     if (blda == B->rmap->n) {
108:       PetscCall(VecPlaceArray(ct, Barray));
109:     } else {
110:       PetscInt bn = B->cmap->n;
111:       PetscInt bm = B->rmap->n;

113:       PetscCall(VecGetArrayWrite(ct, &ctarray));
114:       for (j = 0; j < bn; j++) {
115:         for (i = 0; i < bm; i++) ctarray[j * bm + i] = Barray[j * blda + i];
116:       }
117:       PetscCall(VecRestoreArrayWrite(ct, &ctarray));
118:     }

120:     PetscCall(MatMult(atb->mA, ct, bt));
121:     if (blda == B->rmap->n) PetscCall(VecResetArray(ct));
122:     PetscCall(VecGetArrayRead(bt, &btarray));
123:     for (j = 0; j < mdof; j++) {
124:       for (i = 0; i < m; i++) Carray[j * clda + i] = btarray[i * mdof + j];
125:     }
126:     PetscCall(VecRestoreArrayRead(bt, &btarray));
127:   }
128:   PetscCall(MatDenseRestoreArrayRead(B, &Barray));
129:   PetscCall(MatDenseRestoreArray(C, &Carray));
130:   PetscFunctionReturn(PETSC_SUCCESS);
131: }