xref: /petsc/src/mat/impls/aij/seq/matrart.c (revision aed5ffcbc31e41b96407a92d0c19d6464f10f960)
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 #include <petsctime.h>
11 
12 #undef __FUNCT__
13 #define __FUNCT__ "MatDestroy_SeqAIJ_RARt"
14 PetscErrorCode MatDestroy_SeqAIJ_RARt(Mat A)
15 {
16   PetscErrorCode ierr;
17   Mat_SeqAIJ     *a    = (Mat_SeqAIJ*)A->data;
18   Mat_RARt       *rart = a->rart;
19 
20   PetscFunctionBegin;
21   ierr = MatTransposeColoringDestroy(&rart->matcoloring);CHKERRQ(ierr);
22   ierr = MatDestroy(&rart->Rt);CHKERRQ(ierr);
23   ierr = MatDestroy(&rart->RARt);CHKERRQ(ierr);
24   ierr = MatDestroy(&rart->ARt);CHKERRQ(ierr);
25   ierr = PetscFree(rart->work);CHKERRQ(ierr);
26 
27   A->ops->destroy = rart->destroy;
28   if (A->ops->destroy) {
29     ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
30   }
31   ierr = PetscFree(rart);CHKERRQ(ierr);
32   PetscFunctionReturn(0);
33 }
34 
35 #undef __FUNCT__
36 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart"
37 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart(Mat A,Mat R,PetscReal fill,Mat *C)
38 {
39   PetscErrorCode       ierr;
40   Mat                  P;
41   PetscInt             *rti,*rtj;
42   Mat_RARt             *rart;
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   (*C)->rmap->bs = R->rmap->bs;
56   (*C)->cmap->bs = R->rmap->bs;
57   (*C)->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart;
58 
59   /* create a supporting struct */
60   ierr    = PetscNew(Mat_RARt,&rart);CHKERRQ(ierr);
61   c       = (Mat_SeqAIJ*)(*C)->data;
62   c->rart = rart;
63 
64   /* ------ Use coloring ---------- */
65   /* inode causes memory problem, don't know why */
66   if (c->inode.use) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"MAT_USE_INODES is not supported. Use '-mat_no_inode'");
67 
68   /* Create MatTransposeColoring from symbolic C=R*A*R^T */
69   ierr = MatGetColoring(*C,MATCOLORINGLF,&iscoloring);CHKERRQ(ierr);
70   ierr = MatTransposeColoringCreate(*C,iscoloring,&matcoloring);CHKERRQ(ierr);
71 
72   rart->matcoloring = matcoloring;
73   ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
74 
75   /* Create Rt_dense */
76   ierr = MatCreate(PETSC_COMM_SELF,&Rt_dense);CHKERRQ(ierr);
77   ierr = MatSetSizes(Rt_dense,A->cmap->n,matcoloring->ncolors,A->cmap->n,matcoloring->ncolors);CHKERRQ(ierr);
78   ierr = MatSetType(Rt_dense,MATSEQDENSE);CHKERRQ(ierr);
79   ierr = MatSeqDenseSetPreallocation(Rt_dense,NULL);CHKERRQ(ierr);
80 
81   Rt_dense->assembled = PETSC_TRUE;
82   rart->Rt            = Rt_dense;
83 
84   /* Create RARt_dense = R*A*Rt_dense */
85   ierr = MatCreate(PETSC_COMM_SELF,&RARt_dense);CHKERRQ(ierr);
86   ierr = MatSetSizes(RARt_dense,(*C)->rmap->n,matcoloring->ncolors,(*C)->rmap->n,matcoloring->ncolors);CHKERRQ(ierr);
87   ierr = MatSetType(RARt_dense,MATSEQDENSE);CHKERRQ(ierr);
88   ierr = MatSeqDenseSetPreallocation(RARt_dense,NULL);CHKERRQ(ierr);
89 
90   rart->RARt = RARt_dense;
91 
92   /* Allocate work array to store columns of A*R^T used in MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense() */
93   ierr = PetscMalloc(A->rmap->n*4*sizeof(PetscScalar),&rart->work);CHKERRQ(ierr);
94 
95   rart->destroy      = (*C)->ops->destroy;
96   (*C)->ops->destroy = MatDestroy_SeqAIJ_RARt;
97 
98   /* clean up */
99   ierr = MatRestoreSymbolicTranspose_SeqAIJ(R,&rti,&rtj);CHKERRQ(ierr);
100   ierr = MatDestroy(&P);CHKERRQ(ierr);
101 
102 #if defined(PETSC_USE_INFO)
103   {
104     PetscReal density= (PetscReal)(c->nz)/(RARt_dense->rmap->n*RARt_dense->cmap->n);
105     ierr = PetscInfo(*C,"C=R*(A*Rt) via coloring C - use sparse-dense inner products\n");CHKERRQ(ierr);
106     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);
107   }
108 #endif
109   PetscFunctionReturn(0);
110 }
111 
112 /*
113  RAB = R * A * B, R and A in seqaij format, B in dense format;
114 */
115 #undef __FUNCT__
116 #define __FUNCT__ "MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense"
117 PetscErrorCode MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(Mat R,Mat A,Mat B,Mat RAB,PetscScalar *work)
118 {
119   Mat_SeqAIJ     *a=(Mat_SeqAIJ*)A->data,*r=(Mat_SeqAIJ*)R->data;
120   PetscErrorCode ierr;
121   PetscScalar    *b,r1,r2,r3,r4,*b1,*b2,*b3,*b4;
122   MatScalar      *aa,*ra;
123   PetscInt       cn =B->cmap->n,bm=B->rmap->n,col,i,j,n,*ai=a->i,*aj,am=A->rmap->n;
124   PetscInt       am2=2*am,am3=3*am,bm4=4*bm;
125   PetscScalar    *d,*c,*c2,*c3,*c4;
126   PetscInt       *rj,rm=R->rmap->n,dm=RAB->rmap->n,dn=RAB->cmap->n;
127   PetscInt       rm2=2*rm,rm3=3*rm,colrm;
128 
129   PetscFunctionBegin;
130   if (!dm || !dn) PetscFunctionReturn(0);
131   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);
132   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);
133   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);
134   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);
135 
136   { /*
137      This approach is not as good as original ones (will be removed later), but it reveals that
138      AB_den=A*B takes almost all execution time in R*A*B for src/ksp/ksp/examples/tutorials/ex56.c
139      */
140     PetscBool via_matmatmult=PETSC_FALSE;
141     ierr = PetscOptionsGetBool(NULL,"-matrart_via_matmatmult",&via_matmatmult,NULL);CHKERRQ(ierr);
142     if (via_matmatmult) {
143       Mat AB_den;
144       ierr = MatMatMultSymbolic_SeqAIJ_SeqDense(A,B,0.0,&AB_den);CHKERRQ(ierr);
145       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(A,B,AB_den);CHKERRQ(ierr);
146       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(R,AB_den,RAB);CHKERRQ(ierr);
147       ierr = MatDestroy(&AB_den);CHKERRQ(ierr);
148       PetscFunctionReturn(0);
149     }
150   }
151 
152   ierr = MatDenseGetArray(B,&b);CHKERRQ(ierr);
153   ierr = MatDenseGetArray(RAB,&d);CHKERRQ(ierr);
154   b1   = b; b2 = b1 + bm; b3 = b2 + bm; b4 = b3 + bm;
155   c    = work; c2 = c + am; c3 = c2 + am; c4 = c3 + am;
156   for (col=0; col<cn-4; col += 4) {  /* over columns of C */
157     for (i=0; i<am; i++) {        /* over rows of A in those columns */
158       r1 = r2 = r3 = r4 = 0.0;
159       n  = ai[i+1] - ai[i];
160       aj = a->j + ai[i];
161       aa = a->a + ai[i];
162       for (j=0; j<n; j++) {
163         r1 += (*aa)*b1[*aj];
164         r2 += (*aa)*b2[*aj];
165         r3 += (*aa)*b3[*aj];
166         r4 += (*aa++)*b4[*aj++];
167       }
168       c[i]       = r1;
169       c[am  + i] = r2;
170       c[am2 + i] = r3;
171       c[am3 + i] = r4;
172     }
173     b1 += bm4;
174     b2 += bm4;
175     b3 += bm4;
176     b4 += bm4;
177 
178     /* RAB[:,col] = R*C[:,col] */
179     colrm = col*rm;
180     for (i=0; i<rm; i++) {        /* over rows of R in those columns */
181       r1 = r2 = r3 = r4 = 0.0;
182       n  = r->i[i+1] - r->i[i];
183       rj = r->j + r->i[i];
184       ra = r->a + r->i[i];
185       for (j=0; j<n; j++) {
186         r1 += (*ra)*c[*rj];
187         r2 += (*ra)*c2[*rj];
188         r3 += (*ra)*c3[*rj];
189         r4 += (*ra++)*c4[*rj++];
190       }
191       d[colrm + i]       = r1;
192       d[colrm + rm + i]  = r2;
193       d[colrm + rm2 + i] = r3;
194       d[colrm + rm3 + i] = r4;
195     }
196   }
197   for (; col<cn; col++) {     /* over extra columns of C */
198     for (i=0; i<am; i++) {  /* over rows of A in those columns */
199       r1 = 0.0;
200       n  = a->i[i+1] - a->i[i];
201       aj = a->j + a->i[i];
202       aa = a->a + a->i[i];
203       for (j=0; j<n; j++) {
204         r1 += (*aa++)*b1[*aj++];
205       }
206       c[i] = r1;
207     }
208     b1 += bm;
209 
210     for (i=0; i<rm; i++) {  /* over rows of R in those columns */
211       r1 = 0.0;
212       n  = r->i[i+1] - r->i[i];
213       rj = r->j + r->i[i];
214       ra = r->a + r->i[i];
215       for (j=0; j<n; j++) {
216         r1 += (*ra++)*c[*rj++];
217       }
218       d[col*rm + i] = r1;
219     }
220   }
221   ierr = PetscLogFlops(cn*2.0*(a->nz + r->nz));CHKERRQ(ierr);
222 
223   ierr = MatDenseRestoreArray(B,&b);CHKERRQ(ierr);
224   ierr = MatDenseRestoreArray(RAB,&d);CHKERRQ(ierr);
225   ierr = MatAssemblyBegin(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
226   ierr = MatAssemblyEnd(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
227   PetscFunctionReturn(0);
228 }
229 
230 #undef __FUNCT__
231 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart"
232 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart(Mat A,Mat R,Mat C)
233 {
234   PetscErrorCode       ierr;
235   Mat_SeqAIJ           *c = (Mat_SeqAIJ*)C->data;
236   Mat_RARt             *rart=c->rart;
237   MatTransposeColoring matcoloring;
238   Mat                  Rt,RARt;
239 
240   PetscFunctionBegin;
241   /* Get dense Rt by Apply MatTransposeColoring to R */
242   matcoloring = rart->matcoloring;
243   Rt          = rart->Rt;
244   ierr  = MatTransColoringApplySpToDen(matcoloring,R,Rt);CHKERRQ(ierr);
245 
246   /* Get dense RARt = R*A*Rt -- dominates! */
247   RARt = rart->RARt;
248   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(R,A,Rt,RARt,rart->work);CHKERRQ(ierr);
249 
250   /* Recover C from C_dense */
251   ierr = MatTransColoringApplyDenToSp(matcoloring,RARt,C);CHKERRQ(ierr);
252   PetscFunctionReturn(0);
253 }
254 
255 #undef __FUNCT__
256 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult"
257 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,PetscReal fill,Mat *C)
258 {
259   PetscErrorCode  ierr;
260   Mat             ARt,RARt;
261   Mat_SeqAIJ     *c;
262   Mat_RARt       *rart;
263 
264   PetscFunctionBegin;
265   /* must use '-mat_no_inode' with '-matmattransmult_color 1' - do not knwo why? */
266   ierr = MatMatTransposeMultSymbolic_SeqAIJ_SeqAIJ(A,R,fill,&ARt);CHKERRQ(ierr);
267   ierr = MatMatMultSymbolic_SeqAIJ_SeqAIJ(R,ARt,fill,&RARt);CHKERRQ(ierr);
268   *C                     = RARt;
269   RARt->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult;
270 
271   ierr = PetscNew(Mat_RARt,&rart);CHKERRQ(ierr);
272   c         = (Mat_SeqAIJ*)(*C)->data;
273   c->rart   = rart;
274   rart->ARt = ARt;
275   rart->destroy      = RARt->ops->destroy;
276   RARt->ops->destroy = MatDestroy_SeqAIJ_RARt;
277 #if defined(PETSC_USE_INFO)
278   ierr = PetscInfo(*C,"Use ARt=A*R^T, C=R*ARt via MatMatTransposeMult(). Coloring can be applied to A*R^T.\n");CHKERRQ(ierr);
279 #endif
280   PetscFunctionReturn(0);
281 }
282 
283 #undef __FUNCT__
284 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult"
285 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,Mat C)
286 {
287   PetscErrorCode  ierr;
288   Mat_SeqAIJ      *c=(Mat_SeqAIJ*)C->data;
289   Mat_RARt        *rart=c->rart;
290   Mat             ARt=rart->ARt;
291 
292   PetscFunctionBegin;
293   ierr = MatMatTransposeMultNumeric_SeqAIJ_SeqAIJ(A,R,ARt);CHKERRQ(ierr); /* dominate! */
294   ierr = MatMatMultNumeric_SeqAIJ_SeqAIJ(R,ARt,C);CHKERRQ(ierr);
295   PetscFunctionReturn(0);
296 }
297 
298 #undef __FUNCT__
299 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ"
300 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ(Mat A,Mat R,PetscReal fill,Mat *C)
301 {
302   PetscErrorCode  ierr;
303   Mat             Rt;
304   Mat_SeqAIJ      *c;
305   Mat_RARt        *rart;
306 
307   PetscFunctionBegin;
308   ierr = MatTranspose_SeqAIJ(R,MAT_INITIAL_MATRIX,&Rt);CHKERRQ(ierr);
309   ierr = MatMatMatMultSymbolic_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,fill,C);CHKERRQ(ierr);
310 
311   ierr = PetscNew(Mat_RARt,&rart);CHKERRQ(ierr);
312   rart->Rt = Rt;
313   c        = (Mat_SeqAIJ*)(*C)->data;
314   c->rart  = rart;
315   rart->destroy          = (*C)->ops->destroy;
316   (*C)->ops->destroy     = MatDestroy_SeqAIJ_RARt;
317   (*C)->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ;
318 #if defined(PETSC_USE_INFO)
319   ierr = PetscInfo(*C,"Use Rt=R^T and C=R*A*Rt via MatMatMatMult() to avoid sparse inner products\n");CHKERRQ(ierr);
320 #endif
321   PetscFunctionReturn(0);
322 }
323 
324 #undef __FUNCT__
325 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ"
326 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ(Mat A,Mat R,Mat C)
327 {
328   PetscErrorCode  ierr;
329   Mat_SeqAIJ      *c = (Mat_SeqAIJ*)C->data;
330   Mat_RARt        *rart = c->rart;
331   Mat             Rt = rart->Rt;
332 
333   PetscFunctionBegin;
334   ierr = MatTranspose_SeqAIJ(R,MAT_REUSE_MATRIX,&Rt);CHKERRQ(ierr);
335   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,C);CHKERRQ(ierr);
336   PetscFunctionReturn(0);
337 }
338 
339 #undef __FUNCT__
340 #define __FUNCT__ "MatRARt_SeqAIJ_SeqAIJ"
341 PetscErrorCode MatRARt_SeqAIJ_SeqAIJ(Mat A,Mat R,MatReuse scall,PetscReal fill,Mat *C)
342 {
343   PetscErrorCode ierr;
344   const char     *algTypes[3] = {"matmatmatmult","matmattransposemult","coloring_rart"};
345   PetscInt       alg=0; /* set default algorithm */
346 
347   PetscFunctionBegin;
348   if (scall == MAT_INITIAL_MATRIX) {
349     ierr = PetscObjectOptionsBegin((PetscObject)A);CHKERRQ(ierr);
350     ierr = PetscOptionsEList("-matrart_via","Algorithmic approach","MatRARt",algTypes,3,algTypes[0],&alg,NULL);CHKERRQ(ierr);
351     ierr = PetscOptionsEnd();CHKERRQ(ierr);
352 
353     ierr = PetscLogEventBegin(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
354     switch (alg) {
355     case 1:
356       /* via matmattransposemult: ARt=A*R^T, C=R*ARt - matrix coloring can be applied to A*R^T */
357       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(A,R,fill,C);CHKERRQ(ierr);
358       break;
359     case 2:
360       /* via coloring_rart: apply coloring C = R*A*R^T                          */
361       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart(A,R,fill,C);CHKERRQ(ierr);
362       break;
363     default:
364       /* via matmatmatmult: Rt=R^T, C=R*A*Rt - avoid inefficient sparse inner products */
365       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ(A,R,fill,C);CHKERRQ(ierr);
366       break;
367     }
368     ierr = PetscLogEventEnd(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
369   }
370 
371   ierr = PetscLogEventBegin(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
372   ierr = (*(*C)->ops->rartnumeric)(A,R,*C);CHKERRQ(ierr);
373   ierr = PetscLogEventEnd(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
374   PetscFunctionReturn(0);
375 }
376