xref: /petsc/src/mat/impls/sbaij/seq/aijsbaij.c (revision f13dfd9ea68e0ddeee984e65c377a1819eab8a8a)
1 #include <../src/mat/impls/aij/seq/aij.h>
2 #include <../src/mat/impls/baij/seq/baij.h>
3 #include <../src/mat/impls/sbaij/seq/sbaij.h>
4 
5 PETSC_INTERN PetscErrorCode MatConvert_SeqSBAIJ_SeqAIJ(Mat A, MatType newtype, MatReuse reuse, Mat *newmat)
6 {
7   Mat           B;
8   Mat_SeqSBAIJ *a = (Mat_SeqSBAIJ *)A->data;
9   Mat_SeqAIJ   *b;
10   PetscInt     *ai = a->i, *aj = a->j, m = A->rmap->N, n = A->cmap->n, i, j, k, *bi, *bj, *rowlengths, nz, *rowstart, itmp;
11   PetscInt      bs = A->rmap->bs, bs2 = bs * bs, mbs = A->rmap->N / bs, diagcnt = 0;
12   MatScalar    *av, *bv;
13 #if defined(PETSC_USE_COMPLEX)
14   const int aconj = A->hermitian == PETSC_BOOL3_TRUE ? 1 : 0;
15 #else
16   const int aconj = 0;
17 #endif
18 
19   PetscFunctionBegin;
20   /* compute rowlengths of newmat */
21   PetscCall(PetscMalloc2(m, &rowlengths, m + 1, &rowstart));
22 
23   for (i = 0; i < mbs; i++) rowlengths[i * bs] = 0;
24   k = 0;
25   for (i = 0; i < mbs; i++) {
26     nz = ai[i + 1] - ai[i];
27     if (nz) {
28       rowlengths[k] += nz; /* no. of upper triangular blocks */
29       if (*aj == i) {
30         aj++;
31         diagcnt++;
32         nz--;
33       } /* skip diagonal */
34       for (j = 0; j < nz; j++) { /* no. of lower triangular blocks */
35         rowlengths[(*aj) * bs]++;
36         aj++;
37       }
38     }
39     rowlengths[k] *= bs;
40     for (j = 1; j < bs; j++) rowlengths[k + j] = rowlengths[k];
41     k += bs;
42   }
43 
44   if (reuse != MAT_REUSE_MATRIX) {
45     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
46     PetscCall(MatSetSizes(B, m, n, m, n));
47     PetscCall(MatSetType(B, MATSEQAIJ));
48     PetscCall(MatSeqAIJSetPreallocation(B, 0, rowlengths));
49     PetscCall(MatSetBlockSize(B, A->rmap->bs));
50   } else B = *newmat;
51 
52   b  = (Mat_SeqAIJ *)B->data;
53   bi = b->i;
54   bj = b->j;
55   bv = b->a;
56 
57   /* set b->i */
58   bi[0]       = 0;
59   rowstart[0] = 0;
60   for (i = 0; i < mbs; i++) {
61     for (j = 0; j < bs; j++) {
62       b->ilen[i * bs + j]      = rowlengths[i * bs];
63       rowstart[i * bs + j + 1] = rowstart[i * bs + j] + rowlengths[i * bs];
64     }
65     bi[i + 1] = bi[i] + rowlengths[i * bs] / bs;
66   }
67   PetscCheck(bi[mbs] == 2 * a->nz - diagcnt, PETSC_COMM_SELF, PETSC_ERR_PLIB, "bi[mbs]: %" PetscInt_FMT " != 2*a->nz-diagcnt: %" PetscInt_FMT, bi[mbs], 2 * a->nz - diagcnt);
68 
69   /* set b->j and b->a */
70   aj = a->j;
71   av = a->a;
72   for (i = 0; i < mbs; i++) {
73     nz = ai[i + 1] - ai[i];
74     /* diagonal block */
75     if (nz && *aj == i) {
76       nz--;
77       for (j = 0; j < bs; j++) { /* row i*bs+j */
78         itmp = i * bs + j;
79         for (k = 0; k < bs; k++) { /* col i*bs+k */
80           *(bj + rowstart[itmp]) = (*aj) * bs + k;
81           *(bv + rowstart[itmp]) = *(av + k * bs + j);
82           rowstart[itmp]++;
83         }
84       }
85       aj++;
86       av += bs2;
87     }
88 
89     while (nz--) {
90       /* lower triangular blocks */
91       for (j = 0; j < bs; j++) { /* row (*aj)*bs+j */
92         itmp = (*aj) * bs + j;
93         for (k = 0; k < bs; k++) { /* col i*bs+k */
94           *(bj + rowstart[itmp]) = i * bs + k;
95           *(bv + rowstart[itmp]) = aconj ? PetscConj(*(av + j * bs + k)) : *(av + j * bs + k);
96           rowstart[itmp]++;
97         }
98       }
99       /* upper triangular blocks */
100       for (j = 0; j < bs; j++) { /* row i*bs+j */
101         itmp = i * bs + j;
102         for (k = 0; k < bs; k++) { /* col (*aj)*bs+k */
103           *(bj + rowstart[itmp]) = (*aj) * bs + k;
104           *(bv + rowstart[itmp]) = *(av + k * bs + j);
105           rowstart[itmp]++;
106         }
107       }
108       aj++;
109       av += bs2;
110     }
111   }
112   PetscCall(PetscFree2(rowlengths, rowstart));
113   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
114   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
115 
116   if (reuse == MAT_INPLACE_MATRIX) {
117     PetscCall(MatHeaderReplace(A, &B));
118   } else {
119     *newmat = B;
120   }
121   PetscFunctionReturn(PETSC_SUCCESS);
122 }
123 
124 #include <../src/mat/impls/aij/seq/aij.h>
125 
126 PETSC_INTERN PetscErrorCode MatConvert_SeqAIJ_SeqSBAIJ_Preallocate(Mat A, PetscInt **nnz)
127 {
128   Mat_SeqAIJ     *Aa = (Mat_SeqAIJ *)A->data;
129   PetscInt        m, n, bs = PetscAbs(A->rmap->bs);
130   const PetscInt *ai = Aa->i, *aj = Aa->j;
131 
132   PetscFunctionBegin;
133   PetscCall(MatGetSize(A, &m, &n));
134 
135   if (bs == 1) {
136     const PetscInt *adiag = Aa->diag;
137 
138     PetscCall(PetscMalloc1(m, nnz));
139     for (PetscInt i = 0; i < m; i++) {
140       if (adiag[i] == ai[i + 1]) {
141         (*nnz)[i] = 0;
142         for (PetscInt j = ai[i]; j < ai[i + 1]; j++) (*nnz)[i] += (aj[j] > i);
143       } else (*nnz)[i] = ai[i + 1] - adiag[i];
144     }
145   } else {
146     PetscHSetIJ    ht;
147     PetscHashIJKey key;
148     PetscBool      missing;
149 
150     PetscCall(PetscHSetIJCreate(&ht));
151     PetscCall(PetscCalloc1(m / bs, nnz));
152     for (PetscInt i = 0; i < m; i++) {
153       key.i = i / bs;
154       for (PetscInt k = ai[i]; k < ai[i + 1]; k++) {
155         key.j = aj[k] / bs;
156         if (key.j < key.i) continue;
157         PetscCall(PetscHSetIJQueryAdd(ht, key, &missing));
158         if (missing) (*nnz)[key.i]++;
159       }
160     }
161     PetscCall(PetscHSetIJDestroy(&ht));
162   }
163   PetscFunctionReturn(PETSC_SUCCESS);
164 }
165 
166 PETSC_INTERN PetscErrorCode MatConvert_SeqAIJ_SeqSBAIJ(Mat A, MatType newtype, MatReuse reuse, Mat *newmat)
167 {
168   Mat           B;
169   Mat_SeqAIJ   *a = (Mat_SeqAIJ *)A->data;
170   Mat_SeqSBAIJ *b;
171   PetscInt     *ai = a->i, *aj, m = A->rmap->N, n = A->cmap->N, i, j, *bi, *bj, *rowlengths, bs = PetscAbs(A->rmap->bs);
172   MatScalar    *av, *bv;
173   PetscBool     miss = PETSC_FALSE;
174 
175   PetscFunctionBegin;
176 #if !defined(PETSC_USE_COMPLEX)
177   PetscCheck(A->symmetric == PETSC_BOOL3_TRUE, PetscObjectComm((PetscObject)A), PETSC_ERR_USER, "Matrix must be symmetric. Call MatSetOption(mat,MAT_SYMMETRIC,PETSC_TRUE)");
178 #else
179   PetscCheck(A->symmetric == PETSC_BOOL3_TRUE || A->hermitian == PETSC_BOOL3_TRUE, PetscObjectComm((PetscObject)A), PETSC_ERR_USER, "Matrix must be either symmetric or hermitian. Call MatSetOption(mat,MAT_SYMMETRIC,PETSC_TRUE) and/or MatSetOption(mat,MAT_HERMITIAN,PETSC_TRUE)");
180 #endif
181   PetscCheck(n == m, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Matrix must be square");
182 
183   if (bs == 1) {
184     PetscCall(PetscMalloc1(m, &rowlengths));
185     for (i = 0; i < m; i++) {
186       if (a->diag[i] == ai[i + 1]) {             /* missing diagonal */
187         rowlengths[i] = (ai[i + 1] - ai[i]) + 1; /* allocate some extra space */
188         miss          = PETSC_TRUE;
189       } else {
190         rowlengths[i] = (ai[i + 1] - a->diag[i]);
191       }
192     }
193   } else PetscCall(MatConvert_SeqAIJ_SeqSBAIJ_Preallocate(A, &rowlengths));
194   if (reuse != MAT_REUSE_MATRIX) {
195     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
196     PetscCall(MatSetSizes(B, m, n, m, n));
197     PetscCall(MatSetType(B, MATSEQSBAIJ));
198     PetscCall(MatSeqSBAIJSetPreallocation(B, bs, 0, rowlengths));
199   } else B = *newmat;
200 
201   if (bs == 1 && !miss) {
202     b  = (Mat_SeqSBAIJ *)B->data;
203     bi = b->i;
204     bj = b->j;
205     bv = b->a;
206 
207     bi[0] = 0;
208     for (i = 0; i < m; i++) {
209       aj = a->j + a->diag[i];
210       av = a->a + a->diag[i];
211       for (j = 0; j < rowlengths[i]; j++) {
212         *bj = *aj;
213         bj++;
214         aj++;
215         *bv = *av;
216         bv++;
217         av++;
218       }
219       bi[i + 1]  = bi[i] + rowlengths[i];
220       b->ilen[i] = rowlengths[i];
221     }
222     PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
223     PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
224   } else {
225     PetscCall(MatSetOption(B, MAT_IGNORE_LOWER_TRIANGULAR, PETSC_TRUE));
226     /* reuse may not be equal to MAT_REUSE_MATRIX, but the basic converter will reallocate or replace newmat if this value is not used */
227     /* if reuse is equal to MAT_INITIAL_MATRIX, it has been appropriately preallocated before                                          */
228     /*                      MAT_INPLACE_MATRIX, it will be replaced with MatHeaderReplace below                                        */
229     PetscCall(MatConvert_Basic(A, newtype, MAT_REUSE_MATRIX, &B));
230   }
231   PetscCall(PetscFree(rowlengths));
232   if (reuse == MAT_INPLACE_MATRIX) {
233     PetscCall(MatHeaderReplace(A, &B));
234   } else *newmat = B;
235   PetscFunctionReturn(PETSC_SUCCESS);
236 }
237 
238 PETSC_INTERN PetscErrorCode MatConvert_SeqSBAIJ_SeqBAIJ(Mat A, MatType newtype, MatReuse reuse, Mat *newmat)
239 {
240   Mat           B;
241   Mat_SeqSBAIJ *a = (Mat_SeqSBAIJ *)A->data;
242   Mat_SeqBAIJ  *b;
243   PetscInt     *ai = a->i, *aj = a->j, m = A->rmap->N, n = A->cmap->n, i, k, *bi, *bj, *browlengths, nz, *browstart, itmp;
244   PetscInt      bs = A->rmap->bs, bs2 = bs * bs, mbs = m / bs, col, row;
245   MatScalar    *av, *bv;
246 #if defined(PETSC_USE_COMPLEX)
247   const int aconj = A->hermitian == PETSC_BOOL3_TRUE ? 1 : 0;
248 #else
249   const int aconj = 0;
250 #endif
251 
252   PetscFunctionBegin;
253   /* compute browlengths of newmat */
254   PetscCall(PetscMalloc2(mbs, &browlengths, mbs, &browstart));
255   for (i = 0; i < mbs; i++) browlengths[i] = 0;
256   for (i = 0; i < mbs; i++) {
257     nz = ai[i + 1] - ai[i];
258     aj++;                      /* skip diagonal */
259     for (k = 1; k < nz; k++) { /* no. of lower triangular blocks */
260       browlengths[*aj]++;
261       aj++;
262     }
263     browlengths[i] += nz; /* no. of upper triangular blocks */
264   }
265 
266   if (reuse != MAT_REUSE_MATRIX) {
267     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
268     PetscCall(MatSetSizes(B, m, n, m, n));
269     PetscCall(MatSetType(B, MATSEQBAIJ));
270     PetscCall(MatSeqBAIJSetPreallocation(B, bs, 0, browlengths));
271   } else B = *newmat;
272 
273   b  = (Mat_SeqBAIJ *)B->data;
274   bi = b->i;
275   bj = b->j;
276   bv = b->a;
277 
278   /* set b->i */
279   bi[0] = 0;
280   for (i = 0; i < mbs; i++) {
281     b->ilen[i]   = browlengths[i];
282     bi[i + 1]    = bi[i] + browlengths[i];
283     browstart[i] = bi[i];
284   }
285   PetscCheck(bi[mbs] == 2 * a->nz - mbs, PETSC_COMM_SELF, PETSC_ERR_PLIB, "bi[mbs]: %" PetscInt_FMT " != 2*a->nz - mbs: %" PetscInt_FMT, bi[mbs], 2 * a->nz - mbs);
286 
287   /* set b->j and b->a */
288   aj = a->j;
289   av = a->a;
290   for (i = 0; i < mbs; i++) {
291     /* diagonal block */
292     *(bj + browstart[i]) = *aj;
293     aj++;
294 
295     itmp = bs2 * browstart[i];
296     for (k = 0; k < bs2; k++) {
297       *(bv + itmp + k) = *av;
298       av++;
299     }
300     browstart[i]++;
301 
302     nz = ai[i + 1] - ai[i] - 1;
303     while (nz--) {
304       /* lower triangular blocks - transpose blocks of A */
305       *(bj + browstart[*aj]) = i; /* block col index */
306 
307       itmp = bs2 * browstart[*aj]; /* row index */
308       for (col = 0; col < bs; col++) {
309         k = col;
310         for (row = 0; row < bs; row++) {
311           bv[itmp + col * bs + row] = aconj ? PetscConj(av[k]) : av[k];
312           k += bs;
313         }
314       }
315       browstart[*aj]++;
316 
317       /* upper triangular blocks */
318       *(bj + browstart[i]) = *aj;
319       aj++;
320 
321       itmp = bs2 * browstart[i];
322       for (k = 0; k < bs2; k++) bv[itmp + k] = av[k];
323       av += bs2;
324       browstart[i]++;
325     }
326   }
327   PetscCall(PetscFree2(browlengths, browstart));
328   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
329   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
330 
331   if (reuse == MAT_INPLACE_MATRIX) {
332     PetscCall(MatHeaderReplace(A, &B));
333   } else *newmat = B;
334   PetscFunctionReturn(PETSC_SUCCESS);
335 }
336 
337 PETSC_INTERN PetscErrorCode MatConvert_SeqBAIJ_SeqSBAIJ(Mat A, MatType newtype, MatReuse reuse, Mat *newmat)
338 {
339   Mat           B;
340   Mat_SeqBAIJ  *a = (Mat_SeqBAIJ *)A->data;
341   Mat_SeqSBAIJ *b;
342   PetscInt     *ai = a->i, *aj, m = A->rmap->N, n = A->cmap->n, i, j, k, *bi, *bj, *browlengths;
343   PetscInt      bs = A->rmap->bs, bs2 = bs * bs, mbs = m / bs, dd;
344   MatScalar    *av, *bv;
345   PetscBool     flg;
346 
347   PetscFunctionBegin;
348   PetscCheck(A->symmetric, PetscObjectComm((PetscObject)A), PETSC_ERR_USER, "Matrix must be symmetric. Call MatSetOption(mat,MAT_SYMMETRIC,PETSC_TRUE)");
349   PetscCheck(n == m, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Matrix must be square");
350   PetscCall(MatMissingDiagonal_SeqBAIJ(A, &flg, &dd)); /* check for missing diagonals, then mark diag */
351   PetscCheck(!flg, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Matrix is missing diagonal %" PetscInt_FMT, dd);
352 
353   PetscCall(PetscMalloc1(mbs, &browlengths));
354   for (i = 0; i < mbs; i++) browlengths[i] = ai[i + 1] - a->diag[i];
355 
356   if (reuse != MAT_REUSE_MATRIX) {
357     PetscCall(MatCreate(PetscObjectComm((PetscObject)A), &B));
358     PetscCall(MatSetSizes(B, m, n, m, n));
359     PetscCall(MatSetType(B, MATSEQSBAIJ));
360     PetscCall(MatSeqSBAIJSetPreallocation(B, bs, 0, browlengths));
361   } else B = *newmat;
362 
363   b  = (Mat_SeqSBAIJ *)B->data;
364   bi = b->i;
365   bj = b->j;
366   bv = b->a;
367 
368   bi[0] = 0;
369   for (i = 0; i < mbs; i++) {
370     aj = a->j + a->diag[i];
371     av = a->a + (a->diag[i]) * bs2;
372     for (j = 0; j < browlengths[i]; j++) {
373       *bj = *aj;
374       bj++;
375       aj++;
376       for (k = 0; k < bs2; k++) {
377         *bv = *av;
378         bv++;
379         av++;
380       }
381     }
382     bi[i + 1]  = bi[i] + browlengths[i];
383     b->ilen[i] = browlengths[i];
384   }
385   PetscCall(PetscFree(browlengths));
386   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
387   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
388 
389   if (reuse == MAT_INPLACE_MATRIX) {
390     PetscCall(MatHeaderReplace(A, &B));
391   } else *newmat = B;
392   PetscFunctionReturn(PETSC_SUCCESS);
393 }
394