xref: /petsc/src/mat/impls/aij/seq/mattransposematmult.c (revision c608a81790c32ca02bbec80504111e9e35bb0f8b)
1 
2 /*
3   Defines matrix-matrix product routines
4           C = A^T * B
5 */
6 
7 #include <../src/mat/impls/aij/seq/aij.h> /*I "petscmat.h" I*/
8 #include <../src/mat/impls/dense/seq/dense.h>
9 
10 #undef __FUNCT__
11 #define __FUNCT__ "MatDestroy_SeqDense_MatTransMatMult"
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;
17 
18   PetscFunctionBegin;
19   ierr = MatDestroy(&atb->mA);CHKERRQ(ierr);
20   ierr = VecDestroy(&atb->bt);CHKERRQ(ierr);
21   ierr = VecDestroy(&atb->ct);CHKERRQ(ierr);
22   ierr = (atb->destroy)(A);CHKERRQ(ierr);
23   ierr = PetscFree(atb);CHKERRQ(ierr);
24   PetscFunctionReturn(0);
25 }
26 
27 #undef __FUNCT__
28 #define __FUNCT__ "MatTransposeMatMult_SeqAIJ_SeqDense"
29 PetscErrorCode MatTransposeMatMult_SeqAIJ_SeqDense(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
30 {
31   PetscErrorCode ierr;
32 
33   PetscFunctionBegin;
34   if (scall == MAT_INITIAL_MATRIX) {
35     ierr = PetscLogEventBegin(MAT_TransposeMatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
36     ierr = MatTransposeMatMultSymbolic_SeqAIJ_SeqDense(A,B,fill,C);CHKERRQ(ierr);
37     ierr = PetscLogEventEnd(MAT_TransposeMatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
38   }
39   ierr = PetscLogEventBegin(MAT_TransposeMatMultNumeric,A,B,0,0);CHKERRQ(ierr);
40   ierr = MatTransposeMatMultNumeric_SeqAIJ_SeqDense(A,B,*C);CHKERRQ(ierr);
41   ierr = PetscLogEventEnd(MAT_TransposeMatMultNumeric,A,B,0,0);CHKERRQ(ierr);
42   PetscFunctionReturn(0);
43 }
44 
45 #undef __FUNCT__
46 #define __FUNCT__ "MatTransposeMatMultSymbolic_SeqAIJ_SeqDense"
47 PetscErrorCode MatTransposeMatMultSymbolic_SeqAIJ_SeqDense(Mat A,Mat B,PetscReal fill,Mat *C)
48 {
49   PetscErrorCode      ierr;
50   PetscInt            m,n,BN=B->cmap->N;
51   Mat_MatTransMatMult *atb;
52   Mat                 Cdense;
53   Vec                 bt,ct;
54   Mat_SeqDense        *c;
55 
56   PetscFunctionBegin;
57   ierr = PetscNew(Mat_MatTransMatMult,&atb);CHKERRQ(ierr);
58 
59   /* create output dense matrix C = A^T*B */
60   ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
61   ierr = MatCreate(PetscObjectComm((PetscObject)A),&Cdense);CHKERRQ(ierr);
62   ierr = MatSetSizes(Cdense,n,BN,n,BN);CHKERRQ(ierr);
63   ierr = MatSetType(Cdense,MATDENSE);CHKERRQ(ierr);
64   ierr = MatSeqDenseSetPreallocation(Cdense,NULL);CHKERRQ(ierr);
65 
66   /* create vectors bt and ct to hold locally transposed arrays of B and C */
67   ierr = VecCreate(PETSC_COMM_SELF,&bt);CHKERRQ(ierr);
68   ierr = VecSetSizes(bt,m*BN,m*BN);CHKERRQ(ierr);
69   ierr = VecSetFromOptions(bt);CHKERRQ(ierr);
70   ierr = VecCreate(PETSC_COMM_SELF,&ct);CHKERRQ(ierr);
71   ierr = VecSetSizes(ct,n*BN,n*BN);CHKERRQ(ierr);
72   ierr = VecSetFromOptions(ct);CHKERRQ(ierr);
73   atb->bt = bt;
74   atb->ct = ct;
75 
76   *C                   = Cdense;
77   c                    = (Mat_SeqDense*)Cdense->data;
78   c->atb               = atb;
79   atb->destroy         = Cdense->ops->destroy;
80   Cdense->ops->destroy = MatDestroy_SeqDense_MatTransMatMult;
81   PetscFunctionReturn(0);
82 }
83 
84 #undef __FUNCT__
85 #define __FUNCT__ "MatTransposeMatMultNumeric_SeqAIJ_SeqDense"
86 PetscErrorCode MatTransposeMatMultNumeric_SeqAIJ_SeqDense(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_SeqDense        *c=(Mat_SeqDense*)C->data;
92   Mat_MatTransMatMult *atb=c->atb;
93   Vec                 bt=atb->bt,ct=atb->ct;
94 
95   PetscFunctionBegin;
96   //ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
97 
98   /* create MAIJ matrix mA from A -- should be done in symbolic phase */
99   ierr = MatDestroy(&atb->mA);CHKERRQ(ierr);
100   ierr = MatCreateMAIJ(A,BN,&atb->mA);CHKERRQ(ierr);
101 
102   /* transpose local arry of B, then copy it to vector bt */
103   ierr = MatDenseGetArray(B,&Barray);CHKERRQ(ierr);
104   ierr = VecGetArray(bt,&btarray);CHKERRQ(ierr);
105 
106   k=0;
107   for (j=0; j<BN; j++) {
108     for (i=0; i<m; i++) btarray[i*BN + j] = Barray[k++];
109   }
110   ierr = VecRestoreArray(bt,&btarray);CHKERRQ(ierr);
111   ierr = MatDenseRestoreArray(B,&Barray);CHKERRQ(ierr);
112 
113   /* compute ct = mA^T * cb */
114   ierr = MatMultTranspose(atb->mA,bt,ct);CHKERRQ(ierr);
115 
116   /* transpose local arry of ct to matrix C */
117   ierr = MatDenseGetArray(C,&Carray);CHKERRQ(ierr);
118   ierr = VecGetArray(ct,&ctarray);CHKERRQ(ierr);
119   k = 0;
120   for (j=0; j<BN; j++) {
121     for (i=0; i<n; i++) Carray[k++] = ctarray[i*BN + j];
122   }
123   ierr = VecRestoreArray(ct,&ctarray);CHKERRQ(ierr);
124   ierr = MatDenseRestoreArray(C,&Carray);CHKERRQ(ierr);
125   PetscFunctionReturn(0);
126 }
127