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> /*I "petscmat.h" I*/
  8: #include <../src/mat/impls/aij/mpi/mpiaij.h>
  9: #include <../src/mat/impls/dense/mpi/mpidense.h>

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

 20:   MatDestroy(&atb->mA);
 21:   VecDestroy(&atb->bt);
 22:   VecDestroy(&atb->ct);
 23:   (atb->destroy)(A);
 24:   PetscFree(atb);
 25:   return(0);
 26: }

 30: PetscErrorCode MatTransposeMatMult_MPIAIJ_MPIDense(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
 31: {

 35:   if (scall == MAT_INITIAL_MATRIX) {
 36:     PetscLogEventBegin(MAT_TransposeMatMultSymbolic,A,B,0,0);
 37:     MatTransposeMatMultSymbolic_MPIAIJ_MPIDense(A,B,fill,C);
 38:     PetscLogEventEnd(MAT_TransposeMatMultSymbolic,A,B,0,0);
 39:   }
 40:   PetscLogEventBegin(MAT_TransposeMatMultNumeric,A,B,0,0);
 41:   MatTransposeMatMultNumeric_MPIAIJ_MPIDense(A,B,*C);
 42:   PetscLogEventEnd(MAT_TransposeMatMultNumeric,A,B,0,0);
 43:   return(0);
 44: }

 48: PetscErrorCode MatTransposeMatMultSymbolic_MPIAIJ_MPIDense(Mat A,Mat B,PetscReal fill,Mat *C)
 49: {
 50:   PetscErrorCode      ierr;
 51:   PetscInt            m=A->rmap->n,n=A->cmap->n,BN=B->cmap->N;
 52:   Mat_MatTransMatMult *atb;
 53:   Mat                 Cdense;
 54:   Vec                 bt,ct;
 55:   Mat_MPIDense        *c;
 56: 
 58:   PetscNew(&atb);

 60:   /* create output dense matrix C = A^T*B */
 61:   MatCreate(PetscObjectComm((PetscObject)A),&Cdense);
 62:   MatSetSizes(Cdense,n,PETSC_DECIDE,PETSC_DECIDE,BN);
 63:   MatSetType(Cdense,MATMPIDENSE);
 64:   MatMPIDenseSetPreallocation(Cdense,NULL);

 66:   /* create vectors bt and ct to hold locally transposed arrays of B and C */
 67:   VecCreate(PetscObjectComm((PetscObject)A),&bt);
 68:   VecSetSizes(bt,m*BN,PETSC_DECIDE);
 69:   VecSetType(bt,VECSTANDARD);
 70:   VecCreate(PetscObjectComm((PetscObject)A),&ct);
 71:   VecSetSizes(ct,n*BN,PETSC_DECIDE);
 72:   VecSetType(ct,VECSTANDARD);
 73:   atb->bt = bt;
 74:   atb->ct = ct;

 76:   *C = Cdense;
 77:   c                    = (Mat_MPIDense*)Cdense->data;
 78:   c->atb               = atb;
 79:   atb->destroy         = Cdense->ops->destroy;
 80:   Cdense->ops->destroy = MatDestroy_MPIDense_MatTransMatMult;
 81:   return(0);
 82: }

 86: PetscErrorCode MatTransposeMatMultNumeric_MPIAIJ_MPIDense(Mat A,Mat B,Mat C)
 87: {
 88:   PetscErrorCode      ierr;
 89:   PetscInt            i,j,k,m=A->rmap->n,n=A->cmap->n,BN=B->cmap->N;
 90:   PetscScalar         *Barray,*Carray,*btarray,*ctarray;
 91:   Mat_MPIDense        *c=(Mat_MPIDense*)C->data;
 92:   Mat_MatTransMatMult *atb=c->atb;
 93:   Vec                 bt=atb->bt,ct=atb->ct;

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

100:   /* transpose local arry of B, then copy it to vector bt */
101:   MatDenseGetArray(B,&Barray);
102:   VecGetArray(bt,&btarray);

104:   k=0;
105:   for (j=0; j<BN; j++) {
106:     for (i=0; i<m; i++) btarray[i*BN + j] = Barray[k++];
107:   }
108:   VecRestoreArray(bt,&btarray);
109:   MatDenseRestoreArray(B,&Barray);

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

114:   /* transpose local arry of ct to matrix C */
115:   MatDenseGetArray(C,&Carray);
116:   VecGetArray(ct,&ctarray);
117:   k = 0;
118:   for (j=0; j<BN; j++) {
119:     for (i=0; i<n; i++) Carray[k++] = ctarray[i*BN + j];
120:   }
121:   VecRestoreArray(ct,&ctarray);
122:   MatDenseRestoreArray(C,&Carray);
123:   MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
124:   MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);
125:   return(0);
126: }