xref: /petsc/src/mat/impls/aij/seq/matrart.c (revision bebe2cf65d55febe21a5af8db2bd2e168caaa2e7)
1 
2 /*
3   Defines projective product routines where A is a SeqAIJ matrix
4           C = R * A * R^T
5 */
6 
7 #include <../src/mat/impls/aij/seq/aij.h>
8 #include <../src/mat/utils/freespace.h>
9 #include <../src/mat/impls/dense/seq/dense.h> /*I "petscmat.h" I*/
10 
11 #undef __FUNCT__
12 #define __FUNCT__ "MatDestroy_SeqAIJ_RARt"
13 PetscErrorCode MatDestroy_SeqAIJ_RARt(Mat A)
14 {
15   PetscErrorCode ierr;
16   Mat_SeqAIJ     *a    = (Mat_SeqAIJ*)A->data;
17   Mat_RARt       *rart = a->rart;
18 
19   PetscFunctionBegin;
20   ierr = MatTransposeColoringDestroy(&rart->matcoloring);CHKERRQ(ierr);
21   ierr = MatDestroy(&rart->Rt);CHKERRQ(ierr);
22   ierr = MatDestroy(&rart->RARt);CHKERRQ(ierr);
23   ierr = MatDestroy(&rart->ARt);CHKERRQ(ierr);
24   ierr = PetscFree(rart->work);CHKERRQ(ierr);
25 
26   A->ops->destroy = rart->destroy;
27   if (A->ops->destroy) {
28     ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
29   }
30   ierr = PetscFree(rart);CHKERRQ(ierr);
31   PetscFunctionReturn(0);
32 }
33 
34 #undef __FUNCT__
35 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart"
36 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart(Mat A,Mat R,PetscReal fill,Mat *C)
37 {
38   PetscErrorCode       ierr;
39   Mat                  P;
40   PetscInt             *rti,*rtj;
41   Mat_RARt             *rart;
42   MatColoring          coloring;
43   MatTransposeColoring matcoloring;
44   ISColoring           iscoloring;
45   Mat                  Rt_dense,RARt_dense;
46   Mat_SeqAIJ           *c;
47 
48   PetscFunctionBegin;
49   /* create symbolic P=Rt */
50   ierr = MatGetSymbolicTranspose_SeqAIJ(R,&rti,&rtj);CHKERRQ(ierr);
51   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,R->cmap->n,R->rmap->n,rti,rtj,NULL,&P);CHKERRQ(ierr);
52 
53   /* get symbolic C=Pt*A*P */
54   ierr = MatPtAPSymbolic_SeqAIJ_SeqAIJ_SparseAxpy(A,P,fill,C);CHKERRQ(ierr);
55   ierr = MatSetBlockSizes(*C,PetscAbs(R->rmap->bs),PetscAbs(R->rmap->bs));CHKERRQ(ierr);
56   (*C)->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart;
57 
58   /* create a supporting struct */
59   ierr    = PetscNew(&rart);CHKERRQ(ierr);
60   c       = (Mat_SeqAIJ*)(*C)->data;
61   c->rart = rart;
62 
63   /* ------ Use coloring ---------- */
64   /* inode causes memory problem, don't know why */
65   if (c->inode.use) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"MAT_USE_INODES is not supported. Use '-mat_no_inode'");
66 
67   /* Create MatTransposeColoring from symbolic C=R*A*R^T */
68   ierr = MatColoringCreate(*C,&coloring);CHKERRQ(ierr);
69   ierr = MatColoringSetDistance(coloring,2);CHKERRQ(ierr);
70   ierr = MatColoringSetType(coloring,MATCOLORINGSL);CHKERRQ(ierr);
71   ierr = MatColoringSetFromOptions(coloring);CHKERRQ(ierr);
72   ierr = MatColoringApply(coloring,&iscoloring);CHKERRQ(ierr);
73   ierr = MatColoringDestroy(&coloring);CHKERRQ(ierr);
74   ierr = MatTransposeColoringCreate(*C,iscoloring,&matcoloring);CHKERRQ(ierr);
75 
76   rart->matcoloring = matcoloring;
77   ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
78 
79   /* Create Rt_dense */
80   ierr = MatCreate(PETSC_COMM_SELF,&Rt_dense);CHKERRQ(ierr);
81   ierr = MatSetSizes(Rt_dense,A->cmap->n,matcoloring->ncolors,A->cmap->n,matcoloring->ncolors);CHKERRQ(ierr);
82   ierr = MatSetType(Rt_dense,MATSEQDENSE);CHKERRQ(ierr);
83   ierr = MatSeqDenseSetPreallocation(Rt_dense,NULL);CHKERRQ(ierr);
84 
85   Rt_dense->assembled = PETSC_TRUE;
86   rart->Rt            = Rt_dense;
87 
88   /* Create RARt_dense = R*A*Rt_dense */
89   ierr = MatCreate(PETSC_COMM_SELF,&RARt_dense);CHKERRQ(ierr);
90   ierr = MatSetSizes(RARt_dense,(*C)->rmap->n,matcoloring->ncolors,(*C)->rmap->n,matcoloring->ncolors);CHKERRQ(ierr);
91   ierr = MatSetType(RARt_dense,MATSEQDENSE);CHKERRQ(ierr);
92   ierr = MatSeqDenseSetPreallocation(RARt_dense,NULL);CHKERRQ(ierr);
93 
94   rart->RARt = RARt_dense;
95 
96   /* Allocate work array to store columns of A*R^T used in MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense() */
97   ierr = PetscMalloc1(A->rmap->n*4,&rart->work);CHKERRQ(ierr);
98 
99   rart->destroy      = (*C)->ops->destroy;
100   (*C)->ops->destroy = MatDestroy_SeqAIJ_RARt;
101 
102   /* clean up */
103   ierr = MatRestoreSymbolicTranspose_SeqAIJ(R,&rti,&rtj);CHKERRQ(ierr);
104   ierr = MatDestroy(&P);CHKERRQ(ierr);
105 
106 #if defined(PETSC_USE_INFO)
107   {
108     PetscReal density= (PetscReal)(c->nz)/(RARt_dense->rmap->n*RARt_dense->cmap->n);
109     ierr = PetscInfo(*C,"C=R*(A*Rt) via coloring C - use sparse-dense inner products\n");CHKERRQ(ierr);
110     ierr = PetscInfo6(*C,"RARt_den %D %D; Rt %D %D (RARt->nz %D)/(m*ncolors)=%g\n",RARt_dense->rmap->n,RARt_dense->cmap->n,R->cmap->n,R->rmap->n,c->nz,density);CHKERRQ(ierr);
111   }
112 #endif
113   PetscFunctionReturn(0);
114 }
115 
116 /*
117  RAB = R * A * B, R and A in seqaij format, B in dense format;
118 */
119 #undef __FUNCT__
120 #define __FUNCT__ "MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense"
121 PetscErrorCode MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(Mat R,Mat A,Mat B,Mat RAB,PetscScalar *work)
122 {
123   Mat_SeqAIJ     *a=(Mat_SeqAIJ*)A->data,*r=(Mat_SeqAIJ*)R->data;
124   PetscErrorCode ierr;
125   PetscScalar    *b,r1,r2,r3,r4,*b1,*b2,*b3,*b4;
126   MatScalar      *aa,*ra;
127   PetscInt       cn =B->cmap->n,bm=B->rmap->n,col,i,j,n,*ai=a->i,*aj,am=A->rmap->n;
128   PetscInt       am2=2*am,am3=3*am,bm4=4*bm;
129   PetscScalar    *d,*c,*c2,*c3,*c4;
130   PetscInt       *rj,rm=R->rmap->n,dm=RAB->rmap->n,dn=RAB->cmap->n;
131   PetscInt       rm2=2*rm,rm3=3*rm,colrm;
132 
133   PetscFunctionBegin;
134   if (!dm || !dn) PetscFunctionReturn(0);
135   if (bm != A->cmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Number columns in A %D not equal rows in B %D\n",A->cmap->n,bm);
136   if (am != R->cmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Number columns in R %D not equal rows in A %D\n",R->cmap->n,am);
137   if (R->rmap->n != RAB->rmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Number rows in RAB %D not equal rows in R %D\n",RAB->rmap->n,R->rmap->n);
138   if (B->cmap->n != RAB->cmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Number columns in RAB %D not equal columns in B %D\n",RAB->cmap->n,B->cmap->n);
139 
140   { /*
141      This approach is not as good as original ones (will be removed later), but it reveals that
142      AB_den=A*B takes almost all execution time in R*A*B for src/ksp/ksp/examples/tutorials/ex56.c
143      */
144     PetscBool via_matmatmult=PETSC_FALSE;
145     ierr = PetscOptionsGetBool(NULL,"-matrart_via_matmatmult",&via_matmatmult,NULL);CHKERRQ(ierr);
146     if (via_matmatmult) {
147       Mat AB_den;
148       ierr = MatMatMultSymbolic_SeqAIJ_SeqDense(A,B,0.0,&AB_den);CHKERRQ(ierr);
149       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(A,B,AB_den);CHKERRQ(ierr);
150       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(R,AB_den,RAB);CHKERRQ(ierr);
151       ierr = MatDestroy(&AB_den);CHKERRQ(ierr);
152       PetscFunctionReturn(0);
153     }
154   }
155 
156   ierr = MatDenseGetArray(B,&b);CHKERRQ(ierr);
157   ierr = MatDenseGetArray(RAB,&d);CHKERRQ(ierr);
158   b1   = b; b2 = b1 + bm; b3 = b2 + bm; b4 = b3 + bm;
159   c    = work; c2 = c + am; c3 = c2 + am; c4 = c3 + am;
160   for (col=0; col<cn-4; col += 4) {  /* over columns of C */
161     for (i=0; i<am; i++) {        /* over rows of A in those columns */
162       r1 = r2 = r3 = r4 = 0.0;
163       n  = ai[i+1] - ai[i];
164       aj = a->j + ai[i];
165       aa = a->a + ai[i];
166       for (j=0; j<n; j++) {
167         r1 += (*aa)*b1[*aj];
168         r2 += (*aa)*b2[*aj];
169         r3 += (*aa)*b3[*aj];
170         r4 += (*aa++)*b4[*aj++];
171       }
172       c[i]       = r1;
173       c[am  + i] = r2;
174       c[am2 + i] = r3;
175       c[am3 + i] = r4;
176     }
177     b1 += bm4;
178     b2 += bm4;
179     b3 += bm4;
180     b4 += bm4;
181 
182     /* RAB[:,col] = R*C[:,col] */
183     colrm = col*rm;
184     for (i=0; i<rm; i++) {        /* over rows of R in those columns */
185       r1 = r2 = r3 = r4 = 0.0;
186       n  = r->i[i+1] - r->i[i];
187       rj = r->j + r->i[i];
188       ra = r->a + r->i[i];
189       for (j=0; j<n; j++) {
190         r1 += (*ra)*c[*rj];
191         r2 += (*ra)*c2[*rj];
192         r3 += (*ra)*c3[*rj];
193         r4 += (*ra++)*c4[*rj++];
194       }
195       d[colrm + i]       = r1;
196       d[colrm + rm + i]  = r2;
197       d[colrm + rm2 + i] = r3;
198       d[colrm + rm3 + i] = r4;
199     }
200   }
201   for (; col<cn; col++) {     /* over extra columns of C */
202     for (i=0; i<am; i++) {  /* over rows of A in those columns */
203       r1 = 0.0;
204       n  = a->i[i+1] - a->i[i];
205       aj = a->j + a->i[i];
206       aa = a->a + a->i[i];
207       for (j=0; j<n; j++) {
208         r1 += (*aa++)*b1[*aj++];
209       }
210       c[i] = r1;
211     }
212     b1 += bm;
213 
214     for (i=0; i<rm; i++) {  /* over rows of R in those columns */
215       r1 = 0.0;
216       n  = r->i[i+1] - r->i[i];
217       rj = r->j + r->i[i];
218       ra = r->a + r->i[i];
219       for (j=0; j<n; j++) {
220         r1 += (*ra++)*c[*rj++];
221       }
222       d[col*rm + i] = r1;
223     }
224   }
225   ierr = PetscLogFlops(cn*2.0*(a->nz + r->nz));CHKERRQ(ierr);
226 
227   ierr = MatDenseRestoreArray(B,&b);CHKERRQ(ierr);
228   ierr = MatDenseRestoreArray(RAB,&d);CHKERRQ(ierr);
229   ierr = MatAssemblyBegin(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
230   ierr = MatAssemblyEnd(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
231   PetscFunctionReturn(0);
232 }
233 
234 #undef __FUNCT__
235 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart"
236 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart(Mat A,Mat R,Mat C)
237 {
238   PetscErrorCode       ierr;
239   Mat_SeqAIJ           *c = (Mat_SeqAIJ*)C->data;
240   Mat_RARt             *rart=c->rart;
241   MatTransposeColoring matcoloring;
242   Mat                  Rt,RARt;
243 
244   PetscFunctionBegin;
245   /* Get dense Rt by Apply MatTransposeColoring to R */
246   matcoloring = rart->matcoloring;
247   Rt          = rart->Rt;
248   ierr  = MatTransColoringApplySpToDen(matcoloring,R,Rt);CHKERRQ(ierr);
249 
250   /* Get dense RARt = R*A*Rt -- dominates! */
251   RARt = rart->RARt;
252   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(R,A,Rt,RARt,rart->work);CHKERRQ(ierr);
253 
254   /* Recover C from C_dense */
255   ierr = MatTransColoringApplyDenToSp(matcoloring,RARt,C);CHKERRQ(ierr);
256   PetscFunctionReturn(0);
257 }
258 
259 #undef __FUNCT__
260 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult"
261 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,PetscReal fill,Mat *C)
262 {
263   PetscErrorCode  ierr;
264   Mat             ARt,RARt;
265   Mat_SeqAIJ     *c;
266   Mat_RARt       *rart;
267 
268   PetscFunctionBegin;
269   /* must use '-mat_no_inode' with '-matmattransmult_color 1' - do not knwo why? */
270   ierr = MatMatTransposeMultSymbolic_SeqAIJ_SeqAIJ(A,R,fill,&ARt);CHKERRQ(ierr);
271   ierr = MatMatMultSymbolic_SeqAIJ_SeqAIJ(R,ARt,fill,&RARt);CHKERRQ(ierr);
272   *C                     = RARt;
273   RARt->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult;
274 
275   ierr = PetscNew(&rart);CHKERRQ(ierr);
276   c         = (Mat_SeqAIJ*)(*C)->data;
277   c->rart   = rart;
278   rart->ARt = ARt;
279   rart->destroy      = RARt->ops->destroy;
280   RARt->ops->destroy = MatDestroy_SeqAIJ_RARt;
281 #if defined(PETSC_USE_INFO)
282   ierr = PetscInfo(*C,"Use ARt=A*R^T, C=R*ARt via MatMatTransposeMult(). Coloring can be applied to A*R^T.\n");CHKERRQ(ierr);
283 #endif
284   PetscFunctionReturn(0);
285 }
286 
287 #undef __FUNCT__
288 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult"
289 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,Mat C)
290 {
291   PetscErrorCode  ierr;
292   Mat_SeqAIJ      *c=(Mat_SeqAIJ*)C->data;
293   Mat_RARt        *rart=c->rart;
294   Mat             ARt=rart->ARt;
295 
296   PetscFunctionBegin;
297   ierr = MatMatTransposeMultNumeric_SeqAIJ_SeqAIJ(A,R,ARt);CHKERRQ(ierr); /* dominate! */
298   ierr = MatMatMultNumeric_SeqAIJ_SeqAIJ(R,ARt,C);CHKERRQ(ierr);
299   PetscFunctionReturn(0);
300 }
301 
302 #undef __FUNCT__
303 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ"
304 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ(Mat A,Mat R,PetscReal fill,Mat *C)
305 {
306   PetscErrorCode  ierr;
307   Mat             Rt;
308   Mat_SeqAIJ      *c;
309   Mat_RARt        *rart;
310 
311   PetscFunctionBegin;
312   ierr = MatTranspose_SeqAIJ(R,MAT_INITIAL_MATRIX,&Rt);CHKERRQ(ierr);
313   ierr = MatMatMatMultSymbolic_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,fill,C);CHKERRQ(ierr);
314 
315   ierr = PetscNew(&rart);CHKERRQ(ierr);
316   rart->Rt = Rt;
317   c        = (Mat_SeqAIJ*)(*C)->data;
318   c->rart  = rart;
319   rart->destroy          = (*C)->ops->destroy;
320   (*C)->ops->destroy     = MatDestroy_SeqAIJ_RARt;
321   (*C)->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ;
322 #if defined(PETSC_USE_INFO)
323   ierr = PetscInfo(*C,"Use Rt=R^T and C=R*A*Rt via MatMatMatMult() to avoid sparse inner products\n");CHKERRQ(ierr);
324 #endif
325   PetscFunctionReturn(0);
326 }
327 
328 #undef __FUNCT__
329 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ"
330 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ(Mat A,Mat R,Mat C)
331 {
332   PetscErrorCode  ierr;
333   Mat_SeqAIJ      *c = (Mat_SeqAIJ*)C->data;
334   Mat_RARt        *rart = c->rart;
335   Mat             Rt = rart->Rt;
336 
337   PetscFunctionBegin;
338   ierr = MatTranspose_SeqAIJ(R,MAT_REUSE_MATRIX,&Rt);CHKERRQ(ierr);
339   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,C);CHKERRQ(ierr);
340   PetscFunctionReturn(0);
341 }
342 
343 #undef __FUNCT__
344 #define __FUNCT__ "MatRARt_SeqAIJ_SeqAIJ"
345 PetscErrorCode MatRARt_SeqAIJ_SeqAIJ(Mat A,Mat R,MatReuse scall,PetscReal fill,Mat *C)
346 {
347   PetscErrorCode ierr;
348   const char     *algTypes[3] = {"matmatmatmult","matmattransposemult","coloring_rart"};
349   PetscInt       alg=0; /* set default algorithm */
350 
351   PetscFunctionBegin;
352   if (scall == MAT_INITIAL_MATRIX) {
353     ierr = PetscObjectOptionsBegin((PetscObject)A);CHKERRQ(ierr);
354     ierr = PetscOptionsEList("-matrart_via","Algorithmic approach","MatRARt",algTypes,3,algTypes[0],&alg,NULL);CHKERRQ(ierr);
355     ierr = PetscOptionsEnd();CHKERRQ(ierr);
356 
357     ierr = PetscLogEventBegin(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
358     switch (alg) {
359     case 1:
360       /* via matmattransposemult: ARt=A*R^T, C=R*ARt - matrix coloring can be applied to A*R^T */
361       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(A,R,fill,C);CHKERRQ(ierr);
362       break;
363     case 2:
364       /* via coloring_rart: apply coloring C = R*A*R^T                          */
365       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart(A,R,fill,C);CHKERRQ(ierr);
366       break;
367     default:
368       /* via matmatmatmult: Rt=R^T, C=R*A*Rt - avoid inefficient sparse inner products */
369       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ(A,R,fill,C);CHKERRQ(ierr);
370       break;
371     }
372     ierr = PetscLogEventEnd(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
373   }
374 
375   ierr = PetscLogEventBegin(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
376   ierr = (*(*C)->ops->rartnumeric)(A,R,*C);CHKERRQ(ierr);
377   ierr = PetscLogEventEnd(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
378   PetscFunctionReturn(0);
379 }
380