xref: /petsc/src/dm/impls/plex/plexreorder.c (revision 83808cfd609ad7d37dbcaec8da42a6dcda439589)
1 #include <petsc-private/dmpleximpl.h>   /*I      "petscdmplex.h"   I*/
2 #include <petsc-private/matorderimpl.h> /*I      "petscmat.h"      I*/
3 
4 #undef __FUNCT__
5 #define __FUNCT__ "DMPlexCreateOrderingClosure_Static"
6 PetscErrorCode DMPlexCreateOrderingClosure_Static(DM dm, PetscInt numPoints, const PetscInt pperm[], PetscInt **clperm, PetscInt **invclperm)
7 {
8   PetscInt      *perm, *iperm;
9   PetscInt       depth, d, pStart, pEnd, fStart, fMax, fEnd, p;
10   PetscErrorCode ierr;
11 
12   PetscFunctionBegin;
13   ierr = DMPlexGetDepth(dm, &depth);CHKERRQ(ierr);
14   ierr = DMPlexGetChart(dm, &pStart, &pEnd);CHKERRQ(ierr);
15   ierr = PetscMalloc2(pEnd-pStart,PetscInt,&perm,pEnd-pStart,PetscInt,&iperm);CHKERRQ(ierr);
16   for (p = pStart; p < pEnd; ++p) iperm[p] = -1;
17   for (d = depth; d > 0; --d) {
18     ierr = DMPlexGetDepthStratum(dm, d,   &pStart, &pEnd);CHKERRQ(ierr);
19     ierr = DMPlexGetDepthStratum(dm, d-1, &fStart, &fEnd);CHKERRQ(ierr);
20     fMax = fStart;
21     for (p = pStart; p < pEnd; ++p) {
22       const PetscInt *cone;
23       PetscInt        point, coneSize, c;
24 
25       if (d == depth) {
26         perm[p]         = pperm[p];
27         iperm[pperm[p]] = p;
28       }
29       point = perm[p];
30       ierr = DMPlexGetConeSize(dm, point, &coneSize);CHKERRQ(ierr);
31       ierr = DMPlexGetCone(dm, point, &cone);CHKERRQ(ierr);
32       for (c = 0; c < coneSize; ++c) {
33         const PetscInt oldc = cone[c];
34         const PetscInt newc = iperm[oldc];
35 
36         if (newc < 0) {
37           perm[fMax]  = oldc;
38           iperm[oldc] = fMax++;
39         }
40       }
41     }
42     if (fMax != fEnd) SETERRQ3(PETSC_COMM_SELF, PETSC_ERR_PLIB, "Number of depth %d faces %d does not match permuted nubmer %d", d, fEnd-fStart, fMax-fStart);
43   }
44   *clperm    = perm;
45   *invclperm = iperm;
46   PetscFunctionReturn(0);
47 }
48 
49 #undef __FUNCT__
50 #define __FUNCT__ "DMPlexGetOrdering"
51 /*@
52   DMPlexGetOrdering - Calculate a reordering of the mesh
53 
54   Collective on DM
55 
56   Input Parameter:
57 + dm - The DMPlex object
58 - otype - type of reordering, one of the following:
59 $     MATORDERINGNATURAL - Natural
60 $     MATORDERINGND - Nested Dissection
61 $     MATORDERING1WD - One-way Dissection
62 $     MATORDERINGRCM - Reverse Cuthill-McKee
63 $     MATORDERINGQMD - Quotient Minimum Degree
64 
65 
66   Output Parameter:
67 . perm - The point permutation as an IS
68 
69   Level: intermediate
70 
71 .keywords: mesh
72 .seealso: MatGetOrdering()
73 @*/
74 PetscErrorCode DMPlexGetOrdering(DM dm, MatOrderingType otype, IS *perm)
75 {
76   PetscInt       numCells = 0;
77   PetscInt      *start = NULL, *adjacency = NULL, *cperm, *clperm, *invclperm, *mask, *xls, pStart, pEnd, c, i;
78   PetscErrorCode ierr;
79 
80   PetscFunctionBegin;
81   PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
82   PetscValidPointer(perm, 3);
83   ierr = DMPlexCreateNeighborCSR(dm, 0, &numCells, &start, &adjacency);CHKERRQ(ierr);
84   ierr = PetscMalloc3(numCells,PetscInt,&cperm,numCells,PetscInt,&mask,numCells*2,PetscInt,&xls);CHKERRQ(ierr);
85   /* Shift for Fortran numbering */
86   for (i = 0; i < start[numCells]; ++i) ++adjacency[i];
87   for (i = 0; i <= numCells; ++i)       ++start[i];
88   ierr = SPARSEPACKgenrcm(&numCells, start, adjacency, cperm, mask, xls);CHKERRQ(ierr);
89   ierr = PetscFree(start);CHKERRQ(ierr);
90   ierr = PetscFree(adjacency);CHKERRQ(ierr);
91   /* Shift for Fortran numbering */
92   for (c = 0; c < numCells; ++c) --cperm[c];
93   /* Construct closure */
94   ierr = DMPlexCreateOrderingClosure_Static(dm, numCells, cperm, &clperm, &invclperm);
95   ierr = PetscFree3(cperm,mask,xls);CHKERRQ(ierr);
96   ierr = PetscFree(clperm);CHKERRQ(ierr);
97   /* Invert permutation */
98   ierr = DMPlexGetChart(dm, &pStart, &pEnd);CHKERRQ(ierr);
99   ierr = ISCreateGeneral(PetscObjectComm((PetscObject) dm), pEnd-pStart, invclperm, PETSC_OWN_POINTER, perm);CHKERRQ(ierr);
100   PetscFunctionReturn(0);
101 }
102 
103 #undef __FUNCT__
104 #define __FUNCT__ "DMPlexPermute"
105 /*@
106   DMPlexPermute - Reorder the mesh according to the input permutation
107 
108   Collective on DM
109 
110   Input Parameter:
111 + dm - The DMPlex object
112 - perm - The point permutation
113 
114   Output Parameter:
115 . pdm - The permuted DM
116 
117   Level: intermediate
118 
119 .keywords: mesh
120 .seealso: MatPermute()
121 @*/
122 PetscErrorCode DMPlexPermute(DM dm, IS perm, DM *pdm)
123 {
124   DM_Plex       *plex = (DM_Plex *) dm->data, *plexNew;
125   PetscSection   section, sectionNew;
126   PetscInt       dim;
127   PetscErrorCode ierr;
128 
129   PetscFunctionBegin;
130   PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
131   PetscValidHeaderSpecific(perm, IS_CLASSID, 2);
132   PetscValidPointer(pdm, 3);
133   ierr = DMCreate(PetscObjectComm((PetscObject) dm), pdm);CHKERRQ(ierr);
134   ierr = DMSetType(*pdm, DMPLEX);CHKERRQ(ierr);
135   ierr = DMPlexGetDimension(dm, &dim);CHKERRQ(ierr);
136   ierr = DMPlexSetDimension(*pdm, dim);CHKERRQ(ierr);
137   ierr = DMGetDefaultSection(dm, &section);CHKERRQ(ierr);
138   if (section) {
139     ierr = PetscSectionPermute(section, perm, &sectionNew);CHKERRQ(ierr);
140     ierr = DMSetDefaultSection(*pdm, sectionNew);CHKERRQ(ierr);
141     ierr = PetscSectionDestroy(&sectionNew);CHKERRQ(ierr);
142   }
143   plexNew = (DM_Plex *) (*pdm)->data;
144   /* Ignore ltogmap, ltogmapb */
145   /* Ignore sf, defaultSF */
146   /* Ignore globalVertexNumbers, globalCellNumbers */
147   /* Remap coordinates */
148   {
149     DM           cdm, cdmNew;
150     PetscSection csection, csectionNew;
151     Vec          coordinates, coordinatesNew;
152     PetscScalar *coords, *coordsNew;
153     PetscInt     pStart, pEnd, p;
154 
155     ierr = DMGetCoordinateDM(dm, &cdm);CHKERRQ(ierr);
156     ierr = DMGetDefaultSection(cdm, &csection);CHKERRQ(ierr);
157     ierr = PetscSectionPermute(csection, perm, &csectionNew);CHKERRQ(ierr);
158     ierr = DMGetCoordinatesLocal(dm, &coordinates);CHKERRQ(ierr);
159     ierr = VecDuplicate(coordinates, &coordinatesNew);CHKERRQ(ierr);
160     ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
161     ierr = VecGetArray(coordinatesNew, &coordsNew);CHKERRQ(ierr);
162     ierr = PetscSectionGetChart(csectionNew, &pStart, &pEnd);CHKERRQ(ierr);
163     for (p = pStart; p < pEnd; ++p) {
164       PetscInt dof, off, offNew, d;
165 
166       ierr = PetscSectionGetDof(csectionNew, p, &dof);CHKERRQ(ierr);
167       ierr = PetscSectionGetOffset(csection, p, &off);CHKERRQ(ierr);
168       ierr = PetscSectionGetOffset(csectionNew, p, &offNew);CHKERRQ(ierr);
169       for (d = 0; d < dof; ++d) coordsNew[offNew+d] = coords[off+d];
170     }
171     ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
172     ierr = VecRestoreArray(coordinatesNew, &coordsNew);CHKERRQ(ierr);
173     ierr = DMGetCoordinateDM(*pdm, &cdmNew);CHKERRQ(ierr);
174     ierr = DMSetDefaultSection(cdmNew, csectionNew);CHKERRQ(ierr);
175     ierr = DMSetCoordinatesLocal(*pdm, coordinatesNew);CHKERRQ(ierr);
176     ierr = PetscSectionDestroy(&csectionNew);CHKERRQ(ierr);
177     ierr = VecDestroy(&coordinatesNew);CHKERRQ(ierr);
178   }
179   /* Reorder labels */
180   {
181     DMLabel label = plex->labels, labelNew = NULL;
182 
183     while (label) {
184       if (!plexNew->labels) {
185         ierr = DMLabelPermute(label, perm, &plexNew->labels);CHKERRQ(ierr);
186         labelNew = plexNew->labels;
187       } else {
188         ierr = DMLabelPermute(label, perm, &labelNew->next);CHKERRQ(ierr);
189         labelNew = labelNew->next;
190       }
191       label = label->next;
192     }
193     if (plex->subpointMap) {ierr = DMLabelPermute(plex->subpointMap, perm, &plexNew->subpointMap);CHKERRQ(ierr);}
194   }
195   /* Reorder topology */
196   {
197     const PetscInt *pperm;
198     PetscInt        maxConeSize, maxSupportSize, n, pStart, pEnd, p;
199 
200     ierr = DMPlexGetMaxSizes(dm, &maxConeSize, &maxSupportSize);CHKERRQ(ierr);
201     plexNew->maxConeSize    = maxConeSize;
202     plexNew->maxSupportSize = maxSupportSize;
203     ierr = PetscSectionDestroy(&plexNew->coneSection);CHKERRQ(ierr);
204     ierr = PetscSectionPermute(plex->coneSection, perm, &plexNew->coneSection);CHKERRQ(ierr);
205     ierr = PetscSectionGetStorageSize(plexNew->coneSection, &n);CHKERRQ(ierr);
206     ierr = PetscMalloc(n * sizeof(PetscInt), &plexNew->cones);CHKERRQ(ierr);
207     ierr = PetscMalloc(n * sizeof(PetscInt), &plexNew->coneOrientations);CHKERRQ(ierr);
208     ierr = ISGetIndices(perm, &pperm);CHKERRQ(ierr);
209     ierr = PetscSectionGetChart(plex->coneSection, &pStart, &pEnd);CHKERRQ(ierr);
210     for (p = pStart; p < pEnd; ++p) {
211       PetscInt dof, off, offNew, d;
212 
213       ierr = PetscSectionGetDof(plexNew->coneSection, pperm[p], &dof);CHKERRQ(ierr);
214       ierr = PetscSectionGetOffset(plex->coneSection, p, &off);CHKERRQ(ierr);
215       ierr = PetscSectionGetOffset(plexNew->coneSection, pperm[p], &offNew);CHKERRQ(ierr);
216       for (d = 0; d < dof; ++d) {
217         plexNew->cones[offNew+d]            = pperm[plex->cones[off+d]];
218         plexNew->coneOrientations[offNew+d] = plex->coneOrientations[off+d];
219       }
220     }
221     ierr = PetscSectionDestroy(&plexNew->supportSection);CHKERRQ(ierr);
222     ierr = PetscSectionPermute(plex->supportSection, perm, &plexNew->supportSection);CHKERRQ(ierr);
223     ierr = PetscSectionGetStorageSize(plexNew->supportSection, &n);CHKERRQ(ierr);
224     ierr = PetscMalloc(n * sizeof(PetscInt), &plexNew->supports);CHKERRQ(ierr);
225     ierr = PetscSectionGetChart(plex->supportSection, &pStart, &pEnd);CHKERRQ(ierr);
226     for (p = pStart; p < pEnd; ++p) {
227       PetscInt dof, off, offNew, d;
228 
229       ierr = PetscSectionGetDof(plexNew->supportSection, pperm[p], &dof);CHKERRQ(ierr);
230       ierr = PetscSectionGetOffset(plex->supportSection, p, &off);CHKERRQ(ierr);
231       ierr = PetscSectionGetOffset(plexNew->supportSection, pperm[p], &offNew);CHKERRQ(ierr);
232       for (d = 0; d < dof; ++d) {
233         plexNew->supports[offNew+d] = pperm[plex->supports[off+d]];
234       }
235     }
236     ierr = ISRestoreIndices(perm, &pperm);CHKERRQ(ierr);
237   }
238   PetscFunctionReturn(0);
239 }
240