2: /*
  3:   Defines matrix-matrix product routines 
  4:           C = A^T * B
  5: */

  7: #include <../src/mat/impls/aij/seq/aij.h> /*I "petscmat.h" I*/
  8: #include <../src/mat/impls/dense/seq/dense.h>

 12: PetscErrorCode MatDestroy_SeqDense_MatTransMatMult(Mat A)
 13: {
 14:   PetscErrorCode      ierr;
 15:   Mat_SeqDense        *a = (Mat_SeqDense*)A->data;
 16:   Mat_MatTransMatMult *atb = a->atb;

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

 29: PetscErrorCode MatTransposeMatMult_SeqAIJ_SeqDense(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
 30: {
 32: 
 34:   if (scall == MAT_INITIAL_MATRIX) {
 35:     PetscLogEventBegin(MAT_TransposeMatMultSymbolic,A,B,0,0);
 36:     MatTransposeMatMultSymbolic_SeqAIJ_SeqDense(A,B,fill,C);
 37:     PetscLogEventEnd(MAT_TransposeMatMultSymbolic,A,B,0,0);
 38:   }
 39:   PetscLogEventBegin(MAT_TransposeMatMultNumeric,A,B,0,0);
 40:   MatTransposeMatMultNumeric_SeqAIJ_SeqDense(A,B,*C);
 41:   PetscLogEventEnd(MAT_TransposeMatMultNumeric,A,B,0,0);
 42:   return(0);
 43: }

 47: PetscErrorCode MatTransposeMatMultSymbolic_SeqAIJ_SeqDense(Mat A,Mat B,PetscReal fill,Mat *C)
 48: {
 49:   PetscErrorCode      ierr;
 50:   PetscInt            m=A->rmap->n,n=A->cmap->n,BN=B->cmap->N;
 51:   Mat_MatTransMatMult *atb;
 52:   Mat                 Cdense;
 53:   Vec                 bt,ct;
 54:   Mat_SeqDense        *c;

 57:   PetscNew(&atb);

 59:   /* create output dense matrix C = A^T*B */
 60:   MatCreate(PETSC_COMM_SELF,&Cdense);
 61:   MatSetSizes(Cdense,n,BN,n,BN);
 62:   MatSetType(Cdense,MATSEQDENSE);
 63:   MatSeqDenseSetPreallocation(Cdense,NULL);

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

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

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

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

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

103:   k=0;
104:   for (j=0; j<BN; j++) {
105:     for (i=0; i<m; i++) btarray[i*BN + j] = Barray[k++];
106:   }
107:   VecRestoreArray(bt,&btarray);
108:   MatDenseRestoreArray(B,&Barray);
109: 
110:   /* compute ct = mA^T * cb */
111:   MatMultTranspose(atb->mA,bt,ct);

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