xref: /petsc/src/mat/impls/htool/htool.cxx (revision 5c6496ba940341816c82c3b7fcda2e06e7ddfa20)
1 #include <../src/mat/impls/htool/htool.hpp> /*I "petscmat.h" I*/
2 #include <petscblaslapack.h>
3 #include <set>
4 
5 #define ALEN(a) (sizeof(a)/sizeof((a)[0]))
6 const char *const MatHtoolCompressorTypes[] = { "sympartialACA", "fullACA", "SVD" };
7 const char *const MatHtoolClusteringTypes[] = { "PCARegular", "PCAGeometric", "BoundingBox1Regular", "BoundingBox1Geometric" };
8 const char HtoolCitation[] = "@article{marchand2020two,\n"
9 "  Author = {Marchand, Pierre and Claeys, Xavier and Jolivet, Pierre and Nataf, Fr\\'ed\\'eric and Tournier, Pierre-Henri},\n"
10 "  Title = {Two-level preconditioning for $h$-version boundary element approximation of hypersingular operator with {GenEO}},\n"
11 "  Year = {2020},\n"
12 "  Publisher = {Elsevier},\n"
13 "  Journal = {Numerische Mathematik},\n"
14 "  Volume = {146},\n"
15 "  Pages = {597--628},\n"
16 "  Url = {https://github.com/htool-ddm/htool}\n"
17 "}\n";
18 static PetscBool HtoolCite = PETSC_FALSE;
19 
20 static PetscErrorCode MatGetDiagonal_Htool(Mat A,Vec v)
21 {
22   Mat_Htool      *a = (Mat_Htool*)A->data;
23   PetscScalar    *x;
24   PetscBool      flg;
25   PetscErrorCode ierr;
26 
27   PetscFunctionBegin;
28   ierr = MatHasCongruentLayouts(A,&flg);CHKERRQ(ierr);
29   PetscCheckFalse(!flg,PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"Only congruent layouts supported");
30   ierr = VecGetArrayWrite(v,&x);CHKERRQ(ierr);
31   a->hmatrix->copy_local_diagonal(x);
32   ierr = VecRestoreArrayWrite(v,&x);CHKERRQ(ierr);
33   ierr = VecScale(v,a->s);CHKERRQ(ierr);
34   PetscFunctionReturn(0);
35 }
36 
37 static PetscErrorCode MatGetDiagonalBlock_Htool(Mat A,Mat *b)
38 {
39   Mat_Htool      *a = (Mat_Htool*)A->data;
40   Mat            B;
41   PetscScalar    *ptr;
42   PetscBool      flg;
43   PetscErrorCode ierr;
44 
45   PetscFunctionBegin;
46   ierr = MatHasCongruentLayouts(A,&flg);CHKERRQ(ierr);
47   PetscCheckFalse(!flg,PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"Only congruent layouts supported");
48   ierr = PetscObjectQuery((PetscObject)A,"DiagonalBlock",(PetscObject*)&B);CHKERRQ(ierr); /* same logic as in MatGetDiagonalBlock_MPIDense() */
49   if (!B) {
50     ierr = MatCreateDense(PETSC_COMM_SELF,A->rmap->n,A->rmap->n,A->rmap->n,A->rmap->n,NULL,&B);CHKERRQ(ierr);
51     ierr = MatDenseGetArrayWrite(B,&ptr);CHKERRQ(ierr);
52     a->hmatrix->copy_local_diagonal_block(ptr);
53     ierr = MatDenseRestoreArrayWrite(B,&ptr);CHKERRQ(ierr);
54     ierr = MatPropagateSymmetryOptions(A,B);CHKERRQ(ierr);
55     ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
56     ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
57     ierr = MatScale(B,a->s);CHKERRQ(ierr);
58     ierr = PetscObjectCompose((PetscObject)A,"DiagonalBlock",(PetscObject)B);CHKERRQ(ierr);
59     *b   = B;
60     ierr = MatDestroy(&B);CHKERRQ(ierr);
61   } else *b = B;
62   PetscFunctionReturn(0);
63 }
64 
65 static PetscErrorCode MatMult_Htool(Mat A,Vec x,Vec y)
66 {
67   Mat_Htool         *a = (Mat_Htool*)A->data;
68   const PetscScalar *in;
69   PetscScalar       *out;
70   PetscErrorCode    ierr;
71 
72   PetscFunctionBegin;
73   ierr = VecGetArrayRead(x,&in);CHKERRQ(ierr);
74   ierr = VecGetArrayWrite(y,&out);CHKERRQ(ierr);
75   a->hmatrix->mvprod_local_to_local(in,out);
76   ierr = VecRestoreArrayRead(x,&in);CHKERRQ(ierr);
77   ierr = VecRestoreArrayWrite(y,&out);CHKERRQ(ierr);
78   ierr = VecScale(y,a->s);CHKERRQ(ierr);
79   PetscFunctionReturn(0);
80 }
81 
82 /* naive implementation of MatMultAdd() needed for FEM-BEM coupling via MATNEST */
83 static PetscErrorCode MatMultAdd_Htool(Mat A,Vec v1,Vec v2,Vec v3)
84 {
85   Mat_Htool         *a = (Mat_Htool*)A->data;
86   Vec               tmp;
87   const PetscScalar scale = a->s;
88   PetscErrorCode    ierr;
89 
90   PetscFunctionBegin;
91   ierr = VecDuplicate(v2,&tmp);CHKERRQ(ierr);
92   ierr = VecCopy(v2,v3);CHKERRQ(ierr); /* no-op in MatMultAdd(bA->m[i][j],bx[j],by[i],by[i]) since VecCopy() checks for x == y */
93   a->s = 1.0; /* set s to 1.0 since VecAXPY() may be used to scale the MatMult() output Vec */
94   ierr = MatMult_Htool(A,v1,tmp);CHKERRQ(ierr);
95   ierr = VecAXPY(v3,scale,tmp);CHKERRQ(ierr);
96   ierr = VecDestroy(&tmp);CHKERRQ(ierr);
97   a->s = scale; /* set s back to its original value */
98   PetscFunctionReturn(0);
99 }
100 
101 static PetscErrorCode MatMultTranspose_Htool(Mat A,Vec x,Vec y)
102 {
103   Mat_Htool         *a = (Mat_Htool*)A->data;
104   const PetscScalar *in;
105   PetscScalar       *out;
106   PetscErrorCode    ierr;
107 
108   PetscFunctionBegin;
109   ierr = VecGetArrayRead(x,&in);CHKERRQ(ierr);
110   ierr = VecGetArrayWrite(y,&out);CHKERRQ(ierr);
111   a->hmatrix->mvprod_transp_local_to_local(in,out);
112   ierr = VecRestoreArrayRead(x,&in);CHKERRQ(ierr);
113   ierr = VecRestoreArrayWrite(y,&out);CHKERRQ(ierr);
114   ierr = VecScale(y,a->s);CHKERRQ(ierr);
115   PetscFunctionReturn(0);
116 }
117 
118 static PetscErrorCode MatIncreaseOverlap_Htool(Mat A,PetscInt is_max,IS is[],PetscInt ov)
119 {
120   std::set<PetscInt> set;
121   const PetscInt     *idx;
122   PetscInt           *oidx,size,bs[2];
123   PetscMPIInt        csize;
124   PetscErrorCode     ierr;
125 
126   PetscFunctionBegin;
127   ierr = MatGetBlockSizes(A,bs,bs+1);CHKERRQ(ierr);
128   if (bs[0] != bs[1]) bs[0] = 1;
129   for (PetscInt i=0; i<is_max; ++i) {
130     /* basic implementation that adds indices by shifting an IS by -ov, -ov+1..., -1, 1..., ov-1, ov */
131     /* needed to avoid subdomain matrices to replicate A since it is dense                           */
132     ierr = MPI_Comm_size(PetscObjectComm((PetscObject)is[i]),&csize);CHKERRMPI(ierr);
133     PetscCheckFalse(csize != 1,PETSC_COMM_SELF,PETSC_ERR_SUP,"Unsupported parallel IS");
134     ierr = ISGetSize(is[i],&size);CHKERRQ(ierr);
135     ierr = ISGetIndices(is[i],&idx);CHKERRQ(ierr);
136     for (PetscInt j=0; j<size; ++j) {
137       set.insert(idx[j]);
138       for (PetscInt k=1; k<=ov; ++k) {               /* for each layer of overlap      */
139         if (idx[j] - k >= 0) set.insert(idx[j] - k); /* do not insert negative indices */
140         if (idx[j] + k < A->rmap->N && idx[j] + k < A->cmap->N) set.insert(idx[j] + k); /* do not insert indices greater than the dimension of A */
141       }
142     }
143     ierr = ISRestoreIndices(is[i],&idx);CHKERRQ(ierr);
144     ierr = ISDestroy(is+i);CHKERRQ(ierr);
145     if (bs[0] > 1) {
146       for (std::set<PetscInt>::iterator it=set.cbegin(); it!=set.cend(); it++) {
147         std::vector<PetscInt> block(bs[0]);
148         std::iota(block.begin(),block.end(),(*it/bs[0])*bs[0]);
149         set.insert(block.cbegin(),block.cend());
150       }
151     }
152     size = set.size(); /* size with overlap */
153     ierr = PetscMalloc1(size,&oidx);CHKERRQ(ierr);
154     for (const PetscInt j : set) *oidx++ = j;
155     oidx -= size;
156     ierr = ISCreateGeneral(PETSC_COMM_SELF,size,oidx,PETSC_OWN_POINTER,is+i);CHKERRQ(ierr);
157   }
158   PetscFunctionReturn(0);
159 }
160 
161 static PetscErrorCode MatCreateSubMatrices_Htool(Mat A,PetscInt n,const IS irow[],const IS icol[],MatReuse scall,Mat *submat[])
162 {
163   Mat_Htool         *a = (Mat_Htool*)A->data;
164   Mat               D,B,BT;
165   const PetscScalar *copy;
166   PetscScalar       *ptr;
167   const PetscInt    *idxr,*idxc,*it;
168   PetscInt          nrow,m,i;
169   PetscBool         flg;
170   PetscErrorCode    ierr;
171 
172   PetscFunctionBegin;
173   if (scall != MAT_REUSE_MATRIX) {
174     ierr = PetscCalloc1(n,submat);CHKERRQ(ierr);
175   }
176   for (i=0; i<n; ++i) {
177     ierr = ISGetLocalSize(irow[i],&nrow);CHKERRQ(ierr);
178     ierr = ISGetLocalSize(icol[i],&m);CHKERRQ(ierr);
179     ierr = ISGetIndices(irow[i],&idxr);CHKERRQ(ierr);
180     ierr = ISGetIndices(icol[i],&idxc);CHKERRQ(ierr);
181     if (scall != MAT_REUSE_MATRIX) {
182       ierr = MatCreateDense(PETSC_COMM_SELF,nrow,m,nrow,m,NULL,(*submat)+i);CHKERRQ(ierr);
183     }
184     ierr = MatDenseGetArrayWrite((*submat)[i],&ptr);CHKERRQ(ierr);
185     if (irow[i] == icol[i]) { /* same row and column IS? */
186       ierr = MatHasCongruentLayouts(A,&flg);CHKERRQ(ierr);
187       if (flg) {
188         ierr = ISSorted(irow[i],&flg);CHKERRQ(ierr);
189         if (flg) { /* sorted IS? */
190           it = std::lower_bound(idxr,idxr+nrow,A->rmap->rstart);
191           if (it != idxr+nrow && *it == A->rmap->rstart) { /* rmap->rstart in IS? */
192             if (std::distance(idxr,it) + A->rmap->n <= nrow) { /* long enough IS to store the local diagonal block? */
193               for (PetscInt j=0; j<A->rmap->n && flg; ++j) if (PetscUnlikely(it[j] != A->rmap->rstart+j)) flg = PETSC_FALSE;
194               if (flg) { /* complete local diagonal block in IS? */
195                 /* fast extraction when the local diagonal block is part of the submatrix, e.g., for PCASM or PCHPDDM
196                  *      [   B   C   E   ]
197                  *  A = [   B   D   E   ]
198                  *      [   B   F   E   ]
199                  */
200                 m = std::distance(idxr,it); /* shift of the coefficient (0,0) of block D from above */
201                 ierr = MatGetDiagonalBlock_Htool(A,&D);CHKERRQ(ierr);
202                 ierr = MatDenseGetArrayRead(D,&copy);CHKERRQ(ierr);
203                 for (PetscInt k=0; k<A->rmap->n; ++k) {
204                   ierr = PetscArraycpy(ptr+(m+k)*nrow+m,copy+k*A->rmap->n,A->rmap->n);CHKERRQ(ierr); /* block D from above */
205                 }
206                 ierr = MatDenseRestoreArrayRead(D,&copy);CHKERRQ(ierr);
207                 if (m) {
208                   a->wrapper->copy_submatrix(nrow,m,idxr,idxc,ptr); /* vertical block B from above */
209                   /* entry-wise assembly may be costly, so transpose already-computed entries when possible */
210                   if (A->symmetric || A->hermitian) {
211                     ierr = MatCreateDense(PETSC_COMM_SELF,A->rmap->n,m,A->rmap->n,m,ptr+m,&B);CHKERRQ(ierr);
212                     ierr = MatDenseSetLDA(B,nrow);CHKERRQ(ierr);
213                     ierr = MatCreateDense(PETSC_COMM_SELF,m,A->rmap->n,m,A->rmap->n,ptr+m*nrow,&BT);CHKERRQ(ierr);
214                     ierr = MatDenseSetLDA(BT,nrow);CHKERRQ(ierr);
215                     if (A->hermitian && PetscDefined(USE_COMPLEX)) {
216                       ierr = MatHermitianTranspose(B,MAT_REUSE_MATRIX,&BT);CHKERRQ(ierr);
217                     } else {
218                       ierr = MatTranspose(B,MAT_REUSE_MATRIX,&BT);CHKERRQ(ierr);
219                     }
220                     ierr = MatDestroy(&B);CHKERRQ(ierr);
221                     ierr = MatDestroy(&BT);CHKERRQ(ierr);
222                   } else {
223                     for (PetscInt k=0; k<A->rmap->n; ++k) { /* block C from above */
224                       a->wrapper->copy_submatrix(m,1,idxr,idxc+m+k,ptr+(m+k)*nrow);
225                     }
226                   }
227                 }
228                 if (m+A->rmap->n != nrow) {
229                   a->wrapper->copy_submatrix(nrow,std::distance(it+A->rmap->n,idxr+nrow),idxr,idxc+m+A->rmap->n,ptr+(m+A->rmap->n)*nrow); /* vertical block E from above */
230                   /* entry-wise assembly may be costly, so transpose already-computed entries when possible */
231                   if (A->symmetric || A->hermitian) {
232                     ierr = MatCreateDense(PETSC_COMM_SELF,A->rmap->n,nrow-(m+A->rmap->n),A->rmap->n,nrow-(m+A->rmap->n),ptr+(m+A->rmap->n)*nrow+m,&B);CHKERRQ(ierr);
233                     ierr = MatDenseSetLDA(B,nrow);CHKERRQ(ierr);
234                     ierr = MatCreateDense(PETSC_COMM_SELF,nrow-(m+A->rmap->n),A->rmap->n,nrow-(m+A->rmap->n),A->rmap->n,ptr+m*nrow+m+A->rmap->n,&BT);CHKERRQ(ierr);
235                     ierr = MatDenseSetLDA(BT,nrow);CHKERRQ(ierr);
236                     if (A->hermitian && PetscDefined(USE_COMPLEX)) {
237                       ierr = MatHermitianTranspose(B,MAT_REUSE_MATRIX,&BT);CHKERRQ(ierr);
238                     } else {
239                       ierr = MatTranspose(B,MAT_REUSE_MATRIX,&BT);CHKERRQ(ierr);
240                     }
241                     ierr = MatDestroy(&B);CHKERRQ(ierr);
242                     ierr = MatDestroy(&BT);CHKERRQ(ierr);
243                   } else {
244                     for (PetscInt k=0; k<A->rmap->n; ++k) { /* block F from above */
245                       a->wrapper->copy_submatrix(std::distance(it+A->rmap->n,idxr+nrow),1,it+A->rmap->n,idxc+m+k,ptr+(m+k)*nrow+m+A->rmap->n);
246                     }
247                   }
248                 }
249               } /* complete local diagonal block not in IS */
250             } else flg = PETSC_FALSE; /* IS not long enough to store the local diagonal block */
251           } else flg = PETSC_FALSE; /* rmap->rstart not in IS */
252         } /* unsorted IS */
253       }
254     } else flg = PETSC_FALSE; /* different row and column IS */
255     if (!flg) a->wrapper->copy_submatrix(nrow,m,idxr,idxc,ptr); /* reassemble everything */
256     ierr = ISRestoreIndices(irow[i],&idxr);CHKERRQ(ierr);
257     ierr = ISRestoreIndices(icol[i],&idxc);CHKERRQ(ierr);
258     ierr = MatDenseRestoreArrayWrite((*submat)[i],&ptr);CHKERRQ(ierr);
259     ierr = MatAssemblyBegin((*submat)[i],MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
260     ierr = MatAssemblyEnd((*submat)[i],MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
261     ierr = MatScale((*submat)[i],a->s);CHKERRQ(ierr);
262   }
263   PetscFunctionReturn(0);
264 }
265 
266 static PetscErrorCode MatDestroy_Htool(Mat A)
267 {
268   Mat_Htool               *a = (Mat_Htool*)A->data;
269   PetscContainer          container;
270   MatHtoolKernelTranspose *kernelt;
271   PetscErrorCode          ierr;
272 
273   PetscFunctionBegin;
274   ierr = PetscObjectChangeTypeName((PetscObject)A,NULL);CHKERRQ(ierr);
275   ierr = PetscObjectComposeFunction((PetscObject)A,"MatProductSetFromOptions_htool_seqdense_C",NULL);CHKERRQ(ierr);
276   ierr = PetscObjectComposeFunction((PetscObject)A,"MatProductSetFromOptions_htool_mpidense_C",NULL);CHKERRQ(ierr);
277   ierr = PetscObjectComposeFunction((PetscObject)A,"MatConvert_htool_seqdense_C",NULL);CHKERRQ(ierr);
278   ierr = PetscObjectComposeFunction((PetscObject)A,"MatConvert_htool_mpidense_C",NULL);CHKERRQ(ierr);
279   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolGetHierarchicalMat_C",NULL);CHKERRQ(ierr);
280   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolSetKernel_C",NULL);CHKERRQ(ierr);
281   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolGetPermutationSource_C",NULL);CHKERRQ(ierr);
282   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolGetPermutationTarget_C",NULL);CHKERRQ(ierr);
283   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolUsePermutation_C",NULL);CHKERRQ(ierr);
284   ierr = PetscObjectQuery((PetscObject)A,"KernelTranspose",(PetscObject*)&container);CHKERRQ(ierr);
285   if (container) { /* created in MatTranspose_Htool() */
286     ierr = PetscContainerGetPointer(container,(void**)&kernelt);CHKERRQ(ierr);
287     ierr = MatDestroy(&kernelt->A);CHKERRQ(ierr);
288     ierr = PetscFree(kernelt);CHKERRQ(ierr);
289     ierr = PetscContainerDestroy(&container);CHKERRQ(ierr);
290     ierr = PetscObjectCompose((PetscObject)A,"KernelTranspose",NULL);CHKERRQ(ierr);
291   }
292   if (a->gcoords_source != a->gcoords_target) {
293     ierr = PetscFree(a->gcoords_source);CHKERRQ(ierr);
294   }
295   ierr = PetscFree(a->gcoords_target);CHKERRQ(ierr);
296   ierr = PetscFree2(a->work_source,a->work_target);CHKERRQ(ierr);
297   delete a->wrapper;
298   delete a->hmatrix;
299   ierr = PetscFree(A->data);CHKERRQ(ierr);
300   PetscFunctionReturn(0);
301 }
302 
303 static PetscErrorCode MatView_Htool(Mat A,PetscViewer pv)
304 {
305   Mat_Htool      *a = (Mat_Htool*)A->data;
306   PetscBool      flg;
307   PetscErrorCode ierr;
308 
309   PetscFunctionBegin;
310   ierr = PetscObjectTypeCompare((PetscObject)pv,PETSCVIEWERASCII,&flg);CHKERRQ(ierr);
311   if (flg) {
312     ierr = PetscViewerASCIIPrintf(pv,"symmetry: %c\n",a->hmatrix->get_symmetry_type());CHKERRQ(ierr);
313     if (PetscAbsScalar(a->s-1.0) > PETSC_MACHINE_EPSILON) {
314 #if defined(PETSC_USE_COMPLEX)
315       ierr = PetscViewerASCIIPrintf(pv,"scaling: %g+%gi\n",(double)PetscRealPart(a->s),(double)PetscImaginaryPart(a->s));CHKERRQ(ierr);
316 #else
317       ierr = PetscViewerASCIIPrintf(pv,"scaling: %g\n",(double)a->s);CHKERRQ(ierr);
318 #endif
319     }
320     ierr = PetscViewerASCIIPrintf(pv,"minimum cluster size: %" PetscInt_FMT "\n",a->bs[0]);CHKERRQ(ierr);
321     ierr = PetscViewerASCIIPrintf(pv,"maximum block size: %" PetscInt_FMT "\n",a->bs[1]);CHKERRQ(ierr);
322     ierr = PetscViewerASCIIPrintf(pv,"epsilon: %g\n",(double)a->epsilon);CHKERRQ(ierr);
323     ierr = PetscViewerASCIIPrintf(pv,"eta: %g\n",(double)a->eta);CHKERRQ(ierr);
324     ierr = PetscViewerASCIIPrintf(pv,"minimum target depth: %" PetscInt_FMT "\n",a->depth[0]);CHKERRQ(ierr);
325     ierr = PetscViewerASCIIPrintf(pv,"minimum source depth: %" PetscInt_FMT "\n",a->depth[1]);CHKERRQ(ierr);
326     ierr = PetscViewerASCIIPrintf(pv,"compressor: %s\n",MatHtoolCompressorTypes[a->compressor]);CHKERRQ(ierr);
327     ierr = PetscViewerASCIIPrintf(pv,"clustering: %s\n",MatHtoolClusteringTypes[a->clustering]);CHKERRQ(ierr);
328     ierr = PetscViewerASCIIPrintf(pv,"compression ratio: %s\n",a->hmatrix->get_infos("Compression_ratio").c_str());CHKERRQ(ierr);
329     ierr = PetscViewerASCIIPrintf(pv,"space saving: %s\n",a->hmatrix->get_infos("Space_saving").c_str());CHKERRQ(ierr);
330     ierr = PetscViewerASCIIPrintf(pv,"number of dense (resp. low rank) matrices: %s (resp. %s)\n",a->hmatrix->get_infos("Number_of_dmat").c_str(),a->hmatrix->get_infos("Number_of_lrmat").c_str());CHKERRQ(ierr);
331     ierr = PetscViewerASCIIPrintf(pv,"(minimum, mean, maximum) dense block sizes: (%s, %s, %s)\n",a->hmatrix->get_infos("Dense_block_size_min").c_str(),a->hmatrix->get_infos("Dense_block_size_mean").c_str(),a->hmatrix->get_infos("Dense_block_size_max").c_str());CHKERRQ(ierr);
332     ierr = PetscViewerASCIIPrintf(pv,"(minimum, mean, maximum) low rank block sizes: (%s, %s, %s)\n",a->hmatrix->get_infos("Low_rank_block_size_min").c_str(),a->hmatrix->get_infos("Low_rank_block_size_mean").c_str(),a->hmatrix->get_infos("Low_rank_block_size_max").c_str());CHKERRQ(ierr);
333     ierr = PetscViewerASCIIPrintf(pv,"(minimum, mean, maximum) ranks: (%s, %s, %s)\n",a->hmatrix->get_infos("Rank_min").c_str(),a->hmatrix->get_infos("Rank_mean").c_str(),a->hmatrix->get_infos("Rank_max").c_str());CHKERRQ(ierr);
334   }
335   PetscFunctionReturn(0);
336 }
337 
338 static PetscErrorCode MatScale_Htool(Mat A,PetscScalar s)
339 {
340   Mat_Htool *a = (Mat_Htool*)A->data;
341 
342   PetscFunctionBegin;
343   a->s *= s;
344   PetscFunctionReturn(0);
345 }
346 
347 /* naive implementation of MatGetRow() needed for MatConvert_Nest_AIJ() */
348 static PetscErrorCode MatGetRow_Htool(Mat A,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
349 {
350   Mat_Htool      *a = (Mat_Htool*)A->data;
351   PetscInt       *idxc;
352   PetscBLASInt   one = 1,bn;
353   PetscErrorCode ierr;
354 
355   PetscFunctionBegin;
356   if (nz) *nz = A->cmap->N;
357   if (idx || v) { /* even if !idx, need to set idxc for htool::copy_submatrix() */
358     ierr = PetscMalloc1(A->cmap->N,&idxc);CHKERRQ(ierr);
359     for (PetscInt i=0; i<A->cmap->N; ++i) idxc[i] = i;
360   }
361   if (idx) *idx = idxc;
362   if (v) {
363     ierr = PetscMalloc1(A->cmap->N,v);CHKERRQ(ierr);
364     if (a->wrapper) a->wrapper->copy_submatrix(1,A->cmap->N,&row,idxc,*v);
365     else reinterpret_cast<htool::VirtualGenerator<PetscScalar>*>(a->kernelctx)->copy_submatrix(1,A->cmap->N,&row,idxc,*v);
366     ierr = PetscBLASIntCast(A->cmap->N,&bn);CHKERRQ(ierr);
367     PetscStackCallBLAS("BLASscal",BLASscal_(&bn,&a->s,*v,&one));
368   }
369   if (!idx) {
370     ierr = PetscFree(idxc);CHKERRQ(ierr);
371   }
372   PetscFunctionReturn(0);
373 }
374 
375 static PetscErrorCode MatRestoreRow_Htool(Mat A,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
376 {
377   PetscErrorCode ierr;
378 
379   PetscFunctionBegin;
380   if (nz) *nz = 0;
381   if (idx) {
382     ierr = PetscFree(*idx);CHKERRQ(ierr);
383   }
384   if (v) {
385     ierr = PetscFree(*v);CHKERRQ(ierr);
386   }
387   PetscFunctionReturn(0);
388 }
389 
390 static PetscErrorCode MatSetFromOptions_Htool(PetscOptionItems *PetscOptionsObject,Mat A)
391 {
392   Mat_Htool      *a = (Mat_Htool*)A->data;
393   PetscInt       n;
394   PetscBool      flg;
395   PetscErrorCode ierr;
396 
397   PetscFunctionBegin;
398   ierr = PetscOptionsHead(PetscOptionsObject,"Htool options");CHKERRQ(ierr);
399   ierr = PetscOptionsInt("-mat_htool_min_cluster_size","Minimal leaf size in cluster tree",NULL,a->bs[0],a->bs,NULL);CHKERRQ(ierr);
400   ierr = PetscOptionsInt("-mat_htool_max_block_size","Maximal number of coefficients in a dense block",NULL,a->bs[1],a->bs + 1,NULL);CHKERRQ(ierr);
401   ierr = PetscOptionsReal("-mat_htool_epsilon","Relative error in Frobenius norm when approximating a block",NULL,a->epsilon,&a->epsilon,NULL);CHKERRQ(ierr);
402   ierr = PetscOptionsReal("-mat_htool_eta","Admissibility condition tolerance",NULL,a->eta,&a->eta,NULL);CHKERRQ(ierr);
403   ierr = PetscOptionsInt("-mat_htool_min_target_depth","Minimal cluster tree depth associated with the rows",NULL,a->depth[0],a->depth,NULL);CHKERRQ(ierr);
404   ierr = PetscOptionsInt("-mat_htool_min_source_depth","Minimal cluster tree depth associated with the columns",NULL,a->depth[1],a->depth + 1,NULL);CHKERRQ(ierr);
405   n = 0;
406   ierr = PetscOptionsEList("-mat_htool_compressor","Type of compression","MatHtoolCompressorType",MatHtoolCompressorTypes,ALEN(MatHtoolCompressorTypes),MatHtoolCompressorTypes[MAT_HTOOL_COMPRESSOR_SYMPARTIAL_ACA],&n,&flg);CHKERRQ(ierr);
407   if (flg) a->compressor = MatHtoolCompressorType(n);
408   n = 0;
409   ierr = PetscOptionsEList("-mat_htool_clustering","Type of clustering","MatHtoolClusteringType",MatHtoolClusteringTypes,ALEN(MatHtoolClusteringTypes),MatHtoolClusteringTypes[MAT_HTOOL_CLUSTERING_PCA_REGULAR],&n,&flg);CHKERRQ(ierr);
410   if (flg) a->clustering = MatHtoolClusteringType(n);
411   ierr = PetscOptionsTail();CHKERRQ(ierr);
412   PetscFunctionReturn(0);
413 }
414 
415 static PetscErrorCode MatAssemblyEnd_Htool(Mat A,MatAssemblyType type)
416 {
417   Mat_Htool                                                    *a = (Mat_Htool*)A->data;
418   const PetscInt                                               *ranges;
419   PetscInt                                                     *offset;
420   PetscMPIInt                                                  size;
421   char                                                         S = PetscDefined(USE_COMPLEX) && A->hermitian ? 'H' : (A->symmetric ? 'S' : 'N'),uplo = S == 'N' ? 'N' : 'U';
422   htool::VirtualGenerator<PetscScalar>                         *generator = nullptr;
423   std::shared_ptr<htool::VirtualCluster>                       t,s = nullptr;
424   std::shared_ptr<htool::VirtualLowRankGenerator<PetscScalar>> compressor = nullptr;
425   PetscErrorCode                                               ierr;
426 
427   PetscFunctionBegin;
428   ierr = PetscCitationsRegister(HtoolCitation,&HtoolCite);CHKERRQ(ierr);
429   delete a->wrapper;
430   delete a->hmatrix;
431   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)A),&size);CHKERRMPI(ierr);
432   ierr = PetscMalloc1(2*size,&offset);CHKERRQ(ierr);
433   ierr = MatGetOwnershipRanges(A,&ranges);CHKERRQ(ierr);
434   for (PetscInt i=0; i<size; ++i) {
435     offset[2*i] = ranges[i];
436     offset[2*i+1] = ranges[i+1] - ranges[i];
437   }
438   switch (a->clustering) {
439   case MAT_HTOOL_CLUSTERING_PCA_GEOMETRIC:
440     t = std::make_shared<htool::Cluster<htool::PCA<htool::SplittingTypes::GeometricSplitting>>>(a->dim);
441     break;
442   case MAT_HTOOL_CLUSTERING_BOUNDING_BOX_1_GEOMETRIC:
443     t = std::make_shared<htool::Cluster<htool::BoundingBox1<htool::SplittingTypes::GeometricSplitting>>>(a->dim);
444     break;
445   case MAT_HTOOL_CLUSTERING_BOUNDING_BOX_1_REGULAR:
446     t = std::make_shared<htool::Cluster<htool::BoundingBox1<htool::SplittingTypes::RegularSplitting>>>(a->dim);
447     break;
448   default:
449     t = std::make_shared<htool::Cluster<htool::PCA<htool::SplittingTypes::RegularSplitting>>>(a->dim);
450   }
451   t->set_minclustersize(a->bs[0]);
452   t->build(A->rmap->N,a->gcoords_target,offset);
453   if (a->kernel) a->wrapper = new WrapperHtool(A->rmap->N,A->cmap->N,a->dim,a->kernel,a->kernelctx);
454   else {
455     a->wrapper = NULL;
456     generator = reinterpret_cast<htool::VirtualGenerator<PetscScalar>*>(a->kernelctx);
457   }
458   if (a->gcoords_target != a->gcoords_source) {
459     ierr = MatGetOwnershipRangesColumn(A,&ranges);CHKERRQ(ierr);
460     for (PetscInt i=0; i<size; ++i) {
461       offset[2*i] = ranges[i];
462       offset[2*i+1] = ranges[i+1] - ranges[i];
463     }
464     switch (a->clustering) {
465     case MAT_HTOOL_CLUSTERING_PCA_GEOMETRIC:
466       s = std::make_shared<htool::Cluster<htool::PCA<htool::SplittingTypes::GeometricSplitting>>>(a->dim);
467       break;
468     case MAT_HTOOL_CLUSTERING_BOUNDING_BOX_1_GEOMETRIC:
469       s = std::make_shared<htool::Cluster<htool::BoundingBox1<htool::SplittingTypes::GeometricSplitting>>>(a->dim);
470       break;
471     case MAT_HTOOL_CLUSTERING_BOUNDING_BOX_1_REGULAR:
472       s = std::make_shared<htool::Cluster<htool::BoundingBox1<htool::SplittingTypes::RegularSplitting>>>(a->dim);
473       break;
474     default:
475       s = std::make_shared<htool::Cluster<htool::PCA<htool::SplittingTypes::RegularSplitting>>>(a->dim);
476     }
477     s->set_minclustersize(a->bs[0]);
478     s->build(A->cmap->N,a->gcoords_source,offset);
479     S = uplo = 'N';
480   }
481   ierr = PetscFree(offset);CHKERRQ(ierr);
482   switch (a->compressor) {
483   case MAT_HTOOL_COMPRESSOR_FULL_ACA:
484     compressor = std::make_shared<htool::fullACA<PetscScalar>>();
485     break;
486   case MAT_HTOOL_COMPRESSOR_SVD:
487     compressor = std::make_shared<htool::SVD<PetscScalar>>();
488     break;
489   default:
490     compressor = std::make_shared<htool::sympartialACA<PetscScalar>>();
491   }
492   a->hmatrix = dynamic_cast<htool::VirtualHMatrix<PetscScalar>*>(new htool::HMatrix<PetscScalar>(t,s ? s : t,a->epsilon,a->eta,S,uplo));
493   a->hmatrix->set_compression(compressor);
494   a->hmatrix->set_maxblocksize(a->bs[1]);
495   a->hmatrix->set_mintargetdepth(a->depth[0]);
496   a->hmatrix->set_minsourcedepth(a->depth[1]);
497   if (s) a->hmatrix->build(a->wrapper ? *a->wrapper : *generator,a->gcoords_target,a->gcoords_source);
498   else   a->hmatrix->build(a->wrapper ? *a->wrapper : *generator,a->gcoords_target);
499   PetscFunctionReturn(0);
500 }
501 
502 static PetscErrorCode MatProductNumeric_Htool(Mat C)
503 {
504   Mat_Product       *product = C->product;
505   Mat_Htool         *a = (Mat_Htool*)product->A->data;
506   const PetscScalar *in;
507   PetscScalar       *out;
508   PetscInt          N,lda;
509   PetscErrorCode    ierr;
510 
511   PetscFunctionBegin;
512   MatCheckProduct(C,1);
513   ierr = MatGetSize(C,NULL,&N);CHKERRQ(ierr);
514   ierr = MatDenseGetLDA(C,&lda);CHKERRQ(ierr);
515   PetscCheckFalse(lda != C->rmap->n,PETSC_COMM_SELF,PETSC_ERR_SUP,"Unsupported leading dimension (%" PetscInt_FMT " != %" PetscInt_FMT ")",lda,C->rmap->n);
516   ierr = MatDenseGetArrayRead(product->B,&in);CHKERRQ(ierr);
517   ierr = MatDenseGetArrayWrite(C,&out);CHKERRQ(ierr);
518   switch (product->type) {
519   case MATPRODUCT_AB:
520     a->hmatrix->mvprod_local_to_local(in,out,N);
521     break;
522   case MATPRODUCT_AtB:
523     a->hmatrix->mvprod_transp_local_to_local(in,out,N);
524     break;
525   default:
526     SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"MatProductType %s is not supported",MatProductTypes[product->type]);
527   }
528   ierr = MatDenseRestoreArrayWrite(C,&out);CHKERRQ(ierr);
529   ierr = MatDenseRestoreArrayRead(product->B,&in);CHKERRQ(ierr);
530   ierr = MatScale(C,a->s);CHKERRQ(ierr);
531   PetscFunctionReturn(0);
532 }
533 
534 static PetscErrorCode MatProductSymbolic_Htool(Mat C)
535 {
536   Mat_Product    *product = C->product;
537   Mat            A,B;
538   PetscBool      flg;
539   PetscErrorCode ierr;
540 
541   PetscFunctionBegin;
542   MatCheckProduct(C,1);
543   A = product->A;
544   B = product->B;
545   ierr = PetscObjectTypeCompareAny((PetscObject)B,&flg,MATSEQDENSE,MATMPIDENSE,"");CHKERRQ(ierr);
546   PetscCheckFalse(!flg,PetscObjectComm((PetscObject)B),PETSC_ERR_SUP,"MatProduct_AB not supported for %s",((PetscObject)product->B)->type_name);
547   switch (product->type) {
548   case MATPRODUCT_AB:
549     if (C->rmap->n == PETSC_DECIDE || C->cmap->n == PETSC_DECIDE || C->rmap->N == PETSC_DECIDE || C->cmap->N == PETSC_DECIDE) {
550       ierr = MatSetSizes(C,A->rmap->n,B->cmap->n,A->rmap->N,B->cmap->N);CHKERRQ(ierr);
551     }
552     break;
553   case MATPRODUCT_AtB:
554     if (C->rmap->n == PETSC_DECIDE || C->cmap->n == PETSC_DECIDE || C->rmap->N == PETSC_DECIDE || C->cmap->N == PETSC_DECIDE) {
555       ierr = MatSetSizes(C,A->cmap->n,B->cmap->n,A->cmap->N,B->cmap->N);CHKERRQ(ierr);
556     }
557     break;
558   default:
559     SETERRQ(PetscObjectComm((PetscObject)B),PETSC_ERR_SUP,"ProductType %s is not supported",MatProductTypes[product->type]);
560   }
561   ierr = MatSetType(C,MATDENSE);CHKERRQ(ierr);
562   ierr = MatSetUp(C);CHKERRQ(ierr);
563   ierr = MatSetOption(C,MAT_NO_OFF_PROC_ENTRIES,PETSC_TRUE);CHKERRQ(ierr);
564   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
565   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
566   C->ops->productsymbolic = NULL;
567   C->ops->productnumeric = MatProductNumeric_Htool;
568   PetscFunctionReturn(0);
569 }
570 
571 static PetscErrorCode MatProductSetFromOptions_Htool(Mat C)
572 {
573   PetscFunctionBegin;
574   MatCheckProduct(C,1);
575   if (C->product->type == MATPRODUCT_AB || C->product->type == MATPRODUCT_AtB) C->ops->productsymbolic = MatProductSymbolic_Htool;
576   PetscFunctionReturn(0);
577 }
578 
579 static PetscErrorCode MatHtoolGetHierarchicalMat_Htool(Mat A,const htool::VirtualHMatrix<PetscScalar> **hmatrix)
580 {
581   Mat_Htool *a = (Mat_Htool*)A->data;
582 
583   PetscFunctionBegin;
584   *hmatrix = a->hmatrix;
585   PetscFunctionReturn(0);
586 }
587 
588 /*@C
589      MatHtoolGetHierarchicalMat - Retrieves the opaque pointer to a Htool virtual matrix stored in a MATHTOOL.
590 
591    Input Parameter:
592 .     A - hierarchical matrix
593 
594    Output Parameter:
595 .     hmatrix - opaque pointer to a Htool virtual matrix
596 
597    Level: advanced
598 
599 .seealso:  MATHTOOL
600 @*/
601 PETSC_EXTERN PetscErrorCode MatHtoolGetHierarchicalMat(Mat A,const htool::VirtualHMatrix<PetscScalar> **hmatrix)
602 {
603   PetscErrorCode ierr;
604 
605   PetscFunctionBegin;
606   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
607   PetscValidPointer(hmatrix,2);
608   ierr = PetscTryMethod(A,"MatHtoolGetHierarchicalMat_C",(Mat,const htool::VirtualHMatrix<PetscScalar>**),(A,hmatrix));CHKERRQ(ierr);
609   PetscFunctionReturn(0);
610 }
611 
612 static PetscErrorCode MatHtoolSetKernel_Htool(Mat A,MatHtoolKernel kernel,void *kernelctx)
613 {
614   Mat_Htool *a = (Mat_Htool*)A->data;
615 
616   PetscFunctionBegin;
617   a->kernel    = kernel;
618   a->kernelctx = kernelctx;
619   delete a->wrapper;
620   if (a->kernel) a->wrapper = new WrapperHtool(A->rmap->N,A->cmap->N,a->dim,a->kernel,a->kernelctx);
621   PetscFunctionReturn(0);
622 }
623 
624 /*@C
625      MatHtoolSetKernel - Sets the kernel and context used for the assembly of a MATHTOOL.
626 
627    Input Parameters:
628 +     A - hierarchical matrix
629 .     kernel - computational kernel (or NULL)
630 -     kernelctx - kernel context (if kernel is NULL, the pointer must be of type htool::VirtualGenerator<PetscScalar>*)
631 
632    Level: advanced
633 
634 .seealso:  MATHTOOL, MatCreateHtoolFromKernel()
635 @*/
636 PETSC_EXTERN PetscErrorCode MatHtoolSetKernel(Mat A,MatHtoolKernel kernel,void *kernelctx)
637 {
638   PetscErrorCode ierr;
639 
640   PetscFunctionBegin;
641   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
642   if (!kernelctx) PetscValidFunction(kernel,2);
643   if (!kernel)    PetscValidPointer(kernelctx,3);
644   ierr = PetscTryMethod(A,"MatHtoolSetKernel_C",(Mat,MatHtoolKernel,void*),(A,kernel,kernelctx));CHKERRQ(ierr);
645   PetscFunctionReturn(0);
646 }
647 
648 static PetscErrorCode MatHtoolGetPermutationSource_Htool(Mat A,IS* is)
649 {
650   Mat_Htool             *a = (Mat_Htool*)A->data;
651   std::vector<PetscInt> source;
652   PetscErrorCode        ierr;
653 
654   PetscFunctionBegin;
655   source = a->hmatrix->get_source_cluster()->get_local_perm();
656   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)A),source.size(),source.data(),PETSC_COPY_VALUES,is);CHKERRQ(ierr);
657   ierr = ISSetPermutation(*is);CHKERRQ(ierr);
658   PetscFunctionReturn(0);
659 }
660 
661 /*@C
662      MatHtoolGetPermutationSource - Gets the permutation associated to the source cluster.
663 
664    Input Parameter:
665 .     A - hierarchical matrix
666 
667    Output Parameter:
668 .     is - permutation
669 
670    Level: advanced
671 
672 .seealso:  MATHTOOL, MatHtoolGetPermutationTarget(), MatHtoolUsePermutation()
673 @*/
674 PETSC_EXTERN PetscErrorCode MatHtoolGetPermutationSource(Mat A,IS* is)
675 {
676   PetscErrorCode ierr;
677 
678   PetscFunctionBegin;
679   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
680   if (!is) PetscValidPointer(is,2);
681   ierr = PetscTryMethod(A,"MatHtoolGetPermutationSource_C",(Mat,IS*),(A,is));CHKERRQ(ierr);
682   PetscFunctionReturn(0);
683 }
684 
685 static PetscErrorCode MatHtoolGetPermutationTarget_Htool(Mat A,IS* is)
686 {
687   Mat_Htool             *a = (Mat_Htool*)A->data;
688   std::vector<PetscInt> target;
689   PetscErrorCode        ierr;
690 
691   PetscFunctionBegin;
692   target = a->hmatrix->get_target_cluster()->get_local_perm();
693   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)A),target.size(),target.data(),PETSC_COPY_VALUES,is);CHKERRQ(ierr);
694   ierr = ISSetPermutation(*is);CHKERRQ(ierr);
695   PetscFunctionReturn(0);
696 }
697 
698 /*@C
699      MatHtoolGetPermutationTarget - Gets the permutation associated to the target cluster.
700 
701    Input Parameter:
702 .     A - hierarchical matrix
703 
704    Output Parameter:
705 .     is - permutation
706 
707    Level: advanced
708 
709 .seealso:  MATHTOOL, MatHtoolGetPermutationSource(), MatHtoolUsePermutation()
710 @*/
711 PETSC_EXTERN PetscErrorCode MatHtoolGetPermutationTarget(Mat A,IS* is)
712 {
713   PetscErrorCode ierr;
714 
715   PetscFunctionBegin;
716   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
717   if (!is) PetscValidPointer(is,2);
718   ierr = PetscTryMethod(A,"MatHtoolGetPermutationTarget_C",(Mat,IS*),(A,is));CHKERRQ(ierr);
719   PetscFunctionReturn(0);
720 }
721 
722 static PetscErrorCode MatHtoolUsePermutation_Htool(Mat A,PetscBool use)
723 {
724   Mat_Htool *a = (Mat_Htool*)A->data;
725 
726   PetscFunctionBegin;
727   a->hmatrix->set_use_permutation(use);
728   PetscFunctionReturn(0);
729 }
730 
731 /*@C
732      MatHtoolUsePermutation - Sets whether MATHTOOL should permute input (resp. output) vectors following its internal source (resp. target) permutation.
733 
734    Input Parameters:
735 +     A - hierarchical matrix
736 -     use - Boolean value
737 
738    Level: advanced
739 
740 .seealso:  MATHTOOL, MatHtoolGetPermutationSource(), MatHtoolGetPermutationTarget()
741 @*/
742 PETSC_EXTERN PetscErrorCode MatHtoolUsePermutation(Mat A,PetscBool use)
743 {
744   PetscErrorCode ierr;
745 
746   PetscFunctionBegin;
747   PetscValidHeaderSpecific(A,MAT_CLASSID,1);
748   PetscValidLogicalCollectiveBool(A,use,2);
749   ierr = PetscTryMethod(A,"MatHtoolUsePermutation_C",(Mat,PetscBool),(A,use));CHKERRQ(ierr);
750   PetscFunctionReturn(0);
751 }
752 
753 static PetscErrorCode MatConvert_Htool_Dense(Mat A,MatType newtype,MatReuse reuse,Mat *B)
754 {
755   Mat            C;
756   Mat_Htool      *a = (Mat_Htool*)A->data;
757   PetscInt       lda;
758   PetscScalar    *array;
759   PetscErrorCode ierr;
760 
761   PetscFunctionBegin;
762   if (reuse == MAT_REUSE_MATRIX) {
763     C = *B;
764     PetscCheckFalse(C->rmap->n != A->rmap->n || C->cmap->N != A->cmap->N,PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Incompatible dimensions");
765     ierr = MatDenseGetLDA(C,&lda);CHKERRQ(ierr);
766     PetscCheckFalse(lda != C->rmap->n,PETSC_COMM_SELF,PETSC_ERR_SUP,"Unsupported leading dimension (%" PetscInt_FMT " != %" PetscInt_FMT ")",lda,C->rmap->n);
767   } else {
768     ierr = MatCreate(PetscObjectComm((PetscObject)A),&C);CHKERRQ(ierr);
769     ierr = MatSetSizes(C,A->rmap->n,A->cmap->n,A->rmap->N,A->cmap->N);CHKERRQ(ierr);
770     ierr = MatSetType(C,MATDENSE);CHKERRQ(ierr);
771     ierr = MatSetUp(C);CHKERRQ(ierr);
772     ierr = MatSetOption(C,MAT_NO_OFF_PROC_ENTRIES,PETSC_TRUE);CHKERRQ(ierr);
773   }
774   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
775   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
776   ierr = MatDenseGetArrayWrite(C,&array);CHKERRQ(ierr);
777   a->hmatrix->copy_local_dense_perm(array);
778   ierr = MatDenseRestoreArrayWrite(C,&array);CHKERRQ(ierr);
779   ierr = MatScale(C,a->s);CHKERRQ(ierr);
780   if (reuse == MAT_INPLACE_MATRIX) {
781     ierr = MatHeaderReplace(A,&C);CHKERRQ(ierr);
782   } else *B = C;
783   PetscFunctionReturn(0);
784 }
785 
786 static PetscErrorCode GenEntriesTranspose(PetscInt sdim,PetscInt M,PetscInt N,const PetscInt *rows,const PetscInt *cols,PetscScalar *ptr,void *ctx)
787 {
788   MatHtoolKernelTranspose *generator = (MatHtoolKernelTranspose*)ctx;
789   PetscScalar             *tmp;
790   PetscErrorCode          ierr;
791 
792   PetscFunctionBegin;
793   generator->kernel(sdim,N,M,cols,rows,ptr,generator->kernelctx);
794   ierr = PetscMalloc1(M*N,&tmp);CHKERRQ(ierr);
795   ierr = PetscArraycpy(tmp,ptr,M*N);CHKERRQ(ierr);
796   for (PetscInt i=0; i<M; ++i) {
797     for (PetscInt j=0; j<N; ++j) ptr[i+j*M] = tmp[j+i*N];
798   }
799   ierr = PetscFree(tmp);CHKERRQ(ierr);
800   PetscFunctionReturn(0);
801 }
802 
803 /* naive implementation which keeps a reference to the original Mat */
804 static PetscErrorCode MatTranspose_Htool(Mat A,MatReuse reuse,Mat *B)
805 {
806   Mat                     C;
807   Mat_Htool               *a = (Mat_Htool*)A->data,*c;
808   PetscInt                M = A->rmap->N,N = A->cmap->N,m = A->rmap->n,n = A->cmap->n;
809   PetscContainer          container;
810   MatHtoolKernelTranspose *kernelt;
811   PetscErrorCode          ierr;
812 
813   PetscFunctionBegin;
814   PetscCheckFalse(reuse == MAT_INPLACE_MATRIX,PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"MatTranspose() with MAT_INPLACE_MATRIX not supported");
815   if (reuse == MAT_INITIAL_MATRIX) {
816     ierr = MatCreate(PetscObjectComm((PetscObject)A),&C);CHKERRQ(ierr);
817     ierr = MatSetSizes(C,n,m,N,M);CHKERRQ(ierr);
818     ierr = MatSetType(C,((PetscObject)A)->type_name);CHKERRQ(ierr);
819     ierr = MatSetUp(C);CHKERRQ(ierr);
820     ierr = PetscContainerCreate(PetscObjectComm((PetscObject)C),&container);CHKERRQ(ierr);
821     ierr = PetscNew(&kernelt);CHKERRQ(ierr);
822     ierr = PetscContainerSetPointer(container,kernelt);CHKERRQ(ierr);
823     ierr = PetscObjectCompose((PetscObject)C,"KernelTranspose",(PetscObject)container);CHKERRQ(ierr);
824   } else {
825     C = *B;
826     ierr = PetscObjectQuery((PetscObject)C,"KernelTranspose",(PetscObject*)&container);CHKERRQ(ierr);
827     PetscCheckFalse(!container,PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call MatTranspose() with MAT_INITIAL_MATRIX first");
828     ierr = PetscContainerGetPointer(container,(void**)&kernelt);CHKERRQ(ierr);
829   }
830   c                  = (Mat_Htool*)C->data;
831   c->dim             = a->dim;
832   c->s               = a->s;
833   c->kernel          = GenEntriesTranspose;
834   if (kernelt->A != A) {
835     ierr = MatDestroy(&kernelt->A);CHKERRQ(ierr);
836     kernelt->A       = A;
837     ierr = PetscObjectReference((PetscObject)A);CHKERRQ(ierr);
838   }
839   kernelt->kernel    = a->kernel;
840   kernelt->kernelctx = a->kernelctx;
841   c->kernelctx       = kernelt;
842   if (reuse == MAT_INITIAL_MATRIX) {
843     ierr = PetscMalloc1(N*c->dim,&c->gcoords_target);CHKERRQ(ierr);
844     ierr = PetscArraycpy(c->gcoords_target,a->gcoords_source,N*c->dim);CHKERRQ(ierr);
845     if (a->gcoords_target != a->gcoords_source) {
846       ierr = PetscMalloc1(M*c->dim,&c->gcoords_source);CHKERRQ(ierr);
847       ierr = PetscArraycpy(c->gcoords_source,a->gcoords_target,M*c->dim);CHKERRQ(ierr);
848     } else c->gcoords_source = c->gcoords_target;
849     ierr = PetscCalloc2(M,&c->work_source,N,&c->work_target);CHKERRQ(ierr);
850   }
851   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
852   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
853   if (reuse == MAT_INITIAL_MATRIX) *B = C;
854   PetscFunctionReturn(0);
855 }
856 
857 /*@C
858      MatCreateHtoolFromKernel - Creates a MATHTOOL from a user-supplied kernel.
859 
860    Input Parameters:
861 +     comm - MPI communicator
862 .     m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
863 .     n - number of local columns (or PETSC_DECIDE to have calculated if N is given)
864 .     M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
865 .     N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
866 .     spacedim - dimension of the space coordinates
867 .     coords_target - coordinates of the target
868 .     coords_source - coordinates of the source
869 .     kernel - computational kernel (or NULL)
870 -     kernelctx - kernel context (if kernel is NULL, the pointer must be of type htool::VirtualGenerator<PetscScalar>*)
871 
872    Output Parameter:
873 .     B - matrix
874 
875    Options Database Keys:
876 +     -mat_htool_min_cluster_size <PetscInt> - minimal leaf size in cluster tree
877 .     -mat_htool_max_block_size <PetscInt> - maximal number of coefficients in a dense block
878 .     -mat_htool_epsilon <PetscReal> - relative error in Frobenius norm when approximating a block
879 .     -mat_htool_eta <PetscReal> - admissibility condition tolerance
880 .     -mat_htool_min_target_depth <PetscInt> - minimal cluster tree depth associated with the rows
881 .     -mat_htool_min_source_depth <PetscInt> - minimal cluster tree depth associated with the columns
882 .     -mat_htool_compressor <sympartialACA, fullACA, SVD> - type of compression
883 -     -mat_htool_clustering <PCARegular, PCAGeometric, BounbingBox1Regular, BoundingBox1Geometric> - type of clustering
884 
885    Level: intermediate
886 
887 .seealso:  MatCreate(), MATHTOOL, PCSetCoordinates(), MatHtoolSetKernel(), MatHtoolCompressorType, MATH2OPUS, MatCreateH2OpusFromKernel()
888 @*/
889 PetscErrorCode MatCreateHtoolFromKernel(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,PetscInt spacedim,const PetscReal coords_target[],const PetscReal coords_source[],MatHtoolKernel kernel,void *kernelctx,Mat *B)
890 {
891   Mat            A;
892   Mat_Htool      *a;
893   PetscErrorCode ierr;
894 
895   PetscFunctionBegin;
896   ierr = MatCreate(comm,&A);CHKERRQ(ierr);
897   PetscValidLogicalCollectiveInt(A,spacedim,6);
898   PetscValidRealPointer(coords_target,7);
899   PetscValidRealPointer(coords_source,8);
900   if (!kernelctx) PetscValidFunction(kernel,9);
901   if (!kernel)    PetscValidPointer(kernelctx,10);
902   ierr = MatSetSizes(A,m,n,M,N);CHKERRQ(ierr);
903   ierr = MatSetType(A,MATHTOOL);CHKERRQ(ierr);
904   ierr = MatSetUp(A);CHKERRQ(ierr);
905   a            = (Mat_Htool*)A->data;
906   a->dim       = spacedim;
907   a->s         = 1.0;
908   a->kernel    = kernel;
909   a->kernelctx = kernelctx;
910   ierr = PetscCalloc1(A->rmap->N*spacedim,&a->gcoords_target);CHKERRQ(ierr);
911   ierr = PetscArraycpy(a->gcoords_target+A->rmap->rstart*spacedim,coords_target,A->rmap->n*spacedim);CHKERRQ(ierr);
912   ierr = MPIU_Allreduce(MPI_IN_PLACE,a->gcoords_target,A->rmap->N*spacedim,MPIU_REAL,MPI_SUM,PetscObjectComm((PetscObject)A));CHKERRMPI(ierr); /* global target coordinates */
913   if (coords_target != coords_source) {
914     ierr = PetscCalloc1(A->cmap->N*spacedim,&a->gcoords_source);CHKERRQ(ierr);
915     ierr = PetscArraycpy(a->gcoords_source+A->cmap->rstart*spacedim,coords_source,A->cmap->n*spacedim);CHKERRQ(ierr);
916     ierr = MPIU_Allreduce(MPI_IN_PLACE,a->gcoords_source,A->cmap->N*spacedim,MPIU_REAL,MPI_SUM,PetscObjectComm((PetscObject)A));CHKERRMPI(ierr); /* global source coordinates */
917   } else a->gcoords_source = a->gcoords_target;
918   ierr = PetscCalloc2(A->cmap->N,&a->work_source,A->rmap->N,&a->work_target);CHKERRQ(ierr);
919   *B = A;
920   PetscFunctionReturn(0);
921 }
922 
923 /*MC
924      MATHTOOL = "htool" - A matrix type for hierarchical matrices using the Htool package.
925 
926   Use ./configure --download-htool to install PETSc to use Htool.
927 
928    Options Database Keys:
929 .     -mat_type htool - matrix type to "htool" during a call to MatSetFromOptions()
930 
931    Level: beginner
932 
933 .seealso: MATH2OPUS, MATDENSE, MatCreateHtoolFromKernel(), MatHtoolSetKernel()
934 M*/
935 PETSC_EXTERN PetscErrorCode MatCreate_Htool(Mat A)
936 {
937   Mat_Htool      *a;
938   PetscErrorCode ierr;
939 
940   PetscFunctionBegin;
941   ierr = PetscNewLog(A,&a);CHKERRQ(ierr);
942   A->data = (void*)a;
943   ierr = PetscObjectChangeTypeName((PetscObject)A,MATHTOOL);CHKERRQ(ierr);
944   ierr = PetscMemzero(A->ops,sizeof(struct _MatOps));CHKERRQ(ierr);
945   A->ops->getdiagonal       = MatGetDiagonal_Htool;
946   A->ops->getdiagonalblock  = MatGetDiagonalBlock_Htool;
947   A->ops->mult              = MatMult_Htool;
948   A->ops->multadd           = MatMultAdd_Htool;
949   A->ops->multtranspose     = MatMultTranspose_Htool;
950   if (!PetscDefined(USE_COMPLEX)) A->ops->multhermitiantranspose = MatMultTranspose_Htool;
951   A->ops->increaseoverlap   = MatIncreaseOverlap_Htool;
952   A->ops->createsubmatrices = MatCreateSubMatrices_Htool;
953   A->ops->transpose         = MatTranspose_Htool;
954   A->ops->destroy           = MatDestroy_Htool;
955   A->ops->view              = MatView_Htool;
956   A->ops->setfromoptions    = MatSetFromOptions_Htool;
957   A->ops->scale             = MatScale_Htool;
958   A->ops->getrow            = MatGetRow_Htool;
959   A->ops->restorerow        = MatRestoreRow_Htool;
960   A->ops->assemblyend       = MatAssemblyEnd_Htool;
961   a->dim                    = 0;
962   a->gcoords_target         = NULL;
963   a->gcoords_source         = NULL;
964   a->s                      = 1.0;
965   a->bs[0]                  = 10;
966   a->bs[1]                  = 1000000;
967   a->epsilon                = PetscSqrtReal(PETSC_SMALL);
968   a->eta                    = 10.0;
969   a->depth[0]               = 0;
970   a->depth[1]               = 0;
971   a->compressor             = MAT_HTOOL_COMPRESSOR_SYMPARTIAL_ACA;
972   ierr = PetscObjectComposeFunction((PetscObject)A,"MatProductSetFromOptions_htool_seqdense_C",MatProductSetFromOptions_Htool);CHKERRQ(ierr);
973   ierr = PetscObjectComposeFunction((PetscObject)A,"MatProductSetFromOptions_htool_mpidense_C",MatProductSetFromOptions_Htool);CHKERRQ(ierr);
974   ierr = PetscObjectComposeFunction((PetscObject)A,"MatConvert_htool_seqdense_C",MatConvert_Htool_Dense);CHKERRQ(ierr);
975   ierr = PetscObjectComposeFunction((PetscObject)A,"MatConvert_htool_mpidense_C",MatConvert_Htool_Dense);CHKERRQ(ierr);
976   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolGetHierarchicalMat_C",MatHtoolGetHierarchicalMat_Htool);CHKERRQ(ierr);
977   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolSetKernel_C",MatHtoolSetKernel_Htool);CHKERRQ(ierr);
978   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolGetPermutationSource_C",MatHtoolGetPermutationSource_Htool);CHKERRQ(ierr);
979   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolGetPermutationTarget_C",MatHtoolGetPermutationTarget_Htool);CHKERRQ(ierr);
980   ierr = PetscObjectComposeFunction((PetscObject)A,"MatHtoolUsePermutation_C",MatHtoolUsePermutation_Htool);CHKERRQ(ierr);
981   PetscFunctionReturn(0);
982 }
983