2: /*
  3:   Defines matrix-matrix product routines for pairs of MPIAIJ matrices
  4:           C = A^T * B
  5:   The routines are slightly modified from MatTransposeMatMultxxx_SeqAIJ_SeqDense().
  6: */
  7:  #include <../src/mat/impls/aij/seq/aij.h>
  8:  #include <../src/mat/impls/aij/mpi/mpiaij.h>
  9:  #include <../src/mat/impls/dense/mpi/mpidense.h>

 11: PetscErrorCode MatDestroy_MPIDense_MatTransMatMult(Mat A)
 12: {
 13:   PetscErrorCode      ierr;
 14:   Mat_MPIDense        *a = (Mat_MPIDense*)A->data;
 15:   Mat_MatTransMatMult *atb = a->atb;

 18:   MatDestroy(&atb->mA);
 19:   VecDestroy(&atb->bt);
 20:   VecDestroy(&atb->ct);
 21:   (atb->destroy)(A);
 22:   PetscFree(atb);
 23:   return(0);
 24: }

 26: PetscErrorCode MatTransposeMatMultSymbolic_MPIAIJ_MPIDense(Mat A,Mat B,PetscReal fill,Mat C)
 27: {
 28:   PetscErrorCode      ierr;
 29:   PetscInt            m=A->rmap->n,n=A->cmap->n,BN=B->cmap->N;
 30:   Mat_MatTransMatMult *atb;
 31:   Vec                 bt,ct;
 32:   Mat_MPIDense        *c;

 35:   PetscNew(&atb);

 37:   /* create output dense matrix C = A^T*B */
 38:   MatSetSizes(C,n,B->cmap->n,A->cmap->N,BN);
 39:   MatSetType(C,MATMPIDENSE);
 40:   MatSetUp(C);

 42:   /* create vectors bt and ct to hold locally transposed arrays of B and C */
 43:   VecCreate(PetscObjectComm((PetscObject)A),&bt);
 44:   VecSetSizes(bt,m*BN,PETSC_DECIDE);
 45:   VecSetType(bt,VECSTANDARD);
 46:   VecCreate(PetscObjectComm((PetscObject)A),&ct);
 47:   VecSetSizes(ct,n*BN,PETSC_DECIDE);
 48:   VecSetType(ct,VECSTANDARD);
 49:   atb->bt = bt;
 50:   atb->ct = ct;

 52:   c                               = (Mat_MPIDense*)C->data;
 53:   c->atb                          = atb;
 54:   atb->destroy                    = C->ops->destroy;
 55:   C->ops->destroy                 = MatDestroy_MPIDense_MatTransMatMult;
 56:   C->ops->transposematmultnumeric = MatTransposeMatMultNumeric_MPIAIJ_MPIDense;
 57:   return(0);
 58: }

 60: PetscErrorCode MatTransposeMatMultNumeric_MPIAIJ_MPIDense(Mat A,Mat B,Mat C)
 61: {
 62:   PetscErrorCode      ierr;
 63:   const PetscScalar   *Barray,*ctarray;
 64:   PetscScalar         *Carray,*btarray;
 65:   Mat_MPIDense        *b=(Mat_MPIDense*)B->data,*c=(Mat_MPIDense*)C->data;
 66:   Mat_SeqDense        *bseq=(Mat_SeqDense*)(b->A)->data,*cseq=(Mat_SeqDense*)(c->A)->data;
 67:   PetscInt            i,j,m=A->rmap->n,n=A->cmap->n,ldb=bseq->lda,BN=B->cmap->N,ldc=cseq->lda;
 68:   Mat_MatTransMatMult *atb=c->atb;
 69:   Vec                 bt=atb->bt,ct=atb->ct;

 72:   /* create MAIJ matrix mA from A -- should be done in symbolic phase */
 73:   MatDestroy(&atb->mA);
 74:   MatCreateMAIJ(A,BN,&atb->mA);

 76:   /* transpose local arry of B, then copy it to vector bt */
 77:   MatDenseGetArrayRead(B,&Barray);
 78:   VecGetArray(bt,&btarray);

 80:   for (j=0; j<BN; j++) {
 81:     for (i=0; i<m; i++) btarray[i*BN + j] = Barray[j*ldb + i];
 82:   }
 83:   VecRestoreArray(bt,&btarray);
 84:   MatDenseRestoreArrayRead(B,&Barray);

 86:   /* compute ct = mA^T * cb */
 87:   MatMultTranspose(atb->mA,bt,ct);

 89:   /* transpose local array of ct to matrix C */
 90:   MatDenseGetArray(C,&Carray);
 91:   VecGetArrayRead(ct,&ctarray);

 93:   for (j=0; j<BN; j++) {
 94:     for (i=0; i<n; i++) Carray[j*ldc + i] = ctarray[i*BN + j];
 95:   }
 96:   VecRestoreArrayRead(ct,&ctarray);
 97:   MatDenseRestoreArray(C,&Carray);
 98:   MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
 99:   MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);
100:   return(0);
101: }