xref: /petsc/src/ksp/pc/impls/bddc/bddc.c (revision e8c24aa9557c653b4f4daea7deb15bdf2bc25ad6)
1 /* TODOLIST
2 
3    Solvers
4    - Add support for cholesky for coarse solver (similar to local solvers)
5    - Propagate ksp prefixes for solvers to mat objects?
6 
7    User interface
8    - ** DM attached to pc?
9 
10    Debugging output
11    - * Better management of verbosity levels of debugging output
12 
13    Extra
14    - *** Is it possible to work with PCBDDCGraph on boundary indices only (less memory consumed)?
15    - BDDC with MG framework?
16 
17    MATIS related operations contained in BDDC code
18    - Provide general case for subassembling
19 
20 */
21 
22 #include <../src/ksp/pc/impls/bddc/bddc.h> /*I "petscpc.h" I*/  /* includes for fortran wrappers */
23 #include <../src/ksp/pc/impls/bddc/bddcprivate.h>
24 #include <petscblaslapack.h>
25 
26 static PetscBool  cited = PETSC_FALSE;
27 static const char citation[] =
28 "@article{ZampiniPCBDDC,\n"
29 "author = {Stefano Zampini},\n"
30 "title = {{PCBDDC}: A Class of Robust Dual-Primal Methods in {PETS}c},\n"
31 "journal = {SIAM Journal on Scientific Computing},\n"
32 "volume = {38},\n"
33 "number = {5},\n"
34 "pages = {S282-S306},\n"
35 "year = {2016},\n"
36 "doi = {10.1137/15M1025785},\n"
37 "URL = {http://dx.doi.org/10.1137/15M1025785},\n"
38 "eprint = {http://dx.doi.org/10.1137/15M1025785}\n"
39 "}\n";
40 
41 /* temporarily declare it */
42 PetscErrorCode PCApply_BDDC(PC,Vec,Vec);
43 
44 PetscErrorCode PCSetFromOptions_BDDC(PetscOptionItems *PetscOptionsObject,PC pc)
45 {
46   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
47   PetscErrorCode ierr;
48 
49   PetscFunctionBegin;
50   ierr = PetscOptionsHead(PetscOptionsObject,"BDDC options");CHKERRQ(ierr);
51   /* Verbose debugging */
52   ierr = PetscOptionsInt("-pc_bddc_check_level","Verbose output for PCBDDC (intended for debug)","none",pcbddc->dbg_flag,&pcbddc->dbg_flag,NULL);CHKERRQ(ierr);
53   /* Approximate solvers */
54   ierr = PetscOptionsBool("-pc_bddc_dirichlet_approximate","Inform PCBDDC that we are using approximate Dirichlet solvers","none",pcbddc->NullSpace_corr[0],&pcbddc->NullSpace_corr[0],NULL);CHKERRQ(ierr);
55   ierr = PetscOptionsBool("-pc_bddc_dirichlet_approximate_scale","Inform PCBDDC that we need to scale the Dirichlet solve","none",pcbddc->NullSpace_corr[1],&pcbddc->NullSpace_corr[1],NULL);CHKERRQ(ierr);
56   ierr = PetscOptionsBool("-pc_bddc_neumann_approximate","Inform PCBDDC that we are using approximate Neumann solvers","none",pcbddc->NullSpace_corr[2],&pcbddc->NullSpace_corr[2],NULL);CHKERRQ(ierr);
57   ierr = PetscOptionsBool("-pc_bddc_neumann_approximate_scale","Inform PCBDDC that we need to scale the Neumann solve","none",pcbddc->NullSpace_corr[3],&pcbddc->NullSpace_corr[3],NULL);CHKERRQ(ierr);
58   /* Primal space customization */
59   ierr = PetscOptionsBool("-pc_bddc_use_local_mat_graph","Use or not adjacency graph of local mat for interface analysis","none",pcbddc->use_local_adj,&pcbddc->use_local_adj,NULL);CHKERRQ(ierr);
60   ierr = PetscOptionsInt("-pc_bddc_graph_maxcount","Maximum number of shared subdomains for a connected component","none",pcbddc->graphmaxcount,&pcbddc->graphmaxcount,NULL);CHKERRQ(ierr);
61   ierr = PetscOptionsBool("-pc_bddc_use_vertices","Use or not corner dofs in coarse space","none",pcbddc->use_vertices,&pcbddc->use_vertices,NULL);CHKERRQ(ierr);
62   ierr = PetscOptionsBool("-pc_bddc_use_edges","Use or not edge constraints in coarse space","none",pcbddc->use_edges,&pcbddc->use_edges,NULL);CHKERRQ(ierr);
63   ierr = PetscOptionsBool("-pc_bddc_use_faces","Use or not face constraints in coarse space","none",pcbddc->use_faces,&pcbddc->use_faces,NULL);CHKERRQ(ierr);
64   ierr = PetscOptionsInt("-pc_bddc_vertex_size","Connected components smaller or equal to vertex size will be considered as primal vertices","none",pcbddc->vertex_size,&pcbddc->vertex_size,NULL);CHKERRQ(ierr);
65   ierr = PetscOptionsBool("-pc_bddc_use_true_nnsp","Use near null space attached to the matrix without modifications","none",pcbddc->use_nnsp_true,&pcbddc->use_nnsp_true,NULL);CHKERRQ(ierr);
66   ierr = PetscOptionsBool("-pc_bddc_use_qr_single","Use QR factorization for single constraints on cc (QR is always used when multiple constraints are present)","none",pcbddc->use_qr_single,&pcbddc->use_qr_single,NULL);CHKERRQ(ierr);
67   /* Change of basis */
68   ierr = PetscOptionsBool("-pc_bddc_use_change_of_basis","Use or not internal change of basis on local edge nodes","none",pcbddc->use_change_of_basis,&pcbddc->use_change_of_basis,NULL);CHKERRQ(ierr);
69   ierr = PetscOptionsBool("-pc_bddc_use_change_on_faces","Use or not internal change of basis on local face nodes","none",pcbddc->use_change_on_faces,&pcbddc->use_change_on_faces,NULL);CHKERRQ(ierr);
70   if (!pcbddc->use_change_of_basis) {
71     pcbddc->use_change_on_faces = PETSC_FALSE;
72   }
73   /* Switch between M_2 (default) and M_3 preconditioners (as defined by C. Dohrmann in the ref. article) */
74   ierr = PetscOptionsBool("-pc_bddc_switch_static","Switch on static condensation ops around the interface preconditioner","none",pcbddc->switch_static,&pcbddc->switch_static,NULL);CHKERRQ(ierr);
75   ierr = PetscOptionsInt("-pc_bddc_coarse_eqs_per_proc","Number of equations per process for coarse problem redistribution (significant only at the coarsest level)","none",pcbddc->coarse_eqs_per_proc,&pcbddc->coarse_eqs_per_proc,NULL);CHKERRQ(ierr);
76   ierr = PetscOptionsInt("-pc_bddc_coarsening_ratio","Set coarsening ratio used in multilevel coarsening","none",pcbddc->coarsening_ratio,&pcbddc->coarsening_ratio,NULL);CHKERRQ(ierr);
77   ierr = PetscOptionsInt("-pc_bddc_levels","Set maximum number of levels for multilevel","none",pcbddc->max_levels,&pcbddc->max_levels,NULL);CHKERRQ(ierr);
78   ierr = PetscOptionsBool("-pc_bddc_use_coarse_estimates","Use estimated eigenvalues for coarse problem","none",pcbddc->use_coarse_estimates,&pcbddc->use_coarse_estimates,NULL);CHKERRQ(ierr);
79   ierr = PetscOptionsBool("-pc_bddc_use_deluxe_scaling","Use deluxe scaling for BDDC","none",pcbddc->use_deluxe_scaling,&pcbddc->use_deluxe_scaling,NULL);CHKERRQ(ierr);
80   ierr = PetscOptionsBool("-pc_bddc_schur_rebuild","Whether or not the interface graph for Schur principal minors has to be rebuilt (i.e. define the interface without any adjacency)","none",pcbddc->sub_schurs_rebuild,&pcbddc->sub_schurs_rebuild,NULL);CHKERRQ(ierr);
81   ierr = PetscOptionsInt("-pc_bddc_schur_layers","Number of dofs' layers for the computation of principal minors (i.e. -1 uses all dofs)","none",pcbddc->sub_schurs_layers,&pcbddc->sub_schurs_layers,NULL);CHKERRQ(ierr);
82   ierr = PetscOptionsBool("-pc_bddc_schur_use_useradj","Whether or not the CSR graph specified by the user should be used for computing successive layers (default is to use adj of local mat)","none",pcbddc->sub_schurs_use_useradj,&pcbddc->sub_schurs_use_useradj,NULL);CHKERRQ(ierr);
83   ierr = PetscOptionsBool("-pc_bddc_schur_exact","Whether or not to use the exact Schur complement instead of the reduced one (which excludes size 1 cc)","none",pcbddc->sub_schurs_exact_schur,&pcbddc->sub_schurs_exact_schur,NULL);CHKERRQ(ierr);
84   ierr = PetscOptionsBool("-pc_bddc_deluxe_zerorows","Zero rows and columns of deluxe operators associated with primal dofs","none",pcbddc->deluxe_zerorows,&pcbddc->deluxe_zerorows,NULL);CHKERRQ(ierr);
85   ierr = PetscOptionsBool("-pc_bddc_deluxe_singlemat","Collapse deluxe operators","none",pcbddc->deluxe_singlemat,&pcbddc->deluxe_singlemat,NULL);CHKERRQ(ierr);
86   ierr = PetscOptionsBool("-pc_bddc_adaptive_userdefined","Use user-defined constraints (should be attached via MatSetNearNullSpace to pmat) in addition to those adaptively generated","none",pcbddc->adaptive_userdefined,&pcbddc->adaptive_userdefined,NULL);CHKERRQ(ierr);
87   ierr = PetscOptionsReal("-pc_bddc_adaptive_threshold","Threshold to be used for adaptive selection of constraints","none",pcbddc->adaptive_threshold,&pcbddc->adaptive_threshold,NULL);CHKERRQ(ierr);
88   ierr = PetscOptionsInt("-pc_bddc_adaptive_nmin","Minimum number of constraints per connected components","none",pcbddc->adaptive_nmin,&pcbddc->adaptive_nmin,NULL);CHKERRQ(ierr);
89   ierr = PetscOptionsInt("-pc_bddc_adaptive_nmax","Maximum number of constraints per connected components","none",pcbddc->adaptive_nmax,&pcbddc->adaptive_nmax,NULL);CHKERRQ(ierr);
90   ierr = PetscOptionsBool("-pc_bddc_symmetric","Symmetric computation of primal basis functions","none",pcbddc->symmetric_primal,&pcbddc->symmetric_primal,NULL);CHKERRQ(ierr);
91   ierr = PetscOptionsInt("-pc_bddc_coarse_adj","Number of processors where to map the coarse adjacency list","none",pcbddc->coarse_adj_red,&pcbddc->coarse_adj_red,NULL);CHKERRQ(ierr);
92   ierr = PetscOptionsBool("-pc_bddc_benign_trick","Apply the benign subspace trick to saddle point problems with discontinuous pressures","none",pcbddc->benign_saddle_point,&pcbddc->benign_saddle_point,NULL);CHKERRQ(ierr);
93   ierr = PetscOptionsBool("-pc_bddc_benign_change","Compute the pressure change of basis explicitly","none",pcbddc->benign_change_explicit,&pcbddc->benign_change_explicit,NULL);CHKERRQ(ierr);
94   ierr = PetscOptionsBool("-pc_bddc_benign_compute_correction","Compute the benign correction during PreSolve","none",pcbddc->benign_compute_correction,&pcbddc->benign_compute_correction,NULL);CHKERRQ(ierr);
95   ierr = PetscOptionsBool("-pc_bddc_nonetflux","Automatic computation of no-net-flux quadrature weights","none",pcbddc->compute_nonetflux,&pcbddc->compute_nonetflux,NULL);CHKERRQ(ierr);
96   ierr = PetscOptionsBool("-pc_bddc_detect_disconnected","Detects disconnected subdomains","none",pcbddc->detect_disconnected,&pcbddc->detect_disconnected,NULL);CHKERRQ(ierr);
97   ierr = PetscOptionsBool("-pc_bddc_eliminate_dirichlet","Whether or not we want to eliminate dirichlet dofs during presolve","none",pcbddc->eliminate_dirdofs,&pcbddc->eliminate_dirdofs,NULL);CHKERRQ(ierr);
98   ierr = PetscOptionsTail();CHKERRQ(ierr);
99   PetscFunctionReturn(0);
100 }
101 
102 static PetscErrorCode PCView_BDDC(PC pc,PetscViewer viewer)
103 {
104   PC_BDDC              *pcbddc = (PC_BDDC*)pc->data;
105   PC_IS                *pcis = (PC_IS*)pc->data;
106   PetscErrorCode       ierr;
107   PetscBool            isascii,isstring;
108   PetscSubcomm         subcomm;
109   PetscViewer          subviewer;
110 
111   PetscFunctionBegin;
112   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii);CHKERRQ(ierr);
113   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);CHKERRQ(ierr);
114   /* Nothing printed for the String viewer */
115   /* ASCII viewer */
116   if (isascii) {
117     PetscMPIInt   color,rank,size;
118     PetscInt64    loc[7],gsum[6],gmax[6],gmin[6],totbenign;
119     PetscScalar   interface_size;
120     PetscReal     ratio1=0.,ratio2=0.;
121     Vec           counter;
122 
123     if (!pc->setupcalled) {
124       ierr = PetscViewerASCIIPrintf(viewer,"  Partial information available: preconditioner has not been setup yet\n");CHKERRQ(ierr);
125     }
126     ierr = PetscViewerASCIIPrintf(viewer,"  Use verbose output: %D\n",pcbddc->dbg_flag);CHKERRQ(ierr);
127     ierr = PetscViewerASCIIPrintf(viewer,"  Use user-defined CSR: %d\n",!!pcbddc->mat_graph->nvtxs_csr);CHKERRQ(ierr);
128     ierr = PetscViewerASCIIPrintf(viewer,"  Use local mat graph: %d\n",pcbddc->use_local_adj && !pcbddc->mat_graph->nvtxs_csr);CHKERRQ(ierr);
129     if (pcbddc->mat_graph->twodim) {
130       ierr = PetscViewerASCIIPrintf(viewer,"  Connectivity graph topological dimension: 2\n");CHKERRQ(ierr);
131     } else {
132       ierr = PetscViewerASCIIPrintf(viewer,"  Connectivity graph topological dimension: 3\n");CHKERRQ(ierr);
133     }
134     if (pcbddc->graphmaxcount != PETSC_MAX_INT) {
135       ierr = PetscViewerASCIIPrintf(viewer,"  Graph max count: %D\n",pcbddc->graphmaxcount);CHKERRQ(ierr);
136     }
137     ierr = PetscViewerASCIIPrintf(viewer,"  Use vertices: %d (vertex size %D)\n",pcbddc->use_vertices,pcbddc->vertex_size);CHKERRQ(ierr);
138     ierr = PetscViewerASCIIPrintf(viewer,"  Use edges: %d\n",pcbddc->use_edges);CHKERRQ(ierr);
139     ierr = PetscViewerASCIIPrintf(viewer,"  Use faces: %d\n",pcbddc->use_faces);CHKERRQ(ierr);
140     ierr = PetscViewerASCIIPrintf(viewer,"  Use true near null space: %d\n",pcbddc->use_nnsp_true);CHKERRQ(ierr);
141     ierr = PetscViewerASCIIPrintf(viewer,"  Use QR for single constraints on cc: %d\n",pcbddc->use_qr_single);CHKERRQ(ierr);
142     ierr = PetscViewerASCIIPrintf(viewer,"  Use change of basis on local edge nodes: %d\n",pcbddc->use_change_of_basis);CHKERRQ(ierr);
143     ierr = PetscViewerASCIIPrintf(viewer,"  Use change of basis on local face nodes: %d\n",pcbddc->use_change_on_faces);CHKERRQ(ierr);
144     ierr = PetscViewerASCIIPrintf(viewer,"  User defined change of basis matrix: %d\n",!!pcbddc->user_ChangeOfBasisMatrix);CHKERRQ(ierr);
145     ierr = PetscViewerASCIIPrintf(viewer,"  Has change of basis matrix: %d\n",!!pcbddc->ChangeOfBasisMatrix);CHKERRQ(ierr);
146     ierr = PetscViewerASCIIPrintf(viewer,"  Eliminate dirichlet boundary dofs: %d\n",pcbddc->eliminate_dirdofs);CHKERRQ(ierr);
147     ierr = PetscViewerASCIIPrintf(viewer,"  Switch on static condensation ops around the interface preconditioner: %d\n",pcbddc->switch_static);CHKERRQ(ierr);
148     ierr = PetscViewerASCIIPrintf(viewer,"  Use exact dirichlet trick: %d\n",pcbddc->use_exact_dirichlet_trick);CHKERRQ(ierr);
149     ierr = PetscViewerASCIIPrintf(viewer,"  Multilevel max levels: %D\n",pcbddc->max_levels);CHKERRQ(ierr);
150     ierr = PetscViewerASCIIPrintf(viewer,"  Multilevel coarsening ratio: %D\n",pcbddc->coarsening_ratio);CHKERRQ(ierr);
151     ierr = PetscViewerASCIIPrintf(viewer,"  Use estimated eigs for coarse problem: %d\n",pcbddc->use_coarse_estimates);CHKERRQ(ierr);
152     ierr = PetscViewerASCIIPrintf(viewer,"  Use deluxe scaling: %d\n",pcbddc->use_deluxe_scaling);CHKERRQ(ierr);
153     ierr = PetscViewerASCIIPrintf(viewer,"  Use deluxe zerorows: %d\n",pcbddc->deluxe_zerorows);CHKERRQ(ierr);
154     ierr = PetscViewerASCIIPrintf(viewer,"  Use deluxe singlemat: %d\n",pcbddc->deluxe_singlemat);CHKERRQ(ierr);
155     ierr = PetscViewerASCIIPrintf(viewer,"  Rebuild interface graph for Schur principal minors: %d\n",pcbddc->sub_schurs_rebuild);CHKERRQ(ierr);
156     ierr = PetscViewerASCIIPrintf(viewer,"  Number of dofs' layers for the computation of principal minors: %D\n",pcbddc->sub_schurs_layers);CHKERRQ(ierr);
157     ierr = PetscViewerASCIIPrintf(viewer,"  Use user CSR graph to compute successive layers: %d\n",pcbddc->sub_schurs_use_useradj);CHKERRQ(ierr);
158     ierr = PetscViewerASCIIPrintf(viewer,"  Adaptive constraint selection threshold (active %d, userdefined %d): %g\n",pcbddc->adaptive_selection,pcbddc->adaptive_userdefined,pcbddc->adaptive_threshold);CHKERRQ(ierr);
159     ierr = PetscViewerASCIIPrintf(viewer,"  Min constraints / connected component: %D\n",pcbddc->adaptive_nmin);CHKERRQ(ierr);
160     ierr = PetscViewerASCIIPrintf(viewer,"  Max constraints / connected component: %D\n",pcbddc->adaptive_nmax);CHKERRQ(ierr);
161     ierr = PetscViewerASCIIPrintf(viewer,"  Invert exact Schur complement for adaptive selection: %d\n",pcbddc->sub_schurs_exact_schur);CHKERRQ(ierr);
162     ierr = PetscViewerASCIIPrintf(viewer,"  Symmetric computation of primal basis functions: %d\n",pcbddc->symmetric_primal);CHKERRQ(ierr);
163     ierr = PetscViewerASCIIPrintf(viewer,"  Num. Procs. to map coarse adjacency list: %D\n",pcbddc->coarse_adj_red);CHKERRQ(ierr);
164     ierr = PetscViewerASCIIPrintf(viewer,"  Coarse eqs per proc (significant at the coarsest level): %D\n",pcbddc->coarse_eqs_per_proc);CHKERRQ(ierr);
165     ierr = PetscViewerASCIIPrintf(viewer,"  Detect disconnected: %d\n",pcbddc->detect_disconnected);CHKERRQ(ierr);
166     ierr = PetscViewerASCIIPrintf(viewer,"  Benign subspace trick: %d (change explicit %d)\n",pcbddc->benign_saddle_point,pcbddc->benign_change_explicit);CHKERRQ(ierr);
167     ierr = PetscViewerASCIIPrintf(viewer,"  Benign subspace trick is active: %d\n",pcbddc->benign_have_null);CHKERRQ(ierr);
168     ierr = PetscViewerASCIIPrintf(viewer,"  Algebraic computation of no-net-flux %d\n",pcbddc->compute_nonetflux);CHKERRQ(ierr);
169     if (!pc->setupcalled) PetscFunctionReturn(0);
170 
171     /* compute interface size */
172     ierr = VecSet(pcis->vec1_B,1.0);CHKERRQ(ierr);
173     ierr = MatCreateVecs(pc->pmat,&counter,0);CHKERRQ(ierr);
174     ierr = VecSet(counter,0.0);CHKERRQ(ierr);
175     ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,counter,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
176     ierr = VecScatterEnd(pcis->global_to_B,pcis->vec1_B,counter,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
177     ierr = VecSum(counter,&interface_size);CHKERRQ(ierr);
178     ierr = VecDestroy(&counter);CHKERRQ(ierr);
179 
180     /* compute some statistics on the domain decomposition */
181     gsum[0] = 1;
182     gsum[1] = gsum[2] = gsum[3] = gsum[4] = gsum[5] = 0;
183     loc[0]  = !!pcis->n;
184     loc[1]  = pcis->n - pcis->n_B;
185     loc[2]  = pcis->n_B;
186     loc[3]  = pcbddc->local_primal_size;
187     loc[4]  = pcis->n;
188     loc[5]  = pcbddc->n_local_subs > 0 ? pcbddc->n_local_subs : (pcis->n ? 1 : 0);
189     loc[6]  = pcbddc->benign_n;
190     ierr = MPI_Reduce(loc,gsum,6,MPIU_INT64,MPI_SUM,0,PetscObjectComm((PetscObject)pc));CHKERRQ(ierr);
191     if (!loc[0]) loc[1] = loc[2] = loc[3] = loc[4] = loc[5] = -1;
192     ierr = MPI_Reduce(loc,gmax,6,MPIU_INT64,MPI_MAX,0,PetscObjectComm((PetscObject)pc));CHKERRQ(ierr);
193     if (!loc[0]) loc[1] = loc[2] = loc[3] = loc[4] = loc[5] = PETSC_MAX_INT;
194     ierr = MPI_Reduce(loc,gmin,6,MPIU_INT64,MPI_MIN,0,PetscObjectComm((PetscObject)pc));CHKERRQ(ierr);
195     ierr = MPI_Reduce(&loc[6],&totbenign,1,MPIU_INT64,MPI_SUM,0,PetscObjectComm((PetscObject)pc));CHKERRQ(ierr);
196     if (pcbddc->coarse_size) {
197       ratio1 = pc->pmat->rmap->N/(1.*pcbddc->coarse_size);
198       ratio2 = PetscRealPart(interface_size)/pcbddc->coarse_size;
199     }
200     ierr = PetscViewerASCIIPrintf(viewer,"  ********************************** STATISTICS AT LEVEL %d **********************************\n",pcbddc->current_level);CHKERRQ(ierr);
201     ierr = PetscViewerASCIIPrintf(viewer,"  Global dofs sizes: all %D interface %D coarse %D\n",pc->pmat->rmap->N,(PetscInt)PetscRealPart(interface_size),pcbddc->coarse_size);CHKERRQ(ierr);
202     ierr = PetscViewerASCIIPrintf(viewer,"  Coarsening ratios: all/coarse %D interface/coarse %D\n",(PetscInt)ratio1,(PetscInt)ratio2);CHKERRQ(ierr);
203     ierr = PetscViewerASCIIPrintf(viewer,"  Active processes : %D\n",(PetscInt)gsum[0]);CHKERRQ(ierr);
204     ierr = PetscViewerASCIIPrintf(viewer,"  Total subdomains : %D\n",(PetscInt)gsum[5]);CHKERRQ(ierr);
205     if (pcbddc->benign_have_null) {
206       ierr = PetscViewerASCIIPrintf(viewer,"  Benign subs      : %D\n",(PetscInt)totbenign);CHKERRQ(ierr);
207     }
208     ierr = PetscViewerASCIIPrintf(viewer,"  Dofs type        :\tMIN\tMAX\tMEAN\n");CHKERRQ(ierr);
209     ierr = PetscViewerASCIIPrintf(viewer,"  Interior  dofs   :\t%D\t%D\t%D\n",(PetscInt)gmin[1],(PetscInt)gmax[1],(PetscInt)(gsum[1]/gsum[0]));CHKERRQ(ierr);
210     ierr = PetscViewerASCIIPrintf(viewer,"  Interface dofs   :\t%D\t%D\t%D\n",(PetscInt)gmin[2],(PetscInt)gmax[2],(PetscInt)(gsum[2]/gsum[0]));CHKERRQ(ierr);
211     ierr = PetscViewerASCIIPrintf(viewer,"  Primal    dofs   :\t%D\t%D\t%D\n",(PetscInt)gmin[3],(PetscInt)gmax[3],(PetscInt)(gsum[3]/gsum[0]));CHKERRQ(ierr);
212     ierr = PetscViewerASCIIPrintf(viewer,"  Local     dofs   :\t%D\t%D\t%D\n",(PetscInt)gmin[4],(PetscInt)gmax[4],(PetscInt)(gsum[4]/gsum[0]));CHKERRQ(ierr);
213     ierr = PetscViewerASCIIPrintf(viewer,"  Local     subs   :\t%D\t%D\n"    ,(PetscInt)gmin[5],(PetscInt)gmax[5]);CHKERRQ(ierr);
214     ierr = PetscViewerASCIIPrintf(viewer,"  ********************************** COARSE PROBLEM DETAILS *********************************\n");CHKERRQ(ierr);
215     ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
216 
217     /* the coarse problem can be handled by a different communicator */
218     if (pcbddc->coarse_ksp) color = 1;
219     else color = 0;
220     ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)pc),&rank);CHKERRQ(ierr);
221     ierr = MPI_Comm_size(PetscObjectComm((PetscObject)pc),&size);CHKERRQ(ierr);
222     ierr = PetscSubcommCreate(PetscObjectComm((PetscObject)pc),&subcomm);CHKERRQ(ierr);
223     ierr = PetscSubcommSetNumber(subcomm,PetscMin(size,2));CHKERRQ(ierr);
224     ierr = PetscSubcommSetTypeGeneral(subcomm,color,rank);CHKERRQ(ierr);
225     ierr = PetscViewerGetSubViewer(viewer,PetscSubcommChild(subcomm),&subviewer);CHKERRQ(ierr);
226     if (color == 1) {
227       ierr = KSPView(pcbddc->coarse_ksp,subviewer);CHKERRQ(ierr);
228       ierr = PetscViewerFlush(subviewer);CHKERRQ(ierr);
229     }
230     ierr = PetscViewerRestoreSubViewer(viewer,PetscSubcommChild(subcomm),&subviewer);CHKERRQ(ierr);
231     ierr = PetscSubcommDestroy(&subcomm);CHKERRQ(ierr);
232     ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
233   }
234   PetscFunctionReturn(0);
235 }
236 
237 static PetscErrorCode PCBDDCSetDiscreteGradient_BDDC(PC pc, Mat G, PetscInt order, PetscInt field, PetscBool global, PetscBool conforming)
238 {
239   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
240   PetscErrorCode ierr;
241 
242   PetscFunctionBegin;
243   ierr = PetscObjectReference((PetscObject)G);CHKERRQ(ierr);
244   ierr = MatDestroy(&pcbddc->discretegradient);CHKERRQ(ierr);
245   pcbddc->discretegradient = G;
246   pcbddc->nedorder         = order > 0 ? order : -order;
247   pcbddc->nedfield         = field;
248   pcbddc->nedglobal        = global;
249   pcbddc->conforming       = conforming;
250   PetscFunctionReturn(0);
251 }
252 
253 /*@
254  PCBDDCSetDiscreteGradient - Sets the discrete gradient
255 
256    Collective on PC
257 
258    Input Parameters:
259 +  pc         - the preconditioning context
260 .  G          - the discrete gradient matrix (should be in AIJ format)
261 .  order      - the order of the Nedelec space (1 for the lowest order)
262 .  field      - the field id of the Nedelec dofs (not used if the fields have not been specified)
263 .  global     - the type of global ordering for the rows of G
264 -  conforming - whether the mesh is conforming or not
265 
266    Level: advanced
267 
268    Notes: The discrete gradient matrix G is used to analyze the subdomain edges, and it should not contain any zero entry.
269           For variable order spaces, the order should be set to zero.
270           If global is true, the rows of G should be given in global ordering for the whole dofs;
271           if false, the ordering should be global for the Nedelec field.
272           In the latter case, it should hold gid[i] < gid[j] iff geid[i] < geid[j], with gid the global orderding for all the dofs
273           and geid the one for the Nedelec field.
274 
275 .seealso: PCBDDC,PCBDDCSetDofsSplitting(),PCBDDCSetDofsSplittingLocal()
276 @*/
277 PetscErrorCode PCBDDCSetDiscreteGradient(PC pc, Mat G, PetscInt order, PetscInt field, PetscBool global, PetscBool conforming)
278 {
279   PetscErrorCode ierr;
280 
281   PetscFunctionBegin;
282   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
283   PetscValidHeaderSpecific(G,MAT_CLASSID,2);
284   PetscValidLogicalCollectiveInt(pc,order,3);
285   PetscValidLogicalCollectiveInt(pc,field,4);
286   PetscValidLogicalCollectiveBool(pc,global,5);
287   PetscValidLogicalCollectiveBool(pc,conforming,6);
288   PetscCheckSameComm(pc,1,G,2);
289   ierr = PetscTryMethod(pc,"PCBDDCSetDiscreteGradient_C",(PC,Mat,PetscInt,PetscInt,PetscBool,PetscBool),(pc,G,order,field,global,conforming));CHKERRQ(ierr);
290   PetscFunctionReturn(0);
291 }
292 
293 static PetscErrorCode PCBDDCSetDivergenceMat_BDDC(PC pc, Mat divudotp, PetscBool trans, IS vl2l)
294 {
295   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
296   PetscErrorCode ierr;
297 
298   PetscFunctionBegin;
299   ierr = PetscObjectReference((PetscObject)divudotp);CHKERRQ(ierr);
300   ierr = MatDestroy(&pcbddc->divudotp);CHKERRQ(ierr);
301   pcbddc->divudotp = divudotp;
302   pcbddc->divudotp_trans = trans;
303   pcbddc->compute_nonetflux = PETSC_TRUE;
304   if (vl2l) {
305     ierr = PetscObjectReference((PetscObject)vl2l);CHKERRQ(ierr);
306     ierr = ISDestroy(&pcbddc->divudotp_vl2l);CHKERRQ(ierr);
307     pcbddc->divudotp_vl2l = vl2l;
308   }
309   PetscFunctionReturn(0);
310 }
311 
312 /*@
313  PCBDDCSetDivergenceMat - Sets the linear operator representing \int_\Omega \div {\bf u} \cdot p dx
314 
315    Collective on PC
316 
317    Input Parameters:
318 +  pc - the preconditioning context
319 .  divudotp - the matrix (must be of type MATIS)
320 .  trans - if trans if false (resp. true), then pressures are in the test (trial) space and velocities are in the trial (test) space.
321 -  vl2l - optional IS describing the local (wrt the local mat in divudotp) to local (wrt the local mat in pc->pmat) map for the velocities
322 
323    Level: advanced
324 
325    Notes: This auxiliary matrix is used to compute quadrature weights representing the net-flux across subdomain boundaries
326 
327 .seealso: PCBDDC
328 @*/
329 PetscErrorCode PCBDDCSetDivergenceMat(PC pc, Mat divudotp, PetscBool trans, IS vl2l)
330 {
331   PetscBool      ismatis;
332   PetscErrorCode ierr;
333 
334   PetscFunctionBegin;
335   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
336   PetscValidHeaderSpecific(divudotp,MAT_CLASSID,2);
337   PetscCheckSameComm(pc,1,divudotp,2);
338   PetscValidLogicalCollectiveBool(pc,trans,3);
339   if (vl2l) PetscValidHeaderSpecific(divudotp,IS_CLASSID,4);
340   ierr = PetscObjectTypeCompare((PetscObject)divudotp,MATIS,&ismatis);CHKERRQ(ierr);
341   if (!ismatis) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_ARG_WRONG,"Divergence matrix needs to be of type MATIS");
342   ierr = PetscTryMethod(pc,"PCBDDCSetDivergenceMat_C",(PC,Mat,PetscBool,IS),(pc,divudotp,trans,vl2l));CHKERRQ(ierr);
343   PetscFunctionReturn(0);
344 }
345 
346 static PetscErrorCode PCBDDCSetChangeOfBasisMat_BDDC(PC pc, Mat change, PetscBool interior)
347 {
348   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
349   PetscErrorCode ierr;
350 
351   PetscFunctionBegin;
352   ierr = PetscObjectReference((PetscObject)change);CHKERRQ(ierr);
353   ierr = MatDestroy(&pcbddc->user_ChangeOfBasisMatrix);CHKERRQ(ierr);
354   pcbddc->user_ChangeOfBasisMatrix = change;
355   pcbddc->change_interior = interior;
356   PetscFunctionReturn(0);
357 }
358 /*@
359  PCBDDCSetChangeOfBasisMat - Set user defined change of basis for dofs
360 
361    Collective on PC
362 
363    Input Parameters:
364 +  pc - the preconditioning context
365 .  change - the change of basis matrix
366 -  interior - whether or not the change of basis modifies interior dofs
367 
368    Level: intermediate
369 
370    Notes:
371 
372 .seealso: PCBDDC
373 @*/
374 PetscErrorCode PCBDDCSetChangeOfBasisMat(PC pc, Mat change, PetscBool interior)
375 {
376   PetscErrorCode ierr;
377 
378   PetscFunctionBegin;
379   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
380   PetscValidHeaderSpecific(change,MAT_CLASSID,2);
381   PetscCheckSameComm(pc,1,change,2);
382   if (pc->mat) {
383     PetscInt rows_c,cols_c,rows,cols;
384     ierr = MatGetSize(pc->mat,&rows,&cols);CHKERRQ(ierr);
385     ierr = MatGetSize(change,&rows_c,&cols_c);CHKERRQ(ierr);
386     if (rows_c != rows) SETERRQ2(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Invalid number of rows for change of basis matrix! %D != %D",rows_c,rows);
387     if (cols_c != cols) SETERRQ2(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Invalid number of columns for change of basis matrix! %D != %D",cols_c,cols);
388     ierr = MatGetLocalSize(pc->mat,&rows,&cols);CHKERRQ(ierr);
389     ierr = MatGetLocalSize(change,&rows_c,&cols_c);CHKERRQ(ierr);
390     if (rows_c != rows) SETERRQ2(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Invalid number of local rows for change of basis matrix! %D != %D",rows_c,rows);
391     if (cols_c != cols) SETERRQ2(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Invalid number of local columns for change of basis matrix! %D != %D",cols_c,cols);
392   }
393   ierr = PetscTryMethod(pc,"PCBDDCSetChangeOfBasisMat_C",(PC,Mat,PetscBool),(pc,change,interior));CHKERRQ(ierr);
394   PetscFunctionReturn(0);
395 }
396 
397 static PetscErrorCode PCBDDCSetPrimalVerticesIS_BDDC(PC pc, IS PrimalVertices)
398 {
399   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
400   PetscBool      isequal = PETSC_FALSE;
401   PetscErrorCode ierr;
402 
403   PetscFunctionBegin;
404   ierr = PetscObjectReference((PetscObject)PrimalVertices);CHKERRQ(ierr);
405   if (pcbddc->user_primal_vertices) {
406     ierr = ISEqual(PrimalVertices,pcbddc->user_primal_vertices,&isequal);CHKERRQ(ierr);
407   }
408   ierr = ISDestroy(&pcbddc->user_primal_vertices);CHKERRQ(ierr);
409   ierr = ISDestroy(&pcbddc->user_primal_vertices_local);CHKERRQ(ierr);
410   pcbddc->user_primal_vertices = PrimalVertices;
411   if (!isequal) pcbddc->recompute_topography = PETSC_TRUE;
412   PetscFunctionReturn(0);
413 }
414 /*@
415  PCBDDCSetPrimalVerticesIS - Set additional user defined primal vertices in PCBDDC
416 
417    Collective
418 
419    Input Parameters:
420 +  pc - the preconditioning context
421 -  PrimalVertices - index set of primal vertices in global numbering (can be empty)
422 
423    Level: intermediate
424 
425    Notes:
426      Any process can list any global node
427 
428 .seealso: PCBDDC
429 @*/
430 PetscErrorCode PCBDDCSetPrimalVerticesIS(PC pc, IS PrimalVertices)
431 {
432   PetscErrorCode ierr;
433 
434   PetscFunctionBegin;
435   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
436   PetscValidHeaderSpecific(PrimalVertices,IS_CLASSID,2);
437   PetscCheckSameComm(pc,1,PrimalVertices,2);
438   ierr = PetscTryMethod(pc,"PCBDDCSetPrimalVerticesIS_C",(PC,IS),(pc,PrimalVertices));CHKERRQ(ierr);
439   PetscFunctionReturn(0);
440 }
441 
442 static PetscErrorCode PCBDDCSetPrimalVerticesLocalIS_BDDC(PC pc, IS PrimalVertices)
443 {
444   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
445   PetscBool      isequal = PETSC_FALSE;
446   PetscErrorCode ierr;
447 
448   PetscFunctionBegin;
449   ierr = PetscObjectReference((PetscObject)PrimalVertices);CHKERRQ(ierr);
450   if (pcbddc->user_primal_vertices_local) {
451     ierr = ISEqual(PrimalVertices,pcbddc->user_primal_vertices_local,&isequal);CHKERRQ(ierr);
452   }
453   ierr = ISDestroy(&pcbddc->user_primal_vertices);CHKERRQ(ierr);
454   ierr = ISDestroy(&pcbddc->user_primal_vertices_local);CHKERRQ(ierr);
455   pcbddc->user_primal_vertices_local = PrimalVertices;
456   if (!isequal) pcbddc->recompute_topography = PETSC_TRUE;
457   PetscFunctionReturn(0);
458 }
459 /*@
460  PCBDDCSetPrimalVerticesLocalIS - Set additional user defined primal vertices in PCBDDC
461 
462    Collective
463 
464    Input Parameters:
465 +  pc - the preconditioning context
466 -  PrimalVertices - index set of primal vertices in local numbering (can be empty)
467 
468    Level: intermediate
469 
470    Notes:
471 
472 .seealso: PCBDDC
473 @*/
474 PetscErrorCode PCBDDCSetPrimalVerticesLocalIS(PC pc, IS PrimalVertices)
475 {
476   PetscErrorCode ierr;
477 
478   PetscFunctionBegin;
479   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
480   PetscValidHeaderSpecific(PrimalVertices,IS_CLASSID,2);
481   PetscCheckSameComm(pc,1,PrimalVertices,2);
482   ierr = PetscTryMethod(pc,"PCBDDCSetPrimalVerticesLocalIS_C",(PC,IS),(pc,PrimalVertices));CHKERRQ(ierr);
483   PetscFunctionReturn(0);
484 }
485 
486 static PetscErrorCode PCBDDCSetCoarseningRatio_BDDC(PC pc,PetscInt k)
487 {
488   PC_BDDC  *pcbddc = (PC_BDDC*)pc->data;
489 
490   PetscFunctionBegin;
491   pcbddc->coarsening_ratio = k;
492   PetscFunctionReturn(0);
493 }
494 
495 /*@
496  PCBDDCSetCoarseningRatio - Set coarsening ratio used in multilevel
497 
498    Logically collective on PC
499 
500    Input Parameters:
501 +  pc - the preconditioning context
502 -  k - coarsening ratio (H/h at the coarser level)
503 
504    Options Database Keys:
505 .    -pc_bddc_coarsening_ratio
506 
507    Level: intermediate
508 
509    Notes:
510      Approximatively k subdomains at the finer level will be aggregated into a single subdomain at the coarser level
511 
512 .seealso: PCBDDC, PCBDDCSetLevels()
513 @*/
514 PetscErrorCode PCBDDCSetCoarseningRatio(PC pc,PetscInt k)
515 {
516   PetscErrorCode ierr;
517 
518   PetscFunctionBegin;
519   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
520   PetscValidLogicalCollectiveInt(pc,k,2);
521   ierr = PetscTryMethod(pc,"PCBDDCSetCoarseningRatio_C",(PC,PetscInt),(pc,k));CHKERRQ(ierr);
522   PetscFunctionReturn(0);
523 }
524 
525 /* The following functions (PCBDDCSetUseExactDirichlet PCBDDCSetLevel) are not public */
526 static PetscErrorCode PCBDDCSetUseExactDirichlet_BDDC(PC pc,PetscBool flg)
527 {
528   PC_BDDC  *pcbddc = (PC_BDDC*)pc->data;
529 
530   PetscFunctionBegin;
531   pcbddc->use_exact_dirichlet_trick = flg;
532   PetscFunctionReturn(0);
533 }
534 
535 PetscErrorCode PCBDDCSetUseExactDirichlet(PC pc,PetscBool flg)
536 {
537   PetscErrorCode ierr;
538 
539   PetscFunctionBegin;
540   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
541   PetscValidLogicalCollectiveBool(pc,flg,2);
542   ierr = PetscTryMethod(pc,"PCBDDCSetUseExactDirichlet_C",(PC,PetscBool),(pc,flg));CHKERRQ(ierr);
543   PetscFunctionReturn(0);
544 }
545 
546 static PetscErrorCode PCBDDCSetLevel_BDDC(PC pc,PetscInt level)
547 {
548   PC_BDDC  *pcbddc = (PC_BDDC*)pc->data;
549 
550   PetscFunctionBegin;
551   pcbddc->current_level = level;
552   PetscFunctionReturn(0);
553 }
554 
555 PetscErrorCode PCBDDCSetLevel(PC pc,PetscInt level)
556 {
557   PetscErrorCode ierr;
558 
559   PetscFunctionBegin;
560   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
561   PetscValidLogicalCollectiveInt(pc,level,2);
562   ierr = PetscTryMethod(pc,"PCBDDCSetLevel_C",(PC,PetscInt),(pc,level));CHKERRQ(ierr);
563   PetscFunctionReturn(0);
564 }
565 
566 static PetscErrorCode PCBDDCSetLevels_BDDC(PC pc,PetscInt levels)
567 {
568   PC_BDDC  *pcbddc = (PC_BDDC*)pc->data;
569 
570   PetscFunctionBegin;
571   pcbddc->max_levels = levels;
572   PetscFunctionReturn(0);
573 }
574 
575 /*@
576  PCBDDCSetLevels - Sets the maximum number of levels for multilevel
577 
578    Logically collective on PC
579 
580    Input Parameters:
581 +  pc - the preconditioning context
582 -  levels - the maximum number of levels (max 9)
583 
584    Options Database Keys:
585 .    -pc_bddc_levels
586 
587    Level: intermediate
588 
589    Notes:
590      Default value is 0, i.e. traditional one-level BDDC
591 
592 .seealso: PCBDDC, PCBDDCSetCoarseningRatio()
593 @*/
594 PetscErrorCode PCBDDCSetLevels(PC pc,PetscInt levels)
595 {
596   PetscErrorCode ierr;
597 
598   PetscFunctionBegin;
599   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
600   PetscValidLogicalCollectiveInt(pc,levels,2);
601   if (levels > 99) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Maximum number of levels for bddc is 99\n");
602   ierr = PetscTryMethod(pc,"PCBDDCSetLevels_C",(PC,PetscInt),(pc,levels));CHKERRQ(ierr);
603   PetscFunctionReturn(0);
604 }
605 
606 static PetscErrorCode PCBDDCSetDirichletBoundaries_BDDC(PC pc,IS DirichletBoundaries)
607 {
608   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
609   PetscBool      isequal = PETSC_FALSE;
610   PetscErrorCode ierr;
611 
612   PetscFunctionBegin;
613   ierr = PetscObjectReference((PetscObject)DirichletBoundaries);CHKERRQ(ierr);
614   if (pcbddc->DirichletBoundaries) {
615     ierr = ISEqual(DirichletBoundaries,pcbddc->DirichletBoundaries,&isequal);CHKERRQ(ierr);
616   }
617   /* last user setting takes precendence -> destroy any other customization */
618   ierr = ISDestroy(&pcbddc->DirichletBoundariesLocal);CHKERRQ(ierr);
619   ierr = ISDestroy(&pcbddc->DirichletBoundaries);CHKERRQ(ierr);
620   pcbddc->DirichletBoundaries = DirichletBoundaries;
621   if (!isequal) pcbddc->recompute_topography = PETSC_TRUE;
622   PetscFunctionReturn(0);
623 }
624 
625 /*@
626  PCBDDCSetDirichletBoundaries - Set IS defining Dirichlet boundaries for the global problem.
627 
628    Collective
629 
630    Input Parameters:
631 +  pc - the preconditioning context
632 -  DirichletBoundaries - parallel IS defining the Dirichlet boundaries
633 
634    Level: intermediate
635 
636    Notes:
637      Provide the information if you used MatZeroRows/Columns routines. Any process can list any global node
638 
639 .seealso: PCBDDC, PCBDDCSetDirichletBoundariesLocal(), MatZeroRows(), MatZeroRowsColumns()
640 @*/
641 PetscErrorCode PCBDDCSetDirichletBoundaries(PC pc,IS DirichletBoundaries)
642 {
643   PetscErrorCode ierr;
644 
645   PetscFunctionBegin;
646   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
647   PetscValidHeaderSpecific(DirichletBoundaries,IS_CLASSID,2);
648   PetscCheckSameComm(pc,1,DirichletBoundaries,2);
649   ierr = PetscTryMethod(pc,"PCBDDCSetDirichletBoundaries_C",(PC,IS),(pc,DirichletBoundaries));CHKERRQ(ierr);
650   PetscFunctionReturn(0);
651 }
652 
653 static PetscErrorCode PCBDDCSetDirichletBoundariesLocal_BDDC(PC pc,IS DirichletBoundaries)
654 {
655   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
656   PetscBool      isequal = PETSC_FALSE;
657   PetscErrorCode ierr;
658 
659   PetscFunctionBegin;
660   ierr = PetscObjectReference((PetscObject)DirichletBoundaries);CHKERRQ(ierr);
661   if (pcbddc->DirichletBoundariesLocal) {
662     ierr = ISEqual(DirichletBoundaries,pcbddc->DirichletBoundariesLocal,&isequal);CHKERRQ(ierr);
663   }
664   /* last user setting takes precendence -> destroy any other customization */
665   ierr = ISDestroy(&pcbddc->DirichletBoundariesLocal);CHKERRQ(ierr);
666   ierr = ISDestroy(&pcbddc->DirichletBoundaries);CHKERRQ(ierr);
667   pcbddc->DirichletBoundariesLocal = DirichletBoundaries;
668   if (!isequal) pcbddc->recompute_topography = PETSC_TRUE;
669   PetscFunctionReturn(0);
670 }
671 
672 /*@
673  PCBDDCSetDirichletBoundariesLocal - Set IS defining Dirichlet boundaries for the global problem in local ordering.
674 
675    Collective
676 
677    Input Parameters:
678 +  pc - the preconditioning context
679 -  DirichletBoundaries - parallel IS defining the Dirichlet boundaries (in local ordering)
680 
681    Level: intermediate
682 
683    Notes:
684 
685 .seealso: PCBDDC, PCBDDCSetDirichletBoundaries(), MatZeroRows(), MatZeroRowsColumns()
686 @*/
687 PetscErrorCode PCBDDCSetDirichletBoundariesLocal(PC pc,IS DirichletBoundaries)
688 {
689   PetscErrorCode ierr;
690 
691   PetscFunctionBegin;
692   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
693   PetscValidHeaderSpecific(DirichletBoundaries,IS_CLASSID,2);
694   PetscCheckSameComm(pc,1,DirichletBoundaries,2);
695   ierr = PetscTryMethod(pc,"PCBDDCSetDirichletBoundariesLocal_C",(PC,IS),(pc,DirichletBoundaries));CHKERRQ(ierr);
696   PetscFunctionReturn(0);
697 }
698 
699 static PetscErrorCode PCBDDCSetNeumannBoundaries_BDDC(PC pc,IS NeumannBoundaries)
700 {
701   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
702   PetscBool      isequal = PETSC_FALSE;
703   PetscErrorCode ierr;
704 
705   PetscFunctionBegin;
706   ierr = PetscObjectReference((PetscObject)NeumannBoundaries);CHKERRQ(ierr);
707   if (pcbddc->NeumannBoundaries) {
708     ierr = ISEqual(NeumannBoundaries,pcbddc->NeumannBoundaries,&isequal);CHKERRQ(ierr);
709   }
710   /* last user setting takes precendence -> destroy any other customization */
711   ierr = ISDestroy(&pcbddc->NeumannBoundariesLocal);CHKERRQ(ierr);
712   ierr = ISDestroy(&pcbddc->NeumannBoundaries);CHKERRQ(ierr);
713   pcbddc->NeumannBoundaries = NeumannBoundaries;
714   if (!isequal) pcbddc->recompute_topography = PETSC_TRUE;
715   PetscFunctionReturn(0);
716 }
717 
718 /*@
719  PCBDDCSetNeumannBoundaries - Set IS defining Neumann boundaries for the global problem.
720 
721    Collective
722 
723    Input Parameters:
724 +  pc - the preconditioning context
725 -  NeumannBoundaries - parallel IS defining the Neumann boundaries
726 
727    Level: intermediate
728 
729    Notes:
730      Any process can list any global node
731 
732 .seealso: PCBDDC, PCBDDCSetNeumannBoundariesLocal()
733 @*/
734 PetscErrorCode PCBDDCSetNeumannBoundaries(PC pc,IS NeumannBoundaries)
735 {
736   PetscErrorCode ierr;
737 
738   PetscFunctionBegin;
739   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
740   PetscValidHeaderSpecific(NeumannBoundaries,IS_CLASSID,2);
741   PetscCheckSameComm(pc,1,NeumannBoundaries,2);
742   ierr = PetscTryMethod(pc,"PCBDDCSetNeumannBoundaries_C",(PC,IS),(pc,NeumannBoundaries));CHKERRQ(ierr);
743   PetscFunctionReturn(0);
744 }
745 
746 static PetscErrorCode PCBDDCSetNeumannBoundariesLocal_BDDC(PC pc,IS NeumannBoundaries)
747 {
748   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
749   PetscBool      isequal = PETSC_FALSE;
750   PetscErrorCode ierr;
751 
752   PetscFunctionBegin;
753   ierr = PetscObjectReference((PetscObject)NeumannBoundaries);CHKERRQ(ierr);
754   if (pcbddc->NeumannBoundariesLocal) {
755     ierr = ISEqual(NeumannBoundaries,pcbddc->NeumannBoundariesLocal,&isequal);CHKERRQ(ierr);
756   }
757   /* last user setting takes precendence -> destroy any other customization */
758   ierr = ISDestroy(&pcbddc->NeumannBoundariesLocal);CHKERRQ(ierr);
759   ierr = ISDestroy(&pcbddc->NeumannBoundaries);CHKERRQ(ierr);
760   pcbddc->NeumannBoundariesLocal = NeumannBoundaries;
761   if (!isequal) pcbddc->recompute_topography = PETSC_TRUE;
762   PetscFunctionReturn(0);
763 }
764 
765 /*@
766  PCBDDCSetNeumannBoundariesLocal - Set IS defining Neumann boundaries for the global problem in local ordering.
767 
768    Collective
769 
770    Input Parameters:
771 +  pc - the preconditioning context
772 -  NeumannBoundaries - parallel IS defining the subdomain part of Neumann boundaries (in local ordering)
773 
774    Level: intermediate
775 
776    Notes:
777 
778 .seealso: PCBDDC, PCBDDCSetNeumannBoundaries()
779 @*/
780 PetscErrorCode PCBDDCSetNeumannBoundariesLocal(PC pc,IS NeumannBoundaries)
781 {
782   PetscErrorCode ierr;
783 
784   PetscFunctionBegin;
785   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
786   PetscValidHeaderSpecific(NeumannBoundaries,IS_CLASSID,2);
787   PetscCheckSameComm(pc,1,NeumannBoundaries,2);
788   ierr = PetscTryMethod(pc,"PCBDDCSetNeumannBoundariesLocal_C",(PC,IS),(pc,NeumannBoundaries));CHKERRQ(ierr);
789   PetscFunctionReturn(0);
790 }
791 
792 static PetscErrorCode PCBDDCGetDirichletBoundaries_BDDC(PC pc,IS *DirichletBoundaries)
793 {
794   PC_BDDC  *pcbddc = (PC_BDDC*)pc->data;
795 
796   PetscFunctionBegin;
797   *DirichletBoundaries = pcbddc->DirichletBoundaries;
798   PetscFunctionReturn(0);
799 }
800 
801 /*@
802  PCBDDCGetDirichletBoundaries - Get parallel IS for Dirichlet boundaries
803 
804    Collective
805 
806    Input Parameters:
807 .  pc - the preconditioning context
808 
809    Output Parameters:
810 .  DirichletBoundaries - index set defining the Dirichlet boundaries
811 
812    Level: intermediate
813 
814    Notes:
815      The IS returned (if any) is the same passed in earlier by the user with PCBDDCSetDirichletBoundaries
816 
817 .seealso: PCBDDC
818 @*/
819 PetscErrorCode PCBDDCGetDirichletBoundaries(PC pc,IS *DirichletBoundaries)
820 {
821   PetscErrorCode ierr;
822 
823   PetscFunctionBegin;
824   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
825   ierr = PetscUseMethod(pc,"PCBDDCGetDirichletBoundaries_C",(PC,IS*),(pc,DirichletBoundaries));CHKERRQ(ierr);
826   PetscFunctionReturn(0);
827 }
828 
829 static PetscErrorCode PCBDDCGetDirichletBoundariesLocal_BDDC(PC pc,IS *DirichletBoundaries)
830 {
831   PC_BDDC  *pcbddc = (PC_BDDC*)pc->data;
832 
833   PetscFunctionBegin;
834   *DirichletBoundaries = pcbddc->DirichletBoundariesLocal;
835   PetscFunctionReturn(0);
836 }
837 
838 /*@
839  PCBDDCGetDirichletBoundariesLocal - Get parallel IS for Dirichlet boundaries (in local ordering)
840 
841    Collective
842 
843    Input Parameters:
844 .  pc - the preconditioning context
845 
846    Output Parameters:
847 .  DirichletBoundaries - index set defining the subdomain part of Dirichlet boundaries
848 
849    Level: intermediate
850 
851    Notes:
852      The IS returned could be the same passed in earlier by the user (if provided with PCBDDCSetDirichletBoundariesLocal) or a global-to-local map of the global IS (if provided with PCBDDCSetDirichletBoundaries).
853           In the latter case, the IS will be available after PCSetUp.
854 
855 .seealso: PCBDDC
856 @*/
857 PetscErrorCode PCBDDCGetDirichletBoundariesLocal(PC pc,IS *DirichletBoundaries)
858 {
859   PetscErrorCode ierr;
860 
861   PetscFunctionBegin;
862   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
863   ierr = PetscUseMethod(pc,"PCBDDCGetDirichletBoundariesLocal_C",(PC,IS*),(pc,DirichletBoundaries));CHKERRQ(ierr);
864   PetscFunctionReturn(0);
865 }
866 
867 static PetscErrorCode PCBDDCGetNeumannBoundaries_BDDC(PC pc,IS *NeumannBoundaries)
868 {
869   PC_BDDC  *pcbddc = (PC_BDDC*)pc->data;
870 
871   PetscFunctionBegin;
872   *NeumannBoundaries = pcbddc->NeumannBoundaries;
873   PetscFunctionReturn(0);
874 }
875 
876 /*@
877  PCBDDCGetNeumannBoundaries - Get parallel IS for Neumann boundaries
878 
879    Collective
880 
881    Input Parameters:
882 .  pc - the preconditioning context
883 
884    Output Parameters:
885 .  NeumannBoundaries - index set defining the Neumann boundaries
886 
887    Level: intermediate
888 
889    Notes:
890      The IS returned (if any) is the same passed in earlier by the user with PCBDDCSetNeumannBoundaries
891 
892 .seealso: PCBDDC
893 @*/
894 PetscErrorCode PCBDDCGetNeumannBoundaries(PC pc,IS *NeumannBoundaries)
895 {
896   PetscErrorCode ierr;
897 
898   PetscFunctionBegin;
899   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
900   ierr = PetscUseMethod(pc,"PCBDDCGetNeumannBoundaries_C",(PC,IS*),(pc,NeumannBoundaries));CHKERRQ(ierr);
901   PetscFunctionReturn(0);
902 }
903 
904 static PetscErrorCode PCBDDCGetNeumannBoundariesLocal_BDDC(PC pc,IS *NeumannBoundaries)
905 {
906   PC_BDDC  *pcbddc = (PC_BDDC*)pc->data;
907 
908   PetscFunctionBegin;
909   *NeumannBoundaries = pcbddc->NeumannBoundariesLocal;
910   PetscFunctionReturn(0);
911 }
912 
913 /*@
914  PCBDDCGetNeumannBoundariesLocal - Get parallel IS for Neumann boundaries (in local ordering)
915 
916    Collective
917 
918    Input Parameters:
919 .  pc - the preconditioning context
920 
921    Output Parameters:
922 .  NeumannBoundaries - index set defining the subdomain part of Neumann boundaries
923 
924    Level: intermediate
925 
926    Notes:
927      The IS returned could be the same passed in earlier by the user (if provided with PCBDDCSetNeumannBoundariesLocal) or a global-to-local map of the global IS (if provided with PCBDDCSetNeumannBoundaries).
928           In the latter case, the IS will be available after PCSetUp.
929 
930 .seealso: PCBDDC
931 @*/
932 PetscErrorCode PCBDDCGetNeumannBoundariesLocal(PC pc,IS *NeumannBoundaries)
933 {
934   PetscErrorCode ierr;
935 
936   PetscFunctionBegin;
937   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
938   ierr = PetscUseMethod(pc,"PCBDDCGetNeumannBoundariesLocal_C",(PC,IS*),(pc,NeumannBoundaries));CHKERRQ(ierr);
939   PetscFunctionReturn(0);
940 }
941 
942 static PetscErrorCode PCBDDCSetLocalAdjacencyGraph_BDDC(PC pc, PetscInt nvtxs,const PetscInt xadj[],const PetscInt adjncy[], PetscCopyMode copymode)
943 {
944   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
945   PCBDDCGraph    mat_graph = pcbddc->mat_graph;
946   PetscBool      same_data = PETSC_FALSE;
947   PetscErrorCode ierr;
948 
949   PetscFunctionBegin;
950   if (!nvtxs) {
951     if (copymode == PETSC_OWN_POINTER) {
952       ierr = PetscFree(xadj);CHKERRQ(ierr);
953       ierr = PetscFree(adjncy);CHKERRQ(ierr);
954     }
955     ierr = PCBDDCGraphResetCSR(mat_graph);CHKERRQ(ierr);
956     PetscFunctionReturn(0);
957   }
958   if (mat_graph->nvtxs == nvtxs && mat_graph->freecsr) { /* we own the data */
959     if (mat_graph->xadj == xadj && mat_graph->adjncy == adjncy) same_data = PETSC_TRUE;
960     if (!same_data && mat_graph->xadj[nvtxs] == xadj[nvtxs]) {
961       ierr = PetscMemcmp(xadj,mat_graph->xadj,(nvtxs+1)*sizeof(PetscInt),&same_data);CHKERRQ(ierr);
962       if (same_data) {
963         ierr = PetscMemcmp(adjncy,mat_graph->adjncy,xadj[nvtxs]*sizeof(PetscInt),&same_data);CHKERRQ(ierr);
964       }
965     }
966   }
967   if (!same_data) {
968     /* free old CSR */
969     ierr = PCBDDCGraphResetCSR(mat_graph);CHKERRQ(ierr);
970     /* get CSR into graph structure */
971     if (copymode == PETSC_COPY_VALUES) {
972       ierr = PetscMalloc1(nvtxs+1,&mat_graph->xadj);CHKERRQ(ierr);
973       ierr = PetscMalloc1(xadj[nvtxs],&mat_graph->adjncy);CHKERRQ(ierr);
974       ierr = PetscMemcpy(mat_graph->xadj,xadj,(nvtxs+1)*sizeof(PetscInt));CHKERRQ(ierr);
975       ierr = PetscMemcpy(mat_graph->adjncy,adjncy,xadj[nvtxs]*sizeof(PetscInt));CHKERRQ(ierr);
976       mat_graph->freecsr = PETSC_TRUE;
977     } else if (copymode == PETSC_OWN_POINTER) {
978       mat_graph->xadj    = (PetscInt*)xadj;
979       mat_graph->adjncy  = (PetscInt*)adjncy;
980       mat_graph->freecsr = PETSC_TRUE;
981     } else if (copymode == PETSC_USE_POINTER) {
982       mat_graph->xadj    = (PetscInt*)xadj;
983       mat_graph->adjncy  = (PetscInt*)adjncy;
984       mat_graph->freecsr = PETSC_FALSE;
985     } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Unsupported copy mode %D",copymode);
986     mat_graph->nvtxs_csr = nvtxs;
987     pcbddc->recompute_topography = PETSC_TRUE;
988   }
989   PetscFunctionReturn(0);
990 }
991 
992 /*@
993  PCBDDCSetLocalAdjacencyGraph - Set adjacency structure (CSR graph) of the local degrees of freedom.
994 
995    Not collective
996 
997    Input Parameters:
998 +  pc - the preconditioning context.
999 .  nvtxs - number of local vertices of the graph (i.e., the number of local dofs).
1000 .  xadj, adjncy - the connectivity of the dofs in CSR format.
1001 -  copymode - supported modes are PETSC_COPY_VALUES, PETSC_USE_POINTER or PETSC_OWN_POINTER.
1002 
1003    Level: intermediate
1004 
1005    Notes: A dof is considered connected with all local dofs if xadj[dof+1]-xadj[dof] == 1 and adjncy[xadj[dof]] is negative.
1006 
1007 .seealso: PCBDDC,PetscCopyMode
1008 @*/
1009 PetscErrorCode PCBDDCSetLocalAdjacencyGraph(PC pc,PetscInt nvtxs,const PetscInt xadj[],const PetscInt adjncy[], PetscCopyMode copymode)
1010 {
1011   void (*f)(void) = 0;
1012   PetscErrorCode ierr;
1013 
1014   PetscFunctionBegin;
1015   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
1016   if (nvtxs) {
1017     PetscValidIntPointer(xadj,3);
1018     if (xadj[nvtxs]) PetscValidIntPointer(adjncy,4);
1019   }
1020   ierr = PetscTryMethod(pc,"PCBDDCSetLocalAdjacencyGraph_C",(PC,PetscInt,const PetscInt[],const PetscInt[],PetscCopyMode),(pc,nvtxs,xadj,adjncy,copymode));CHKERRQ(ierr);
1021   /* free arrays if PCBDDC is not the PC type */
1022   ierr = PetscObjectQueryFunction((PetscObject)pc,"PCBDDCSetLocalAdjacencyGraph_C",&f);CHKERRQ(ierr);
1023   if (!f && copymode == PETSC_OWN_POINTER) {
1024     ierr = PetscFree(xadj);CHKERRQ(ierr);
1025     ierr = PetscFree(adjncy);CHKERRQ(ierr);
1026   }
1027   PetscFunctionReturn(0);
1028 }
1029 
1030 static PetscErrorCode PCBDDCSetDofsSplittingLocal_BDDC(PC pc,PetscInt n_is, IS ISForDofs[])
1031 {
1032   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
1033   PetscInt       i;
1034   PetscBool      isequal = PETSC_FALSE;
1035   PetscErrorCode ierr;
1036 
1037   PetscFunctionBegin;
1038   if (pcbddc->n_ISForDofsLocal == n_is) {
1039     for (i=0;i<n_is;i++) {
1040       PetscBool isequalt;
1041       ierr = ISEqual(ISForDofs[i],pcbddc->ISForDofsLocal[i],&isequalt);CHKERRQ(ierr);
1042       if (!isequalt) break;
1043     }
1044     if (i == n_is) isequal = PETSC_TRUE;
1045   }
1046   for (i=0;i<n_is;i++) {
1047     ierr = PetscObjectReference((PetscObject)ISForDofs[i]);CHKERRQ(ierr);
1048   }
1049   /* Destroy ISes if they were already set */
1050   for (i=0;i<pcbddc->n_ISForDofsLocal;i++) {
1051     ierr = ISDestroy(&pcbddc->ISForDofsLocal[i]);CHKERRQ(ierr);
1052   }
1053   ierr = PetscFree(pcbddc->ISForDofsLocal);CHKERRQ(ierr);
1054   /* last user setting takes precendence -> destroy any other customization */
1055   for (i=0;i<pcbddc->n_ISForDofs;i++) {
1056     ierr = ISDestroy(&pcbddc->ISForDofs[i]);CHKERRQ(ierr);
1057   }
1058   ierr = PetscFree(pcbddc->ISForDofs);CHKERRQ(ierr);
1059   pcbddc->n_ISForDofs = 0;
1060   /* allocate space then set */
1061   if (n_is) {
1062     ierr = PetscMalloc1(n_is,&pcbddc->ISForDofsLocal);CHKERRQ(ierr);
1063   }
1064   for (i=0;i<n_is;i++) {
1065     pcbddc->ISForDofsLocal[i] = ISForDofs[i];
1066   }
1067   pcbddc->n_ISForDofsLocal = n_is;
1068   if (n_is) pcbddc->user_provided_isfordofs = PETSC_TRUE;
1069   if (!isequal) pcbddc->recompute_topography = PETSC_TRUE;
1070   PetscFunctionReturn(0);
1071 }
1072 
1073 /*@
1074  PCBDDCSetDofsSplittingLocal - Set index sets defining fields of the local subdomain matrix
1075 
1076    Collective
1077 
1078    Input Parameters:
1079 +  pc - the preconditioning context
1080 .  n_is - number of index sets defining the fields
1081 -  ISForDofs - array of IS describing the fields in local ordering
1082 
1083    Level: intermediate
1084 
1085    Notes:
1086      n_is should be the same among processes. Not all nodes need to be listed: unlisted nodes will belong to the complement field.
1087 
1088 .seealso: PCBDDC
1089 @*/
1090 PetscErrorCode PCBDDCSetDofsSplittingLocal(PC pc,PetscInt n_is, IS ISForDofs[])
1091 {
1092   PetscInt       i;
1093   PetscErrorCode ierr;
1094 
1095   PetscFunctionBegin;
1096   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
1097   PetscValidLogicalCollectiveInt(pc,n_is,2);
1098   for (i=0;i<n_is;i++) {
1099     PetscCheckSameComm(pc,1,ISForDofs[i],3);
1100     PetscValidHeaderSpecific(ISForDofs[i],IS_CLASSID,3);
1101   }
1102   ierr = PetscTryMethod(pc,"PCBDDCSetDofsSplittingLocal_C",(PC,PetscInt,IS[]),(pc,n_is,ISForDofs));CHKERRQ(ierr);
1103   PetscFunctionReturn(0);
1104 }
1105 
1106 static PetscErrorCode PCBDDCSetDofsSplitting_BDDC(PC pc,PetscInt n_is, IS ISForDofs[])
1107 {
1108   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
1109   PetscInt       i;
1110   PetscBool      isequal = PETSC_FALSE;
1111   PetscErrorCode ierr;
1112 
1113   PetscFunctionBegin;
1114   if (pcbddc->n_ISForDofs == n_is) {
1115     for (i=0;i<n_is;i++) {
1116       PetscBool isequalt;
1117       ierr = ISEqual(ISForDofs[i],pcbddc->ISForDofs[i],&isequalt);CHKERRQ(ierr);
1118       if (!isequalt) break;
1119     }
1120     if (i == n_is) isequal = PETSC_TRUE;
1121   }
1122   for (i=0;i<n_is;i++) {
1123     ierr = PetscObjectReference((PetscObject)ISForDofs[i]);CHKERRQ(ierr);
1124   }
1125   /* Destroy ISes if they were already set */
1126   for (i=0;i<pcbddc->n_ISForDofs;i++) {
1127     ierr = ISDestroy(&pcbddc->ISForDofs[i]);CHKERRQ(ierr);
1128   }
1129   ierr = PetscFree(pcbddc->ISForDofs);CHKERRQ(ierr);
1130   /* last user setting takes precendence -> destroy any other customization */
1131   for (i=0;i<pcbddc->n_ISForDofsLocal;i++) {
1132     ierr = ISDestroy(&pcbddc->ISForDofsLocal[i]);CHKERRQ(ierr);
1133   }
1134   ierr = PetscFree(pcbddc->ISForDofsLocal);CHKERRQ(ierr);
1135   pcbddc->n_ISForDofsLocal = 0;
1136   /* allocate space then set */
1137   if (n_is) {
1138     ierr = PetscMalloc1(n_is,&pcbddc->ISForDofs);CHKERRQ(ierr);
1139   }
1140   for (i=0;i<n_is;i++) {
1141     pcbddc->ISForDofs[i] = ISForDofs[i];
1142   }
1143   pcbddc->n_ISForDofs = n_is;
1144   if (n_is) pcbddc->user_provided_isfordofs = PETSC_TRUE;
1145   if (!isequal) pcbddc->recompute_topography = PETSC_TRUE;
1146   PetscFunctionReturn(0);
1147 }
1148 
1149 /*@
1150  PCBDDCSetDofsSplitting - Set index sets defining fields of the global matrix
1151 
1152    Collective
1153 
1154    Input Parameters:
1155 +  pc - the preconditioning context
1156 .  n_is - number of index sets defining the fields
1157 -  ISForDofs - array of IS describing the fields in global ordering
1158 
1159    Level: intermediate
1160 
1161    Notes:
1162      Any process can list any global node. Not all nodes need to be listed: unlisted nodes will belong to the complement field.
1163 
1164 .seealso: PCBDDC
1165 @*/
1166 PetscErrorCode PCBDDCSetDofsSplitting(PC pc,PetscInt n_is, IS ISForDofs[])
1167 {
1168   PetscInt       i;
1169   PetscErrorCode ierr;
1170 
1171   PetscFunctionBegin;
1172   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
1173   PetscValidLogicalCollectiveInt(pc,n_is,2);
1174   for (i=0;i<n_is;i++) {
1175     PetscValidHeaderSpecific(ISForDofs[i],IS_CLASSID,3);
1176     PetscCheckSameComm(pc,1,ISForDofs[i],3);
1177   }
1178   ierr = PetscTryMethod(pc,"PCBDDCSetDofsSplitting_C",(PC,PetscInt,IS[]),(pc,n_is,ISForDofs));CHKERRQ(ierr);
1179   PetscFunctionReturn(0);
1180 }
1181 
1182 /*
1183    PCPreSolve_BDDC - Changes the right hand side and (if necessary) the initial
1184                      guess if a transformation of basis approach has been selected.
1185 
1186    Input Parameter:
1187 +  pc - the preconditioner contex
1188 
1189    Application Interface Routine: PCPreSolve()
1190 
1191    Notes:
1192      The interface routine PCPreSolve() is not usually called directly by
1193    the user, but instead is called by KSPSolve().
1194 */
1195 static PetscErrorCode PCPreSolve_BDDC(PC pc, KSP ksp, Vec rhs, Vec x)
1196 {
1197   PetscErrorCode ierr;
1198   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
1199   PC_IS          *pcis = (PC_IS*)(pc->data);
1200   Vec            used_vec;
1201   PetscBool      save_rhs = PETSC_TRUE, benign_correction_computed;
1202 
1203   PetscFunctionBegin;
1204   /* if we are working with CG, one dirichlet solve can be avoided during Krylov iterations */
1205   if (ksp) {
1206     PetscBool iscg, isgroppcg, ispipecg, ispipecgrr;
1207     ierr = PetscObjectTypeCompare((PetscObject)ksp,KSPCG,&iscg);CHKERRQ(ierr);
1208     ierr = PetscObjectTypeCompare((PetscObject)ksp,KSPGROPPCG,&isgroppcg);CHKERRQ(ierr);
1209     ierr = PetscObjectTypeCompare((PetscObject)ksp,KSPPIPECG,&ispipecg);CHKERRQ(ierr);
1210     ierr = PetscObjectTypeCompare((PetscObject)ksp,KSPPIPECGRR,&ispipecgrr);CHKERRQ(ierr);
1211     if (pcbddc->benign_apply_coarse_only || pcbddc->switch_static || (!iscg && !isgroppcg && !ispipecg && !ispipecgrr)) {
1212       ierr = PCBDDCSetUseExactDirichlet(pc,PETSC_FALSE);CHKERRQ(ierr);
1213     }
1214   }
1215   if (pcbddc->benign_apply_coarse_only || pcbddc->switch_static) {
1216     ierr = PCBDDCSetUseExactDirichlet(pc,PETSC_FALSE);CHKERRQ(ierr);
1217   }
1218 
1219   /* Creates parallel work vectors used in presolve */
1220   if (!pcbddc->original_rhs) {
1221     ierr = VecDuplicate(pcis->vec1_global,&pcbddc->original_rhs);CHKERRQ(ierr);
1222   }
1223   if (!pcbddc->temp_solution) {
1224     ierr = VecDuplicate(pcis->vec1_global,&pcbddc->temp_solution);CHKERRQ(ierr);
1225   }
1226 
1227   pcbddc->temp_solution_used = PETSC_FALSE;
1228   if (x) {
1229     ierr = PetscObjectReference((PetscObject)x);CHKERRQ(ierr);
1230     used_vec = x;
1231   } else { /* it can only happen when calling PCBDDCMatFETIDPGetRHS */
1232     ierr = PetscObjectReference((PetscObject)pcbddc->temp_solution);CHKERRQ(ierr);
1233     used_vec = pcbddc->temp_solution;
1234     ierr = VecSet(used_vec,0.0);CHKERRQ(ierr);
1235     pcbddc->temp_solution_used = PETSC_TRUE;
1236     ierr = VecCopy(rhs,pcbddc->original_rhs);CHKERRQ(ierr);
1237     save_rhs = PETSC_FALSE;
1238     pcbddc->eliminate_dirdofs = PETSC_TRUE;
1239   }
1240 
1241   /* hack into ksp data structure since PCPreSolve comes earlier than setting to zero the guess in src/ksp/ksp/interface/itfunc.c */
1242   if (ksp) {
1243     /* store the flag for the initial guess since it will be restored back during PCPostSolve_BDDC */
1244     ierr = KSPGetInitialGuessNonzero(ksp,&pcbddc->ksp_guess_nonzero);CHKERRQ(ierr);
1245     if (!pcbddc->ksp_guess_nonzero) {
1246       ierr = VecSet(used_vec,0.0);CHKERRQ(ierr);
1247     }
1248   }
1249 
1250   pcbddc->rhs_change = PETSC_FALSE;
1251   /* Take into account zeroed rows -> change rhs and store solution removed */
1252   if (rhs && pcbddc->eliminate_dirdofs) {
1253     IS dirIS = NULL;
1254 
1255     /* DirichletBoundariesLocal may not be consistent among neighbours; gets a dirichlet dofs IS from graph (may be cached) */
1256     ierr = PCBDDCGraphGetDirichletDofs(pcbddc->mat_graph,&dirIS);CHKERRQ(ierr);
1257     if (dirIS) {
1258       Mat_IS            *matis = (Mat_IS*)pc->pmat->data;
1259       PetscInt          dirsize,i,*is_indices;
1260       PetscScalar       *array_x;
1261       const PetscScalar *array_diagonal;
1262 
1263       ierr = MatGetDiagonal(pc->pmat,pcis->vec1_global);CHKERRQ(ierr);
1264       ierr = VecPointwiseDivide(pcis->vec1_global,rhs,pcis->vec1_global);CHKERRQ(ierr);
1265       ierr = VecScatterBegin(matis->rctx,pcis->vec1_global,pcis->vec2_N,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1266       ierr = VecScatterEnd(matis->rctx,pcis->vec1_global,pcis->vec2_N,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1267       ierr = VecScatterBegin(matis->rctx,used_vec,pcis->vec1_N,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1268       ierr = VecScatterEnd(matis->rctx,used_vec,pcis->vec1_N,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1269       ierr = ISGetLocalSize(dirIS,&dirsize);CHKERRQ(ierr);
1270       ierr = VecGetArray(pcis->vec1_N,&array_x);CHKERRQ(ierr);
1271       ierr = VecGetArrayRead(pcis->vec2_N,&array_diagonal);CHKERRQ(ierr);
1272       ierr = ISGetIndices(dirIS,(const PetscInt**)&is_indices);CHKERRQ(ierr);
1273       for (i=0; i<dirsize; i++) array_x[is_indices[i]] = array_diagonal[is_indices[i]];
1274       ierr = ISRestoreIndices(dirIS,(const PetscInt**)&is_indices);CHKERRQ(ierr);
1275       ierr = VecRestoreArrayRead(pcis->vec2_N,&array_diagonal);CHKERRQ(ierr);
1276       ierr = VecRestoreArray(pcis->vec1_N,&array_x);CHKERRQ(ierr);
1277       ierr = VecScatterBegin(matis->rctx,pcis->vec1_N,used_vec,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1278       ierr = VecScatterEnd(matis->rctx,pcis->vec1_N,used_vec,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1279       pcbddc->rhs_change = PETSC_TRUE;
1280       ierr = ISDestroy(&dirIS);CHKERRQ(ierr);
1281     }
1282   }
1283 
1284   /* remove the computed solution or the initial guess from the rhs */
1285   if (pcbddc->rhs_change || (ksp && pcbddc->ksp_guess_nonzero) ) {
1286     /* save the original rhs */
1287     if (save_rhs) {
1288       ierr = VecSwap(rhs,pcbddc->original_rhs);CHKERRQ(ierr);
1289       save_rhs = PETSC_FALSE;
1290     }
1291     pcbddc->rhs_change = PETSC_TRUE;
1292     ierr = VecScale(used_vec,-1.0);CHKERRQ(ierr);
1293     ierr = MatMultAdd(pc->mat,used_vec,pcbddc->original_rhs,rhs);CHKERRQ(ierr);
1294     ierr = VecScale(used_vec,-1.0);CHKERRQ(ierr);
1295     ierr = VecCopy(used_vec,pcbddc->temp_solution);CHKERRQ(ierr);
1296     pcbddc->temp_solution_used = PETSC_TRUE;
1297     if (ksp) {
1298       ierr = KSPSetInitialGuessNonzero(ksp,PETSC_FALSE);CHKERRQ(ierr);
1299     }
1300   }
1301   ierr = VecDestroy(&used_vec);CHKERRQ(ierr);
1302 
1303   /* compute initial vector in benign space if needed
1304      and remove non-benign solution from the rhs */
1305   benign_correction_computed = PETSC_FALSE;
1306   if (rhs && pcbddc->benign_compute_correction && pcbddc->benign_have_null) {
1307     /* compute u^*_h using ideas similar to those in Xuemin Tu's PhD thesis (see Section 4.8.1)
1308        Recursively apply BDDC in the multilevel case */
1309     if (!pcbddc->benign_vec) {
1310       ierr = VecDuplicate(rhs,&pcbddc->benign_vec);CHKERRQ(ierr);
1311     }
1312     pcbddc->benign_apply_coarse_only = PETSC_TRUE;
1313     if (!pcbddc->benign_skip_correction) {
1314       ierr = PCApply_BDDC(pc,rhs,pcbddc->benign_vec);CHKERRQ(ierr);
1315       benign_correction_computed = PETSC_TRUE;
1316       if (pcbddc->temp_solution_used) {
1317         ierr = VecAXPY(pcbddc->temp_solution,1.0,pcbddc->benign_vec);CHKERRQ(ierr);
1318       }
1319       ierr = VecScale(pcbddc->benign_vec,-1.0);CHKERRQ(ierr);
1320       /* store the original rhs if not done earlier */
1321       if (save_rhs) {
1322         ierr = VecSwap(rhs,pcbddc->original_rhs);CHKERRQ(ierr);
1323       }
1324       if (pcbddc->rhs_change) {
1325         ierr = MatMultAdd(pc->mat,pcbddc->benign_vec,rhs,rhs);CHKERRQ(ierr);
1326       } else {
1327         ierr = MatMultAdd(pc->mat,pcbddc->benign_vec,pcbddc->original_rhs,rhs);CHKERRQ(ierr);
1328       }
1329       pcbddc->rhs_change = PETSC_TRUE;
1330     }
1331     pcbddc->benign_apply_coarse_only = PETSC_FALSE;
1332   }
1333 
1334   /* dbg output */
1335   if (pcbddc->dbg_flag && benign_correction_computed) {
1336     Vec v;
1337     ierr = VecDuplicate(pcis->vec1_global,&v);CHKERRQ(ierr);
1338     ierr = MatMultTranspose(pcbddc->ChangeOfBasisMatrix,rhs,v);CHKERRQ(ierr);
1339     ierr = PCBDDCBenignGetOrSetP0(pc,v,PETSC_TRUE);CHKERRQ(ierr);
1340     ierr = PetscViewerASCIIPrintf(pcbddc->dbg_viewer,"LEVEL %D: is the correction benign?\n",pcbddc->current_level);CHKERRQ(ierr);
1341     ierr = PetscScalarView(pcbddc->benign_n,pcbddc->benign_p0,PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)pc)));CHKERRQ(ierr);
1342     ierr = VecDestroy(&v);CHKERRQ(ierr);
1343   }
1344 
1345   /* set initial guess if using PCG */
1346   pcbddc->exact_dirichlet_trick_app = PETSC_FALSE;
1347   if (x && pcbddc->use_exact_dirichlet_trick) {
1348     ierr = VecSet(x,0.0);CHKERRQ(ierr);
1349     if (pcbddc->ChangeOfBasisMatrix && pcbddc->change_interior) {
1350       if (benign_correction_computed) { /* we have already saved the changed rhs */
1351         ierr = VecLockPop(pcis->vec1_global);CHKERRQ(ierr);
1352       } else {
1353         ierr = MatMultTranspose(pcbddc->ChangeOfBasisMatrix,rhs,pcis->vec1_global);CHKERRQ(ierr);
1354       }
1355       ierr = VecScatterBegin(pcis->global_to_D,pcis->vec1_global,pcis->vec1_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1356       ierr = VecScatterEnd(pcis->global_to_D,pcis->vec1_global,pcis->vec1_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1357     } else {
1358       ierr = VecScatterBegin(pcis->global_to_D,rhs,pcis->vec1_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1359       ierr = VecScatterEnd(pcis->global_to_D,rhs,pcis->vec1_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1360     }
1361     ierr = KSPSolve(pcbddc->ksp_D,pcis->vec1_D,pcis->vec2_D);CHKERRQ(ierr);
1362     if (pcbddc->ChangeOfBasisMatrix && pcbddc->change_interior) {
1363       ierr = VecSet(pcis->vec1_global,0.);CHKERRQ(ierr);
1364       ierr = VecScatterBegin(pcis->global_to_D,pcis->vec2_D,pcis->vec1_global,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1365       ierr = VecScatterEnd(pcis->global_to_D,pcis->vec2_D,pcis->vec1_global,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1366       ierr = MatMult(pcbddc->ChangeOfBasisMatrix,pcis->vec1_global,x);CHKERRQ(ierr);
1367     } else {
1368       ierr = VecScatterBegin(pcis->global_to_D,pcis->vec2_D,x,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1369       ierr = VecScatterEnd(pcis->global_to_D,pcis->vec2_D,x,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1370     }
1371     if (ksp) {
1372       ierr = KSPSetInitialGuessNonzero(ksp,PETSC_TRUE);CHKERRQ(ierr);
1373     }
1374     pcbddc->exact_dirichlet_trick_app = PETSC_TRUE;
1375   } else if (pcbddc->ChangeOfBasisMatrix && pcbddc->change_interior && benign_correction_computed && pcbddc->use_exact_dirichlet_trick) {
1376     ierr = VecLockPop(pcis->vec1_global);CHKERRQ(ierr);
1377   }
1378   PetscFunctionReturn(0);
1379 }
1380 
1381 /*
1382    PCPostSolve_BDDC - Changes the computed solution if a transformation of basis
1383                      approach has been selected. Also, restores rhs to its original state.
1384 
1385    Input Parameter:
1386 +  pc - the preconditioner contex
1387 
1388    Application Interface Routine: PCPostSolve()
1389 
1390    Notes:
1391      The interface routine PCPostSolve() is not usually called directly by
1392      the user, but instead is called by KSPSolve().
1393 */
1394 static PetscErrorCode PCPostSolve_BDDC(PC pc, KSP ksp, Vec rhs, Vec x)
1395 {
1396   PetscErrorCode ierr;
1397   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
1398 
1399   PetscFunctionBegin;
1400   /* add solution removed in presolve */
1401   if (x && pcbddc->rhs_change) {
1402     if (pcbddc->temp_solution_used) {
1403       ierr = VecAXPY(x,1.0,pcbddc->temp_solution);CHKERRQ(ierr);
1404     } else if (pcbddc->benign_compute_correction && pcbddc->benign_vec) {
1405       ierr = VecAXPY(x,-1.0,pcbddc->benign_vec);CHKERRQ(ierr);
1406     }
1407     /* restore to original state (not for FETI-DP) */
1408     if (ksp) pcbddc->temp_solution_used = PETSC_FALSE;
1409   }
1410 
1411   /* restore rhs to its original state (not needed for FETI-DP) */
1412   if (rhs && pcbddc->rhs_change) {
1413     ierr = VecSwap(rhs,pcbddc->original_rhs);CHKERRQ(ierr);
1414     pcbddc->rhs_change = PETSC_FALSE;
1415   }
1416   /* restore ksp guess state */
1417   if (ksp) {
1418     ierr = KSPSetInitialGuessNonzero(ksp,pcbddc->ksp_guess_nonzero);CHKERRQ(ierr);
1419     /* reset flag for exact dirichlet trick */
1420     pcbddc->exact_dirichlet_trick_app = PETSC_FALSE;
1421   }
1422   PetscFunctionReturn(0);
1423 }
1424 
1425 /*
1426    PCSetUp_BDDC - Prepares for the use of the BDDC preconditioner
1427                   by setting data structures and options.
1428 
1429    Input Parameter:
1430 +  pc - the preconditioner context
1431 
1432    Application Interface Routine: PCSetUp()
1433 
1434    Notes:
1435      The interface routine PCSetUp() is not usually called directly by
1436      the user, but instead is called by PCApply() if necessary.
1437 */
1438 PetscErrorCode PCSetUp_BDDC(PC pc)
1439 {
1440   PC_BDDC*        pcbddc = (PC_BDDC*)pc->data;
1441   PCBDDCSubSchurs sub_schurs;
1442   Mat_IS*         matis;
1443   MatNullSpace    nearnullspace;
1444   Mat             lA;
1445   IS              lP,zerodiag = NULL;
1446   PetscInt        nrows,ncols;
1447   PetscBool       computesubschurs;
1448   PetscBool       computeconstraintsmatrix;
1449   PetscBool       new_nearnullspace_provided,ismatis;
1450   PetscErrorCode  ierr;
1451 
1452   PetscFunctionBegin;
1453   ierr = PetscObjectTypeCompare((PetscObject)pc->pmat,MATIS,&ismatis);CHKERRQ(ierr);
1454   if (!ismatis) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_ARG_WRONG,"PCBDDC preconditioner requires matrix of type MATIS");
1455   ierr = MatGetSize(pc->pmat,&nrows,&ncols);CHKERRQ(ierr);
1456   if (nrows != ncols) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"PCBDDC preconditioner requires a square preconditioning matrix");
1457   matis = (Mat_IS*)pc->pmat->data;
1458   /* the following lines of code should be replaced by a better logic between PCIS, PCNN, PCBDDC and other future nonoverlapping preconditioners */
1459   /* For BDDC we need to define a local "Neumann" problem different to that defined in PCISSetup
1460      Also, BDDC builds its own KSP for the Dirichlet problem */
1461   if (!pc->setupcalled || pc->flag == DIFFERENT_NONZERO_PATTERN) pcbddc->recompute_topography = PETSC_TRUE;
1462   if (pcbddc->recompute_topography) {
1463     pcbddc->graphanalyzed    = PETSC_FALSE;
1464     computeconstraintsmatrix = PETSC_TRUE;
1465   } else {
1466     computeconstraintsmatrix = PETSC_FALSE;
1467   }
1468 
1469   /* check parameters' compatibility */
1470   if (!pcbddc->use_deluxe_scaling) pcbddc->deluxe_zerorows = PETSC_FALSE;
1471   pcbddc->adaptive_selection = (PetscBool)(pcbddc->adaptive_threshold > 0.0);
1472   pcbddc->adaptive_userdefined = (PetscBool)(pcbddc->adaptive_selection && pcbddc->adaptive_userdefined);
1473   if (pcbddc->adaptive_selection) pcbddc->use_faces = PETSC_TRUE;
1474 
1475   computesubschurs = (PetscBool)(pcbddc->adaptive_selection || pcbddc->use_deluxe_scaling);
1476   if (pcbddc->switch_static) {
1477     PetscBool ismatis;
1478     ierr = PetscObjectTypeCompare((PetscObject)pc->mat,MATIS,&ismatis);CHKERRQ(ierr);
1479     if (!ismatis) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"When the static switch is one, the iteration matrix should be of type MATIS");
1480   }
1481 
1482   /* activate all connected components if the netflux has been requested */
1483   if (pcbddc->compute_nonetflux) {
1484     pcbddc->use_vertices = PETSC_TRUE;
1485     pcbddc->use_edges = PETSC_TRUE;
1486     pcbddc->use_faces = PETSC_TRUE;
1487   }
1488 
1489   /* Get stdout for dbg */
1490   if (pcbddc->dbg_flag) {
1491     if (!pcbddc->dbg_viewer) {
1492       pcbddc->dbg_viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)pc));
1493       ierr = PetscViewerASCIIPushSynchronized(pcbddc->dbg_viewer);CHKERRQ(ierr);
1494     }
1495     ierr = PetscViewerASCIIAddTab(pcbddc->dbg_viewer,2*pcbddc->current_level);CHKERRQ(ierr);
1496   }
1497 
1498   /* process topology information */
1499   if (pcbddc->recompute_topography) {
1500     ierr = PCBDDCComputeLocalTopologyInfo(pc);CHKERRQ(ierr);
1501     if (pcbddc->discretegradient) {
1502       ierr = PCBDDCNedelecSupport(pc);CHKERRQ(ierr);
1503     }
1504   }
1505 
1506   /* change basis if requested by the user */
1507   if (pcbddc->user_ChangeOfBasisMatrix) {
1508     /* use_change_of_basis flag is used to automatically compute a change of basis from constraints */
1509     pcbddc->use_change_of_basis = PETSC_FALSE;
1510     ierr = PCBDDCComputeLocalMatrix(pc,pcbddc->user_ChangeOfBasisMatrix);CHKERRQ(ierr);
1511   } else {
1512     ierr = MatDestroy(&pcbddc->local_mat);CHKERRQ(ierr);
1513     ierr = PetscObjectReference((PetscObject)matis->A);CHKERRQ(ierr);
1514     pcbddc->local_mat = matis->A;
1515   }
1516 
1517   /*
1518      Compute change of basis on local pressures (aka zerodiag dofs) with the benign trick
1519      This should come earlier then PCISSetUp for extracting the correct subdomain matrices
1520   */
1521   ierr = PCBDDCBenignShellMat(pc,PETSC_TRUE);CHKERRQ(ierr);
1522   if (pcbddc->benign_saddle_point) {
1523     PC_IS* pcis = (PC_IS*)pc->data;
1524 
1525     if (pcbddc->user_ChangeOfBasisMatrix || pcbddc->use_change_of_basis || !computesubschurs) pcbddc->benign_change_explicit = PETSC_TRUE;
1526     /* detect local saddle point and change the basis in pcbddc->local_mat (TODO: reuse case) */
1527     ierr = PCBDDCBenignDetectSaddlePoint(pc,&zerodiag);CHKERRQ(ierr);
1528     /* pop B0 mat from local mat */
1529     ierr = PCBDDCBenignPopOrPushB0(pc,PETSC_TRUE);CHKERRQ(ierr);
1530     /* give pcis a hint to not reuse submatrices during PCISCreate */
1531     if (pc->flag == SAME_NONZERO_PATTERN && pcis->reusesubmatrices == PETSC_TRUE) {
1532       if (pcbddc->benign_n && (pcbddc->benign_change_explicit || pcbddc->dbg_flag)) {
1533         pcis->reusesubmatrices = PETSC_FALSE;
1534       } else {
1535         pcis->reusesubmatrices = PETSC_TRUE;
1536       }
1537     } else {
1538       pcis->reusesubmatrices = PETSC_FALSE;
1539     }
1540   }
1541 
1542   /* propagate relevant information -> TODO remove*/
1543 #if !defined(PETSC_USE_COMPLEX) /* workaround for reals */
1544   if (matis->A->symmetric_set) {
1545     ierr = MatSetOption(pcbddc->local_mat,MAT_HERMITIAN,matis->A->symmetric);CHKERRQ(ierr);
1546   }
1547 #endif
1548   if (matis->A->symmetric_set) {
1549     ierr = MatSetOption(pcbddc->local_mat,MAT_SYMMETRIC,matis->A->symmetric);CHKERRQ(ierr);
1550   }
1551   if (matis->A->spd_set) {
1552     ierr = MatSetOption(pcbddc->local_mat,MAT_SPD,matis->A->spd);CHKERRQ(ierr);
1553   }
1554 
1555   /* Set up all the "iterative substructuring" common block without computing solvers */
1556   {
1557     Mat temp_mat;
1558 
1559     temp_mat = matis->A;
1560     matis->A = pcbddc->local_mat;
1561     ierr = PCISSetUp(pc,PETSC_FALSE);CHKERRQ(ierr);
1562     pcbddc->local_mat = matis->A;
1563     matis->A = temp_mat;
1564   }
1565 
1566   /* Analyze interface */
1567   if (!pcbddc->graphanalyzed) {
1568     ierr = PCBDDCAnalyzeInterface(pc);CHKERRQ(ierr);
1569     computeconstraintsmatrix = PETSC_TRUE;
1570     if (pcbddc->adaptive_selection && !pcbddc->use_deluxe_scaling && !pcbddc->mat_graph->twodim) {
1571       SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Cannot compute the adaptive primal space for a problem with 3D edges without deluxe scaling");
1572     }
1573     if (pcbddc->compute_nonetflux) {
1574       MatNullSpace nnfnnsp;
1575 
1576       if (!pcbddc->divudotp) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"Missing divudotp operator");
1577       ierr = PCBDDCComputeNoNetFlux(pc->pmat,pcbddc->divudotp,pcbddc->divudotp_trans,pcbddc->divudotp_vl2l,pcbddc->mat_graph,&nnfnnsp);CHKERRQ(ierr);
1578       /* TODO what if a nearnullspace is already attached? */
1579       ierr = MatSetNearNullSpace(pc->pmat,nnfnnsp);CHKERRQ(ierr);
1580       ierr = MatNullSpaceDestroy(&nnfnnsp);CHKERRQ(ierr);
1581     }
1582   }
1583 
1584   /* check existence of a divergence free extension, i.e.
1585      b(v_I,p_0) = 0 for all v_I (raise error if not).
1586      Also, check that PCBDDCBenignGetOrSetP0 works */
1587   if (pcbddc->benign_saddle_point && pcbddc->dbg_flag > 1) {
1588     ierr = PCBDDCBenignCheck(pc,zerodiag);CHKERRQ(ierr);
1589   }
1590   ierr = ISDestroy(&zerodiag);CHKERRQ(ierr);
1591 
1592   /* Setup local dirichlet solver ksp_D and sub_schurs solvers */
1593   if (computesubschurs && pcbddc->recompute_topography) {
1594     ierr = PCBDDCInitSubSchurs(pc);CHKERRQ(ierr);
1595   }
1596   /* SetUp Scaling operator (scaling matrices could be needed in SubSchursSetUp)*/
1597   if (!pcbddc->use_deluxe_scaling) {
1598     ierr = PCBDDCScalingSetUp(pc);CHKERRQ(ierr);
1599   }
1600 
1601   /* finish setup solvers and do adaptive selection of constraints */
1602   sub_schurs = pcbddc->sub_schurs;
1603   if (sub_schurs && sub_schurs->schur_explicit) {
1604     if (computesubschurs) {
1605       ierr = PCBDDCSetUpSubSchurs(pc);CHKERRQ(ierr);
1606     }
1607     ierr = PCBDDCSetUpLocalSolvers(pc,PETSC_TRUE,PETSC_FALSE);CHKERRQ(ierr);
1608   } else {
1609     ierr = PCBDDCSetUpLocalSolvers(pc,PETSC_TRUE,PETSC_FALSE);CHKERRQ(ierr);
1610     if (computesubschurs) {
1611       ierr = PCBDDCSetUpSubSchurs(pc);CHKERRQ(ierr);
1612     }
1613   }
1614   if (pcbddc->adaptive_selection) {
1615     ierr = PCBDDCAdaptiveSelection(pc);CHKERRQ(ierr);
1616     computeconstraintsmatrix = PETSC_TRUE;
1617   }
1618 
1619   /* infer if NullSpace object attached to Mat via MatSetNearNullSpace has changed */
1620   new_nearnullspace_provided = PETSC_FALSE;
1621   ierr = MatGetNearNullSpace(pc->pmat,&nearnullspace);CHKERRQ(ierr);
1622   if (pcbddc->onearnullspace) { /* already used nearnullspace */
1623     if (!nearnullspace) { /* near null space attached to mat has been destroyed */
1624       new_nearnullspace_provided = PETSC_TRUE;
1625     } else {
1626       /* determine if the two nullspaces are different (should be lightweight) */
1627       if (nearnullspace != pcbddc->onearnullspace) {
1628         new_nearnullspace_provided = PETSC_TRUE;
1629       } else { /* maybe the user has changed the content of the nearnullspace so check vectors ObjectStateId */
1630         PetscInt         i;
1631         const Vec        *nearnullvecs;
1632         PetscObjectState state;
1633         PetscInt         nnsp_size;
1634         ierr = MatNullSpaceGetVecs(nearnullspace,NULL,&nnsp_size,&nearnullvecs);CHKERRQ(ierr);
1635         for (i=0;i<nnsp_size;i++) {
1636           ierr = PetscObjectStateGet((PetscObject)nearnullvecs[i],&state);CHKERRQ(ierr);
1637           if (pcbddc->onearnullvecs_state[i] != state) {
1638             new_nearnullspace_provided = PETSC_TRUE;
1639             break;
1640           }
1641         }
1642       }
1643     }
1644   } else {
1645     if (!nearnullspace) { /* both nearnullspaces are null */
1646       new_nearnullspace_provided = PETSC_FALSE;
1647     } else { /* nearnullspace attached later */
1648       new_nearnullspace_provided = PETSC_TRUE;
1649     }
1650   }
1651 
1652   /* Setup constraints and related work vectors */
1653   /* reset primal space flags */
1654   pcbddc->new_primal_space = PETSC_FALSE;
1655   pcbddc->new_primal_space_local = PETSC_FALSE;
1656   if (computeconstraintsmatrix || new_nearnullspace_provided) {
1657     /* It also sets the primal space flags */
1658     ierr = PCBDDCConstraintsSetUp(pc);CHKERRQ(ierr);
1659   }
1660   /* Allocate needed local vectors (which depends on quantities defined during ConstraintsSetUp) */
1661   ierr = PCBDDCSetUpLocalWorkVectors(pc);CHKERRQ(ierr);
1662 
1663   if (pcbddc->use_change_of_basis) {
1664     PC_IS *pcis = (PC_IS*)(pc->data);
1665 
1666     ierr = PCBDDCComputeLocalMatrix(pc,pcbddc->ChangeOfBasisMatrix);CHKERRQ(ierr);
1667     if (pcbddc->benign_change) {
1668       ierr = MatDestroy(&pcbddc->benign_B0);CHKERRQ(ierr);
1669       /* pop B0 from pcbddc->local_mat */
1670       ierr = PCBDDCBenignPopOrPushB0(pc,PETSC_TRUE);CHKERRQ(ierr);
1671     }
1672     /* get submatrices */
1673     ierr = MatDestroy(&pcis->A_IB);CHKERRQ(ierr);
1674     ierr = MatDestroy(&pcis->A_BI);CHKERRQ(ierr);
1675     ierr = MatDestroy(&pcis->A_BB);CHKERRQ(ierr);
1676     ierr = MatCreateSubMatrix(pcbddc->local_mat,pcis->is_B_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&pcis->A_BB);CHKERRQ(ierr);
1677     ierr = MatCreateSubMatrix(pcbddc->local_mat,pcis->is_I_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&pcis->A_IB);CHKERRQ(ierr);
1678     ierr = MatCreateSubMatrix(pcbddc->local_mat,pcis->is_B_local,pcis->is_I_local,MAT_INITIAL_MATRIX,&pcis->A_BI);CHKERRQ(ierr);
1679     /* set flag in pcis to not reuse submatrices during PCISCreate */
1680     pcis->reusesubmatrices = PETSC_FALSE;
1681   } else if (!pcbddc->user_ChangeOfBasisMatrix && !pcbddc->benign_change) {
1682     ierr = MatDestroy(&pcbddc->local_mat);CHKERRQ(ierr);
1683     ierr = PetscObjectReference((PetscObject)matis->A);CHKERRQ(ierr);
1684     pcbddc->local_mat = matis->A;
1685   }
1686 
1687   /* interface pressure block row for B_C */
1688   ierr = PetscObjectQuery((PetscObject)pc,"__KSPFETIDP_lP" ,(PetscObject*)&lP);CHKERRQ(ierr);
1689   ierr = PetscObjectQuery((PetscObject)pc,"__KSPFETIDP_lA" ,(PetscObject*)&lA);CHKERRQ(ierr);
1690   if (lA && lP) {
1691     PC_IS*    pcis = (PC_IS*)pc->data;
1692     Mat       B_BI,B_BB,Bt_BI,Bt_BB;
1693     PetscBool issym;
1694     ierr = MatIsSymmetric(lA,PETSC_SMALL,&issym);CHKERRQ(ierr);
1695     if (issym) {
1696       ierr = MatCreateSubMatrix(lA,lP,pcis->is_I_local,MAT_INITIAL_MATRIX,&B_BI);CHKERRQ(ierr);
1697       ierr = MatCreateSubMatrix(lA,lP,pcis->is_B_local,MAT_INITIAL_MATRIX,&B_BB);CHKERRQ(ierr);
1698       ierr = MatCreateTranspose(B_BI,&Bt_BI);CHKERRQ(ierr);
1699       ierr = MatCreateTranspose(B_BB,&Bt_BB);CHKERRQ(ierr);
1700     } else {
1701       ierr = MatCreateSubMatrix(lA,lP,pcis->is_I_local,MAT_INITIAL_MATRIX,&B_BI);CHKERRQ(ierr);
1702       ierr = MatCreateSubMatrix(lA,lP,pcis->is_B_local,MAT_INITIAL_MATRIX,&B_BB);CHKERRQ(ierr);
1703       ierr = MatCreateSubMatrix(lA,pcis->is_I_local,lP,MAT_INITIAL_MATRIX,&Bt_BI);CHKERRQ(ierr);
1704       ierr = MatCreateSubMatrix(lA,pcis->is_B_local,lP,MAT_INITIAL_MATRIX,&Bt_BB);CHKERRQ(ierr);
1705     }
1706     ierr = PetscObjectCompose((PetscObject)pc,"__KSPFETIDP_B_BI",(PetscObject)B_BI);CHKERRQ(ierr);
1707     ierr = PetscObjectCompose((PetscObject)pc,"__KSPFETIDP_B_BB",(PetscObject)B_BB);CHKERRQ(ierr);
1708     ierr = PetscObjectCompose((PetscObject)pc,"__KSPFETIDP_Bt_BI",(PetscObject)Bt_BI);CHKERRQ(ierr);
1709     ierr = PetscObjectCompose((PetscObject)pc,"__KSPFETIDP_Bt_BB",(PetscObject)Bt_BB);CHKERRQ(ierr);
1710     ierr = MatDestroy(&B_BI);CHKERRQ(ierr);
1711     ierr = MatDestroy(&B_BB);CHKERRQ(ierr);
1712     ierr = MatDestroy(&Bt_BI);CHKERRQ(ierr);
1713     ierr = MatDestroy(&Bt_BB);CHKERRQ(ierr);
1714   }
1715 
1716   /* SetUp coarse and local Neumann solvers */
1717   ierr = PCBDDCSetUpSolvers(pc);CHKERRQ(ierr);
1718   /* SetUp Scaling operator */
1719   if (pcbddc->use_deluxe_scaling) {
1720     ierr = PCBDDCScalingSetUp(pc);CHKERRQ(ierr);
1721   }
1722 
1723   /* mark topography as done */
1724   pcbddc->recompute_topography = PETSC_FALSE;
1725 
1726   /* wrap pcis->A_IB and pcis->A_BI if we did not change explicitly the variables on the pressures */
1727   ierr = PCBDDCBenignShellMat(pc,PETSC_FALSE);CHKERRQ(ierr);
1728 
1729   if (pcbddc->dbg_flag) {
1730     ierr = PetscViewerASCIISubtractTab(pcbddc->dbg_viewer,2*pcbddc->current_level);CHKERRQ(ierr);
1731   }
1732   PetscFunctionReturn(0);
1733 }
1734 
1735 /*
1736    PCApply_BDDC - Applies the BDDC operator to a vector.
1737 
1738    Input Parameters:
1739 +  pc - the preconditioner context
1740 -  r - input vector (global)
1741 
1742    Output Parameter:
1743 .  z - output vector (global)
1744 
1745    Application Interface Routine: PCApply()
1746  */
1747 PetscErrorCode PCApply_BDDC(PC pc,Vec r,Vec z)
1748 {
1749   PC_IS             *pcis = (PC_IS*)(pc->data);
1750   PC_BDDC           *pcbddc = (PC_BDDC*)(pc->data);
1751   PetscInt          n_B = pcis->n_B, n_D = pcis->n - n_B;
1752   PetscErrorCode    ierr;
1753   const PetscScalar one = 1.0;
1754   const PetscScalar m_one = -1.0;
1755   const PetscScalar zero = 0.0;
1756 
1757 /* This code is similar to that provided in nn.c for PCNN
1758    NN interface preconditioner changed to BDDC
1759    Added support for M_3 preconditioner in the reference article (code is active if pcbddc->switch_static == PETSC_TRUE) */
1760 
1761   PetscFunctionBegin;
1762   ierr = PetscCitationsRegister(citation,&cited);CHKERRQ(ierr);
1763   if (pcbddc->ChangeOfBasisMatrix) {
1764     Vec swap;
1765 
1766     ierr = MatMultTranspose(pcbddc->ChangeOfBasisMatrix,r,pcbddc->work_change);CHKERRQ(ierr);
1767     swap = pcbddc->work_change;
1768     pcbddc->work_change = r;
1769     r = swap;
1770     /* save rhs so that we don't need to apply the change of basis for the exact dirichlet trick in PreSolve */
1771     if (pcbddc->benign_apply_coarse_only && pcbddc->use_exact_dirichlet_trick && pcbddc->change_interior) {
1772       ierr = VecCopy(r,pcis->vec1_global);CHKERRQ(ierr);
1773       ierr = VecLockPush(pcis->vec1_global);CHKERRQ(ierr);
1774     }
1775   }
1776   if (pcbddc->benign_have_null) { /* get p0 from r */
1777     ierr = PCBDDCBenignGetOrSetP0(pc,r,PETSC_TRUE);CHKERRQ(ierr);
1778   }
1779   if (!pcbddc->exact_dirichlet_trick_app && !pcbddc->benign_apply_coarse_only) {
1780     ierr = VecCopy(r,z);CHKERRQ(ierr);
1781     /* First Dirichlet solve */
1782     ierr = VecScatterBegin(pcis->global_to_D,r,pcis->vec1_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1783     ierr = VecScatterEnd(pcis->global_to_D,r,pcis->vec1_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1784     /*
1785       Assembling right hand side for BDDC operator
1786       - pcis->vec1_D for the Dirichlet part (if needed, i.e. pcbddc->switch_static == PETSC_TRUE)
1787       - pcis->vec1_B the interface part of the global vector z
1788     */
1789     if (n_D) {
1790       ierr = KSPSolve(pcbddc->ksp_D,pcis->vec1_D,pcis->vec2_D);CHKERRQ(ierr);
1791       ierr = VecScale(pcis->vec2_D,m_one);CHKERRQ(ierr);
1792       if (pcbddc->switch_static) {
1793         Mat_IS *matis = (Mat_IS*)(pc->mat->data);
1794 
1795         ierr = VecSet(pcis->vec1_N,0.);CHKERRQ(ierr);
1796         ierr = VecScatterBegin(pcis->N_to_D,pcis->vec2_D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1797         ierr = VecScatterEnd(pcis->N_to_D,pcis->vec2_D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1798         if (!pcbddc->switch_static_change) {
1799           ierr = MatMult(matis->A,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1800         } else {
1801           ierr = MatMult(pcbddc->switch_static_change,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1802           ierr = MatMult(matis->A,pcis->vec2_N,pcis->vec1_N);CHKERRQ(ierr);
1803           ierr = MatMultTranspose(pcbddc->switch_static_change,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1804         }
1805         ierr = VecScatterBegin(pcis->N_to_D,pcis->vec2_N,pcis->vec1_D,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1806         ierr = VecScatterEnd(pcis->N_to_D,pcis->vec2_N,pcis->vec1_D,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1807         ierr = VecScatterBegin(pcis->N_to_B,pcis->vec2_N,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1808         ierr = VecScatterEnd(pcis->N_to_B,pcis->vec2_N,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1809       } else {
1810         ierr = MatMult(pcis->A_BI,pcis->vec2_D,pcis->vec1_B);CHKERRQ(ierr);
1811       }
1812     } else {
1813       ierr = VecSet(pcis->vec1_B,zero);CHKERRQ(ierr);
1814     }
1815     ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,z,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1816     ierr = VecScatterEnd(pcis->global_to_B,pcis->vec1_B,z,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1817     ierr = PCBDDCScalingRestriction(pc,z,pcis->vec1_B);CHKERRQ(ierr);
1818   } else {
1819     if (!pcbddc->benign_apply_coarse_only) {
1820       ierr = PCBDDCScalingRestriction(pc,r,pcis->vec1_B);CHKERRQ(ierr);
1821     }
1822   }
1823 
1824   /* Apply interface preconditioner
1825      input/output vecs: pcis->vec1_B and pcis->vec1_D */
1826   ierr = PCBDDCApplyInterfacePreconditioner(pc,PETSC_FALSE);CHKERRQ(ierr);
1827 
1828   /* Apply transpose of partition of unity operator */
1829   ierr = PCBDDCScalingExtension(pc,pcis->vec1_B,z);CHKERRQ(ierr);
1830 
1831   /* Second Dirichlet solve and assembling of output */
1832   ierr = VecScatterBegin(pcis->global_to_B,z,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1833   ierr = VecScatterEnd(pcis->global_to_B,z,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1834   if (n_B) {
1835     if (pcbddc->switch_static) {
1836       Mat_IS *matis = (Mat_IS*)(pc->mat->data);
1837 
1838       ierr = VecScatterBegin(pcis->N_to_D,pcis->vec1_D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1839       ierr = VecScatterEnd(pcis->N_to_D,pcis->vec1_D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1840       ierr = VecScatterBegin(pcis->N_to_B,pcis->vec1_B,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1841       ierr = VecScatterEnd(pcis->N_to_B,pcis->vec1_B,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1842       if (!pcbddc->switch_static_change) {
1843         ierr = MatMult(matis->A,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1844       } else {
1845         ierr = MatMult(pcbddc->switch_static_change,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1846         ierr = MatMult(matis->A,pcis->vec2_N,pcis->vec1_N);CHKERRQ(ierr);
1847         ierr = MatMultTranspose(pcbddc->switch_static_change,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1848       }
1849       ierr = VecScatterBegin(pcis->N_to_D,pcis->vec2_N,pcis->vec3_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1850       ierr = VecScatterEnd(pcis->N_to_D,pcis->vec2_N,pcis->vec3_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1851     } else {
1852       ierr = MatMult(pcis->A_IB,pcis->vec1_B,pcis->vec3_D);CHKERRQ(ierr);
1853     }
1854   } else if (pcbddc->switch_static) { /* n_B is zero */
1855     Mat_IS *matis = (Mat_IS*)(pc->mat->data);
1856 
1857     if (!pcbddc->switch_static_change) {
1858       ierr = MatMult(matis->A,pcis->vec1_D,pcis->vec3_D);CHKERRQ(ierr);
1859     } else {
1860       ierr = MatMult(pcbddc->switch_static_change,pcis->vec1_D,pcis->vec1_N);CHKERRQ(ierr);
1861       ierr = MatMult(matis->A,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1862       ierr = MatMultTranspose(pcbddc->switch_static_change,pcis->vec2_N,pcis->vec3_D);CHKERRQ(ierr);
1863     }
1864   }
1865   ierr = KSPSolve(pcbddc->ksp_D,pcis->vec3_D,pcis->vec4_D);CHKERRQ(ierr);
1866 
1867   if (!pcbddc->exact_dirichlet_trick_app && !pcbddc->benign_apply_coarse_only) {
1868     if (pcbddc->switch_static) {
1869       ierr = VecAXPBYPCZ(pcis->vec2_D,m_one,one,m_one,pcis->vec4_D,pcis->vec1_D);CHKERRQ(ierr);
1870     } else {
1871       ierr = VecAXPBY(pcis->vec2_D,m_one,m_one,pcis->vec4_D);CHKERRQ(ierr);
1872     }
1873     ierr = VecScatterBegin(pcis->global_to_D,pcis->vec2_D,z,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1874     ierr = VecScatterEnd(pcis->global_to_D,pcis->vec2_D,z,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1875   } else {
1876     if (pcbddc->switch_static) {
1877       ierr = VecAXPBY(pcis->vec4_D,one,m_one,pcis->vec1_D);CHKERRQ(ierr);
1878     } else {
1879       ierr = VecScale(pcis->vec4_D,m_one);CHKERRQ(ierr);
1880     }
1881     ierr = VecScatterBegin(pcis->global_to_D,pcis->vec4_D,z,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1882     ierr = VecScatterEnd(pcis->global_to_D,pcis->vec4_D,z,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1883   }
1884   if (pcbddc->benign_have_null) { /* set p0 (computed in PCBDDCApplyInterface) */
1885     if (pcbddc->benign_apply_coarse_only) {
1886       ierr = PetscMemzero(pcbddc->benign_p0,pcbddc->benign_n*sizeof(PetscScalar));CHKERRQ(ierr);
1887     }
1888     ierr = PCBDDCBenignGetOrSetP0(pc,z,PETSC_FALSE);CHKERRQ(ierr);
1889   }
1890 
1891   if (pcbddc->ChangeOfBasisMatrix) {
1892     pcbddc->work_change = r;
1893     ierr = VecCopy(z,pcbddc->work_change);CHKERRQ(ierr);
1894     ierr = MatMult(pcbddc->ChangeOfBasisMatrix,pcbddc->work_change,z);CHKERRQ(ierr);
1895   }
1896   PetscFunctionReturn(0);
1897 }
1898 
1899 /*
1900    PCApplyTranspose_BDDC - Applies the transpose of the BDDC operator to a vector.
1901 
1902    Input Parameters:
1903 +  pc - the preconditioner context
1904 -  r - input vector (global)
1905 
1906    Output Parameter:
1907 .  z - output vector (global)
1908 
1909    Application Interface Routine: PCApplyTranspose()
1910  */
1911 PetscErrorCode PCApplyTranspose_BDDC(PC pc,Vec r,Vec z)
1912 {
1913   PC_IS             *pcis = (PC_IS*)(pc->data);
1914   PC_BDDC           *pcbddc = (PC_BDDC*)(pc->data);
1915   PetscInt          n_B = pcis->n_B, n_D = pcis->n - n_B;
1916   PetscErrorCode    ierr;
1917   const PetscScalar one = 1.0;
1918   const PetscScalar m_one = -1.0;
1919   const PetscScalar zero = 0.0;
1920 
1921   PetscFunctionBegin;
1922   ierr = PetscCitationsRegister(citation,&cited);CHKERRQ(ierr);
1923   if (pcbddc->ChangeOfBasisMatrix) {
1924     Vec swap;
1925 
1926     ierr = MatMultTranspose(pcbddc->ChangeOfBasisMatrix,r,pcbddc->work_change);CHKERRQ(ierr);
1927     swap = pcbddc->work_change;
1928     pcbddc->work_change = r;
1929     r = swap;
1930     /* save rhs so that we don't need to apply the change of basis for the exact dirichlet trick in PreSolve */
1931     if (pcbddc->benign_apply_coarse_only && pcbddc->exact_dirichlet_trick_app && pcbddc->change_interior) {
1932       ierr = VecCopy(r,pcis->vec1_global);CHKERRQ(ierr);
1933       ierr = VecLockPush(pcis->vec1_global);CHKERRQ(ierr);
1934     }
1935   }
1936   if (pcbddc->benign_have_null) { /* get p0 from r */
1937     ierr = PCBDDCBenignGetOrSetP0(pc,r,PETSC_TRUE);CHKERRQ(ierr);
1938   }
1939   if (!pcbddc->exact_dirichlet_trick_app && !pcbddc->benign_apply_coarse_only) {
1940     ierr = VecCopy(r,z);CHKERRQ(ierr);
1941     /* First Dirichlet solve */
1942     ierr = VecScatterBegin(pcis->global_to_D,r,pcis->vec1_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1943     ierr = VecScatterEnd(pcis->global_to_D,r,pcis->vec1_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1944     /*
1945       Assembling right hand side for BDDC operator
1946       - pcis->vec1_D for the Dirichlet part (if needed, i.e. pcbddc->switch_static == PETSC_TRUE)
1947       - pcis->vec1_B the interface part of the global vector z
1948     */
1949     if (n_D) {
1950       ierr = KSPSolveTranspose(pcbddc->ksp_D,pcis->vec1_D,pcis->vec2_D);CHKERRQ(ierr);
1951       ierr = VecScale(pcis->vec2_D,m_one);CHKERRQ(ierr);
1952       if (pcbddc->switch_static) {
1953         Mat_IS *matis = (Mat_IS*)(pc->mat->data);
1954 
1955         ierr = VecSet(pcis->vec1_N,0.);CHKERRQ(ierr);
1956         ierr = VecScatterBegin(pcis->N_to_D,pcis->vec2_D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1957         ierr = VecScatterEnd(pcis->N_to_D,pcis->vec2_D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1958         if (!pcbddc->switch_static_change) {
1959           ierr = MatMultTranspose(matis->A,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1960         } else {
1961           ierr = MatMult(pcbddc->switch_static_change,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1962           ierr = MatMultTranspose(matis->A,pcis->vec2_N,pcis->vec1_N);CHKERRQ(ierr);
1963           ierr = MatMultTranspose(pcbddc->switch_static_change,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
1964         }
1965         ierr = VecScatterBegin(pcis->N_to_D,pcis->vec2_N,pcis->vec1_D,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1966         ierr = VecScatterEnd(pcis->N_to_D,pcis->vec2_N,pcis->vec1_D,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1967         ierr = VecScatterBegin(pcis->N_to_B,pcis->vec2_N,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1968         ierr = VecScatterEnd(pcis->N_to_B,pcis->vec2_N,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1969       } else {
1970         ierr = MatMultTranspose(pcis->A_IB,pcis->vec2_D,pcis->vec1_B);CHKERRQ(ierr);
1971       }
1972     } else {
1973       ierr = VecSet(pcis->vec1_B,zero);CHKERRQ(ierr);
1974     }
1975     ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,z,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1976     ierr = VecScatterEnd(pcis->global_to_B,pcis->vec1_B,z,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1977     ierr = PCBDDCScalingRestriction(pc,z,pcis->vec1_B);CHKERRQ(ierr);
1978   } else {
1979     ierr = PCBDDCScalingRestriction(pc,r,pcis->vec1_B);CHKERRQ(ierr);
1980   }
1981 
1982   /* Apply interface preconditioner
1983      input/output vecs: pcis->vec1_B and pcis->vec1_D */
1984   ierr = PCBDDCApplyInterfacePreconditioner(pc,PETSC_TRUE);CHKERRQ(ierr);
1985 
1986   /* Apply transpose of partition of unity operator */
1987   ierr = PCBDDCScalingExtension(pc,pcis->vec1_B,z);CHKERRQ(ierr);
1988 
1989   /* Second Dirichlet solve and assembling of output */
1990   ierr = VecScatterBegin(pcis->global_to_B,z,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1991   ierr = VecScatterEnd(pcis->global_to_B,z,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1992   if (n_B) {
1993     if (pcbddc->switch_static) {
1994       Mat_IS *matis = (Mat_IS*)(pc->mat->data);
1995 
1996       ierr = VecScatterBegin(pcis->N_to_D,pcis->vec1_D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1997       ierr = VecScatterEnd(pcis->N_to_D,pcis->vec1_D,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1998       ierr = VecScatterBegin(pcis->N_to_B,pcis->vec1_B,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1999       ierr = VecScatterEnd(pcis->N_to_B,pcis->vec1_B,pcis->vec1_N,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2000       if (!pcbddc->switch_static_change) {
2001         ierr = MatMultTranspose(matis->A,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
2002       } else {
2003         ierr = MatMult(pcbddc->switch_static_change,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
2004         ierr = MatMultTranspose(matis->A,pcis->vec2_N,pcis->vec1_N);CHKERRQ(ierr);
2005         ierr = MatMultTranspose(pcbddc->switch_static_change,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
2006       }
2007       ierr = VecScatterBegin(pcis->N_to_D,pcis->vec2_N,pcis->vec3_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2008       ierr = VecScatterEnd(pcis->N_to_D,pcis->vec2_N,pcis->vec3_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2009     } else {
2010       ierr = MatMultTranspose(pcis->A_BI,pcis->vec1_B,pcis->vec3_D);CHKERRQ(ierr);
2011     }
2012   } else if (pcbddc->switch_static) { /* n_B is zero */
2013     Mat_IS *matis = (Mat_IS*)(pc->mat->data);
2014 
2015     if (!pcbddc->switch_static_change) {
2016       ierr = MatMultTranspose(matis->A,pcis->vec1_D,pcis->vec3_D);CHKERRQ(ierr);
2017     } else {
2018       ierr = MatMult(pcbddc->switch_static_change,pcis->vec1_D,pcis->vec1_N);CHKERRQ(ierr);
2019       ierr = MatMultTranspose(matis->A,pcis->vec1_N,pcis->vec2_N);CHKERRQ(ierr);
2020       ierr = MatMultTranspose(pcbddc->switch_static_change,pcis->vec2_N,pcis->vec3_D);CHKERRQ(ierr);
2021     }
2022   }
2023   ierr = KSPSolveTranspose(pcbddc->ksp_D,pcis->vec3_D,pcis->vec4_D);CHKERRQ(ierr);
2024   if (!pcbddc->exact_dirichlet_trick_app && !pcbddc->benign_apply_coarse_only) {
2025     if (pcbddc->switch_static) {
2026       ierr = VecAXPBYPCZ(pcis->vec2_D,m_one,one,m_one,pcis->vec4_D,pcis->vec1_D);CHKERRQ(ierr);
2027     } else {
2028       ierr = VecAXPBY(pcis->vec2_D,m_one,m_one,pcis->vec4_D);CHKERRQ(ierr);
2029     }
2030     ierr = VecScatterBegin(pcis->global_to_D,pcis->vec2_D,z,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2031     ierr = VecScatterEnd(pcis->global_to_D,pcis->vec2_D,z,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2032   } else {
2033     if (pcbddc->switch_static) {
2034       ierr = VecAXPBY(pcis->vec4_D,one,m_one,pcis->vec1_D);CHKERRQ(ierr);
2035     } else {
2036       ierr = VecScale(pcis->vec4_D,m_one);CHKERRQ(ierr);
2037     }
2038     ierr = VecScatterBegin(pcis->global_to_D,pcis->vec4_D,z,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2039     ierr = VecScatterEnd(pcis->global_to_D,pcis->vec4_D,z,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2040   }
2041   if (pcbddc->benign_have_null) { /* set p0 (computed in PCBDDCApplyInterface) */
2042     ierr = PCBDDCBenignGetOrSetP0(pc,z,PETSC_FALSE);CHKERRQ(ierr);
2043   }
2044   if (pcbddc->ChangeOfBasisMatrix) {
2045     pcbddc->work_change = r;
2046     ierr = VecCopy(z,pcbddc->work_change);CHKERRQ(ierr);
2047     ierr = MatMult(pcbddc->ChangeOfBasisMatrix,pcbddc->work_change,z);CHKERRQ(ierr);
2048   }
2049   PetscFunctionReturn(0);
2050 }
2051 
2052 PetscErrorCode PCReset_BDDC(PC pc)
2053 {
2054   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
2055   PC_IS          *pcis = (PC_IS*)pc->data;
2056   KSP            kspD,kspR,kspC;
2057   PetscErrorCode ierr;
2058 
2059   PetscFunctionBegin;
2060   /* free BDDC custom data  */
2061   ierr = PCBDDCResetCustomization(pc);CHKERRQ(ierr);
2062   /* destroy objects related to topography */
2063   ierr = PCBDDCResetTopography(pc);CHKERRQ(ierr);
2064   /* destroy objects for scaling operator */
2065   ierr = PCBDDCScalingDestroy(pc);CHKERRQ(ierr);
2066   /* free solvers stuff */
2067   ierr = PCBDDCResetSolvers(pc);CHKERRQ(ierr);
2068   /* free global vectors needed in presolve */
2069   ierr = VecDestroy(&pcbddc->temp_solution);CHKERRQ(ierr);
2070   ierr = VecDestroy(&pcbddc->original_rhs);CHKERRQ(ierr);
2071   /* free data created by PCIS */
2072   ierr = PCISDestroy(pc);CHKERRQ(ierr);
2073 
2074   /* restore defaults */
2075   kspD = pcbddc->ksp_D;
2076   kspR = pcbddc->ksp_R;
2077   kspC = pcbddc->coarse_ksp;
2078   ierr = PetscMemzero(pc->data,sizeof(*pcbddc));CHKERRQ(ierr);
2079   pcis->n_neigh                     = -1;
2080   pcis->scaling_factor              = 1.0;
2081   pcis->reusesubmatrices            = PETSC_TRUE;
2082   pcbddc->use_local_adj             = PETSC_TRUE;
2083   pcbddc->use_vertices              = PETSC_TRUE;
2084   pcbddc->use_edges                 = PETSC_TRUE;
2085   pcbddc->symmetric_primal          = PETSC_TRUE;
2086   pcbddc->vertex_size               = 1;
2087   pcbddc->recompute_topography      = PETSC_TRUE;
2088   pcbddc->coarse_size               = -1;
2089   pcbddc->use_exact_dirichlet_trick = PETSC_TRUE;
2090   pcbddc->coarsening_ratio          = 8;
2091   pcbddc->coarse_eqs_per_proc       = 1;
2092   pcbddc->benign_compute_correction = PETSC_TRUE;
2093   pcbddc->nedfield                  = -1;
2094   pcbddc->nedglobal                 = PETSC_TRUE;
2095   pcbddc->graphmaxcount             = PETSC_MAX_INT;
2096   pcbddc->sub_schurs_layers         = -1;
2097   pcbddc->ksp_D                     = kspD;
2098   pcbddc->ksp_R                     = kspR;
2099   pcbddc->coarse_ksp                = kspC;
2100   PetscFunctionReturn(0);
2101 }
2102 
2103 PetscErrorCode PCDestroy_BDDC(PC pc)
2104 {
2105   PC_BDDC        *pcbddc = (PC_BDDC*)pc->data;
2106   PetscErrorCode ierr;
2107 
2108   PetscFunctionBegin;
2109   ierr = PCReset_BDDC(pc);CHKERRQ(ierr);
2110   ierr = KSPDestroy(&pcbddc->ksp_D);CHKERRQ(ierr);
2111   ierr = KSPDestroy(&pcbddc->ksp_R);CHKERRQ(ierr);
2112   ierr = KSPDestroy(&pcbddc->coarse_ksp);CHKERRQ(ierr);
2113   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDiscreteGradient_C",NULL);CHKERRQ(ierr);
2114   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDivergenceMat_C",NULL);CHKERRQ(ierr);
2115   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetChangeOfBasisMat_C",NULL);CHKERRQ(ierr);
2116   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetPrimalVerticesLocalIS_C",NULL);CHKERRQ(ierr);
2117   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetPrimalVerticesIS_C",NULL);CHKERRQ(ierr);
2118   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetCoarseningRatio_C",NULL);CHKERRQ(ierr);
2119   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetLevel_C",NULL);CHKERRQ(ierr);
2120   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetUseExactDirichlet_C",NULL);CHKERRQ(ierr);
2121   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetLevels_C",NULL);CHKERRQ(ierr);
2122   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDirichletBoundaries_C",NULL);CHKERRQ(ierr);
2123   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDirichletBoundariesLocal_C",NULL);CHKERRQ(ierr);
2124   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetNeumannBoundaries_C",NULL);CHKERRQ(ierr);
2125   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetNeumannBoundariesLocal_C",NULL);CHKERRQ(ierr);
2126   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCGetDirichletBoundaries_C",NULL);CHKERRQ(ierr);
2127   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCGetDirichletBoundariesLocal_C",NULL);CHKERRQ(ierr);
2128   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCGetNeumannBoundaries_C",NULL);CHKERRQ(ierr);
2129   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCGetNeumannBoundariesLocal_C",NULL);CHKERRQ(ierr);
2130   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDofsSplitting_C",NULL);CHKERRQ(ierr);
2131   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDofsSplittingLocal_C",NULL);CHKERRQ(ierr);
2132   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetLocalAdjacencyGraph_C",NULL);CHKERRQ(ierr);
2133   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCCreateFETIDPOperators_C",NULL);CHKERRQ(ierr);
2134   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCMatFETIDPGetRHS_C",NULL);CHKERRQ(ierr);
2135   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCMatFETIDPGetSolution_C",NULL);CHKERRQ(ierr);
2136   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCPreSolveChangeRHS_C",NULL);CHKERRQ(ierr);
2137   ierr = PetscFree(pc->data);CHKERRQ(ierr);
2138   PetscFunctionReturn(0);
2139 }
2140 
2141 static PetscErrorCode PCPreSolveChangeRHS_BDDC(PC pc, PetscBool* change)
2142 {
2143   PetscFunctionBegin;
2144   *change = PETSC_TRUE;
2145   PetscFunctionReturn(0);
2146 }
2147 
2148 static PetscErrorCode PCBDDCMatFETIDPGetRHS_BDDC(Mat fetidp_mat, Vec standard_rhs, Vec fetidp_flux_rhs)
2149 {
2150   FETIDPMat_ctx  mat_ctx;
2151   Vec            work;
2152   PC_IS*         pcis;
2153   PC_BDDC*       pcbddc;
2154   PetscErrorCode ierr;
2155 
2156   PetscFunctionBegin;
2157   ierr = MatShellGetContext(fetidp_mat,&mat_ctx);CHKERRQ(ierr);
2158   pcis = (PC_IS*)mat_ctx->pc->data;
2159   pcbddc = (PC_BDDC*)mat_ctx->pc->data;
2160 
2161   ierr = VecSet(fetidp_flux_rhs,0.0);CHKERRQ(ierr);
2162   /* copy rhs since we may change it during PCPreSolve_BDDC */
2163   if (!pcbddc->original_rhs) {
2164     ierr = VecDuplicate(pcis->vec1_global,&pcbddc->original_rhs);CHKERRQ(ierr);
2165   }
2166   if (mat_ctx->rhs_flip) {
2167     ierr = VecPointwiseMult(pcbddc->original_rhs,standard_rhs,mat_ctx->rhs_flip);CHKERRQ(ierr);
2168   } else {
2169     ierr = VecCopy(standard_rhs,pcbddc->original_rhs);CHKERRQ(ierr);
2170   }
2171   if (mat_ctx->g2g_p) {
2172     /* interface pressure rhs */
2173     ierr = VecScatterBegin(mat_ctx->g2g_p,fetidp_flux_rhs,pcbddc->original_rhs,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2174     ierr = VecScatterEnd(mat_ctx->g2g_p,fetidp_flux_rhs,pcbddc->original_rhs,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2175     ierr = VecScatterBegin(mat_ctx->g2g_p,standard_rhs,fetidp_flux_rhs,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2176     ierr = VecScatterEnd(mat_ctx->g2g_p,standard_rhs,fetidp_flux_rhs,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2177     if (!mat_ctx->rhs_flip) {
2178       ierr = VecScale(fetidp_flux_rhs,-1.);CHKERRQ(ierr);
2179     }
2180   }
2181   /*
2182      change of basis for physical rhs if needed
2183      It also changes the rhs in case of dirichlet boundaries
2184   */
2185   ierr = PCPreSolve_BDDC(mat_ctx->pc,NULL,pcbddc->original_rhs,NULL);CHKERRQ(ierr);
2186   if (pcbddc->ChangeOfBasisMatrix) {
2187     ierr = MatMultTranspose(pcbddc->ChangeOfBasisMatrix,pcbddc->original_rhs,pcbddc->work_change);CHKERRQ(ierr);
2188     work = pcbddc->work_change;
2189    } else {
2190     work = pcbddc->original_rhs;
2191   }
2192   /* store vectors for computation of fetidp final solution */
2193   ierr = VecScatterBegin(pcis->global_to_D,work,mat_ctx->temp_solution_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2194   ierr = VecScatterEnd(pcis->global_to_D,work,mat_ctx->temp_solution_D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2195   /* scale rhs since it should be unassembled */
2196   /* TODO use counter scaling? (also below) */
2197   ierr = VecScatterBegin(pcis->global_to_B,work,mat_ctx->temp_solution_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2198   ierr = VecScatterEnd(pcis->global_to_B,work,mat_ctx->temp_solution_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2199   /* Apply partition of unity */
2200   ierr = VecPointwiseMult(mat_ctx->temp_solution_B,pcis->D,mat_ctx->temp_solution_B);CHKERRQ(ierr);
2201   /* ierr = PCBDDCScalingRestriction(mat_ctx->pc,work,mat_ctx->temp_solution_B);CHKERRQ(ierr); */
2202   if (!pcbddc->switch_static) {
2203     /* compute partially subassembled Schur complement right-hand side */
2204     ierr = KSPSolve(pcbddc->ksp_D,mat_ctx->temp_solution_D,pcis->vec1_D);CHKERRQ(ierr);
2205     ierr = MatMult(pcis->A_BI,pcis->vec1_D,pcis->vec1_B);CHKERRQ(ierr);
2206     ierr = VecAXPY(mat_ctx->temp_solution_B,-1.0,pcis->vec1_B);CHKERRQ(ierr);
2207     ierr = VecSet(work,0.0);CHKERRQ(ierr);
2208     ierr = VecScatterBegin(pcis->global_to_B,mat_ctx->temp_solution_B,work,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2209     ierr = VecScatterEnd(pcis->global_to_B,mat_ctx->temp_solution_B,work,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2210     /* ierr = PCBDDCScalingRestriction(mat_ctx->pc,work,mat_ctx->temp_solution_B);CHKERRQ(ierr); */
2211     ierr = VecScatterBegin(pcis->global_to_B,work,mat_ctx->temp_solution_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2212     ierr = VecScatterEnd(pcis->global_to_B,work,mat_ctx->temp_solution_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2213     ierr = VecPointwiseMult(mat_ctx->temp_solution_B,pcis->D,mat_ctx->temp_solution_B);CHKERRQ(ierr);
2214   }
2215   /* BDDC rhs */
2216   ierr = VecCopy(mat_ctx->temp_solution_B,pcis->vec1_B);CHKERRQ(ierr);
2217   if (pcbddc->switch_static) {
2218     ierr = VecCopy(mat_ctx->temp_solution_D,pcis->vec1_D);CHKERRQ(ierr);
2219   }
2220   /* apply BDDC */
2221   ierr = PetscMemzero(pcbddc->benign_p0,pcbddc->benign_n*sizeof(PetscScalar));CHKERRQ(ierr);
2222   ierr = PCBDDCApplyInterfacePreconditioner(mat_ctx->pc,PETSC_FALSE);CHKERRQ(ierr);
2223   ierr = PetscMemzero(pcbddc->benign_p0,pcbddc->benign_n*sizeof(PetscScalar));CHKERRQ(ierr);
2224 
2225   /* Application of B_delta and assembling of rhs for fetidp fluxes */
2226   ierr = MatMult(mat_ctx->B_delta,pcis->vec1_B,mat_ctx->lambda_local);CHKERRQ(ierr);
2227   ierr = VecScatterBegin(mat_ctx->l2g_lambda,mat_ctx->lambda_local,fetidp_flux_rhs,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2228   ierr = VecScatterEnd(mat_ctx->l2g_lambda,mat_ctx->lambda_local,fetidp_flux_rhs,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2229   /* Add contribution to interface pressures */
2230   if (mat_ctx->l2g_p) {
2231     ierr = MatMult(mat_ctx->B_BB,pcis->vec1_B,mat_ctx->vP);CHKERRQ(ierr);
2232     if (pcbddc->switch_static) {
2233       ierr = MatMultAdd(mat_ctx->B_BI,pcis->vec1_D,mat_ctx->vP,mat_ctx->vP);CHKERRQ(ierr);
2234     }
2235     ierr = VecScatterBegin(mat_ctx->l2g_p,mat_ctx->vP,fetidp_flux_rhs,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2236     ierr = VecScatterEnd(mat_ctx->l2g_p,mat_ctx->vP,fetidp_flux_rhs,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2237   }
2238   PetscFunctionReturn(0);
2239 }
2240 
2241 /*@
2242  PCBDDCMatFETIDPGetRHS - Compute the right-hand side for FETI-DP linear system using the physical right-hand side
2243 
2244    Collective
2245 
2246    Input Parameters:
2247 +  fetidp_mat      - the FETI-DP matrix object obtained by a call to PCBDDCCreateFETIDPOperators
2248 -  standard_rhs    - the right-hand side of the original linear system
2249 
2250    Output Parameters:
2251 .  fetidp_flux_rhs - the right-hand side for the FETI-DP linear system
2252 
2253    Level: developer
2254 
2255    Notes:
2256 
2257 .seealso: PCBDDC, PCBDDCCreateFETIDPOperators, PCBDDCMatFETIDPGetSolution
2258 @*/
2259 PetscErrorCode PCBDDCMatFETIDPGetRHS(Mat fetidp_mat, Vec standard_rhs, Vec fetidp_flux_rhs)
2260 {
2261   FETIDPMat_ctx  mat_ctx;
2262   PetscErrorCode ierr;
2263 
2264   PetscFunctionBegin;
2265   PetscValidHeaderSpecific(fetidp_mat,MAT_CLASSID,1);
2266   PetscValidHeaderSpecific(standard_rhs,VEC_CLASSID,2);
2267   PetscValidHeaderSpecific(fetidp_flux_rhs,VEC_CLASSID,3);
2268   ierr = MatShellGetContext(fetidp_mat,&mat_ctx);CHKERRQ(ierr);
2269   ierr = PetscUseMethod(mat_ctx->pc,"PCBDDCMatFETIDPGetRHS_C",(Mat,Vec,Vec),(fetidp_mat,standard_rhs,fetidp_flux_rhs));CHKERRQ(ierr);
2270   PetscFunctionReturn(0);
2271 }
2272 
2273 static PetscErrorCode PCBDDCMatFETIDPGetSolution_BDDC(Mat fetidp_mat, Vec fetidp_flux_sol, Vec standard_sol)
2274 {
2275   FETIDPMat_ctx  mat_ctx;
2276   PC_IS*         pcis;
2277   PC_BDDC*       pcbddc;
2278   PetscErrorCode ierr;
2279   Vec            work;
2280 
2281   PetscFunctionBegin;
2282   ierr = MatShellGetContext(fetidp_mat,&mat_ctx);CHKERRQ(ierr);
2283   pcis = (PC_IS*)mat_ctx->pc->data;
2284   pcbddc = (PC_BDDC*)mat_ctx->pc->data;
2285 
2286   /* apply B_delta^T */
2287   ierr = VecSet(pcis->vec1_B,0.);CHKERRQ(ierr);
2288   ierr = VecScatterBegin(mat_ctx->l2g_lambda,fetidp_flux_sol,mat_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2289   ierr = VecScatterEnd(mat_ctx->l2g_lambda,fetidp_flux_sol,mat_ctx->lambda_local,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2290   ierr = MatMultTranspose(mat_ctx->B_delta,mat_ctx->lambda_local,pcis->vec1_B);CHKERRQ(ierr);
2291   if (mat_ctx->l2g_p) {
2292     ierr = VecScatterBegin(mat_ctx->l2g_p,fetidp_flux_sol,mat_ctx->vP,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2293     ierr = VecScatterEnd(mat_ctx->l2g_p,fetidp_flux_sol,mat_ctx->vP,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2294     ierr = MatMultAdd(mat_ctx->Bt_BB,mat_ctx->vP,pcis->vec1_B,pcis->vec1_B);CHKERRQ(ierr);
2295   }
2296 
2297   /* compute rhs for BDDC application */
2298   ierr = VecAYPX(pcis->vec1_B,-1.0,mat_ctx->temp_solution_B);CHKERRQ(ierr);
2299   if (pcbddc->switch_static) {
2300     ierr = VecCopy(mat_ctx->temp_solution_D,pcis->vec1_D);CHKERRQ(ierr);
2301     if (mat_ctx->l2g_p) {
2302       ierr = VecScale(mat_ctx->vP,-1.);CHKERRQ(ierr);
2303       ierr = MatMultAdd(mat_ctx->Bt_BI,mat_ctx->vP,pcis->vec1_D,pcis->vec1_D);CHKERRQ(ierr);
2304     }
2305   }
2306 
2307   /* apply BDDC */
2308   ierr = PetscMemzero(pcbddc->benign_p0,pcbddc->benign_n*sizeof(PetscScalar));CHKERRQ(ierr);
2309   ierr = PCBDDCApplyInterfacePreconditioner(mat_ctx->pc,PETSC_FALSE);CHKERRQ(ierr);
2310 
2311   /* put values into global vector */
2312   if (pcbddc->ChangeOfBasisMatrix) work = pcbddc->work_change;
2313   else work = standard_sol;
2314   ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,work,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2315   ierr = VecScatterEnd(pcis->global_to_B,pcis->vec1_B,work,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2316   if (!pcbddc->switch_static) {
2317     /* compute values into the interior if solved for the partially subassembled Schur complement */
2318     ierr = MatMult(pcis->A_IB,pcis->vec1_B,pcis->vec1_D);CHKERRQ(ierr);
2319     ierr = VecAYPX(pcis->vec1_D,-1.0,mat_ctx->temp_solution_D);CHKERRQ(ierr);
2320     ierr = KSPSolve(pcbddc->ksp_D,pcis->vec1_D,pcis->vec1_D);CHKERRQ(ierr);
2321   }
2322 
2323   ierr = VecScatterBegin(pcis->global_to_D,pcis->vec1_D,work,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2324   ierr = VecScatterEnd(pcis->global_to_D,pcis->vec1_D,work,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2325   /* add p0 solution to final solution */
2326   ierr = PCBDDCBenignGetOrSetP0(mat_ctx->pc,work,PETSC_FALSE);CHKERRQ(ierr);
2327   if (pcbddc->ChangeOfBasisMatrix) {
2328     ierr = MatMult(pcbddc->ChangeOfBasisMatrix,work,standard_sol);CHKERRQ(ierr);
2329   }
2330   ierr = PCPostSolve_BDDC(mat_ctx->pc,NULL,NULL,standard_sol);CHKERRQ(ierr);
2331   if (mat_ctx->g2g_p) {
2332     ierr = VecScatterBegin(mat_ctx->g2g_p,fetidp_flux_sol,standard_sol,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2333     ierr = VecScatterEnd(mat_ctx->g2g_p,fetidp_flux_sol,standard_sol,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2334   }
2335   PetscFunctionReturn(0);
2336 }
2337 
2338 /*@
2339  PCBDDCMatFETIDPGetSolution - Compute the physical solution using the solution of the FETI-DP linear system
2340 
2341    Collective
2342 
2343    Input Parameters:
2344 +  fetidp_mat      - the FETI-DP matrix obtained by a call to PCBDDCCreateFETIDPOperators
2345 -  fetidp_flux_sol - the solution of the FETI-DP linear system
2346 
2347    Output Parameters:
2348 .  standard_sol    - the solution defined on the physical domain
2349 
2350    Level: developer
2351 
2352    Notes:
2353 
2354 .seealso: PCBDDC, PCBDDCCreateFETIDPOperators, PCBDDCMatFETIDPGetRHS
2355 @*/
2356 PetscErrorCode PCBDDCMatFETIDPGetSolution(Mat fetidp_mat, Vec fetidp_flux_sol, Vec standard_sol)
2357 {
2358   FETIDPMat_ctx  mat_ctx;
2359   PetscErrorCode ierr;
2360 
2361   PetscFunctionBegin;
2362   PetscValidHeaderSpecific(fetidp_mat,MAT_CLASSID,1);
2363   PetscValidHeaderSpecific(fetidp_flux_sol,VEC_CLASSID,2);
2364   PetscValidHeaderSpecific(standard_sol,VEC_CLASSID,3);
2365   ierr = MatShellGetContext(fetidp_mat,&mat_ctx);CHKERRQ(ierr);
2366   ierr = PetscUseMethod(mat_ctx->pc,"PCBDDCMatFETIDPGetSolution_C",(Mat,Vec,Vec),(fetidp_mat,fetidp_flux_sol,standard_sol));CHKERRQ(ierr);
2367   PetscFunctionReturn(0);
2368 }
2369 
2370 static PetscErrorCode PCBDDCCreateFETIDPOperators_BDDC(PC pc, PetscBool fully_redundant, const char* prefix, Mat *fetidp_mat, PC *fetidp_pc)
2371 {
2372 
2373   FETIDPMat_ctx  fetidpmat_ctx;
2374   Mat            newmat;
2375   FETIDPPC_ctx   fetidppc_ctx;
2376   PC             newpc;
2377   MPI_Comm       comm;
2378   PetscErrorCode ierr;
2379 
2380   PetscFunctionBegin;
2381   ierr = PetscObjectGetComm((PetscObject)pc,&comm);CHKERRQ(ierr);
2382   /* FETIDP linear matrix */
2383   ierr = PCBDDCCreateFETIDPMatContext(pc,&fetidpmat_ctx);CHKERRQ(ierr);
2384   fetidpmat_ctx->fully_redundant = fully_redundant;
2385   ierr = PCBDDCSetupFETIDPMatContext(fetidpmat_ctx);CHKERRQ(ierr);
2386   ierr = MatCreateShell(comm,fetidpmat_ctx->n,fetidpmat_ctx->n,fetidpmat_ctx->N,fetidpmat_ctx->N,fetidpmat_ctx,&newmat);CHKERRQ(ierr);
2387   ierr = MatShellSetOperation(newmat,MATOP_MULT,(void (*)(void))FETIDPMatMult);CHKERRQ(ierr);
2388   ierr = MatShellSetOperation(newmat,MATOP_MULT_TRANSPOSE,(void (*)(void))FETIDPMatMultTranspose);CHKERRQ(ierr);
2389   ierr = MatShellSetOperation(newmat,MATOP_DESTROY,(void (*)(void))PCBDDCDestroyFETIDPMat);CHKERRQ(ierr);
2390   ierr = MatSetOptionsPrefix(newmat,prefix);CHKERRQ(ierr);
2391   ierr = MatAppendOptionsPrefix(newmat,"fetidp_");CHKERRQ(ierr);
2392   ierr = MatSetUp(newmat);CHKERRQ(ierr);
2393   /* FETIDP preconditioner */
2394   ierr = PCBDDCCreateFETIDPPCContext(pc,&fetidppc_ctx);CHKERRQ(ierr);
2395   ierr = PCBDDCSetupFETIDPPCContext(newmat,fetidppc_ctx);CHKERRQ(ierr);
2396   ierr = PCCreate(comm,&newpc);CHKERRQ(ierr);
2397   ierr = PCSetOperators(newpc,newmat,newmat);CHKERRQ(ierr);
2398   ierr = PCSetOptionsPrefix(newpc,prefix);CHKERRQ(ierr);
2399   ierr = PCAppendOptionsPrefix(newpc,"fetidp_");CHKERRQ(ierr);
2400   if (!fetidpmat_ctx->l2g_lambda_only) {
2401     ierr = PCSetType(newpc,PCSHELL);CHKERRQ(ierr);
2402     ierr = PCShellSetContext(newpc,fetidppc_ctx);CHKERRQ(ierr);
2403     ierr = PCShellSetApply(newpc,FETIDPPCApply);CHKERRQ(ierr);
2404     ierr = PCShellSetApplyTranspose(newpc,FETIDPPCApplyTranspose);CHKERRQ(ierr);
2405     ierr = PCShellSetView(newpc,FETIDPPCView);CHKERRQ(ierr);
2406     ierr = PCShellSetDestroy(newpc,PCBDDCDestroyFETIDPPC);CHKERRQ(ierr);
2407   } else {
2408     KSP      *ksps;
2409     PC       lagpc;
2410     Mat      M,AM,PM;
2411     PetscInt nn;
2412 
2413     ierr = PetscObjectQuery((PetscObject)pc,"__KSPFETIDP_PPmat",(PetscObject*)&M);CHKERRQ(ierr);
2414     ierr = PCSetType(newpc,PCFIELDSPLIT);CHKERRQ(ierr);
2415     ierr = PCFieldSplitSetIS(newpc,"lag",fetidpmat_ctx->lagrange);CHKERRQ(ierr);
2416     ierr = PCFieldSplitSetIS(newpc,"p",fetidpmat_ctx->pressure);CHKERRQ(ierr);
2417     ierr = PCFieldSplitSetType(newpc,PC_COMPOSITE_SCHUR);CHKERRQ(ierr);
2418     ierr = PCFieldSplitSetSchurFactType(newpc,PC_FIELDSPLIT_SCHUR_FACT_DIAG);CHKERRQ(ierr);
2419     ierr = PCFieldSplitSetSchurPre(newpc,PC_FIELDSPLIT_SCHUR_PRE_USER,M);CHKERRQ(ierr);
2420     ierr = PCFieldSplitSetSchurScale(newpc,1.0);CHKERRQ(ierr);
2421     ierr = PCSetFromOptions(newpc);CHKERRQ(ierr);
2422     ierr = PCSetUp(newpc);CHKERRQ(ierr);
2423 
2424     /* set the solver for the (0,0) block */
2425     ierr = PCFieldSplitGetSubKSP(newpc,&nn,&ksps);CHKERRQ(ierr);
2426     ierr = PCCreate(comm,&lagpc);CHKERRQ(ierr);
2427     ierr = PCSetType(lagpc,PCSHELL);CHKERRQ(ierr);
2428     ierr = KSPGetOperators(ksps[0],&AM,&PM);CHKERRQ(ierr);
2429     ierr = PCSetOperators(lagpc,AM,PM);CHKERRQ(ierr);
2430     ierr = PCShellSetContext(lagpc,fetidppc_ctx);CHKERRQ(ierr);
2431     ierr = PCShellSetApply(lagpc,FETIDPPCApply);CHKERRQ(ierr);
2432     ierr = PCShellSetApplyTranspose(lagpc,FETIDPPCApplyTranspose);CHKERRQ(ierr);
2433     ierr = PCShellSetView(lagpc,FETIDPPCView);CHKERRQ(ierr);
2434     ierr = PCShellSetDestroy(lagpc,PCBDDCDestroyFETIDPPC);CHKERRQ(ierr);
2435     ierr = KSPSetPC(ksps[0],lagpc);CHKERRQ(ierr);
2436     ierr = PCDestroy(&lagpc);CHKERRQ(ierr);
2437     ierr = PetscFree(ksps);CHKERRQ(ierr);
2438   }
2439   /* return pointers for objects created */
2440   *fetidp_mat = newmat;
2441   *fetidp_pc = newpc;
2442   PetscFunctionReturn(0);
2443 }
2444 
2445 /*@C
2446  PCBDDCCreateFETIDPOperators - Create FETI-DP operators
2447 
2448    Collective
2449 
2450    Input Parameters:
2451 +  pc - the BDDC preconditioning context (setup should have been called before)
2452 .  fully_redundant - true for a fully redundant set of Lagrange multipliers
2453 -  prefix - optional options database prefix for the objects to be created (can be NULL)
2454 
2455    Output Parameters:
2456 +  fetidp_mat - shell FETI-DP matrix object
2457 -  fetidp_pc  - shell Dirichlet preconditioner for FETI-DP matrix
2458 
2459    Level: developer
2460 
2461    Notes:
2462      Currently the only operations provided for FETI-DP matrix are MatMult and MatMultTranspose
2463 
2464 .seealso: PCBDDC, PCBDDCMatFETIDPGetRHS, PCBDDCMatFETIDPGetSolution
2465 @*/
2466 PetscErrorCode PCBDDCCreateFETIDPOperators(PC pc, PetscBool fully_redundant, const char *prefix, Mat *fetidp_mat, PC *fetidp_pc)
2467 {
2468   PetscErrorCode ierr;
2469 
2470   PetscFunctionBegin;
2471   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
2472   if (pc->setupcalled) {
2473     ierr = PetscUseMethod(pc,"PCBDDCCreateFETIDPOperators_C",(PC,PetscBool,const char*,Mat*,PC*),(pc,fully_redundant,prefix,fetidp_mat,fetidp_pc));CHKERRQ(ierr);
2474   } else SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"You must call PCSetup_BDDC() first \n");
2475   PetscFunctionReturn(0);
2476 }
2477 /* -------------------------------------------------------------------------- */
2478 /*MC
2479    PCBDDC - Balancing Domain Decomposition by Constraints.
2480 
2481    An implementation of the BDDC preconditioner based on
2482 
2483 .vb
2484    [1] C. R. Dohrmann. "An approximate BDDC preconditioner", Numerical Linear Algebra with Applications Volume 14, Issue 2, pages 149-168, March 2007
2485    [2] A. Klawonn and O. B. Widlund. "Dual-Primal FETI Methods for Linear Elasticity", http://cs.nyu.edu/csweb/Research/TechReports/TR2004-855/TR2004-855.pdf
2486    [3] J. Mandel, B. Sousedik, C. R. Dohrmann. "Multispace and Multilevel BDDC", http://arxiv.org/abs/0712.3977
2487    [4] C. Pechstein and C. R. Dohrmann. "Modern domain decomposition methods BDDC, deluxe scaling, and an algebraic approach", Seminar talk, Linz, December 2013, http://people.ricam.oeaw.ac.at/c.pechstein/pechstein-bddc2013.pdf
2488 .ve
2489 
2490    The matrix to be preconditioned (Pmat) must be of type MATIS.
2491 
2492    Currently works with MATIS matrices with local matrices of type MATSEQAIJ, MATSEQBAIJ or MATSEQSBAIJ, either with real or complex numbers.
2493 
2494    It also works with unsymmetric and indefinite problems.
2495 
2496    Unlike 'conventional' interface preconditioners, PCBDDC iterates over all degrees of freedom, not just those on the interface. This allows the use of approximate solvers on the subdomains.
2497 
2498    Approximate local solvers are automatically adapted (see [1]) if the user has attached a nullspace object to the subdomain matrices, and informed BDDC of using approximate solvers (via the command line).
2499 
2500    Boundary nodes are split in vertices, edges and faces classes using information from the local to global mapping of dofs and the local connectivity graph of nodes. The latter can be customized by using PCBDDCSetLocalAdjacencyGraph()
2501    Additional information on dofs can be provided by using PCBDDCSetDofsSplitting(), PCBDDCSetDirichletBoundaries(), PCBDDCSetNeumannBoundaries(), and PCBDDCSetPrimalVerticesIS() and their local counterparts.
2502 
2503    Constraints can be customized by attaching a MatNullSpace object to the MATIS matrix via MatSetNearNullSpace(). Non-singular modes are retained via SVD.
2504 
2505    Change of basis is performed similarly to [2] when requested. When more than one constraint is present on a single connected component (i.e. an edge or a face), a robust method based on local QR factorizations is used.
2506    User defined change of basis can be passed to PCBDDC by using PCBDDCSetChangeOfBasisMat()
2507 
2508    The PETSc implementation also supports multilevel BDDC [3]. Coarse grids are partitioned using a MatPartitioning object.
2509 
2510    Adaptive selection of primal constraints [4] is supported for SPD systems with high-contrast in the coefficients if MUMPS or MKL_PARDISO are present. Future versions of the code will also consider using PASTIX.
2511 
2512    An experimental interface to the FETI-DP method is available. FETI-DP operators could be created using PCBDDCCreateFETIDPOperators(). A stand-alone class for the FETI-DP method will be provided in the next releases.
2513    Deluxe scaling is not supported yet for FETI-DP.
2514 
2515    Options Database Keys (some of them, run with -h for a complete list):
2516 
2517 .    -pc_bddc_use_vertices <true> - use or not vertices in primal space
2518 .    -pc_bddc_use_edges <true> - use or not edges in primal space
2519 .    -pc_bddc_use_faces <false> - use or not faces in primal space
2520 .    -pc_bddc_symmetric <true> - symmetric computation of primal basis functions. Specify false for unsymmetric problems
2521 .    -pc_bddc_use_change_of_basis <false> - use change of basis approach (on edges only)
2522 .    -pc_bddc_use_change_on_faces <false> - use change of basis approach on faces if change of basis has been requested
2523 .    -pc_bddc_switch_static <false> - switches from M_2 (default) to M_3 operator (see reference article [1])
2524 .    -pc_bddc_levels <0> - maximum number of levels for multilevel
2525 .    -pc_bddc_coarsening_ratio <8> - number of subdomains which will be aggregated together at the coarser level (e.g. H/h ratio at the coarser level, significative only in the multilevel case)
2526 .    -pc_bddc_coarse_redistribute <0> - size of a subset of processors where the coarse problem will be remapped (the value is ignored if not at the coarsest level)
2527 .    -pc_bddc_use_deluxe_scaling <false> - use deluxe scaling
2528 .    -pc_bddc_schur_layers <-1> - select the economic version of deluxe scaling by specifying the number of layers (-1 corresponds to the original deluxe scaling)
2529 .    -pc_bddc_adaptive_threshold <0.0> - when a value greater than one is specified, adaptive selection of constraints is performed on edges and faces (requires deluxe scaling and MUMPS or MKL_PARDISO installed)
2530 -    -pc_bddc_check_level <0> - set verbosity level of debugging output
2531 
2532    Options for Dirichlet, Neumann or coarse solver can be set with
2533 .vb
2534       -pc_bddc_dirichlet_
2535       -pc_bddc_neumann_
2536       -pc_bddc_coarse_
2537 .ve
2538    e.g -pc_bddc_dirichlet_ksp_type richardson -pc_bddc_dirichlet_pc_type gamg. PCBDDC uses by default KPSPREONLY and PCLU.
2539 
2540    When using a multilevel approach, solvers' options at the N-th level (N > 1) can be specified as
2541 .vb
2542       -pc_bddc_dirichlet_lN_
2543       -pc_bddc_neumann_lN_
2544       -pc_bddc_coarse_lN_
2545 .ve
2546    Note that level number ranges from the finest (0) to the coarsest (N).
2547    In order to specify options for the BDDC operators at the coarser levels (and not for the solvers), prepend -pc_bddc_coarse_ or -pc_bddc_coarse_l to the option, e.g.
2548 .vb
2549      -pc_bddc_coarse_pc_bddc_adaptive_threshold 5 -pc_bddc_coarse_l1_pc_bddc_redistribute 3
2550 .ve
2551    will use a threshold of 5 for constraints' selection at the first coarse level and will redistribute the coarse problem of the first coarse level on 3 processors
2552 
2553    Level: intermediate
2554 
2555    Developer notes:
2556 
2557    Contributed by Stefano Zampini
2558 
2559 .seealso:  PCCreate(), PCSetType(), PCType (for list of available types), PC,  MATIS
2560 M*/
2561 
2562 PETSC_EXTERN PetscErrorCode PCCreate_BDDC(PC pc)
2563 {
2564   PetscErrorCode      ierr;
2565   PC_BDDC             *pcbddc;
2566 
2567   PetscFunctionBegin;
2568   ierr     = PetscNewLog(pc,&pcbddc);CHKERRQ(ierr);
2569   pc->data = (void*)pcbddc;
2570 
2571   /* create PCIS data structure */
2572   ierr = PCISCreate(pc);CHKERRQ(ierr);
2573 
2574   /* create local graph structure */
2575   ierr = PCBDDCGraphCreate(&pcbddc->mat_graph);CHKERRQ(ierr);
2576 
2577   /* BDDC nonzero defaults */
2578   pcbddc->use_local_adj             = PETSC_TRUE;
2579   pcbddc->use_vertices              = PETSC_TRUE;
2580   pcbddc->use_edges                 = PETSC_TRUE;
2581   pcbddc->symmetric_primal          = PETSC_TRUE;
2582   pcbddc->vertex_size               = 1;
2583   pcbddc->recompute_topography      = PETSC_TRUE;
2584   pcbddc->coarse_size               = -1;
2585   pcbddc->use_exact_dirichlet_trick = PETSC_TRUE;
2586   pcbddc->coarsening_ratio          = 8;
2587   pcbddc->coarse_eqs_per_proc       = 1;
2588   pcbddc->benign_compute_correction = PETSC_TRUE;
2589   pcbddc->nedfield                  = -1;
2590   pcbddc->nedglobal                 = PETSC_TRUE;
2591   pcbddc->graphmaxcount             = PETSC_MAX_INT;
2592   pcbddc->sub_schurs_layers         = -1;
2593 
2594   /* function pointers */
2595   pc->ops->apply               = PCApply_BDDC;
2596   pc->ops->applytranspose      = PCApplyTranspose_BDDC;
2597   pc->ops->setup               = PCSetUp_BDDC;
2598   pc->ops->destroy             = PCDestroy_BDDC;
2599   pc->ops->setfromoptions      = PCSetFromOptions_BDDC;
2600   pc->ops->view                = PCView_BDDC;
2601   pc->ops->applyrichardson     = 0;
2602   pc->ops->applysymmetricleft  = 0;
2603   pc->ops->applysymmetricright = 0;
2604   pc->ops->presolve            = PCPreSolve_BDDC;
2605   pc->ops->postsolve           = PCPostSolve_BDDC;
2606   pc->ops->reset               = PCReset_BDDC;
2607 
2608   /* composing function */
2609   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDiscreteGradient_C",PCBDDCSetDiscreteGradient_BDDC);CHKERRQ(ierr);
2610   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDivergenceMat_C",PCBDDCSetDivergenceMat_BDDC);CHKERRQ(ierr);
2611   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetChangeOfBasisMat_C",PCBDDCSetChangeOfBasisMat_BDDC);CHKERRQ(ierr);
2612   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetPrimalVerticesLocalIS_C",PCBDDCSetPrimalVerticesLocalIS_BDDC);CHKERRQ(ierr);
2613   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetPrimalVerticesIS_C",PCBDDCSetPrimalVerticesIS_BDDC);CHKERRQ(ierr);
2614   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetCoarseningRatio_C",PCBDDCSetCoarseningRatio_BDDC);CHKERRQ(ierr);
2615   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetLevel_C",PCBDDCSetLevel_BDDC);CHKERRQ(ierr);
2616   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetUseExactDirichlet_C",PCBDDCSetUseExactDirichlet_BDDC);CHKERRQ(ierr);
2617   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetLevels_C",PCBDDCSetLevels_BDDC);CHKERRQ(ierr);
2618   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDirichletBoundaries_C",PCBDDCSetDirichletBoundaries_BDDC);CHKERRQ(ierr);
2619   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDirichletBoundariesLocal_C",PCBDDCSetDirichletBoundariesLocal_BDDC);CHKERRQ(ierr);
2620   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetNeumannBoundaries_C",PCBDDCSetNeumannBoundaries_BDDC);CHKERRQ(ierr);
2621   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetNeumannBoundariesLocal_C",PCBDDCSetNeumannBoundariesLocal_BDDC);CHKERRQ(ierr);
2622   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCGetDirichletBoundaries_C",PCBDDCGetDirichletBoundaries_BDDC);CHKERRQ(ierr);
2623   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCGetDirichletBoundariesLocal_C",PCBDDCGetDirichletBoundariesLocal_BDDC);CHKERRQ(ierr);
2624   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCGetNeumannBoundaries_C",PCBDDCGetNeumannBoundaries_BDDC);CHKERRQ(ierr);
2625   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCGetNeumannBoundariesLocal_C",PCBDDCGetNeumannBoundariesLocal_BDDC);CHKERRQ(ierr);
2626   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDofsSplitting_C",PCBDDCSetDofsSplitting_BDDC);CHKERRQ(ierr);
2627   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetDofsSplittingLocal_C",PCBDDCSetDofsSplittingLocal_BDDC);CHKERRQ(ierr);
2628   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCSetLocalAdjacencyGraph_C",PCBDDCSetLocalAdjacencyGraph_BDDC);CHKERRQ(ierr);
2629   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCCreateFETIDPOperators_C",PCBDDCCreateFETIDPOperators_BDDC);CHKERRQ(ierr);
2630   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCMatFETIDPGetRHS_C",PCBDDCMatFETIDPGetRHS_BDDC);CHKERRQ(ierr);
2631   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCBDDCMatFETIDPGetSolution_C",PCBDDCMatFETIDPGetSolution_BDDC);CHKERRQ(ierr);
2632   ierr = PetscObjectComposeFunction((PetscObject)pc,"PCPreSolveChangeRHS_C",PCPreSolveChangeRHS_BDDC);CHKERRQ(ierr);
2633   PetscFunctionReturn(0);
2634 }
2635 
2636