xref: /petsc/src/mat/impls/aij/seq/matrart.c (revision cd4f06795c1a07b2ececbe72e79aa38424e61c2b)
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   MatColoring          coloring;
44   MatTransposeColoring matcoloring;
45   ISColoring           iscoloring;
46   Mat                  Rt_dense,RARt_dense;
47   Mat_SeqAIJ           *c;
48 
49   PetscFunctionBegin;
50   /* create symbolic P=Rt */
51   ierr = MatGetSymbolicTranspose_SeqAIJ(R,&rti,&rtj);CHKERRQ(ierr);
52   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,R->cmap->n,R->rmap->n,rti,rtj,NULL,&P);CHKERRQ(ierr);
53 
54   /* get symbolic C=Pt*A*P */
55   ierr           = MatPtAPSymbolic_SeqAIJ_SeqAIJ_SparseAxpy(A,P,fill,C);CHKERRQ(ierr);
56   (*C)->rmap->bs = R->rmap->bs;
57   (*C)->cmap->bs = R->rmap->bs;
58   (*C)->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart;
59 
60   /* create a supporting struct */
61   ierr    = PetscNew(Mat_RARt,&rart);CHKERRQ(ierr);
62   c       = (Mat_SeqAIJ*)(*C)->data;
63   c->rart = rart;
64 
65   /* ------ Use coloring ---------- */
66   /* inode causes memory problem, don't know why */
67   if (c->inode.use) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"MAT_USE_INODES is not supported. Use '-mat_no_inode'");
68 
69   /* Create MatTransposeColoring from symbolic C=R*A*R^T */
70   ierr = MatColoringCreate(*C,&coloring);CHKERRQ(ierr);
71   ierr = MatColoringSetDistance(coloring,2);CHKERRQ(ierr);
72   ierr = MatColoringSetType(coloring,MATCOLORINGSL);CHKERRQ(ierr);
73   ierr = MatColoringSetFromOptions(coloring);CHKERRQ(ierr);
74   ierr = MatColoringApply(coloring,&iscoloring);CHKERRQ(ierr);
75   ierr = MatColoringDestroy(&coloring);CHKERRQ(ierr);
76   ierr = MatTransposeColoringCreate(*C,iscoloring,&matcoloring);CHKERRQ(ierr);
77 
78   rart->matcoloring = matcoloring;
79   ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
80 
81   /* Create Rt_dense */
82   ierr = MatCreate(PETSC_COMM_SELF,&Rt_dense);CHKERRQ(ierr);
83   ierr = MatSetSizes(Rt_dense,A->cmap->n,matcoloring->ncolors,A->cmap->n,matcoloring->ncolors);CHKERRQ(ierr);
84   ierr = MatSetType(Rt_dense,MATSEQDENSE);CHKERRQ(ierr);
85   ierr = MatSeqDenseSetPreallocation(Rt_dense,NULL);CHKERRQ(ierr);
86 
87   Rt_dense->assembled = PETSC_TRUE;
88   rart->Rt            = Rt_dense;
89 
90   /* Create RARt_dense = R*A*Rt_dense */
91   ierr = MatCreate(PETSC_COMM_SELF,&RARt_dense);CHKERRQ(ierr);
92   ierr = MatSetSizes(RARt_dense,(*C)->rmap->n,matcoloring->ncolors,(*C)->rmap->n,matcoloring->ncolors);CHKERRQ(ierr);
93   ierr = MatSetType(RARt_dense,MATSEQDENSE);CHKERRQ(ierr);
94   ierr = MatSeqDenseSetPreallocation(RARt_dense,NULL);CHKERRQ(ierr);
95 
96   rart->RARt = RARt_dense;
97 
98   /* Allocate work array to store columns of A*R^T used in MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense() */
99   ierr = PetscMalloc(A->rmap->n*4*sizeof(PetscScalar),&rart->work);CHKERRQ(ierr);
100 
101   rart->destroy      = (*C)->ops->destroy;
102   (*C)->ops->destroy = MatDestroy_SeqAIJ_RARt;
103 
104   /* clean up */
105   ierr = MatRestoreSymbolicTranspose_SeqAIJ(R,&rti,&rtj);CHKERRQ(ierr);
106   ierr = MatDestroy(&P);CHKERRQ(ierr);
107 
108 #if defined(PETSC_USE_INFO)
109   {
110     PetscReal density= (PetscReal)(c->nz)/(RARt_dense->rmap->n*RARt_dense->cmap->n);
111     ierr = PetscInfo(*C,"C=R*(A*Rt) via coloring C - use sparse-dense inner products\n");CHKERRQ(ierr);
112     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);
113   }
114 #endif
115   PetscFunctionReturn(0);
116 }
117 
118 /*
119  RAB = R * A * B, R and A in seqaij format, B in dense format;
120 */
121 #undef __FUNCT__
122 #define __FUNCT__ "MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense"
123 PetscErrorCode MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(Mat R,Mat A,Mat B,Mat RAB,PetscScalar *work)
124 {
125   Mat_SeqAIJ     *a=(Mat_SeqAIJ*)A->data,*r=(Mat_SeqAIJ*)R->data;
126   PetscErrorCode ierr;
127   PetscScalar    *b,r1,r2,r3,r4,*b1,*b2,*b3,*b4;
128   MatScalar      *aa,*ra;
129   PetscInt       cn =B->cmap->n,bm=B->rmap->n,col,i,j,n,*ai=a->i,*aj,am=A->rmap->n;
130   PetscInt       am2=2*am,am3=3*am,bm4=4*bm;
131   PetscScalar    *d,*c,*c2,*c3,*c4;
132   PetscInt       *rj,rm=R->rmap->n,dm=RAB->rmap->n,dn=RAB->cmap->n;
133   PetscInt       rm2=2*rm,rm3=3*rm,colrm;
134 
135   PetscFunctionBegin;
136   if (!dm || !dn) PetscFunctionReturn(0);
137   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);
138   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);
139   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);
140   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);
141 
142   { /*
143      This approach is not as good as original ones (will be removed later), but it reveals that
144      AB_den=A*B takes almost all execution time in R*A*B for src/ksp/ksp/examples/tutorials/ex56.c
145      */
146     PetscBool via_matmatmult=PETSC_FALSE;
147     ierr = PetscOptionsGetBool(NULL,"-matrart_via_matmatmult",&via_matmatmult,NULL);CHKERRQ(ierr);
148     if (via_matmatmult) {
149       Mat AB_den;
150       ierr = MatMatMultSymbolic_SeqAIJ_SeqDense(A,B,0.0,&AB_den);CHKERRQ(ierr);
151       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(A,B,AB_den);CHKERRQ(ierr);
152       ierr = MatMatMultNumeric_SeqAIJ_SeqDense(R,AB_den,RAB);CHKERRQ(ierr);
153       ierr = MatDestroy(&AB_den);CHKERRQ(ierr);
154       PetscFunctionReturn(0);
155     }
156   }
157 
158   ierr = MatDenseGetArray(B,&b);CHKERRQ(ierr);
159   ierr = MatDenseGetArray(RAB,&d);CHKERRQ(ierr);
160   b1   = b; b2 = b1 + bm; b3 = b2 + bm; b4 = b3 + bm;
161   c    = work; c2 = c + am; c3 = c2 + am; c4 = c3 + am;
162   for (col=0; col<cn-4; col += 4) {  /* over columns of C */
163     for (i=0; i<am; i++) {        /* over rows of A in those columns */
164       r1 = r2 = r3 = r4 = 0.0;
165       n  = ai[i+1] - ai[i];
166       aj = a->j + ai[i];
167       aa = a->a + ai[i];
168       for (j=0; j<n; j++) {
169         r1 += (*aa)*b1[*aj];
170         r2 += (*aa)*b2[*aj];
171         r3 += (*aa)*b3[*aj];
172         r4 += (*aa++)*b4[*aj++];
173       }
174       c[i]       = r1;
175       c[am  + i] = r2;
176       c[am2 + i] = r3;
177       c[am3 + i] = r4;
178     }
179     b1 += bm4;
180     b2 += bm4;
181     b3 += bm4;
182     b4 += bm4;
183 
184     /* RAB[:,col] = R*C[:,col] */
185     colrm = col*rm;
186     for (i=0; i<rm; i++) {        /* over rows of R in those columns */
187       r1 = r2 = r3 = r4 = 0.0;
188       n  = r->i[i+1] - r->i[i];
189       rj = r->j + r->i[i];
190       ra = r->a + r->i[i];
191       for (j=0; j<n; j++) {
192         r1 += (*ra)*c[*rj];
193         r2 += (*ra)*c2[*rj];
194         r3 += (*ra)*c3[*rj];
195         r4 += (*ra++)*c4[*rj++];
196       }
197       d[colrm + i]       = r1;
198       d[colrm + rm + i]  = r2;
199       d[colrm + rm2 + i] = r3;
200       d[colrm + rm3 + i] = r4;
201     }
202   }
203   for (; col<cn; col++) {     /* over extra columns of C */
204     for (i=0; i<am; i++) {  /* over rows of A in those columns */
205       r1 = 0.0;
206       n  = a->i[i+1] - a->i[i];
207       aj = a->j + a->i[i];
208       aa = a->a + a->i[i];
209       for (j=0; j<n; j++) {
210         r1 += (*aa++)*b1[*aj++];
211       }
212       c[i] = r1;
213     }
214     b1 += bm;
215 
216     for (i=0; i<rm; i++) {  /* over rows of R in those columns */
217       r1 = 0.0;
218       n  = r->i[i+1] - r->i[i];
219       rj = r->j + r->i[i];
220       ra = r->a + r->i[i];
221       for (j=0; j<n; j++) {
222         r1 += (*ra++)*c[*rj++];
223       }
224       d[col*rm + i] = r1;
225     }
226   }
227   ierr = PetscLogFlops(cn*2.0*(a->nz + r->nz));CHKERRQ(ierr);
228 
229   ierr = MatDenseRestoreArray(B,&b);CHKERRQ(ierr);
230   ierr = MatDenseRestoreArray(RAB,&d);CHKERRQ(ierr);
231   ierr = MatAssemblyBegin(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
232   ierr = MatAssemblyEnd(RAB,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
233   PetscFunctionReturn(0);
234 }
235 
236 #undef __FUNCT__
237 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart"
238 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_colorrart(Mat A,Mat R,Mat C)
239 {
240   PetscErrorCode       ierr;
241   Mat_SeqAIJ           *c = (Mat_SeqAIJ*)C->data;
242   Mat_RARt             *rart=c->rart;
243   MatTransposeColoring matcoloring;
244   Mat                  Rt,RARt;
245 
246   PetscFunctionBegin;
247   /* Get dense Rt by Apply MatTransposeColoring to R */
248   matcoloring = rart->matcoloring;
249   Rt          = rart->Rt;
250   ierr  = MatTransColoringApplySpToDen(matcoloring,R,Rt);CHKERRQ(ierr);
251 
252   /* Get dense RARt = R*A*Rt -- dominates! */
253   RARt = rart->RARt;
254   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqDense(R,A,Rt,RARt,rart->work);CHKERRQ(ierr);
255 
256   /* Recover C from C_dense */
257   ierr = MatTransColoringApplyDenToSp(matcoloring,RARt,C);CHKERRQ(ierr);
258   PetscFunctionReturn(0);
259 }
260 
261 #undef __FUNCT__
262 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult"
263 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,PetscReal fill,Mat *C)
264 {
265   PetscErrorCode  ierr;
266   Mat             ARt,RARt;
267   Mat_SeqAIJ     *c;
268   Mat_RARt       *rart;
269 
270   PetscFunctionBegin;
271   /* must use '-mat_no_inode' with '-matmattransmult_color 1' - do not knwo why? */
272   ierr = MatMatTransposeMultSymbolic_SeqAIJ_SeqAIJ(A,R,fill,&ARt);CHKERRQ(ierr);
273   ierr = MatMatMultSymbolic_SeqAIJ_SeqAIJ(R,ARt,fill,&RARt);CHKERRQ(ierr);
274   *C                     = RARt;
275   RARt->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult;
276 
277   ierr = PetscNew(Mat_RARt,&rart);CHKERRQ(ierr);
278   c         = (Mat_SeqAIJ*)(*C)->data;
279   c->rart   = rart;
280   rart->ARt = ARt;
281   rart->destroy      = RARt->ops->destroy;
282   RARt->ops->destroy = MatDestroy_SeqAIJ_RARt;
283 #if defined(PETSC_USE_INFO)
284   ierr = PetscInfo(*C,"Use ARt=A*R^T, C=R*ARt via MatMatTransposeMult(). Coloring can be applied to A*R^T.\n");CHKERRQ(ierr);
285 #endif
286   PetscFunctionReturn(0);
287 }
288 
289 #undef __FUNCT__
290 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult"
291 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ_matmattransposemult(Mat A,Mat R,Mat C)
292 {
293   PetscErrorCode  ierr;
294   Mat_SeqAIJ      *c=(Mat_SeqAIJ*)C->data;
295   Mat_RARt        *rart=c->rart;
296   Mat             ARt=rart->ARt;
297 
298   PetscFunctionBegin;
299   ierr = MatMatTransposeMultNumeric_SeqAIJ_SeqAIJ(A,R,ARt);CHKERRQ(ierr); /* dominate! */
300   ierr = MatMatMultNumeric_SeqAIJ_SeqAIJ(R,ARt,C);CHKERRQ(ierr);
301   PetscFunctionReturn(0);
302 }
303 
304 #undef __FUNCT__
305 #define __FUNCT__ "MatRARtSymbolic_SeqAIJ_SeqAIJ"
306 PetscErrorCode MatRARtSymbolic_SeqAIJ_SeqAIJ(Mat A,Mat R,PetscReal fill,Mat *C)
307 {
308   PetscErrorCode  ierr;
309   Mat             Rt;
310   Mat_SeqAIJ      *c;
311   Mat_RARt        *rart;
312 
313   PetscFunctionBegin;
314   ierr = MatTranspose_SeqAIJ(R,MAT_INITIAL_MATRIX,&Rt);CHKERRQ(ierr);
315   ierr = MatMatMatMultSymbolic_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,fill,C);CHKERRQ(ierr);
316 
317   ierr = PetscNew(Mat_RARt,&rart);CHKERRQ(ierr);
318   rart->Rt = Rt;
319   c        = (Mat_SeqAIJ*)(*C)->data;
320   c->rart  = rart;
321   rart->destroy          = (*C)->ops->destroy;
322   (*C)->ops->destroy     = MatDestroy_SeqAIJ_RARt;
323   (*C)->ops->rartnumeric = MatRARtNumeric_SeqAIJ_SeqAIJ;
324 #if defined(PETSC_USE_INFO)
325   ierr = PetscInfo(*C,"Use Rt=R^T and C=R*A*Rt via MatMatMatMult() to avoid sparse inner products\n");CHKERRQ(ierr);
326 #endif
327   PetscFunctionReturn(0);
328 }
329 
330 #undef __FUNCT__
331 #define __FUNCT__ "MatRARtNumeric_SeqAIJ_SeqAIJ"
332 PetscErrorCode MatRARtNumeric_SeqAIJ_SeqAIJ(Mat A,Mat R,Mat C)
333 {
334   PetscErrorCode  ierr;
335   Mat_SeqAIJ      *c = (Mat_SeqAIJ*)C->data;
336   Mat_RARt        *rart = c->rart;
337   Mat             Rt = rart->Rt;
338 
339   PetscFunctionBegin;
340   ierr = MatTranspose_SeqAIJ(R,MAT_REUSE_MATRIX,&Rt);CHKERRQ(ierr);
341   ierr = MatMatMatMultNumeric_SeqAIJ_SeqAIJ_SeqAIJ(R,A,Rt,C);CHKERRQ(ierr);
342   PetscFunctionReturn(0);
343 }
344 
345 #undef __FUNCT__
346 #define __FUNCT__ "MatRARt_SeqAIJ_SeqAIJ"
347 PetscErrorCode MatRARt_SeqAIJ_SeqAIJ(Mat A,Mat R,MatReuse scall,PetscReal fill,Mat *C)
348 {
349   PetscErrorCode ierr;
350   const char     *algTypes[3] = {"matmatmatmult","matmattransposemult","coloring_rart"};
351   PetscInt       alg=0; /* set default algorithm */
352 
353   PetscFunctionBegin;
354   if (scall == MAT_INITIAL_MATRIX) {
355     ierr = PetscObjectOptionsBegin((PetscObject)A);CHKERRQ(ierr);
356     ierr = PetscOptionsEList("-matrart_via","Algorithmic approach","MatRARt",algTypes,3,algTypes[0],&alg,NULL);CHKERRQ(ierr);
357     ierr = PetscOptionsEnd();CHKERRQ(ierr);
358 
359     ierr = PetscLogEventBegin(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
360     switch (alg) {
361     case 1:
362       /* via matmattransposemult: ARt=A*R^T, C=R*ARt - matrix coloring can be applied to A*R^T */
363       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_matmattransposemult(A,R,fill,C);CHKERRQ(ierr);
364       break;
365     case 2:
366       /* via coloring_rart: apply coloring C = R*A*R^T                          */
367       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ_colorrart(A,R,fill,C);CHKERRQ(ierr);
368       break;
369     default:
370       /* via matmatmatmult: Rt=R^T, C=R*A*Rt - avoid inefficient sparse inner products */
371       ierr = MatRARtSymbolic_SeqAIJ_SeqAIJ(A,R,fill,C);CHKERRQ(ierr);
372       break;
373     }
374     ierr = PetscLogEventEnd(MAT_RARtSymbolic,A,R,0,0);CHKERRQ(ierr);
375   }
376 
377   ierr = PetscLogEventBegin(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
378   ierr = (*(*C)->ops->rartnumeric)(A,R,*C);CHKERRQ(ierr);
379   ierr = PetscLogEventEnd(MAT_RARtNumeric,A,R,0,0);CHKERRQ(ierr);
380   PetscFunctionReturn(0);
381 }
382