Actual source code: sorder.c
petsc-3.14.6 2021-03-30
2: /*
3: Provides the code that allows PETSc users to register their own
4: sequential matrix Ordering routines.
5: */
6: #include <petsc/private/matimpl.h>
7: #include <petscmat.h>
9: PetscFunctionList MatOrderingList = NULL;
10: PetscBool MatOrderingRegisterAllCalled = PETSC_FALSE;
12: extern PetscErrorCode MatGetOrdering_Flow_SeqAIJ(Mat,MatOrderingType,IS*,IS*);
14: PetscErrorCode MatGetOrdering_Flow(Mat mat,MatOrderingType type,IS *irow,IS *icol)
15: {
17: SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"Cannot do default flow ordering for matrix type");
18: }
20: PETSC_INTERN PetscErrorCode MatGetOrdering_Natural(Mat mat,MatOrderingType type,IS *irow,IS *icol)
21: {
23: PetscInt n,i,*ii;
24: PetscBool done;
25: MPI_Comm comm;
28: PetscObjectGetComm((PetscObject)mat,&comm);
29: MatGetRowIJ(mat,0,PETSC_FALSE,PETSC_TRUE,&n,NULL,NULL,&done);
30: MatRestoreRowIJ(mat,0,PETSC_FALSE,PETSC_TRUE,NULL,NULL,NULL,&done);
31: if (done) { /* matrix may be "compressed" in symbolic factorization, due to i-nodes or block storage */
32: /*
33: We actually create general index sets because this avoids mallocs to
34: to obtain the indices in the MatSolve() routines.
35: ISCreateStride(PETSC_COMM_SELF,n,0,1,irow);
36: ISCreateStride(PETSC_COMM_SELF,n,0,1,icol);
37: */
38: PetscMalloc1(n,&ii);
39: for (i=0; i<n; i++) ii[i] = i;
40: ISCreateGeneral(PETSC_COMM_SELF,n,ii,PETSC_COPY_VALUES,irow);
41: ISCreateGeneral(PETSC_COMM_SELF,n,ii,PETSC_OWN_POINTER,icol);
42: } else {
43: PetscInt start,end;
45: MatGetOwnershipRange(mat,&start,&end);
46: ISCreateStride(comm,end-start,start,1,irow);
47: ISCreateStride(comm,end-start,start,1,icol);
48: }
49: ISSetIdentity(*irow);
50: ISSetIdentity(*icol);
51: return(0);
52: }
54: /*
55: Orders the rows (and columns) by the lengths of the rows.
56: This produces a symmetric Ordering but does not require a
57: matrix with symmetric non-zero structure.
58: */
59: PETSC_INTERN PetscErrorCode MatGetOrdering_RowLength(Mat mat,MatOrderingType type,IS *irow,IS *icol)
60: {
62: PetscInt n,*permr,*lens,i;
63: const PetscInt *ia,*ja;
64: PetscBool done;
67: MatGetRowIJ(mat,0,PETSC_FALSE,PETSC_TRUE,&n,&ia,&ja,&done);
68: if (!done) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"Cannot get rows for matrix");
70: PetscMalloc2(n,&lens,n,&permr);
71: for (i=0; i<n; i++) {
72: lens[i] = ia[i+1] - ia[i];
73: permr[i] = i;
74: }
75: MatRestoreRowIJ(mat,0,PETSC_FALSE,PETSC_TRUE,NULL,&ia,&ja,&done);
77: PetscSortIntWithPermutation(n,lens,permr);
79: ISCreateGeneral(PETSC_COMM_SELF,n,permr,PETSC_COPY_VALUES,irow);
80: ISCreateGeneral(PETSC_COMM_SELF,n,permr,PETSC_COPY_VALUES,icol);
81: PetscFree2(lens,permr);
82: return(0);
83: }
85: /*@C
86: MatOrderingRegister - Adds a new sparse matrix ordering to the matrix package.
88: Not Collective
90: Input Parameters:
91: + sname - name of ordering (for example MATORDERINGND)
92: - function - function pointer that creates the ordering
94: Level: developer
96: Sample usage:
97: .vb
98: MatOrderingRegister("my_order", MyOrder);
99: .ve
101: Then, your partitioner can be chosen with the procedural interface via
102: $ MatOrderingSetType(part,"my_order)
103: or at runtime via the option
104: $ -pc_factor_mat_ordering_type my_order
106: .seealso: MatOrderingRegisterDestroy(), MatOrderingRegisterAll()
107: @*/
108: PetscErrorCode MatOrderingRegister(const char sname[],PetscErrorCode (*function)(Mat,MatOrderingType,IS*,IS*))
109: {
113: MatInitializePackage();
114: PetscFunctionListAdd(&MatOrderingList,sname,function);
115: return(0);
116: }
118: #include <../src/mat/impls/aij/mpi/mpiaij.h>
119: /*@C
120: MatGetOrdering - Gets a reordering for a matrix to reduce fill or to
121: improve numerical stability of LU factorization.
123: Collective on Mat
125: Input Parameters:
126: + mat - the matrix
127: - type - type of reordering, one of the following:
128: $ MATORDERINGNATURAL_OR_ND - Nested dissection unless matrix is SBAIJ then it is natural
129: $ MATORDERINGNATURAL - Natural
130: $ MATORDERINGND - Nested Dissection
131: $ MATORDERING1WD - One-way Dissection
132: $ MATORDERINGRCM - Reverse Cuthill-McKee
133: $ MATORDERINGQMD - Quotient Minimum Degree
134: $ MATORDERINGEXTERNAL - Use an ordering internal to the factorzation package and do not compute or use PETSc's
136: Output Parameters:
137: + rperm - row permutation indices
138: - cperm - column permutation indices
140: Options Database Key:
141: + -mat_view_ordering draw - plots matrix nonzero structure in new ordering
142: - -pc_factor_mat_ordering_type <nd,natural,..> - ordering to use with PCs based on factorization, LU, ILU, Cholesky, ICC
144: Level: intermediate
146: Notes:
147: This DOES NOT actually reorder the matrix; it merely returns two index sets
148: that define a reordering. This is usually not used directly, rather use the
149: options PCFactorSetMatOrderingType()
151: The user can define additional orderings; see MatOrderingRegister().
153: These are generally only implemented for sequential sparse matrices.
155: Some external packages that PETSc can use for direct factorization such as SuperLU do not accept orderings provided by
156: this call.
158: If MATORDERINGEXTERNAL is used then PETSc does not compute an ordering and utilizes one built into the factorization package
160: fill, reordering, natural, Nested Dissection,
161: One-way Dissection, Cholesky, Reverse Cuthill-McKee,
162: Quotient Minimum Degree
164: .seealso: MatOrderingRegister(), PCFactorSetMatOrderingType(), MatColoring, MatColoringCreate()
165: @*/
166: PetscErrorCode MatGetOrdering(Mat mat,MatOrderingType type,IS *rperm,IS *cperm)
167: {
169: PetscInt mmat,nmat,mis,m;
170: PetscErrorCode (*r)(Mat,MatOrderingType,IS*,IS*);
171: PetscBool flg = PETSC_FALSE,isseqdense,ismpidense,ismpiaij,ismpibaij,ismpisbaij,ismpiaijcusparse,iselemental,isscalapack,flg1;
177: if (!mat->assembled) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Not for unassembled matrix");
178: if (mat->factortype) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
180: PetscStrcmp(type,MATORDERINGEXTERNAL,&flg1);
181: if (flg1) {
182: *rperm = NULL;
183: *cperm = NULL;
184: return(0);
185: }
187: PetscStrcmp(type,MATORDERINGNATURAL_OR_ND,&flg1);
188: if (flg1) {
189: PetscBool isseqsbaij;
190: PetscObjectTypeCompareAny((PetscObject)mat,&isseqsbaij,MATSEQSBAIJ,MATSEQBAIJ,NULL);
191: if (isseqsbaij) {
192: type = MATORDERINGNATURAL;
193: } else {
194: type = MATORDERINGND;
195: }
196: }
198: /* This code is terrible. MatGetOrdering() multiple dispatch should use matrix and this code should move to impls/aij/mpi. */
199: PetscObjectTypeCompare((PetscObject)mat,MATMPIAIJ,&ismpiaij);
200: if (ismpiaij) { /* Reorder using diagonal block */
201: Mat Ad,Ao;
202: const PetscInt *colmap;
203: IS lrowperm,lcolperm;
204: PetscInt i,rstart,rend,*idx;
205: const PetscInt *lidx;
207: MatMPIAIJGetSeqAIJ(mat,&Ad,&Ao,&colmap);
208: MatGetOrdering(Ad,type,&lrowperm,&lcolperm);
209: MatGetOwnershipRange(mat,&rstart,&rend);
210: /* Remap row index set to global space */
211: ISGetIndices(lrowperm,&lidx);
212: PetscMalloc1(rend-rstart,&idx);
213: for (i=0; i+rstart<rend; i++) idx[i] = rstart + lidx[i];
214: ISRestoreIndices(lrowperm,&lidx);
215: ISDestroy(&lrowperm);
216: ISCreateGeneral(PetscObjectComm((PetscObject)mat),rend-rstart,idx,PETSC_OWN_POINTER,rperm);
217: ISSetPermutation(*rperm);
218: /* Remap column index set to global space */
219: ISGetIndices(lcolperm,&lidx);
220: PetscMalloc1(rend-rstart,&idx);
221: for (i=0; i+rstart<rend; i++) idx[i] = rstart + lidx[i];
222: ISRestoreIndices(lcolperm,&lidx);
223: ISDestroy(&lcolperm);
224: ISCreateGeneral(PetscObjectComm((PetscObject)mat),rend-rstart,idx,PETSC_OWN_POINTER,cperm);
225: ISSetPermutation(*cperm);
226: return(0);
227: }
229: /* this chunk of code is REALLY bad, should maybe get the ordering from the factor matrix,
230: then those that don't support orderings will handle their cases themselves. */
231: PetscObjectTypeCompare((PetscObject)mat,MATSEQDENSE,&isseqdense);
232: PetscObjectTypeCompare((PetscObject)mat,MATMPIDENSE,&ismpidense);
233: PetscObjectTypeCompare((PetscObject)mat,MATMPIAIJCUSPARSE,&ismpiaijcusparse);
234: PetscObjectTypeCompare((PetscObject)mat,MATMPIBAIJ,&ismpibaij);
235: PetscObjectTypeCompare((PetscObject)mat,MATMPISBAIJ,&ismpisbaij);
236: PetscObjectTypeCompare((PetscObject)mat,MATELEMENTAL,&iselemental);
237: PetscObjectTypeCompare((PetscObject)mat,MATSCALAPACK,&isscalapack);
238: if (isseqdense || ismpidense || ismpibaij || ismpisbaij || ismpiaijcusparse || iselemental || isscalapack) {
239: MatGetLocalSize(mat,&m,NULL);
240: /*
241: These matrices only give natural ordering
242: */
243: ISCreateStride(PETSC_COMM_SELF,m,0,1,cperm);
244: ISCreateStride(PETSC_COMM_SELF,m,0,1,rperm);
245: ISSetIdentity(*cperm);
246: ISSetIdentity(*rperm);
247: return(0);
248: }
250: if (!mat->rmap->N) { /* matrix has zero rows */
251: ISCreateStride(PETSC_COMM_SELF,0,0,1,cperm);
252: ISCreateStride(PETSC_COMM_SELF,0,0,1,rperm);
253: ISSetIdentity(*cperm);
254: ISSetIdentity(*rperm);
255: return(0);
256: }
258: MatGetLocalSize(mat,&mmat,&nmat);
259: if (mmat != nmat) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Must be square matrix, rows %D columns %D",mmat,nmat);
261: MatOrderingRegisterAll();
262: PetscFunctionListFind(MatOrderingList,type,&r);
263: if (!r) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Unknown or unregistered type: %s",type);
265: PetscLogEventBegin(MAT_GetOrdering,mat,0,0,0);
266: (*r)(mat,type,rperm,cperm);
267: ISSetPermutation(*rperm);
268: ISSetPermutation(*cperm);
269: /* Adjust for inode (reduced matrix ordering) only if row permutation is smaller the matrix size */
270: ISGetLocalSize(*rperm,&mis);
271: if (mmat > mis) {MatInodeAdjustForInodes(mat,rperm,cperm);}
272: PetscLogEventEnd(MAT_GetOrdering,mat,0,0,0);
275: PetscOptionsHasName(((PetscObject)mat)->options,((PetscObject)mat)->prefix,"-mat_view_ordering",&flg);
276: if (flg) {
277: Mat tmat;
278: MatPermute(mat,*rperm,*cperm,&tmat);
279: MatViewFromOptions(tmat,(PetscObject)mat,"-mat_view_ordering");
280: MatDestroy(&tmat);
281: }
282: return(0);
283: }
285: PetscErrorCode MatGetOrderingList(PetscFunctionList *list)
286: {
288: *list = MatOrderingList;
289: return(0);
290: }