xref: /petsc/src/ksp/pc/impls/gamg/geo.c (revision 8cc058d9cd56c1ccb3be12a47760ddfc446aaffc)
1 /*
2  GAMG geometric-algebric multiogrid PC - Mark Adams 2011
3  */
4 
5 #include <../src/ksp/pc/impls/gamg/gamg.h>        /*I "petscpc.h" I*/
6 #include <petsc-private/kspimpl.h>
7 
8 #if defined(PETSC_HAVE_TRIANGLE)
9 #define REAL PetscReal
10 #include <triangle.h>
11 #endif
12 
13 #include <petscblaslapack.h>
14 
15 /* Private context for the GAMG preconditioner */
16 typedef struct {
17   PetscInt lid;            /* local vertex index */
18   PetscInt degree;         /* vertex degree */
19 } GAMGNode;
20 
21 int petsc_geo_mg_compare(const void *a, const void *b)
22 {
23   return (((GAMGNode*)a)->degree - ((GAMGNode*)b)->degree);
24 }
25 
26 /* -------------------------------------------------------------------------- */
27 /*
28    PCSetCoordinates_GEO
29 
30    Input Parameter:
31    .  pc - the preconditioner context
32 */
33 #undef __FUNCT__
34 #define __FUNCT__ "PCSetCoordinates_GEO"
35 PetscErrorCode PCSetCoordinates_GEO(PC pc, PetscInt ndm, PetscInt a_nloc, PetscReal *coords)
36 {
37   PC_MG          *mg      = (PC_MG*)pc->data;
38   PC_GAMG        *pc_gamg = (PC_GAMG*)mg->innerctx;
39   PetscErrorCode ierr;
40   PetscInt       arrsz,bs,my0,kk,ii,nloc,Iend;
41   Mat            Amat = pc->pmat;
42 
43   PetscFunctionBegin;
44   PetscValidHeaderSpecific(Amat, MAT_CLASSID, 1);
45   ierr = MatGetBlockSize(Amat, &bs);CHKERRQ(ierr);
46 
47   ierr = MatGetOwnershipRange(Amat, &my0, &Iend);CHKERRQ(ierr);
48   nloc = (Iend-my0)/bs;
49 
50   if (nloc!=a_nloc) SETERRQ2(PetscObjectComm((PetscObject)Amat),PETSC_ERR_ARG_WRONG, "Stokes not supported nloc = %d %d.",a_nloc,nloc);
51   if ((Iend-my0)%bs!=0) SETERRQ1(PetscObjectComm((PetscObject)Amat),PETSC_ERR_ARG_WRONG, "Bad local size %d.",nloc);
52 
53   pc_gamg->data_cell_rows = 1;
54   if (coords==0 && nloc > 0) SETERRQ(PetscObjectComm((PetscObject)Amat),PETSC_ERR_ARG_WRONG, "Need coordinates for pc_gamg_type 'geo'.");
55   pc_gamg->data_cell_cols = ndm; /* coordinates */
56 
57   arrsz = nloc*pc_gamg->data_cell_rows*pc_gamg->data_cell_cols;
58 
59   /* create data - syntactic sugar that should be refactored at some point */
60   if (pc_gamg->data==0 || (pc_gamg->data_sz != arrsz)) {
61     ierr = PetscFree(pc_gamg->data);CHKERRQ(ierr);
62     ierr = PetscMalloc((arrsz+1)*sizeof(PetscReal), &pc_gamg->data);CHKERRQ(ierr);
63   }
64   for (kk=0; kk<arrsz; kk++) pc_gamg->data[kk] = -999.;
65   pc_gamg->data[arrsz] = -99.;
66   /* copy data in - column oriented */
67   for (kk = 0; kk < nloc; kk++) {
68     for (ii = 0; ii < ndm; ii++) {
69       pc_gamg->data[ii*nloc + kk] =  coords[kk*ndm + ii];
70     }
71   }
72   if (pc_gamg->data[arrsz] != -99.) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"pc_gamg->data[arrsz %D] %g != -99.",arrsz,pc_gamg->data[arrsz]);
73   pc_gamg->data_sz = arrsz;
74   PetscFunctionReturn(0);
75 }
76 
77 /* -------------------------------------------------------------------------- */
78 /*
79    PCSetData_GEO
80 
81   Input Parameter:
82    . pc -
83 */
84 #undef __FUNCT__
85 #define __FUNCT__ "PCSetData_GEO"
86 PetscErrorCode PCSetData_GEO(PC pc, Mat m)
87 {
88   PetscFunctionBegin;
89   SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_PLIB,"GEO MG needs coordinates");
90 }
91 
92 /* -------------------------------------------------------------------------- */
93 /*
94    PCSetFromOptions_GEO
95 
96   Input Parameter:
97    . pc -
98 */
99 #undef __FUNCT__
100 #define __FUNCT__ "PCSetFromOptions_GEO"
101 PetscErrorCode PCSetFromOptions_GEO(PC pc)
102 {
103   PetscErrorCode ierr;
104   PC_MG          *mg      = (PC_MG*)pc->data;
105   PC_GAMG        *pc_gamg = (PC_GAMG*)mg->innerctx;
106 
107   PetscFunctionBegin;
108   ierr = PetscOptionsHead("GAMG-GEO options");CHKERRQ(ierr);
109   {
110     /* -pc_gamg_sa_nsmooths */
111     /* pc_gamg_sa->smooths = 0; */
112     /* ierr = PetscOptionsInt("-pc_gamg_agg_nsmooths", */
113     /*                        "smoothing steps for smoothed aggregation, usually 1 (0)", */
114     /*                        "PCGAMGSetNSmooths_AGG", */
115     /*                        pc_gamg_sa->smooths, */
116     /*                        &pc_gamg_sa->smooths, */
117     /*                        &flag);  */
118     /* CHKERRQ(ierr); */
119   }
120   ierr = PetscOptionsTail();CHKERRQ(ierr);
121 
122   /* call base class */
123   ierr = PCSetFromOptions_GAMG(pc);CHKERRQ(ierr);
124 
125   if (pc_gamg->verbose) {
126     PetscPrintf(PetscObjectComm((PetscObject)pc),"[%d]%s done\n",0,__FUNCT__);
127   }
128   PetscFunctionReturn(0);
129 }
130 
131 /* -------------------------------------------------------------------------- */
132 /*
133  triangulateAndFormProl
134 
135    Input Parameter:
136    . selected_2 - list of selected local ID, includes selected ghosts
137    . data_stride -
138    . coords[2*data_stride] - column vector of local coordinates w/ ghosts
139    . nselected_1 - selected IDs that go with base (1) graph
140    . clid_lid_1[nselected_1] - lids of selected (c) nodes   ???????????
141    . agg_lists_1 - list of aggregates
142    . crsGID[selected.size()] - global index for prolongation operator
143    . bs - block size
144   Output Parameter:
145    . a_Prol - prolongation operator
146    . a_worst_best - measure of worst missed fine vertex, 0 is no misses
147 */
148 #undef __FUNCT__
149 #define __FUNCT__ "triangulateAndFormProl"
150 static PetscErrorCode triangulateAndFormProl(IS  selected_2, /* list of selected local ID, includes selected ghosts */
151                                              const PetscInt data_stride,
152                                              const PetscReal coords[], /* column vector of local coordinates w/ ghosts */
153                                              const PetscInt nselected_1, /* list of selected local ID, includes selected ghosts */
154                                              const PetscInt clid_lid_1[],
155                                              const PetscCoarsenData *agg_lists_1, /* selected_1 vertices of aggregate unselected vertices */
156                                              const PetscInt crsGID[],
157                                              const PetscInt bs,
158                                              Mat a_Prol, /* prolongation operator (output) */
159                                              PetscReal *a_worst_best) /* measure of worst missed fine vertex, 0 is no misses */
160 {
161 #if defined(PETSC_HAVE_TRIANGLE)
162   PetscErrorCode       ierr;
163   PetscInt             jj,tid,tt,idx,nselected_2;
164   struct triangulateio in,mid;
165   const PetscInt       *selected_idx_2;
166   PetscMPIInt          rank,size;
167   PetscInt             Istart,Iend,nFineLoc,myFine0;
168   int                  kk,nPlotPts,sid;
169   MPI_Comm             comm;
170   PetscReal            tm;
171 
172   PetscFunctionBegin;
173   ierr = PetscObjectGetComm((PetscObject)a_Prol,&comm);CHKERRQ(ierr);
174   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
175   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
176   ierr = ISGetSize(selected_2, &nselected_2);CHKERRQ(ierr);
177   if (nselected_2 == 1 || nselected_2 == 2) { /* 0 happens on idle processors */
178     *a_worst_best = 100.0; /* this will cause a stop, but not globalized (should not happen) */
179   } else *a_worst_best = 0.0;
180   ierr = MPI_Allreduce(a_worst_best, &tm, 1, MPIU_REAL, MPIU_MAX, comm);CHKERRQ(ierr);
181   if (tm > 0.0) {
182     *a_worst_best = 100.0;
183     PetscFunctionReturn(0);
184   }
185   ierr     = MatGetOwnershipRange(a_Prol, &Istart, &Iend);CHKERRQ(ierr);
186   nFineLoc = (Iend-Istart)/bs; myFine0 = Istart/bs;
187   nPlotPts = nFineLoc; /* locals */
188   /* traingle */
189   /* Define input points - in*/
190   in.numberofpoints          = nselected_2;
191   in.numberofpointattributes = 0;
192   /* get nselected points */
193   ierr = PetscMalloc(2*(nselected_2)*sizeof(REAL), &in.pointlist);CHKERRQ(ierr);
194   ierr = ISGetIndices(selected_2, &selected_idx_2);CHKERRQ(ierr);
195 
196   for (kk=0,sid=0; kk<nselected_2; kk++,sid += 2) {
197     PetscInt lid = selected_idx_2[kk];
198     in.pointlist[sid]   = coords[lid];
199     in.pointlist[sid+1] = coords[data_stride + lid];
200     if (lid>=nFineLoc) nPlotPts++;
201   }
202   if (sid != 2*nselected_2) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"sid %D != 2*nselected_2 %D",sid,nselected_2);
203 
204   in.numberofsegments      = 0;
205   in.numberofedges         = 0;
206   in.numberofholes         = 0;
207   in.numberofregions       = 0;
208   in.trianglelist          = 0;
209   in.segmentmarkerlist     = 0;
210   in.pointattributelist    = 0;
211   in.pointmarkerlist       = 0;
212   in.triangleattributelist = 0;
213   in.trianglearealist      = 0;
214   in.segmentlist           = 0;
215   in.holelist              = 0;
216   in.regionlist            = 0;
217   in.edgelist              = 0;
218   in.edgemarkerlist        = 0;
219   in.normlist              = 0;
220 
221   /* triangulate */
222   mid.pointlist = 0;            /* Not needed if -N switch used. */
223   /* Not needed if -N switch used or number of point attributes is zero: */
224   mid.pointattributelist = 0;
225   mid.pointmarkerlist    = 0; /* Not needed if -N or -B switch used. */
226   mid.trianglelist       = 0;    /* Not needed if -E switch used. */
227   /* Not needed if -E switch used or number of triangle attributes is zero: */
228   mid.triangleattributelist = 0;
229   mid.neighborlist          = 0; /* Needed only if -n switch used. */
230   /* Needed only if segments are output (-p or -c) and -P not used: */
231   mid.segmentlist = 0;
232   /* Needed only if segments are output (-p or -c) and -P and -B not used: */
233   mid.segmentmarkerlist = 0;
234   mid.edgelist          = 0;    /* Needed only if -e switch used. */
235   mid.edgemarkerlist    = 0; /* Needed if -e used and -B not used. */
236   mid.numberoftriangles = 0;
237 
238   /* Triangulate the points.  Switches are chosen to read and write a  */
239   /*   PSLG (p), preserve the convex hull (c), number everything from  */
240   /*   zero (z), assign a regional attribute to each element (A), and  */
241   /*   produce an edge list (e), a Voronoi diagram (v), and a triangle */
242   /*   neighbor list (n).                                            */
243   if (nselected_2 != 0) { /* inactive processor */
244     char args[] = "npczQ"; /* c is needed ? */
245     triangulate(args, &in, &mid, (struct triangulateio*) NULL);
246     /* output .poly files for 'showme' */
247     if (!PETSC_TRUE) {
248       static int level = 1;
249       FILE       *file; char fname[32];
250 
251       sprintf(fname,"C%d_%d.poly",level,rank); file = fopen(fname, "w");
252       /*First line: <# of vertices> <dimension (must be 2)> <# of attributes> <# of boundary markers (0 or 1)>*/
253       fprintf(file, "%d  %d  %d  %d\n",in.numberofpoints,2,0,0);
254       /*Following lines: <vertex #> <x> <y> */
255       for (kk=0,sid=0; kk<in.numberofpoints; kk++,sid += 2) {
256         fprintf(file, "%d %e %e\n",kk,in.pointlist[sid],in.pointlist[sid+1]);
257       }
258       /*One line: <# of segments> <# of boundary markers (0 or 1)> */
259       fprintf(file, "%d  %d\n",0,0);
260       /*Following lines: <segment #> <endpoint> <endpoint> [boundary marker] */
261       /* One line: <# of holes> */
262       fprintf(file, "%d\n",0);
263       /* Following lines: <hole #> <x> <y> */
264       /* Optional line: <# of regional attributes and/or area constraints> */
265       /* Optional following lines: <region #> <x> <y> <attribute> <maximum area> */
266       fclose(file);
267 
268       /* elems */
269       sprintf(fname,"C%d_%d.ele",level,rank); file = fopen(fname, "w");
270       /* First line: <# of triangles> <nodes per triangle> <# of attributes> */
271       fprintf(file, "%d %d %d\n",mid.numberoftriangles,3,0);
272       /* Remaining lines: <triangle #> <node> <node> <node> ... [attributes] */
273       for (kk=0,sid=0; kk<mid.numberoftriangles; kk++,sid += 3) {
274         fprintf(file, "%d %d %d %d\n",kk,mid.trianglelist[sid],mid.trianglelist[sid+1],mid.trianglelist[sid+2]);
275       }
276       fclose(file);
277 
278       sprintf(fname,"C%d_%d.node",level,rank); file = fopen(fname, "w");
279       /* First line: <# of vertices> <dimension (must be 2)> <# of attributes> <# of boundary markers (0 or 1)> */
280       /* fprintf(file, "%d  %d  %d  %d\n",in.numberofpoints,2,0,0); */
281       fprintf(file, "%d  %d  %d  %d\n",nPlotPts,2,0,0);
282       /*Following lines: <vertex #> <x> <y> */
283       for (kk=0,sid=0; kk<in.numberofpoints; kk++,sid+=2) {
284         fprintf(file, "%d %e %e\n",kk,in.pointlist[sid],in.pointlist[sid+1]);
285       }
286 
287       sid /= 2;
288       for (jj=0; jj<nFineLoc; jj++) {
289         PetscBool sel = PETSC_TRUE;
290         for (kk=0; kk<nselected_2 && sel; kk++) {
291           PetscInt lid = selected_idx_2[kk];
292           if (lid == jj) sel = PETSC_FALSE;
293         }
294         if (sel) fprintf(file, "%d %e %e\n",sid++,coords[jj],coords[data_stride + jj]);
295       }
296       fclose(file);
297       if (sid != nPlotPts) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"sid %D != nPlotPts %D",sid,nPlotPts);
298       level++;
299     }
300   }
301 #if defined PETSC_GAMG_USE_LOG
302   ierr = PetscLogEventBegin(petsc_gamg_setup_events[FIND_V],0,0,0,0);CHKERRQ(ierr);
303 #endif
304   { /* form P - setup some maps */
305     PetscInt clid,mm,*nTri,*node_tri;
306 
307     ierr = PetscMalloc(nselected_2*sizeof(PetscInt), &node_tri);CHKERRQ(ierr);
308     ierr = PetscMalloc(nselected_2*sizeof(PetscInt), &nTri);CHKERRQ(ierr);
309 
310     /* need list of triangles on node */
311     for (kk=0; kk<nselected_2; kk++) nTri[kk] = 0;
312     for (tid=0,kk=0; tid<mid.numberoftriangles; tid++) {
313       for (jj=0; jj<3; jj++) {
314         PetscInt cid = mid.trianglelist[kk++];
315         if (nTri[cid] == 0) node_tri[cid] = tid;
316         nTri[cid]++;
317       }
318     }
319 #define EPS 1.e-12
320     /* find points and set prolongation */
321     for (mm = clid = 0; mm < nFineLoc; mm++) {
322       PetscBool ise;
323       ierr = PetscCDEmptyAt(agg_lists_1,mm,&ise);CHKERRQ(ierr);
324       if (!ise) {
325         const PetscInt lid = mm;
326         /* for (clid_iterator=0;clid_iterator<nselected_1;clid_iterator++) { */
327         PetscScalar  AA[3][3];
328         PetscBLASInt N=3,NRHS=1,LDA=3,IPIV[3],LDB=3,INFO;
329         PetscCDPos   pos;
330         ierr = PetscCDGetHeadPos(agg_lists_1,lid,&pos);CHKERRQ(ierr);
331         while (pos) {
332           PetscInt flid;
333           ierr = PetscLLNGetID(pos, &flid);CHKERRQ(ierr);
334           ierr = PetscCDGetNextPos(agg_lists_1,lid,&pos);CHKERRQ(ierr);
335 
336           if (flid < nFineLoc) {  /* could be a ghost */
337             PetscInt       bestTID = -1; PetscReal best_alpha = 1.e10;
338             const PetscInt fgid    = flid + myFine0;
339             /* compute shape function for gid */
340             const PetscReal fcoord[3] = {coords[flid],coords[data_stride+flid],1.0};
341             PetscBool       haveit    =PETSC_FALSE; PetscScalar alpha[3]; PetscInt clids[3];
342 
343             /* look for it */
344             for (tid = node_tri[clid], jj=0;
345                  jj < 5 && !haveit && tid != -1;
346                  jj++) {
347               for (tt=0; tt<3; tt++) {
348                 PetscInt cid2 = mid.trianglelist[3*tid + tt];
349                 PetscInt lid2 = selected_idx_2[cid2];
350                 AA[tt][0] = coords[lid2]; AA[tt][1] = coords[data_stride + lid2]; AA[tt][2] = 1.0;
351                 clids[tt] = cid2; /* store for interp */
352               }
353 
354               for (tt=0; tt<3; tt++) alpha[tt] = (PetscScalar)fcoord[tt];
355 
356               /* SUBROUTINE DGESV(N, NRHS, A, LDA, IPIV, B, LDB, INFO) */
357               PetscStackCall("LAPACKgesv",LAPACKgesv_(&N, &NRHS, (PetscScalar*)AA, &LDA, IPIV, alpha, &LDB, &INFO));
358               {
359                 PetscBool have=PETSC_TRUE;  PetscReal lowest=1.e10;
360                 for (tt = 0, idx = 0; tt < 3; tt++) {
361                   if (PetscRealPart(alpha[tt]) > (1.0+EPS) || PetscRealPart(alpha[tt]) < -EPS) have = PETSC_FALSE;
362                   if (PetscRealPart(alpha[tt]) < lowest) {
363                     lowest = PetscRealPart(alpha[tt]);
364                     idx    = tt;
365                   }
366                 }
367                 haveit = have;
368               }
369               tid = mid.neighborlist[3*tid + idx];
370             }
371 
372             if (!haveit) {
373               /* brute force */
374               for (tid=0; tid<mid.numberoftriangles && !haveit; tid++) {
375                 for (tt=0; tt<3; tt++) {
376                   PetscInt cid2 = mid.trianglelist[3*tid + tt];
377                   PetscInt lid2 = selected_idx_2[cid2];
378                   AA[tt][0] = coords[lid2]; AA[tt][1] = coords[data_stride + lid2]; AA[tt][2] = 1.0;
379                   clids[tt] = cid2; /* store for interp */
380                 }
381                 for (tt=0; tt<3; tt++) alpha[tt] = fcoord[tt];
382                 /* SUBROUTINE DGESV(N, NRHS, A, LDA, IPIV, B, LDB, INFO) */
383                 PetscStackCall("LAPACKgesv",LAPACKgesv_(&N, &NRHS, (PetscScalar*)AA, &LDA, IPIV, alpha, &LDB, &INFO));
384                 {
385                   PetscBool have=PETSC_TRUE;  PetscReal worst=0.0, v;
386                   for (tt=0; tt<3 && have; tt++) {
387                     if (PetscRealPart(alpha[tt]) > 1.0+EPS || PetscRealPart(alpha[tt]) < -EPS) have=PETSC_FALSE;
388                     if ((v=PetscAbs(PetscRealPart(alpha[tt])-0.5)) > worst) worst = v;
389                   }
390                   if (worst < best_alpha) {
391                     best_alpha = worst; bestTID = tid;
392                   }
393                   haveit = have;
394                 }
395               }
396             }
397             if (!haveit) {
398               if (best_alpha > *a_worst_best) *a_worst_best = best_alpha;
399               /* use best one */
400               for (tt=0; tt<3; tt++) {
401                 PetscInt cid2 = mid.trianglelist[3*bestTID + tt];
402                 PetscInt lid2 = selected_idx_2[cid2];
403                 AA[tt][0] = coords[lid2]; AA[tt][1] = coords[data_stride + lid2]; AA[tt][2] = 1.0;
404                 clids[tt] = cid2; /* store for interp */
405               }
406               for (tt=0; tt<3; tt++) alpha[tt] = fcoord[tt];
407               /* SUBROUTINE DGESV(N, NRHS, A, LDA, IPIV, B, LDB, INFO) */
408               PetscStackCall("LAPACKgesv",LAPACKgesv_(&N, &NRHS, (PetscScalar*)AA, &LDA, IPIV, alpha, &LDB, &INFO));
409             }
410 
411             /* put in row of P */
412             for (idx=0; idx<3; idx++) {
413               PetscScalar shp = alpha[idx];
414               if (PetscAbs(PetscRealPart(shp)) > 1.e-6) {
415                 PetscInt cgid = crsGID[clids[idx]];
416                 PetscInt jj   = cgid*bs, ii = fgid*bs; /* need to gloalize */
417                 for (tt=0; tt < bs; tt++, ii++, jj++) {
418                   ierr = MatSetValues(a_Prol,1,&ii,1,&jj,&shp,INSERT_VALUES);CHKERRQ(ierr);
419                 }
420               }
421             }
422           }
423         } /* aggregates iterations */
424         clid++;
425       } /* a coarse agg */
426     } /* for all fine nodes */
427 
428     ierr = ISRestoreIndices(selected_2, &selected_idx_2);CHKERRQ(ierr);
429     ierr = MatAssemblyBegin(a_Prol,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
430     ierr = MatAssemblyEnd(a_Prol,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
431 
432     ierr = PetscFree(node_tri);CHKERRQ(ierr);
433     ierr = PetscFree(nTri);CHKERRQ(ierr);
434   }
435 #if defined PETSC_GAMG_USE_LOG
436   ierr = PetscLogEventEnd(petsc_gamg_setup_events[FIND_V],0,0,0,0);CHKERRQ(ierr);
437 #endif
438   free(mid.trianglelist);
439   free(mid.neighborlist);
440   ierr = PetscFree(in.pointlist);CHKERRQ(ierr);
441   PetscFunctionReturn(0);
442 #else
443   SETERRQ(PetscObjectComm((PetscObject)a_Prol),PETSC_ERR_PLIB,"configure with TRIANGLE to use geometric MG");
444 #endif
445 }
446 /* -------------------------------------------------------------------------- */
447 /*
448    getGIDsOnSquareGraph - square graph, get
449 
450    Input Parameter:
451    . nselected_1 - selected local indices (includes ghosts in input Gmat1)
452    . clid_lid_1 - [nselected_1] lids of selected nodes
453    . Gmat1 - graph that goes with 'selected_1'
454    Output Parameter:
455    . a_selected_2 - selected local indices (includes ghosts in output a_Gmat_2)
456    . a_Gmat_2 - graph that is squared of 'Gmat_1'
457    . a_crsGID[a_selected_2.size()] - map of global IDs of coarse grid nodes
458 */
459 #undef __FUNCT__
460 #define __FUNCT__ "getGIDsOnSquareGraph"
461 static PetscErrorCode getGIDsOnSquareGraph(const PetscInt nselected_1,const PetscInt clid_lid_1[],const Mat Gmat1,IS *a_selected_2,Mat *a_Gmat_2,PetscInt **a_crsGID)
462 {
463   PetscErrorCode ierr;
464   PetscMPIInt    rank,size;
465   PetscInt       *crsGID, kk,my0,Iend,nloc;
466   MPI_Comm       comm;
467 
468   PetscFunctionBegin;
469   ierr = PetscObjectGetComm((PetscObject)Gmat1,&comm);CHKERRQ(ierr);
470   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
471   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
472   ierr = MatGetOwnershipRange(Gmat1,&my0,&Iend);CHKERRQ(ierr); /* AIJ */
473   nloc = Iend - my0; /* this does not change */
474 
475   if (size == 1) { /* not much to do in serial */
476     ierr = PetscMalloc(nselected_1*sizeof(PetscInt), &crsGID);CHKERRQ(ierr);
477     for (kk=0; kk<nselected_1; kk++) crsGID[kk] = kk;
478     *a_Gmat_2 = 0;
479     ierr      = ISCreateGeneral(PETSC_COMM_SELF,nselected_1,clid_lid_1,PETSC_COPY_VALUES,a_selected_2);CHKERRQ(ierr);
480   } else {
481     PetscInt    idx,num_fine_ghosts,num_crs_ghost,myCrs0;
482     Mat_MPIAIJ  *mpimat2;
483     Mat         Gmat2;
484     Vec         locState;
485     PetscScalar *cpcol_state;
486 
487     /* scan my coarse zero gid, set 'lid_state' with coarse GID */
488     kk = nselected_1;
489     MPI_Scan(&kk, &myCrs0, 1, MPIU_INT, MPIU_SUM, comm);
490     myCrs0 -= nselected_1;
491 
492     if (a_Gmat_2) { /* output */
493       /* grow graph to get wider set of selected vertices to cover fine grid, invalidates 'llist' */
494       ierr      = MatTransposeMatMult(Gmat1, Gmat1, MAT_INITIAL_MATRIX, PETSC_DEFAULT, &Gmat2);CHKERRQ(ierr);
495       *a_Gmat_2 = Gmat2; /* output */
496     } else Gmat2 = Gmat1;  /* use local to get crsGIDs at least */
497     /* get coarse grid GIDS for selected (locals and ghosts) */
498     mpimat2 = (Mat_MPIAIJ*)Gmat2->data;
499     ierr    = MatGetVecs(Gmat2, &locState, 0);CHKERRQ(ierr);
500     ierr    = VecSet(locState, (PetscScalar)(PetscReal)(-1));CHKERRQ(ierr); /* set with UNKNOWN state */
501     for (kk=0; kk<nselected_1; kk++) {
502       PetscInt    fgid = clid_lid_1[kk] + my0;
503       PetscScalar v    = (PetscScalar)(kk+myCrs0);
504       ierr = VecSetValues(locState, 1, &fgid, &v, INSERT_VALUES);CHKERRQ(ierr); /* set with PID */
505     }
506     ierr = VecAssemblyBegin(locState);CHKERRQ(ierr);
507     ierr = VecAssemblyEnd(locState);CHKERRQ(ierr);
508     ierr = VecScatterBegin(mpimat2->Mvctx,locState,mpimat2->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
509     ierr =   VecScatterEnd(mpimat2->Mvctx,locState,mpimat2->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
510     ierr = VecGetLocalSize(mpimat2->lvec, &num_fine_ghosts);CHKERRQ(ierr);
511     ierr = VecGetArray(mpimat2->lvec, &cpcol_state);CHKERRQ(ierr);
512     for (kk=0,num_crs_ghost=0; kk<num_fine_ghosts; kk++) {
513       if ((PetscInt)PetscRealPart(cpcol_state[kk]) != -1) num_crs_ghost++;
514     }
515     ierr = PetscMalloc((nselected_1+num_crs_ghost)*sizeof(PetscInt), &crsGID);CHKERRQ(ierr); /* output */
516     {
517       PetscInt *selected_set;
518       ierr = PetscMalloc((nselected_1+num_crs_ghost)*sizeof(PetscInt), &selected_set);CHKERRQ(ierr);
519       /* do ghost of 'crsGID' */
520       for (kk=0,idx=nselected_1; kk<num_fine_ghosts; kk++) {
521         if ((PetscInt)PetscRealPart(cpcol_state[kk]) != -1) {
522           PetscInt cgid = (PetscInt)PetscRealPart(cpcol_state[kk]);
523           selected_set[idx] = nloc + kk;
524           crsGID[idx++]     = cgid;
525         }
526       }
527       if (idx != (nselected_1+num_crs_ghost)) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_PLIB,"idx %D != (nselected_1 %D + num_crs_ghost %D)",idx,nselected_1,num_crs_ghost);
528       ierr = VecRestoreArray(mpimat2->lvec, &cpcol_state);CHKERRQ(ierr);
529       /* do locals in 'crsGID' */
530       ierr = VecGetArray(locState, &cpcol_state);CHKERRQ(ierr);
531       for (kk=0,idx=0; kk<nloc; kk++) {
532         if ((PetscInt)PetscRealPart(cpcol_state[kk]) != -1) {
533           PetscInt cgid = (PetscInt)PetscRealPart(cpcol_state[kk]);
534           selected_set[idx] = kk;
535           crsGID[idx++]     = cgid;
536         }
537       }
538       if (idx != nselected_1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"idx %D != nselected_1 %D",idx,nselected_1);
539       ierr = VecRestoreArray(locState, &cpcol_state);CHKERRQ(ierr);
540 
541       if (a_selected_2 != 0) { /* output */
542         ierr = ISCreateGeneral(PETSC_COMM_SELF,(nselected_1+num_crs_ghost),selected_set,PETSC_OWN_POINTER,a_selected_2);CHKERRQ(ierr);
543       } else {
544         ierr = PetscFree(selected_set);CHKERRQ(ierr);
545       }
546     }
547     ierr = VecDestroy(&locState);CHKERRQ(ierr);
548   }
549   *a_crsGID = crsGID; /* output */
550   PetscFunctionReturn(0);
551 }
552 
553 /* -------------------------------------------------------------------------- */
554 /*
555    PCGAMGgraph_GEO
556 
557   Input Parameter:
558    . pc - this
559    . Amat - matrix on this fine level
560   Output Parameter:
561    . a_Gmat
562 */
563 #undef __FUNCT__
564 #define __FUNCT__ "PCGAMGgraph_GEO"
565 PetscErrorCode PCGAMGgraph_GEO(PC pc,const Mat Amat,Mat *a_Gmat)
566 {
567   PetscErrorCode  ierr;
568   PC_MG           *mg      = (PC_MG*)pc->data;
569   PC_GAMG         *pc_gamg = (PC_GAMG*)mg->innerctx;
570   const PetscInt  verbose  = pc_gamg->verbose;
571   const PetscReal vfilter  = pc_gamg->threshold;
572   PetscMPIInt     rank,size;
573   MPI_Comm        comm;
574   Mat             Gmat;
575   PetscBool       set,flg,symm;
576 
577   PetscFunctionBegin;
578   ierr = PetscObjectGetComm((PetscObject)Amat,&comm);CHKERRQ(ierr);
579 #if defined PETSC_USE_LOG
580   ierr = PetscLogEventBegin(PC_GAMGGgraph_GEO,0,0,0,0);CHKERRQ(ierr);
581 #endif
582   ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr);
583   ierr = MPI_Comm_size(comm, &size);CHKERRQ(ierr);
584 
585   ierr = MatIsSymmetricKnown(Amat, &set, &flg);CHKERRQ(ierr);
586   symm = (PetscBool)!(set && flg);
587 
588   ierr = PCGAMGCreateGraph(Amat, &Gmat);CHKERRQ(ierr);
589   ierr = PCGAMGFilterGraph(&Gmat, vfilter, symm, verbose);CHKERRQ(ierr);
590 
591   *a_Gmat = Gmat;
592 #if defined PETSC_USE_LOG
593   ierr = PetscLogEventEnd(PC_GAMGGgraph_GEO,0,0,0,0);CHKERRQ(ierr);
594 #endif
595   PetscFunctionReturn(0);
596 }
597 
598 /* -------------------------------------------------------------------------- */
599 /*
600    PCGAMGcoarsen_GEO
601 
602   Input Parameter:
603    . a_pc - this
604    . a_Gmat - graph
605   Output Parameter:
606    . a_llist_parent - linked list from selected indices for data locality only
607 */
608 #undef __FUNCT__
609 #define __FUNCT__ "PCGAMGcoarsen_GEO"
610 PetscErrorCode PCGAMGcoarsen_GEO(PC a_pc,Mat *a_Gmat,PetscCoarsenData **a_llist_parent)
611 {
612   PetscErrorCode ierr;
613   PC_MG          *mg      = (PC_MG*)a_pc->data;
614   PC_GAMG        *pc_gamg = (PC_GAMG*)mg->innerctx;
615   PetscInt       Istart,Iend,nloc,kk,Ii,ncols;
616   PetscMPIInt    rank,size;
617   IS             perm;
618   GAMGNode       *gnodes;
619   PetscInt       *permute;
620   Mat            Gmat  = *a_Gmat;
621   MPI_Comm       comm;
622   MatCoarsen     crs;
623 
624   PetscFunctionBegin;
625   ierr = PetscObjectGetComm((PetscObject)a_pc,&comm);CHKERRQ(ierr);
626 #if defined PETSC_USE_LOG
627   ierr = PetscLogEventBegin(PC_GAMGCoarsen_GEO,0,0,0,0);CHKERRQ(ierr);
628 #endif
629   ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr);
630   ierr = MPI_Comm_size(comm, &size);CHKERRQ(ierr);
631   ierr = MatGetOwnershipRange(Gmat, &Istart, &Iend);CHKERRQ(ierr);
632   nloc = (Iend-Istart);
633 
634   /* create random permutation with sort for geo-mg */
635   ierr = PetscMalloc(nloc*sizeof(GAMGNode), &gnodes);CHKERRQ(ierr);
636   ierr = PetscMalloc(nloc*sizeof(PetscInt), &permute);CHKERRQ(ierr);
637 
638   for (Ii=Istart; Ii<Iend; Ii++) { /* locals only? */
639     ierr = MatGetRow(Gmat,Ii,&ncols,0,0);CHKERRQ(ierr);
640     {
641       PetscInt lid = Ii - Istart;
642       gnodes[lid].lid    = lid;
643       gnodes[lid].degree = ncols;
644     }
645     ierr = MatRestoreRow(Gmat,Ii,&ncols,0,0);CHKERRQ(ierr);
646   }
647   /* randomize */
648   srand(1); /* make deterministic */
649   if (PETSC_TRUE) {
650     PetscBool *bIndexSet;
651     ierr = PetscMalloc(nloc*sizeof(PetscBool), &bIndexSet);CHKERRQ(ierr);
652     for (Ii = 0; Ii < nloc; Ii++) bIndexSet[Ii] = PETSC_FALSE;
653     for (Ii = 0; Ii < nloc; Ii++) {
654       PetscInt iSwapIndex = rand()%nloc;
655       if (!bIndexSet[iSwapIndex] && iSwapIndex != Ii) {
656         GAMGNode iTemp = gnodes[iSwapIndex];
657         gnodes[iSwapIndex]    = gnodes[Ii];
658         gnodes[Ii]            = iTemp;
659         bIndexSet[Ii]         = PETSC_TRUE;
660         bIndexSet[iSwapIndex] = PETSC_TRUE;
661       }
662     }
663     ierr = PetscFree(bIndexSet);CHKERRQ(ierr);
664   }
665   /* only sort locals */
666   qsort(gnodes, nloc, sizeof(GAMGNode), petsc_geo_mg_compare);
667   /* create IS of permutation */
668   for (kk=0; kk<nloc; kk++) permute[kk] = gnodes[kk].lid; /* locals only */
669   ierr = ISCreateGeneral(PETSC_COMM_SELF, nloc, permute, PETSC_OWN_POINTER, &perm);CHKERRQ(ierr);
670 
671   ierr = PetscFree(gnodes);CHKERRQ(ierr);
672 
673   /* get MIS aggs */
674 
675   ierr = MatCoarsenCreate(comm, &crs);CHKERRQ(ierr);
676   ierr = MatCoarsenSetType(crs, MATCOARSENMIS);CHKERRQ(ierr);
677   ierr = MatCoarsenSetGreedyOrdering(crs, perm);CHKERRQ(ierr);
678   ierr = MatCoarsenSetAdjacency(crs, Gmat);CHKERRQ(ierr);
679   ierr = MatCoarsenSetVerbose(crs, pc_gamg->verbose);CHKERRQ(ierr);
680   ierr = MatCoarsenSetStrictAggs(crs, PETSC_FALSE);CHKERRQ(ierr);
681   ierr = MatCoarsenApply(crs);CHKERRQ(ierr);
682   ierr = MatCoarsenGetData(crs, a_llist_parent);CHKERRQ(ierr);
683   ierr = MatCoarsenDestroy(&crs);CHKERRQ(ierr);
684 
685   ierr = ISDestroy(&perm);CHKERRQ(ierr);
686 #if defined PETSC_USE_LOG
687   ierr = PetscLogEventEnd(PC_GAMGCoarsen_GEO,0,0,0,0);CHKERRQ(ierr);
688 #endif
689   PetscFunctionReturn(0);
690 }
691 
692 /* -------------------------------------------------------------------------- */
693 /*
694  PCGAMGProlongator_GEO
695 
696  Input Parameter:
697  . pc - this
698  . Amat - matrix on this fine level
699  . Graph - used to get ghost data for nodes in
700  . selected_1 - [nselected]
701  . agg_lists - [nselected]
702  Output Parameter:
703  . a_P_out - prolongation operator to the next level
704  */
705 #undef __FUNCT__
706 #define __FUNCT__ "PCGAMGProlongator_GEO"
707 PetscErrorCode PCGAMGProlongator_GEO(PC pc,const Mat Amat,const Mat Gmat,PetscCoarsenData *agg_lists,Mat *a_P_out)
708 {
709   PC_MG          *mg      = (PC_MG*)pc->data;
710   PC_GAMG        *pc_gamg = (PC_GAMG*)mg->innerctx;
711   const PetscInt verbose  = pc_gamg->verbose;
712   const PetscInt dim      = pc_gamg->data_cell_cols, data_cols = pc_gamg->data_cell_cols;
713   PetscErrorCode ierr;
714   PetscInt       Istart,Iend,nloc,my0,jj,kk,ncols,nLocalSelected,bs,*clid_flid;
715   Mat            Prol;
716   PetscMPIInt    rank, size;
717   MPI_Comm       comm;
718   IS             selected_2,selected_1;
719   const PetscInt *selected_idx;
720 
721   PetscFunctionBegin;
722   ierr = PetscObjectGetComm((PetscObject)Amat,&comm);CHKERRQ(ierr);
723 #if defined PETSC_USE_LOG
724   ierr = PetscLogEventBegin(PC_GAMGProlongator_GEO,0,0,0,0);CHKERRQ(ierr);
725 #endif
726   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
727   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
728   ierr = MatGetOwnershipRange(Amat, &Istart, &Iend);CHKERRQ(ierr);
729   ierr = MatGetBlockSize(Amat, &bs);CHKERRQ(ierr);
730   nloc = (Iend-Istart)/bs; my0 = Istart/bs;
731   if ((Iend-Istart) % bs) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_PLIB,"(Iend %D - Istart %D) % bs %D",Iend,Istart,bs);
732 
733   /* get 'nLocalSelected' */
734   ierr = PetscCDGetMIS(agg_lists, &selected_1);CHKERRQ(ierr);
735   ierr = ISGetSize(selected_1, &jj);CHKERRQ(ierr);
736   ierr = PetscMalloc(jj*sizeof(PetscInt), &clid_flid);CHKERRQ(ierr);
737   ierr = ISGetIndices(selected_1, &selected_idx);CHKERRQ(ierr);
738   for (kk=0,nLocalSelected=0; kk<jj; kk++) {
739     PetscInt lid = selected_idx[kk];
740     if (lid<nloc) {
741       ierr = MatGetRow(Gmat,lid+my0,&ncols,0,0);CHKERRQ(ierr);
742       if (ncols>1) clid_flid[nLocalSelected++] = lid; /* fiter out singletons */
743       ierr = MatRestoreRow(Gmat,lid+my0,&ncols,0,0);CHKERRQ(ierr);
744     }
745   }
746   ierr = ISRestoreIndices(selected_1, &selected_idx);CHKERRQ(ierr);
747   ierr = ISDestroy(&selected_1);CHKERRQ(ierr); /* this is selected_1 in serial */
748 
749   /* create prolongator, create P matrix */
750   ierr = MatCreate(comm, &Prol);CHKERRQ(ierr);
751   ierr = MatSetSizes(Prol,nloc*bs,nLocalSelected*bs,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
752   ierr = MatSetBlockSizes(Prol, bs, bs);CHKERRQ(ierr);
753   ierr = MatSetType(Prol, MATAIJ);CHKERRQ(ierr);
754   ierr = MatSeqAIJSetPreallocation(Prol,3*data_cols,NULL);CHKERRQ(ierr);
755   ierr = MatMPIAIJSetPreallocation(Prol,3*data_cols,NULL,3*data_cols,NULL);CHKERRQ(ierr);
756   /* ierr = MatCreateAIJ(comm,  */
757   /*                      nloc*bs, nLocalSelected*bs, */
758   /*                      PETSC_DETERMINE, PETSC_DETERMINE, */
759   /*                      3*data_cols, NULL,  */
760   /*                      3*data_cols, NULL, */
761   /*                      &Prol); */
762   /* CHKERRQ(ierr); */
763 
764   /* can get all points "removed" - but not on geomg */
765   ierr =  MatGetSize(Prol, &kk, &jj);CHKERRQ(ierr);
766   if (jj==0) {
767     if (verbose) PetscPrintf(comm,"[%d]%s ERROE: no selected points on coarse grid\n",rank,__FUNCT__);
768     ierr = PetscFree(clid_flid);CHKERRQ(ierr);
769     ierr = MatDestroy(&Prol);CHKERRQ(ierr);
770     *a_P_out = NULL;  /* out */
771     PetscFunctionReturn(0);
772   }
773 
774   {
775     PetscReal *coords;
776     PetscInt  data_stride;
777     PetscInt  *crsGID = NULL;
778     Mat       Gmat2;
779 
780     if (dim != data_cols) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"dim %D != data_cols %D",dim,data_cols);
781     /* grow ghost data for better coarse grid cover of fine grid */
782 #if defined PETSC_GAMG_USE_LOG
783     ierr = PetscLogEventBegin(petsc_gamg_setup_events[SET5],0,0,0,0);CHKERRQ(ierr);
784 #endif
785     /* messy method, squares graph and gets some data */
786     ierr = getGIDsOnSquareGraph(nLocalSelected, clid_flid, Gmat, &selected_2, &Gmat2, &crsGID);CHKERRQ(ierr);
787     /* llist is now not valid wrt squared graph, but will work as iterator in 'triangulateAndFormProl' */
788 #if defined PETSC_GAMG_USE_LOG
789     ierr = PetscLogEventEnd(petsc_gamg_setup_events[SET5],0,0,0,0);CHKERRQ(ierr);
790 #endif
791     /* create global vector of coorindates in 'coords' */
792     if (size > 1) {
793       ierr = PCGAMGGetDataWithGhosts(Gmat2, dim, pc_gamg->data, &data_stride, &coords);CHKERRQ(ierr);
794     } else {
795       coords      = (PetscReal*)pc_gamg->data;
796       data_stride = pc_gamg->data_sz/pc_gamg->data_cell_cols;
797     }
798     ierr = MatDestroy(&Gmat2);CHKERRQ(ierr);
799 
800     /* triangulate */
801     if (dim == 2) {
802       PetscReal metric,tm;
803 #if defined PETSC_GAMG_USE_LOG
804       ierr = PetscLogEventBegin(petsc_gamg_setup_events[SET6],0,0,0,0);CHKERRQ(ierr);
805 #endif
806       ierr = triangulateAndFormProl(selected_2, data_stride, coords,nLocalSelected, clid_flid, agg_lists, crsGID, bs, Prol, &metric);CHKERRQ(ierr);
807 #if defined PETSC_GAMG_USE_LOG
808       ierr = PetscLogEventEnd(petsc_gamg_setup_events[SET6],0,0,0,0);CHKERRQ(ierr);
809 #endif
810       ierr = PetscFree(crsGID);CHKERRQ(ierr);
811 
812       /* clean up and create coordinates for coarse grid (output) */
813       if (size > 1) ierr = PetscFree(coords);CHKERRQ(ierr);
814 
815       ierr = MPI_Allreduce(&metric, &tm, 1, MPIU_REAL, MPIU_MAX, comm);CHKERRQ(ierr);
816       if (tm > 1.) { /* needs to be globalized - should not happen */
817         if (verbose) PetscPrintf(comm,"[%d]%s failed metric for coarse grid %e\n",rank,__FUNCT__,tm);
818         ierr = MatDestroy(&Prol);CHKERRQ(ierr);
819         Prol = NULL;
820       } else if (metric > .0) {
821         if (verbose) PetscPrintf(comm,"[%d]%s worst metric for coarse grid = %e\n",rank,__FUNCT__,metric);
822       }
823     } else SETERRQ(comm,PETSC_ERR_PLIB,"3D not implemented for 'geo' AMG");
824     { /* create next coords - output */
825       PetscReal *crs_crds;
826       ierr = PetscMalloc(dim*nLocalSelected*sizeof(PetscReal), &crs_crds);CHKERRQ(ierr);
827       for (kk=0; kk<nLocalSelected; kk++) { /* grab local select nodes to promote - output */
828         PetscInt lid = clid_flid[kk];
829         for (jj=0; jj<dim; jj++) crs_crds[jj*nLocalSelected + kk] = pc_gamg->data[jj*nloc + lid];
830       }
831 
832       ierr             = PetscFree(pc_gamg->data);CHKERRQ(ierr);
833       pc_gamg->data    = crs_crds; /* out */
834       pc_gamg->data_sz = dim*nLocalSelected;
835     }
836     ierr = ISDestroy(&selected_2);CHKERRQ(ierr);
837   }
838 
839   *a_P_out = Prol;  /* out */
840   ierr     = PetscFree(clid_flid);CHKERRQ(ierr);
841 #if defined PETSC_USE_LOG
842   ierr = PetscLogEventEnd(PC_GAMGProlongator_GEO,0,0,0,0);CHKERRQ(ierr);
843 #endif
844   PetscFunctionReturn(0);
845 }
846 
847 /* -------------------------------------------------------------------------- */
848 /*
849  PCCreateGAMG_GEO
850 
851   Input Parameter:
852    . pc -
853 */
854 #undef __FUNCT__
855 #define __FUNCT__ "PCCreateGAMG_GEO"
856 PetscErrorCode  PCCreateGAMG_GEO(PC pc)
857 {
858   PetscErrorCode ierr;
859   PC_MG          *mg      = (PC_MG*)pc->data;
860   PC_GAMG        *pc_gamg = (PC_GAMG*)mg->innerctx;
861 
862   PetscFunctionBegin;
863   pc->ops->setfromoptions = PCSetFromOptions_GEO;
864   /* pc->ops->destroy        = PCDestroy_GEO; */
865   /* reset does not do anything; setup not virtual */
866 
867   /* set internal function pointers */
868   pc_gamg->graph       = PCGAMGgraph_GEO;
869   pc_gamg->coarsen     = PCGAMGcoarsen_GEO;
870   pc_gamg->prolongator = PCGAMGProlongator_GEO;
871   pc_gamg->optprol     = 0;
872   pc_gamg->formkktprol = 0;
873 
874   pc_gamg->createdefaultdata = PCSetData_GEO;
875 
876   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCSetCoordinates_C","PCSetCoordinates_GEO",PCSetCoordinates_GEO);CHKERRQ(ierr);
877   PetscFunctionReturn(0);
878 }
879