xref: /petsc/src/mat/impls/sbaij/seq/aijsbaij.c (revision 74ee4d9fbf84f6eaa2badda2caf9888cc060086a)
1be1d678aSKris Buschelman #define PETSCMAT_DLL
259557b74SHong Zhang 
37c4f633dSBarry Smith #include "../src/mat/impls/aij/seq/aij.h"
47c4f633dSBarry Smith #include "../src/mat/impls/baij/seq/baij.h"
57c4f633dSBarry Smith #include "../src/mat/impls/sbaij/seq/sbaij.h"
659557b74SHong Zhang 
759557b74SHong Zhang EXTERN_C_BEGIN
859557b74SHong Zhang #undef __FUNCT__
94124e67cSShri Abhyankar #define __FUNCT__ "MatConvert_SeqSBAIJ_SeqAIJ"
10f69a0ea3SMatthew Knepley PetscErrorCode PETSCMAT_DLLEXPORT MatConvert_SeqSBAIJ_SeqAIJ(Mat A, MatType newtype,MatReuse reuse,Mat *newmat)
114e5e7fe4SHong Zhang {
124e5e7fe4SHong Zhang   Mat            B;
134e5e7fe4SHong Zhang   Mat_SeqSBAIJ   *a = (Mat_SeqSBAIJ*)A->data;
144e5e7fe4SHong Zhang   Mat_SeqAIJ     *b;
15dfbe8321SBarry Smith   PetscErrorCode ierr;
16d0f46423SBarry Smith   PetscInt       *ai=a->i,*aj=a->j,m=A->rmap->N,n=A->cmap->n,i,j,k,*bi,*bj,*rowlengths,nz,*rowstart,itmp;
1701be0148SBarry Smith   PetscInt       bs=A->rmap->bs,bs2=bs*bs,mbs=A->rmap->N/bs,diagcnt=0;
18dd6ea824SBarry Smith   MatScalar      *av,*bv;
194e5e7fe4SHong Zhang 
204e5e7fe4SHong Zhang   PetscFunctionBegin;
214e5e7fe4SHong Zhang   /* compute rowlengths of newmat */
2274ed9c26SBarry Smith   ierr = PetscMalloc2(m,PetscInt,&rowlengths,m+1,PetscInt,&rowstart);CHKERRQ(ierr);
23a7a3a9ebSHong Zhang 
24a7a3a9ebSHong Zhang   for (i=0; i<mbs; i++) rowlengths[i*bs] = 0;
254e5e7fe4SHong Zhang   aj = a->j;
26a7a3a9ebSHong Zhang   k = 0;
27a7a3a9ebSHong Zhang   for (i=0; i<mbs; i++) {
284e5e7fe4SHong Zhang     nz = ai[i+1] - ai[i];
2901be0148SBarry Smith     if (nz) {
3001be0148SBarry Smith       rowlengths[k] += nz;   /* no. of upper triangular blocks */
3101be0148SBarry Smith       if (*aj == i) {aj++;diagcnt++;nz--;} /* skip diagonal */
3201be0148SBarry Smith       for (j=0; j<nz; j++) { /* no. of lower triangular blocks */
33a7a3a9ebSHong Zhang 	rowlengths[(*aj)*bs]++; aj++;
34a7a3a9ebSHong Zhang       }
3501be0148SBarry Smith     }
36a7a3a9ebSHong Zhang     rowlengths[k] *= bs;
37a7a3a9ebSHong Zhang     for (j=1; j<bs; j++) {
38a7a3a9ebSHong Zhang       rowlengths[k+j] = rowlengths[k];
39a7a3a9ebSHong Zhang     }
40a7a3a9ebSHong Zhang     k += bs;
41a7a3a9ebSHong Zhang     /* printf(" rowlengths[%d]: %d\n",i, rowlengths[i]); */
424e5e7fe4SHong Zhang   }
434e5e7fe4SHong Zhang 
447adad957SLisandro Dalcin   ierr = MatCreate(((PetscObject)A)->comm,&B);CHKERRQ(ierr);
45f69a0ea3SMatthew Knepley   ierr = MatSetSizes(B,m,n,m,n);CHKERRQ(ierr);
46f204ca49SKris Buschelman   ierr = MatSetType(B,newtype);CHKERRQ(ierr);
47f204ca49SKris Buschelman   ierr = MatSeqAIJSetPreallocation(B,0,rowlengths);CHKERRQ(ierr);
484e0d8c25SBarry Smith   ierr = MatSetOption(B,MAT_ROW_ORIENTED,PETSC_FALSE);CHKERRQ(ierr);
49d0f46423SBarry Smith   B->rmap->bs = A->rmap->bs;
504e5e7fe4SHong Zhang 
514e5e7fe4SHong Zhang   b  = (Mat_SeqAIJ*)(B->data);
524e5e7fe4SHong Zhang   bi = b->i;
534e5e7fe4SHong Zhang   bj = b->j;
544e5e7fe4SHong Zhang   bv = b->a;
554e5e7fe4SHong Zhang 
564e5e7fe4SHong Zhang   /* set b->i */
57a7a3a9ebSHong Zhang   bi[0] = 0; rowstart[0] = 0;
58a7a3a9ebSHong Zhang   for (i=0; i<mbs; i++){
59a7a3a9ebSHong Zhang     for (j=0; j<bs; j++){
60a7a3a9ebSHong Zhang       b->ilen[i*bs+j]    = rowlengths[i*bs];
61a7a3a9ebSHong Zhang       rowstart[i*bs+j+1] = rowstart[i*bs+j] + rowlengths[i*bs];
624e5e7fe4SHong Zhang     }
63a7a3a9ebSHong Zhang     bi[i+1]     = bi[i] + rowlengths[i*bs]/bs;
64a7a3a9ebSHong Zhang   }
6501be0148SBarry Smith   if (bi[mbs] != 2*a->nz - diagcnt) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"bi[mbs]: %D != 2*a->nz-diagcnt: %D\n",bi[mbs],2*a->nz - diagcnt);
664e5e7fe4SHong Zhang 
674e5e7fe4SHong Zhang   /* set b->j and b->a */
684e5e7fe4SHong Zhang   aj = a->j; av = a->a;
69a7a3a9ebSHong Zhang   for (i=0; i<mbs; i++) {
7001be0148SBarry Smith     nz = ai[i+1] - ai[i];
71a7a3a9ebSHong Zhang     /* diagonal block */
7201be0148SBarry Smith     if (nz && *aj == i) {
7301be0148SBarry Smith       nz--;
74a7a3a9ebSHong Zhang       for (j=0; j<bs; j++){   /* row i*bs+j */
75a7a3a9ebSHong Zhang 	itmp = i*bs+j;
76a7a3a9ebSHong Zhang 	for (k=0; k<bs; k++){ /* col i*bs+k */
77a7a3a9ebSHong Zhang 	  *(bj + rowstart[itmp]) = (*aj)*bs+k;
78a7a3a9ebSHong Zhang 	  *(bv + rowstart[itmp]) = *(av+k*bs+j);
79a7a3a9ebSHong Zhang 	  rowstart[itmp]++;
80a7a3a9ebSHong Zhang 	}
81a7a3a9ebSHong Zhang       }
82a7a3a9ebSHong Zhang       aj++; av += bs2;
8301be0148SBarry Smith     }
84a7a3a9ebSHong Zhang 
854e5e7fe4SHong Zhang     while (nz--){
86a7a3a9ebSHong Zhang       /* lower triangular blocks */
87a7a3a9ebSHong Zhang       for (j=0; j<bs; j++){   /* row (*aj)*bs+j */
88a7a3a9ebSHong Zhang         itmp = (*aj)*bs+j;
89a7a3a9ebSHong Zhang         for (k=0; k<bs; k++){ /* col i*bs+k */
90a7a3a9ebSHong Zhang           *(bj + rowstart[itmp]) = i*bs+k;
913bededecSBarry Smith           *(bv + rowstart[itmp]) = *(av+j*bs+k);
92a7a3a9ebSHong Zhang           rowstart[itmp]++;
93a7a3a9ebSHong Zhang         }
94a7a3a9ebSHong Zhang       }
95a7a3a9ebSHong Zhang       /* upper triangular blocks */
96a7a3a9ebSHong Zhang       for (j=0; j<bs; j++){   /* row i*bs+j */
97a7a3a9ebSHong Zhang         itmp = i*bs+j;
98a7a3a9ebSHong Zhang         for (k=0; k<bs; k++){ /* col (*aj)*bs+k */
99a7a3a9ebSHong Zhang           *(bj + rowstart[itmp]) = (*aj)*bs+k;
100a7a3a9ebSHong Zhang           *(bv + rowstart[itmp]) = *(av+k*bs+j);
101a7a3a9ebSHong Zhang           rowstart[itmp]++;
102a7a3a9ebSHong Zhang         }
103a7a3a9ebSHong Zhang       }
104a7a3a9ebSHong Zhang       aj++; av += bs2;
1054e5e7fe4SHong Zhang     }
1064e5e7fe4SHong Zhang   }
10774ed9c26SBarry Smith   ierr = PetscFree2(rowlengths,rowstart);CHKERRQ(ierr);
1084e5e7fe4SHong Zhang   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1094e5e7fe4SHong Zhang   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1104e5e7fe4SHong Zhang 
111ceb03754SKris Buschelman   if (reuse == MAT_REUSE_MATRIX) {
1128ab5b326SKris Buschelman     ierr = MatHeaderReplace(A,B);CHKERRQ(ierr);
113c3d102feSKris Buschelman   } else {
1144e5e7fe4SHong Zhang     *newmat = B;
115c3d102feSKris Buschelman   }
1164e5e7fe4SHong Zhang   PetscFunctionReturn(0);
1174e5e7fe4SHong Zhang }
118be1d678aSKris Buschelman EXTERN_C_END
119be1d678aSKris Buschelman 
120be1d678aSKris Buschelman EXTERN_C_BEGIN
1214e5e7fe4SHong Zhang #undef __FUNCT__
12259557b74SHong Zhang #define __FUNCT__ "MatConvert_SeqAIJ_SeqSBAIJ"
1238cf70c4bSSatish Balay PetscErrorCode PETSCMAT_DLLEXPORT MatConvert_SeqAIJ_SeqSBAIJ(Mat A,const MatType newtype,MatReuse reuse,Mat *newmat) {
124676c34cdSKris Buschelman   Mat            B;
12559557b74SHong Zhang   Mat_SeqAIJ     *a = (Mat_SeqAIJ*)A->data;
126861ba921SHong Zhang   Mat_SeqSBAIJ   *b;
127dfbe8321SBarry Smith   PetscErrorCode ierr;
128d0f46423SBarry Smith   PetscInt       *ai=a->i,*aj,m=A->rmap->N,n=A->cmap->N,i,j,*bi,*bj,*rowlengths;
129dd6ea824SBarry Smith   MatScalar      *av,*bv;
13059557b74SHong Zhang 
13159557b74SHong Zhang   PetscFunctionBegin;
132e32f2f54SBarry Smith   if (n != m) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Matrix must be square");
13359557b74SHong Zhang 
13413f74950SBarry Smith   ierr = PetscMalloc(m*sizeof(PetscInt),&rowlengths);CHKERRQ(ierr);
13559557b74SHong Zhang   for (i=0; i<m; i++) {
13659557b74SHong Zhang     rowlengths[i] = ai[i+1] - a->diag[i];
13759557b74SHong Zhang   }
1387adad957SLisandro Dalcin   ierr = MatCreate(((PetscObject)A)->comm,&B);CHKERRQ(ierr);
139f69a0ea3SMatthew Knepley   ierr = MatSetSizes(B,m,n,m,n);CHKERRQ(ierr);
140f204ca49SKris Buschelman   ierr = MatSetType(B,newtype);CHKERRQ(ierr);
141ab93d7beSBarry Smith   ierr = MatSeqSBAIJSetPreallocation_SeqSBAIJ(B,1,0,rowlengths);CHKERRQ(ierr);
14259557b74SHong Zhang 
1434e0d8c25SBarry Smith   ierr = MatSetOption(B,MAT_ROW_ORIENTED,PETSC_TRUE);CHKERRQ(ierr);
14459557b74SHong Zhang 
145676c34cdSKris Buschelman   b  = (Mat_SeqSBAIJ*)(B->data);
146861ba921SHong Zhang   bi = b->i;
147861ba921SHong Zhang   bj = b->j;
148861ba921SHong Zhang   bv = b->a;
149861ba921SHong Zhang 
150861ba921SHong Zhang   bi[0] = 0;
15159557b74SHong Zhang   for (i=0; i<m; i++) {
15259557b74SHong Zhang     aj = a->j + a->diag[i];
15359557b74SHong Zhang     av = a->a + a->diag[i];
154861ba921SHong Zhang     for (j=0; j<rowlengths[i]; j++){
155861ba921SHong Zhang       *bj = *aj; bj++; aj++;
156861ba921SHong Zhang       *bv = *av; bv++; av++;
157861ba921SHong Zhang     }
158861ba921SHong Zhang     bi[i+1]    = bi[i] + rowlengths[i];
159861ba921SHong Zhang     b->ilen[i] = rowlengths[i];
16059557b74SHong Zhang   }
16159557b74SHong Zhang 
16259557b74SHong Zhang   ierr = PetscFree(rowlengths);CHKERRQ(ierr);
163676c34cdSKris Buschelman   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
164676c34cdSKris Buschelman   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
165eeffb40dSHong Zhang   if (A->hermitian){
166eeffb40dSHong Zhang     ierr = MatSetOption(B,MAT_HERMITIAN,PETSC_TRUE);CHKERRQ(ierr);
167eeffb40dSHong Zhang   }
168676c34cdSKris Buschelman 
169ceb03754SKris Buschelman   if (reuse == MAT_REUSE_MATRIX) {
1708ab5b326SKris Buschelman     ierr = MatHeaderReplace(A,B);CHKERRQ(ierr);
171c3d102feSKris Buschelman   } else {
172676c34cdSKris Buschelman     *newmat = B;
173c3d102feSKris Buschelman   }
17459557b74SHong Zhang   PetscFunctionReturn(0);
17559557b74SHong Zhang }
17659557b74SHong Zhang EXTERN_C_END
17759557b74SHong Zhang 
178a0e1a404SHong Zhang EXTERN_C_BEGIN
179a0e1a404SHong Zhang #undef __FUNCT__
1807af9e4fdSHong Zhang #define __FUNCT__ "MatConvert_SeqSBAIJ_SeqBAIJ"
181f69a0ea3SMatthew Knepley PetscErrorCode PETSCMAT_DLLEXPORT MatConvert_SeqSBAIJ_SeqBAIJ(Mat A, MatType newtype,MatReuse reuse,Mat *newmat)
182a0e1a404SHong Zhang {
183a0e1a404SHong Zhang   Mat            B;
184a0e1a404SHong Zhang   Mat_SeqSBAIJ   *a = (Mat_SeqSBAIJ*)A->data;
185a0e1a404SHong Zhang   Mat_SeqBAIJ    *b;
186dfbe8321SBarry Smith   PetscErrorCode ierr;
187d0f46423SBarry Smith   PetscInt       *ai=a->i,*aj=a->j,m=A->rmap->N,n=A->cmap->n,i,k,*bi,*bj,*browlengths,nz,*browstart,itmp;
188*74ee4d9fSHong Zhang   PetscInt       bs=A->rmap->bs,bs2=bs*bs,mbs=m/bs,col,row;
189dd6ea824SBarry Smith   MatScalar      *av,*bv;
190a0e1a404SHong Zhang 
191a0e1a404SHong Zhang   PetscFunctionBegin;
192a0e1a404SHong Zhang   /* compute browlengths of newmat */
19374ed9c26SBarry Smith   ierr = PetscMalloc2(mbs,PetscInt,&browlengths,mbs,PetscInt,&browstart);CHKERRQ(ierr);
194a0e1a404SHong Zhang   for (i=0; i<mbs; i++) browlengths[i] = 0;
195a0e1a404SHong Zhang   aj = a->j;
196a0e1a404SHong Zhang   for (i=0; i<mbs; i++) {
197a0e1a404SHong Zhang     nz = ai[i+1] - ai[i];
198a0e1a404SHong Zhang     aj++; /* skip diagonal */
199a0e1a404SHong Zhang     for (k=1; k<nz; k++) { /* no. of lower triangular blocks */
200a0e1a404SHong Zhang       browlengths[*aj]++; aj++;
201a0e1a404SHong Zhang     }
202a0e1a404SHong Zhang     browlengths[i] += nz;   /* no. of upper triangular blocks */
203a0e1a404SHong Zhang   }
204a0e1a404SHong Zhang 
2057adad957SLisandro Dalcin   ierr = MatCreate(((PetscObject)A)->comm,&B);CHKERRQ(ierr);
206f69a0ea3SMatthew Knepley   ierr = MatSetSizes(B,m,n,m,n);CHKERRQ(ierr);
207f204ca49SKris Buschelman   ierr = MatSetType(B,newtype);CHKERRQ(ierr);
208f204ca49SKris Buschelman   ierr = MatSeqBAIJSetPreallocation(B,bs,0,browlengths);CHKERRQ(ierr);
2094e0d8c25SBarry Smith   ierr = MatSetOption(B,MAT_ROW_ORIENTED,PETSC_TRUE);CHKERRQ(ierr);
210a0e1a404SHong Zhang 
211a0e1a404SHong Zhang   b  = (Mat_SeqBAIJ*)(B->data);
212a0e1a404SHong Zhang   bi = b->i;
213a0e1a404SHong Zhang   bj = b->j;
214a0e1a404SHong Zhang   bv = b->a;
215a0e1a404SHong Zhang 
216a0e1a404SHong Zhang   /* set b->i */
217a0e1a404SHong Zhang   bi[0] = 0;
218a0e1a404SHong Zhang   for (i=0; i<mbs; i++){
219a0e1a404SHong Zhang     b->ilen[i]   = browlengths[i];
220a0e1a404SHong Zhang     bi[i+1]      = bi[i] + browlengths[i];
221a0e1a404SHong Zhang     browstart[i] = bi[i];
222a0e1a404SHong Zhang   }
223e32f2f54SBarry Smith   if (bi[mbs] != 2*a->nz - mbs) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"bi[mbs]: %D != 2*a->nz - mbs: %D\n",bi[mbs],2*a->nz - mbs);
224a0e1a404SHong Zhang 
225a0e1a404SHong Zhang   /* set b->j and b->a */
226a0e1a404SHong Zhang   aj = a->j; av = a->a;
227a0e1a404SHong Zhang   for (i=0; i<mbs; i++) {
228a0e1a404SHong Zhang     /* diagonal block */
229a0e1a404SHong Zhang     *(bj + browstart[i]) = *aj; aj++;
230a0e1a404SHong Zhang     itmp = bs2*browstart[i];
231a0e1a404SHong Zhang     for (k=0; k<bs2; k++){
232a0e1a404SHong Zhang       *(bv + itmp + k) = *av; av++;
233a0e1a404SHong Zhang     }
234a0e1a404SHong Zhang     browstart[i]++;
235a0e1a404SHong Zhang 
236a0e1a404SHong Zhang     nz = ai[i+1] - ai[i] -1;
237a0e1a404SHong Zhang     while (nz--){
238*74ee4d9fSHong Zhang       /* lower triangular blocks - transpose blocks of A */
239*74ee4d9fSHong Zhang       *(bj + browstart[*aj]) = i; /* block col index */
240*74ee4d9fSHong Zhang       itmp = bs2*browstart[*aj];  /* row index */
241*74ee4d9fSHong Zhang       for (col=0; col<bs; col++){
242*74ee4d9fSHong Zhang         k = col;
243*74ee4d9fSHong Zhang         for (row=0; row<bs; row++){
244*74ee4d9fSHong Zhang           bv[itmp + col*bs+row] = av[k]; k+=bs;
245*74ee4d9fSHong Zhang         }
246a0e1a404SHong Zhang       }
247a0e1a404SHong Zhang       browstart[*aj]++;
248a0e1a404SHong Zhang 
249a0e1a404SHong Zhang       /* upper triangular blocks */
250a0e1a404SHong Zhang       *(bj + browstart[i]) = *aj; aj++;
251a0e1a404SHong Zhang       itmp = bs2*browstart[i];
252a0e1a404SHong Zhang       for (k=0; k<bs2; k++){
253*74ee4d9fSHong Zhang         bv[itmp + k] = av[k];
254a0e1a404SHong Zhang       }
255*74ee4d9fSHong Zhang       av += bs2;
256a0e1a404SHong Zhang       browstart[i]++;
257a0e1a404SHong Zhang     }
258a0e1a404SHong Zhang   }
25974ed9c26SBarry Smith   ierr = PetscFree2(browlengths,browstart);CHKERRQ(ierr);
260a0e1a404SHong Zhang   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
261a0e1a404SHong Zhang   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
262a0e1a404SHong Zhang 
263ceb03754SKris Buschelman   if (reuse == MAT_REUSE_MATRIX) {
2648ab5b326SKris Buschelman     ierr = MatHeaderReplace(A,B);CHKERRQ(ierr);
265c3d102feSKris Buschelman   } else {
266a0e1a404SHong Zhang     *newmat = B;
267c3d102feSKris Buschelman   }
268a0e1a404SHong Zhang   PetscFunctionReturn(0);
269a0e1a404SHong Zhang }
270be1d678aSKris Buschelman EXTERN_C_END
271be1d678aSKris Buschelman 
272be1d678aSKris Buschelman EXTERN_C_BEGIN
273a0e1a404SHong Zhang #undef __FUNCT__
274a0e1a404SHong Zhang #define __FUNCT__ "MatConvert_SeqBAIJ_SeqSBAIJ"
275f69a0ea3SMatthew Knepley PetscErrorCode PETSCMAT_DLLEXPORT MatConvert_SeqBAIJ_SeqSBAIJ(Mat A, MatType newtype,MatReuse reuse,Mat *newmat)
276a0e1a404SHong Zhang {
277a0e1a404SHong Zhang   Mat            B;
278a0e1a404SHong Zhang   Mat_SeqBAIJ    *a = (Mat_SeqBAIJ*)A->data;
279a0e1a404SHong Zhang   Mat_SeqSBAIJ   *b;
280dfbe8321SBarry Smith   PetscErrorCode ierr;
281d0f46423SBarry Smith   PetscInt       *ai=a->i,*aj,m=A->rmap->N,n=A->cmap->n,i,j,k,*bi,*bj,*browlengths;
282d0f46423SBarry Smith   PetscInt       bs=A->rmap->bs,bs2=bs*bs,mbs=m/bs,dd;
283dd6ea824SBarry Smith   MatScalar      *av,*bv;
284ace3abfcSBarry Smith   PetscBool      flg;
285a0e1a404SHong Zhang 
286a0e1a404SHong Zhang   PetscFunctionBegin;
287e32f2f54SBarry Smith   if (n != m) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Matrix must be square");
2882af78befSBarry Smith   ierr = MatMissingDiagonal_SeqBAIJ(A,&flg,&dd);CHKERRQ(ierr); /* check for missing diagonals, then mark diag */
289e32f2f54SBarry Smith   if (flg) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Matrix is missing diagonal %D",dd);
290a0e1a404SHong Zhang 
29113f74950SBarry Smith   ierr = PetscMalloc(mbs*sizeof(PetscInt),&browlengths);CHKERRQ(ierr);
292a0e1a404SHong Zhang   for (i=0; i<mbs; i++) {
293a0e1a404SHong Zhang     browlengths[i] = ai[i+1] - a->diag[i];
294a0e1a404SHong Zhang   }
295a0e1a404SHong Zhang 
2967adad957SLisandro Dalcin   ierr = MatCreate(((PetscObject)A)->comm,&B);CHKERRQ(ierr);
297f69a0ea3SMatthew Knepley   ierr = MatSetSizes(B,m,n,m,n);CHKERRQ(ierr);
298f204ca49SKris Buschelman   ierr = MatSetType(B,newtype);CHKERRQ(ierr);
299ab93d7beSBarry Smith   ierr = MatSeqSBAIJSetPreallocation_SeqSBAIJ(B,bs,0,browlengths);CHKERRQ(ierr);
3004e0d8c25SBarry Smith   ierr = MatSetOption(B,MAT_ROW_ORIENTED,PETSC_TRUE);CHKERRQ(ierr);
301a0e1a404SHong Zhang 
302a0e1a404SHong Zhang   b  = (Mat_SeqSBAIJ*)(B->data);
303a0e1a404SHong Zhang   bi = b->i;
304a0e1a404SHong Zhang   bj = b->j;
305a0e1a404SHong Zhang   bv = b->a;
306a0e1a404SHong Zhang 
307a0e1a404SHong Zhang   bi[0] = 0;
308a0e1a404SHong Zhang   for (i=0; i<mbs; i++) {
309a0e1a404SHong Zhang     aj = a->j + a->diag[i];
310a0e1a404SHong Zhang     av = a->a + (a->diag[i])*bs2;
311a0e1a404SHong Zhang     for (j=0; j<browlengths[i]; j++){
312a0e1a404SHong Zhang       *bj = *aj; bj++; aj++;
313a0e1a404SHong Zhang       for (k=0; k<bs2; k++){
314a0e1a404SHong Zhang         *bv = *av; bv++; av++;
315a0e1a404SHong Zhang       }
316a0e1a404SHong Zhang     }
317a0e1a404SHong Zhang     bi[i+1]    = bi[i] + browlengths[i];
318a0e1a404SHong Zhang     b->ilen[i] = browlengths[i];
319a0e1a404SHong Zhang   }
320a0e1a404SHong Zhang   ierr = PetscFree(browlengths);CHKERRQ(ierr);
321a0e1a404SHong Zhang   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
322a0e1a404SHong Zhang   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
323a0e1a404SHong Zhang 
324ceb03754SKris Buschelman   if (reuse == MAT_REUSE_MATRIX) {
3258ab5b326SKris Buschelman     ierr = MatHeaderReplace(A,B);CHKERRQ(ierr);
326c3d102feSKris Buschelman   } else {
327a0e1a404SHong Zhang     *newmat = B;
328c3d102feSKris Buschelman   }
329a0e1a404SHong Zhang 
330a0e1a404SHong Zhang   PetscFunctionReturn(0);
331a0e1a404SHong Zhang }
332a0e1a404SHong Zhang EXTERN_C_END
333