xref: /petsc/src/mat/impls/aij/seq/matrart.c (revision dcca6d9d80ebd869fe6029bd05a3aa9faafef49e)
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   (*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 = MatColoringCreate(*C,&coloring);CHKERRQ(ierr);
70   ierr = MatColoringSetDistance(coloring,2);CHKERRQ(ierr);
71   ierr = MatColoringSetType(coloring,MATCOLORINGSL);CHKERRQ(ierr);
72   ierr = MatColoringSetFromOptions(coloring);CHKERRQ(ierr);
73   ierr = MatColoringApply(coloring,&iscoloring);CHKERRQ(ierr);
74   ierr = MatColoringDestroy(&coloring);CHKERRQ(ierr);
75   ierr = MatTransposeColoringCreate(*C,iscoloring,&matcoloring);CHKERRQ(ierr);
76 
77   rart->matcoloring = matcoloring;
78   ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
79 
80   /* Create Rt_dense */
81   ierr = MatCreate(PETSC_COMM_SELF,&Rt_dense);CHKERRQ(ierr);
82   ierr = MatSetSizes(Rt_dense,A->cmap->n,matcoloring->ncolors,A->cmap->n,matcoloring->ncolors);CHKERRQ(ierr);
83   ierr = MatSetType(Rt_dense,MATSEQDENSE);CHKERRQ(ierr);
84   ierr = MatSeqDenseSetPreallocation(Rt_dense,NULL);CHKERRQ(ierr);
85 
86   Rt_dense->assembled = PETSC_TRUE;
87   rart->Rt            = Rt_dense;
88 
89   /* Create RARt_dense = R*A*Rt_dense */
90   ierr = MatCreate(PETSC_COMM_SELF,&RARt_dense);CHKERRQ(ierr);
91   ierr = MatSetSizes(RARt_dense,(*C)->rmap->n,matcoloring->ncolors,(*C)->rmap->n,matcoloring->ncolors);CHKERRQ(ierr);
92   ierr = MatSetType(RARt_dense,MATSEQDENSE);CHKERRQ(ierr);
93   ierr = MatSeqDenseSetPreallocation(RARt_dense,NULL);CHKERRQ(ierr);
94 
95   rart->RARt = RARt_dense;
96 
97   /* Allocate work array to store columns of A*R^T used in MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense() */
98   ierr = PetscMalloc(A->rmap->n*4*sizeof(PetscScalar),&rart->work);CHKERRQ(ierr);
99 
100   rart->destroy      = (*C)->ops->destroy;
101   (*C)->ops->destroy = MatDestroy_SeqAIJ_RARt;
102 
103   /* clean up */
104   ierr = MatRestoreSymbolicTranspose_SeqAIJ(R,&rti,&rtj);CHKERRQ(ierr);
105   ierr = MatDestroy(&P);CHKERRQ(ierr);
106 
107 #if defined(PETSC_USE_INFO)
108   {
109     PetscReal density= (PetscReal)(c->nz)/(RARt_dense->rmap->n*RARt_dense->cmap->n);
110     ierr = PetscInfo(*C,"C=R*(A*Rt) via coloring C - use sparse-dense inner products\n");CHKERRQ(ierr);
111     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);
112   }
113 #endif
114   PetscFunctionReturn(0);
115 }
116 
117 /*
118  RAB = R * A * B, R and A in seqaij format, B in dense format;
119 */
120 #undef __FUNCT__
121 #define __FUNCT__ "MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense"
122 PetscErrorCode MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(Mat R,Mat A,Mat B,Mat RAB,PetscScalar *work)
123 {
124   Mat_SeqAIJ     *a=(Mat_SeqAIJ*)A->data,*r=(Mat_SeqAIJ*)R->data;
125   PetscErrorCode ierr;
126   PetscScalar    *b,r1,r2,r3,r4,*b1,*b2,*b3,*b4;
127   MatScalar      *aa,*ra;
128   PetscInt       cn =B->cmap->n,bm=B->rmap->n,col,i,j,n,*ai=a->i,*aj,am=A->rmap->n;
129   PetscInt       am2=2*am,am3=3*am,bm4=4*bm;
130   PetscScalar    *d,*c,*c2,*c3,*c4;
131   PetscInt       *rj,rm=R->rmap->n,dm=RAB->rmap->n,dn=RAB->cmap->n;
132   PetscInt       rm2=2*rm,rm3=3*rm,colrm;
133 
134   PetscFunctionBegin;
135   if (!dm || !dn) PetscFunctionReturn(0);
136   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);
137   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);
138   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);
139   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);
140 
141   { /*
142      This approach is not as good as original ones (will be removed later), but it reveals that
143      AB_den=A*B takes almost all execution time in R*A*B for src/ksp/ksp/examples/tutorials/ex56.c
144      */
145     PetscBool via_matmatmult=PETSC_FALSE;
146     ierr = PetscOptionsGetBool(NULL,"-matrart_via_matmatmult",&via_matmatmult,NULL);CHKERRQ(ierr);
147     if (via_matmatmult) {
148       Mat AB_den;
149       ierr = MatMatMultSymbolic_SeqAIJ_SeqDense(A,B,0.0,&AB_den);CHKERRQ(ierr);
150       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(A,B,AB_den);CHKERRQ(ierr);
151       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(R,AB_den,RAB);CHKERRQ(ierr);
152       ierr = MatDestroy(&AB_den);CHKERRQ(ierr);
153       PetscFunctionReturn(0);
154     }
155   }
156 
157   ierr = MatDenseGetArray(B,&b);CHKERRQ(ierr);
158   ierr = MatDenseGetArray(RAB,&d);CHKERRQ(ierr);
159   b1   = b; b2 = b1 + bm; b3 = b2 + bm; b4 = b3 + bm;
160   c    = work; c2 = c + am; c3 = c2 + am; c4 = c3 + am;
161   for (col=0; col<cn-4; col += 4) {  /* over columns of C */
162     for (i=0; i<am; i++) {        /* over rows of A in those columns */
163       r1 = r2 = r3 = r4 = 0.0;
164       n  = ai[i+1] - ai[i];
165       aj = a->j + ai[i];
166       aa = a->a + ai[i];
167       for (j=0; j<n; j++) {
168         r1 += (*aa)*b1[*aj];
169         r2 += (*aa)*b2[*aj];
170         r3 += (*aa)*b3[*aj];
171         r4 += (*aa++)*b4[*aj++];
172       }
173       c[i]       = r1;
174       c[am  + i] = r2;
175       c[am2 + i] = r3;
176       c[am3 + i] = r4;
177     }
178     b1 += bm4;
179     b2 += bm4;
180     b3 += bm4;
181     b4 += bm4;
182 
183     /* RAB[:,col] = R*C[:,col] */
184     colrm = col*rm;
185     for (i=0; i<rm; i++) {        /* over rows of R in those columns */
186       r1 = r2 = r3 = r4 = 0.0;
187       n  = r->i[i+1] - r->i[i];
188       rj = r->j + r->i[i];
189       ra = r->a + r->i[i];
190       for (j=0; j<n; j++) {
191         r1 += (*ra)*c[*rj];
192         r2 += (*ra)*c2[*rj];
193         r3 += (*ra)*c3[*rj];
194         r4 += (*ra++)*c4[*rj++];
195       }
196       d[colrm + i]       = r1;
197       d[colrm + rm + i]  = r2;
198       d[colrm + rm2 + i] = r3;
199       d[colrm + rm3 + i] = r4;
200     }
201   }
202   for (; col<cn; col++) {     /* over extra columns of C */
203     for (i=0; i<am; i++) {  /* over rows of A in those columns */
204       r1 = 0.0;
205       n  = a->i[i+1] - a->i[i];
206       aj = a->j + a->i[i];
207       aa = a->a + a->i[i];
208       for (j=0; j<n; j++) {
209         r1 += (*aa++)*b1[*aj++];
210       }
211       c[i] = r1;
212     }
213     b1 += bm;
214 
215     for (i=0; i<rm; i++) {  /* over rows of R in those columns */
216       r1 = 0.0;
217       n  = r->i[i+1] - r->i[i];
218       rj = r->j + r->i[i];
219       ra = r->a + r->i[i];
220       for (j=0; j<n; j++) {
221         r1 += (*ra++)*c[*rj++];
222       }
223       d[col*rm + i] = r1;
224     }
225   }
226   ierr = PetscLogFlops(cn*2.0*(a->nz + r->nz));CHKERRQ(ierr);
227 
228   ierr = MatDenseRestoreArray(B,&b);CHKERRQ(ierr);
229   ierr = MatDenseRestoreArray(RAB,&d);CHKERRQ(ierr);
230   ierr = MatAssemblyBegin(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
231   ierr = MatAssemblyEnd(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
232   PetscFunctionReturn(0);
233 }
234 
235 #undef __FUNCT__
236 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart"
237 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart(Mat A,Mat R,Mat C)
238 {
239   PetscErrorCode       ierr;
240   Mat_SeqAIJ           *c = (Mat_SeqAIJ*)C->data;
241   Mat_RARt             *rart=c->rart;
242   MatTransposeColoring matcoloring;
243   Mat                  Rt,RARt;
244 
245   PetscFunctionBegin;
246   /* Get dense Rt by Apply MatTransposeColoring to R */
247   matcoloring = rart->matcoloring;
248   Rt          = rart->Rt;
249   ierr  = MatTransColoringApplySpToDen(matcoloring,R,Rt);CHKERRQ(ierr);
250 
251   /* Get dense RARt = R*A*Rt -- dominates! */
252   RARt = rart->RARt;
253   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(R,A,Rt,RARt,rart->work);CHKERRQ(ierr);
254 
255   /* Recover C from C_dense */
256   ierr = MatTransColoringApplyDenToSp(matcoloring,RARt,C);CHKERRQ(ierr);
257   PetscFunctionReturn(0);
258 }
259 
260 #undef __FUNCT__
261 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult"
262 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,PetscReal fill,Mat *C)
263 {
264   PetscErrorCode  ierr;
265   Mat             ARt,RARt;
266   Mat_SeqAIJ     *c;
267   Mat_RARt       *rart;
268 
269   PetscFunctionBegin;
270   /* must use '-mat_no_inode' with '-matmattransmult_color 1' - do not knwo why? */
271   ierr = MatMatTransposeMultSymbolic_SeqAIJ_SeqAIJ(A,R,fill,&ARt);CHKERRQ(ierr);
272   ierr = MatMatMultSymbolic_SeqAIJ_SeqAIJ(R,ARt,fill,&RARt);CHKERRQ(ierr);
273   *C                     = RARt;
274   RARt->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult;
275 
276   ierr = PetscNew(Mat_RARt,&rart);CHKERRQ(ierr);
277   c         = (Mat_SeqAIJ*)(*C)->data;
278   c->rart   = rart;
279   rart->ARt = ARt;
280   rart->destroy      = RARt->ops->destroy;
281   RARt->ops->destroy = MatDestroy_SeqAIJ_RARt;
282 #if defined(PETSC_USE_INFO)
283   ierr = PetscInfo(*C,"Use ARt=A*R^T, C=R*ARt via MatMatTransposeMult(). Coloring can be applied to A*R^T.\n");CHKERRQ(ierr);
284 #endif
285   PetscFunctionReturn(0);
286 }
287 
288 #undef __FUNCT__
289 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult"
290 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,Mat C)
291 {
292   PetscErrorCode  ierr;
293   Mat_SeqAIJ      *c=(Mat_SeqAIJ*)C->data;
294   Mat_RARt        *rart=c->rart;
295   Mat             ARt=rart->ARt;
296 
297   PetscFunctionBegin;
298   ierr = MatMatTransposeMultNumeric_SeqAIJ_SeqAIJ(A,R,ARt);CHKERRQ(ierr); /* dominate! */
299   ierr = MatMatMultNumeric_SeqAIJ_SeqAIJ(R,ARt,C);CHKERRQ(ierr);
300   PetscFunctionReturn(0);
301 }
302 
303 #undef __FUNCT__
304 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ"
305 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ(Mat A,Mat R,PetscReal fill,Mat *C)
306 {
307   PetscErrorCode  ierr;
308   Mat             Rt;
309   Mat_SeqAIJ      *c;
310   Mat_RARt        *rart;
311 
312   PetscFunctionBegin;
313   ierr = MatTranspose_SeqAIJ(R,MAT_INITIAL_MATRIX,&Rt);CHKERRQ(ierr);
314   ierr = MatMatMatMultSymbolic_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,fill,C);CHKERRQ(ierr);
315 
316   ierr = PetscNew(Mat_RARt,&rart);CHKERRQ(ierr);
317   rart->Rt = Rt;
318   c        = (Mat_SeqAIJ*)(*C)->data;
319   c->rart  = rart;
320   rart->destroy          = (*C)->ops->destroy;
321   (*C)->ops->destroy     = MatDestroy_SeqAIJ_RARt;
322   (*C)->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ;
323 #if defined(PETSC_USE_INFO)
324   ierr = PetscInfo(*C,"Use Rt=R^T and C=R*A*Rt via MatMatMatMult() to avoid sparse inner products\n");CHKERRQ(ierr);
325 #endif
326   PetscFunctionReturn(0);
327 }
328 
329 #undef __FUNCT__
330 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ"
331 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ(Mat A,Mat R,Mat C)
332 {
333   PetscErrorCode  ierr;
334   Mat_SeqAIJ      *c = (Mat_SeqAIJ*)C->data;
335   Mat_RARt        *rart = c->rart;
336   Mat             Rt = rart->Rt;
337 
338   PetscFunctionBegin;
339   ierr = MatTranspose_SeqAIJ(R,MAT_REUSE_MATRIX,&Rt);CHKERRQ(ierr);
340   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,C);CHKERRQ(ierr);
341   PetscFunctionReturn(0);
342 }
343 
344 #undef __FUNCT__
345 #define __FUNCT__ "MatRARt_SeqAIJ_SeqAIJ"
346 PetscErrorCode MatRARt_SeqAIJ_SeqAIJ(Mat A,Mat R,MatReuse scall,PetscReal fill,Mat *C)
347 {
348   PetscErrorCode ierr;
349   const char     *algTypes[3] = {"matmatmatmult","matmattransposemult","coloring_rart"};
350   PetscInt       alg=0; /* set default algorithm */
351 
352   PetscFunctionBegin;
353   if (scall == MAT_INITIAL_MATRIX) {
354     ierr = PetscObjectOptionsBegin((PetscObject)A);CHKERRQ(ierr);
355     ierr = PetscOptionsEList("-matrart_via","Algorithmic approach","MatRARt",algTypes,3,algTypes[0],&alg,NULL);CHKERRQ(ierr);
356     ierr = PetscOptionsEnd();CHKERRQ(ierr);
357 
358     ierr = PetscLogEventBegin(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
359     switch (alg) {
360     case 1:
361       /* via matmattransposemult: ARt=A*R^T, C=R*ARt - matrix coloring can be applied to A*R^T */
362       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(A,R,fill,C);CHKERRQ(ierr);
363       break;
364     case 2:
365       /* via coloring_rart: apply coloring C = R*A*R^T                          */
366       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart(A,R,fill,C);CHKERRQ(ierr);
367       break;
368     default:
369       /* via matmatmatmult: Rt=R^T, C=R*A*Rt - avoid inefficient sparse inner products */
370       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ(A,R,fill,C);CHKERRQ(ierr);
371       break;
372     }
373     ierr = PetscLogEventEnd(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
374   }
375 
376   ierr = PetscLogEventBegin(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
377   ierr = (*(*C)->ops->rartnumeric)(A,R,*C);CHKERRQ(ierr);
378   ierr = PetscLogEventEnd(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
379   PetscFunctionReturn(0);
380 }
381