Actual source code: aijbaij.c


  2: #include <../src/mat/impls/baij/seq/baij.h>

  4: PETSC_INTERN PetscErrorCode MatConvert_SeqBAIJ_SeqAIJ(Mat A, MatType newtype, MatReuse reuse, Mat *newmat)
  5: {
  6:   Mat          B;
  7:   Mat_SeqAIJ  *b;
  8:   PetscBool    roworiented;
  9:   Mat_SeqBAIJ *a  = (Mat_SeqBAIJ *)A->data;
 10:   PetscInt     bs = A->rmap->bs, *ai = a->i, *aj = a->j, n = A->rmap->N / bs, i, j, k;
 11:   PetscInt    *rowlengths, *rows, *cols, maxlen            = 0, ncols;
 12:   MatScalar   *aa = a->a;

 14:   PetscFunctionBegin;
 15:   if (reuse == MAT_REUSE_MATRIX) {
 16:     B = *newmat;
 17:     for (i = 0; i < n; i++) maxlen = PetscMax(maxlen, (ai[i + 1] - ai[i]));
 18:   } else {
 19:     PetscCall(PetscMalloc1(n * bs, &rowlengths));
 20:     for (i = 0; i < n; i++) {
 21:       maxlen = PetscMax(maxlen, (ai[i + 1] - ai[i]));
 22:       for (j = 0; j < bs; j++) rowlengths[i * bs + j] = bs * (ai[i + 1] - ai[i]);
 23:     }
 24:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
 25:     PetscCall(MatSetType(B, MATSEQAIJ));
 26:     PetscCall(MatSetSizes(B, A->rmap->n, A->cmap->n, A->rmap->N, A->cmap->N));
 27:     PetscCall(MatSetBlockSizes(B, A->rmap->bs, A->cmap->bs));
 28:     PetscCall(MatSeqAIJSetPreallocation(B, 0, rowlengths));
 29:     PetscCall(PetscFree(rowlengths));
 30:   }
 31:   b           = (Mat_SeqAIJ *)B->data;
 32:   roworiented = b->roworiented;

 34:   PetscCall(MatSetOption(B, MAT_ROW_ORIENTED, PETSC_FALSE));
 35:   PetscCall(PetscMalloc1(bs, &rows));
 36:   PetscCall(PetscMalloc1(bs * maxlen, &cols));
 37:   for (i = 0; i < n; i++) {
 38:     for (j = 0; j < bs; j++) rows[j] = i * bs + j;
 39:     ncols = ai[i + 1] - ai[i];
 40:     for (k = 0; k < ncols; k++) {
 41:       for (j = 0; j < bs; j++) cols[k * bs + j] = bs * (*aj) + j;
 42:       aj++;
 43:     }
 44:     PetscCall(MatSetValues(B, bs, rows, bs * ncols, cols, aa, INSERT_VALUES));
 45:     aa += ncols * bs * bs;
 46:   }
 47:   PetscCall(PetscFree(cols));
 48:   PetscCall(PetscFree(rows));
 49:   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
 50:   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
 51:   PetscCall(MatSetOption(B, MAT_ROW_ORIENTED, roworiented));

 53:   if (reuse == MAT_INPLACE_MATRIX) {
 54:     PetscCall(MatHeaderReplace(A, &B));
 55:   } else *newmat = B;
 56:   PetscFunctionReturn(PETSC_SUCCESS);
 57: }

 59: #include <../src/mat/impls/aij/seq/aij.h>

 61: PETSC_INTERN PetscErrorCode MatConvert_SeqAIJ_SeqBAIJ_Preallocate(Mat A, PetscInt **nnz)
 62: {
 63:   PetscInt    m, n, bs = PetscAbs(A->rmap->bs);
 64:   PetscInt   *ii;
 65:   Mat_SeqAIJ *Aa = (Mat_SeqAIJ *)A->data;

 67:   PetscFunctionBegin;
 68:   PetscCall(MatGetSize(A, &m, &n));
 69:   PetscCall(PetscCalloc1(m / bs, nnz));
 70:   PetscCall(PetscMalloc1(bs, &ii));

 72:   /* loop over all potential blocks in the matrix to see if the potential block has a nonzero */
 73:   for (PetscInt i = 0; i < m / bs; i++) {
 74:     for (PetscInt k = 0; k < bs; k++) ii[k] = Aa->i[i * bs + k];
 75:     for (PetscInt j = 0; j < n / bs; j++) {
 76:       for (PetscInt k = 0; k < bs; k++) {
 77:         for (; ii[k] < Aa->i[i * bs + k + 1] && Aa->j[ii[k]] < (j + 1) * bs; ii[k]++) {
 78:           if (Aa->j[ii[k]] >= j * bs) {
 79:             /* found a nonzero in the potential block so allocate for that block and jump to check the next potential block */
 80:             (*nnz)[i]++;
 81:             goto theend;
 82:           }
 83:         }
 84:       }
 85:     theend:;
 86:     }
 87:   }
 88:   PetscCall(PetscFree(ii));
 89:   PetscFunctionReturn(PETSC_SUCCESS);
 90: }

 92: PETSC_INTERN PetscErrorCode MatConvert_SeqAIJ_SeqBAIJ(Mat A, MatType newtype, MatReuse reuse, Mat *newmat)
 93: {
 94:   Mat          B;
 95:   Mat_SeqAIJ  *a = (Mat_SeqAIJ *)A->data;
 96:   Mat_SeqBAIJ *b;
 97:   PetscInt     m = A->rmap->N, n = A->cmap->N, *rowlengths, bs = PetscAbs(A->rmap->bs);

 99:   PetscFunctionBegin;
100:   if (reuse != MAT_REUSE_MATRIX) {
101:     PetscCall(MatConvert_SeqAIJ_SeqBAIJ_Preallocate(A, &rowlengths));
102:     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
103:     PetscCall(MatSetSizes(B, m, n, m, n));
104:     PetscCall(MatSetType(B, MATSEQBAIJ));
105:     PetscCall(MatSeqBAIJSetPreallocation(B, bs, 0, rowlengths));
106:     PetscCall(PetscFree(rowlengths));
107:   } else B = *newmat;

109:   if (bs == 1) {
110:     b = (Mat_SeqBAIJ *)(B->data);

112:     PetscCall(PetscArraycpy(b->i, a->i, m + 1));
113:     PetscCall(PetscArraycpy(b->ilen, a->ilen, m));
114:     PetscCall(PetscArraycpy(b->j, a->j, a->nz));
115:     PetscCall(PetscArraycpy(b->a, a->a, a->nz));

117:     PetscCall(MatSetOption(B, MAT_ROW_ORIENTED, PETSC_TRUE));
118:     PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
119:     PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
120:   } else {
121:     /* reuse may not be equal to MAT_REUSE_MATRIX, but the basic converter will reallocate or replace newmat if this value is not used */
122:     /* if reuse is equal to MAT_INITIAL_MATRIX, it has been appropriately preallocated before                                          */
123:     /*                      MAT_INPLACE_MATRIX, it will be replaced with MatHeaderReplace below                                        */
124:     PetscCall(MatConvert_Basic(A, newtype, MAT_REUSE_MATRIX, &B));
125:   }

127:   if (reuse == MAT_INPLACE_MATRIX) {
128:     PetscCall(MatHeaderReplace(A, &B));
129:   } else *newmat = B;
130:   PetscFunctionReturn(PETSC_SUCCESS);
131: }