xref: /petsc/src/dm/impls/da/da1.c (revision 7d0a6c19129e7069c8a40e210b34ed62989173db)
1 
2 /*
3    Code for manipulating distributed regular 1d arrays in parallel.
4    This file was created by Peter Mell   6/30/95
5 */
6 
7 #include "private/daimpl.h"     /*I  "petscdm.h"   I*/
8 
9 const char *DMDABoundaryTypes[] = {"BOUNDARY_NONE","BOUNDARY_GHOSTED","BOUNDARY_PERIODIC","DMDA_",0};
10 
11 #undef __FUNCT__
12 #define __FUNCT__ "DMView_DA_1d"
13 PetscErrorCode DMView_DA_1d(DM da,PetscViewer viewer)
14 {
15   PetscErrorCode ierr;
16   PetscMPIInt    rank;
17   PetscBool      iascii,isdraw,isbinary;
18   DM_DA          *dd = (DM_DA*)da->data;
19 #if defined(PETSC_HAVE_MATLAB_ENGINE)
20   PetscBool      ismatlab;
21 #endif
22 
23   PetscFunctionBegin;
24   ierr = MPI_Comm_rank(((PetscObject)da)->comm,&rank);CHKERRQ(ierr);
25 
26   ierr = PetscTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
27   ierr = PetscTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
28   ierr = PetscTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
29 #if defined(PETSC_HAVE_MATLAB_ENGINE)
30   ierr = PetscTypeCompare((PetscObject)viewer,PETSCVIEWERMATLAB,&ismatlab);CHKERRQ(ierr);
31 #endif
32   if (iascii) {
33     PetscViewerFormat format;
34 
35     ierr = PetscViewerGetFormat(viewer, &format);CHKERRQ(ierr);
36     if (format != PETSC_VIEWER_ASCII_VTK && format != PETSC_VIEWER_ASCII_VTK_CELL) {
37       DMDALocalInfo info;
38       ierr = DMDAGetLocalInfo(da,&info);CHKERRQ(ierr);
39       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"Processor [%d] M %D m %D w %D s %D\n",rank,dd->M,dd->m,dd->w,dd->s);CHKERRQ(ierr);
40       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"X range of indices: %D %D\n",info.xs,info.xs+info.xm);CHKERRQ(ierr);
41       ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
42     } else {
43       ierr = DMView_DA_VTK(da, viewer);CHKERRQ(ierr);
44     }
45   } else if (isdraw) {
46     PetscDraw  draw;
47     double     ymin = -1,ymax = 1,xmin = -1,xmax = dd->M,x;
48     PetscInt   base;
49     char       node[10];
50     PetscBool  isnull;
51 
52     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
53     ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr); if (isnull) PetscFunctionReturn(0);
54 
55     ierr = PetscDrawSetCoordinates(draw,xmin,ymin,xmax,ymax);CHKERRQ(ierr);
56     ierr = PetscDrawSynchronizedClear(draw);CHKERRQ(ierr);
57 
58     /* first processor draws all node lines */
59     if (!rank) {
60       PetscInt xmin_tmp;
61       ymin = 0.0; ymax = 0.3;
62 
63       /* ADIC doesn't like doubles in a for loop */
64       for (xmin_tmp =0; xmin_tmp < dd->M; xmin_tmp++) {
65          ierr = PetscDrawLine(draw,(double)xmin_tmp,ymin,(double)xmin_tmp,ymax,PETSC_DRAW_BLACK);CHKERRQ(ierr);
66       }
67 
68       xmin = 0.0; xmax = dd->M - 1;
69       ierr = PetscDrawLine(draw,xmin,ymin,xmax,ymin,PETSC_DRAW_BLACK);CHKERRQ(ierr);
70       ierr = PetscDrawLine(draw,xmin,ymax,xmax,ymax,PETSC_DRAW_BLACK);CHKERRQ(ierr);
71     }
72 
73     ierr = PetscDrawSynchronizedFlush(draw);CHKERRQ(ierr);
74     ierr = PetscDrawPause(draw);CHKERRQ(ierr);
75 
76     /* draw my box */
77     ymin = 0; ymax = 0.3; xmin = dd->xs / dd->w; xmax = (dd->xe / dd->w)  - 1;
78     ierr = PetscDrawLine(draw,xmin,ymin,xmax,ymin,PETSC_DRAW_RED);CHKERRQ(ierr);
79     ierr = PetscDrawLine(draw,xmin,ymin,xmin,ymax,PETSC_DRAW_RED);CHKERRQ(ierr);
80     ierr = PetscDrawLine(draw,xmin,ymax,xmax,ymax,PETSC_DRAW_RED);CHKERRQ(ierr);
81     ierr = PetscDrawLine(draw,xmax,ymin,xmax,ymax,PETSC_DRAW_RED);CHKERRQ(ierr);
82 
83     /* Put in index numbers */
84     base = dd->base / dd->w;
85     for (x=xmin; x<=xmax; x++) {
86       sprintf(node,"%d",(int)base++);
87       ierr = PetscDrawString(draw,x,ymin,PETSC_DRAW_RED,node);CHKERRQ(ierr);
88     }
89 
90     ierr = PetscDrawSynchronizedFlush(draw);CHKERRQ(ierr);
91     ierr = PetscDrawPause(draw);CHKERRQ(ierr);
92   } else if (isbinary){
93     ierr = DMView_DA_Binary(da,viewer);CHKERRQ(ierr);
94 #if defined(PETSC_HAVE_MATLAB_ENGINE)
95   } else if (ismatlab) {
96     ierr = DMView_DA_Matlab(da,viewer);CHKERRQ(ierr);
97 #endif
98   } else SETERRQ1(((PetscObject)da)->comm,PETSC_ERR_SUP,"Viewer type %s not supported for DMDA 1d",((PetscObject)viewer)->type_name);
99   PetscFunctionReturn(0);
100 }
101 
102 #undef __FUNCT__
103 #define __FUNCT__ "DMView_DA_Private"
104 /*
105     Processes command line options to determine if/how a DMDA
106   is to be viewed. Called by DMDACreateXX()
107 */
108 PetscErrorCode DMView_DA_Private(DM da)
109 {
110   PetscErrorCode ierr;
111   PetscBool      flg1 = PETSC_FALSE;
112   PetscViewer    view;
113 
114   PetscFunctionBegin;
115   ierr = PetscOptionsBegin(((PetscObject)da)->comm,((PetscObject)da)->prefix,"DMDA viewing options","DMDA");CHKERRQ(ierr);
116     ierr = PetscOptionsBool("-da_view","Print information about the DMDA's distribution","DMView",PETSC_FALSE,&flg1,PETSC_NULL);CHKERRQ(ierr);
117     if (flg1) {
118       ierr = PetscViewerASCIIGetStdout(((PetscObject)da)->comm,&view);CHKERRQ(ierr);
119       ierr = DMView(da,view);CHKERRQ(ierr);
120     }
121     flg1 = PETSC_FALSE;
122     ierr = PetscOptionsBool("-da_view_draw","Draw how the DMDA is distributed","DMView",PETSC_FALSE,&flg1,PETSC_NULL);CHKERRQ(ierr);
123     if (flg1) {ierr = DMView(da,PETSC_VIEWER_DRAW_(((PetscObject)da)->comm));CHKERRQ(ierr);}
124   ierr = PetscOptionsEnd();CHKERRQ(ierr);
125   PetscFunctionReturn(0);
126 }
127 
128 #undef __FUNCT__
129 #define __FUNCT__ "DMSetUp_DA_1D"
130 PetscErrorCode  DMSetUp_DA_1D(DM da)
131 {
132   DM_DA                  *dd = (DM_DA*)da->data;
133   const PetscInt         M     = dd->M;
134   const PetscInt         dof   = dd->w;
135   const PetscInt         s     = dd->s;
136   const PetscInt         sDist = s*dof;  /* absolute stencil distance */
137   const PetscInt         *lx    = dd->lx;
138   const DMDABoundaryType bx  = dd->bx;
139   MPI_Comm               comm;
140   Vec                    local, global;
141   VecScatter             ltog, gtol;
142   IS                     to, from;
143   PetscBool              flg1 = PETSC_FALSE, flg2 = PETSC_FALSE;
144   PetscMPIInt            rank, size;
145   PetscInt               i,*idx,nn,left,xs,xe,x,Xs,Xe,start,end,m,IXs,IXe;
146   PetscErrorCode         ierr;
147 
148   PetscFunctionBegin;
149   if (dof < 1) SETERRQ1(((PetscObject)da)->comm,PETSC_ERR_ARG_OUTOFRANGE,"Must have 1 or more degrees of freedom per node: %D",dof);
150   if (s < 0) SETERRQ1(((PetscObject)da)->comm,PETSC_ERR_ARG_OUTOFRANGE,"Stencil width cannot be negative: %D",s);
151 
152   dd->dim = 1;
153   ierr = PetscMalloc(dof*sizeof(char*),&dd->fieldname);CHKERRQ(ierr);
154   ierr = PetscMemzero(dd->fieldname,dof*sizeof(char*));CHKERRQ(ierr);
155   ierr = PetscObjectGetComm((PetscObject) da, &comm);CHKERRQ(ierr);
156   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
157   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
158 
159   dd->m = size;
160   m     = dd->m;
161 
162   if (s > 0) {
163     /* if not communicating data then should be ok to have nothing on some processes */
164     if (M < m)     SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"More processes than data points! %D %D",m,M);
165     if ((M-1) < s) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Array is too small for stencil! %D %D",M-1,s);
166   }
167 
168   /*
169      Determine locally owned region
170      xs is the first local node number, x is the number of local nodes
171   */
172   if (!lx) {
173     ierr = PetscOptionsGetBool(PETSC_NULL,"-da_partition_blockcomm",&flg1,PETSC_NULL);CHKERRQ(ierr);
174     ierr = PetscOptionsGetBool(PETSC_NULL,"-da_partition_nodes_at_end",&flg2,PETSC_NULL);CHKERRQ(ierr);
175     if (flg1) {      /* Block Comm type Distribution */
176       xs = rank*M/m;
177       x  = (rank + 1)*M/m - xs;
178     } else if (flg2) { /* The odd nodes are evenly distributed across last nodes */
179       x = (M + rank)/m;
180       if (M/m == x) { xs = rank*x; }
181       else          { xs = rank*(x-1) + (M+rank)%(x*m); }
182     } else { /* The odd nodes are evenly distributed across the first k nodes */
183       /* Regular PETSc Distribution */
184       x = M/m + ((M % m) > rank);
185       if (rank >= (M % m)) {xs = (rank * (PetscInt)(M/m) + M % m);}
186       else                 {xs = rank * (PetscInt)(M/m) + rank;}
187     }
188   } else {
189     x  = lx[rank];
190     xs = 0;
191     for (i=0; i<rank; i++) {
192       xs += lx[i];
193     }
194     /* verify that data user provided is consistent */
195     left = xs;
196     for (i=rank; i<size; i++) {
197       left += lx[i];
198     }
199     if (left != M) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Sum of lx across processors not equal to M %D %D",left,M);
200   }
201 
202   /* From now on x,xs,xe,Xs,Xe are the exact location in the array */
203   x  *= dof;
204   xs *= dof;
205   xe  = xs + x;
206 
207   /* determine ghost region */
208   if (bx) {
209     Xs = xs - sDist;
210     Xe = xe + sDist;
211   } else {
212     if ((xs-sDist) >= 0)     Xs = xs-sDist;  else Xs = 0;
213     if ((xe+sDist) <= M*dof) Xe = xe+sDist;  else Xe = M*dof;
214   }
215 
216   if (bx == DMDA_BOUNDARY_PERIODIC) {
217     IXs = xs - sDist;
218     IXe = xe + sDist;
219   } else {
220     if ((xs-sDist) >= 0)     IXs = xs-sDist;  else IXs = 0;
221     if ((xe+sDist) <= M*dof) IXe = xe+sDist;  else IXe = M*dof;
222   }
223 
224   /* allocate the base parallel and sequential vectors */
225   dd->Nlocal = x;
226   ierr = VecCreateMPIWithArray(comm,dd->Nlocal,PETSC_DECIDE,0,&global);CHKERRQ(ierr);
227   ierr = VecSetBlockSize(global,dof);CHKERRQ(ierr);
228   dd->nlocal = (Xe-Xs);
229   ierr = VecCreateSeqWithArray(PETSC_COMM_SELF,dd->nlocal,0,&local);CHKERRQ(ierr);
230   ierr = VecSetBlockSize(local,dof);CHKERRQ(ierr);
231 
232   /* Create Local to Global Vector Scatter Context */
233   /* local to global inserts non-ghost point region into global */
234   ierr = VecGetOwnershipRange(global,&start,&end);CHKERRQ(ierr);
235   ierr = ISCreateStride(comm,x,start,1,&to);CHKERRQ(ierr);
236   ierr = ISCreateStride(comm,x,xs-Xs,1,&from);CHKERRQ(ierr);
237   ierr = VecScatterCreate(local,from,global,to,&ltog);CHKERRQ(ierr);
238   ierr = PetscLogObjectParent(da,ltog);CHKERRQ(ierr);
239   ierr = ISDestroy(from);CHKERRQ(ierr);
240   ierr = ISDestroy(to);CHKERRQ(ierr);
241 
242   /* Create Global to Local Vector Scatter Context */
243   /* global to local must retrieve ghost points */
244   ierr = ISCreateStride(comm,(IXe-IXs),IXs-Xs,1,&to);CHKERRQ(ierr);
245 
246   ierr = PetscMalloc((x+2*sDist)*sizeof(PetscInt),&idx);CHKERRQ(ierr);
247   ierr = PetscLogObjectMemory(da,(x+2*sDist)*sizeof(PetscInt));CHKERRQ(ierr);
248 
249   for (i=0; i<IXs-Xs; i++) {idx[i] = -1; } /* prepend with -1s if needed for ghosted case*/
250 
251   nn = IXs-Xs;
252   if (bx == DMDA_BOUNDARY_PERIODIC) { /* Handle all cases with wrap first */
253     for (i=0; i<sDist; i++) {  /* Left ghost points */
254       if ((xs-sDist+i)>=0) { idx[nn++] = xs-sDist+i;}
255       else                 { idx[nn++] = M*dof+(xs-sDist+i);}
256     }
257 
258     for (i=0; i<x; i++) { idx [nn++] = xs + i;}  /* Non-ghost points */
259 
260     for (i=0; i<sDist; i++) { /* Right ghost points */
261       if ((xe+i)<M*dof) { idx [nn++] =  xe+i; }
262       else              { idx [nn++] = (xe+i) - M*dof;}
263     }
264   } else {      /* Now do all cases with no wrapping */
265     if (sDist <= xs) {for (i=0; i<sDist; i++) {idx[nn++] = xs - sDist + i;}}
266     else             {for (i=0; i<xs;    i++) {idx[nn++] = i;}}
267 
268     for (i=0; i<x; i++) { idx [nn++] = xs + i;}
269 
270     if ((xe+sDist)<=M*dof) {for (i=0;  i<sDist;   i++) {idx[nn++]=xe+i;}}
271     else                   {for (i=xe; i<(M*dof); i++) {idx[nn++]=i;}}
272   }
273 
274   ierr = ISCreateGeneral(comm,nn-IXs+Xs,&idx[IXs-Xs],PETSC_COPY_VALUES,&from);CHKERRQ(ierr);
275   ierr = VecScatterCreate(global,from,local,to,&gtol);CHKERRQ(ierr);
276   ierr = PetscLogObjectParent(da,to);CHKERRQ(ierr);
277   ierr = PetscLogObjectParent(da,from);CHKERRQ(ierr);
278   ierr = PetscLogObjectParent(da,gtol);CHKERRQ(ierr);
279   ierr = ISDestroy(to);CHKERRQ(ierr);
280   ierr = ISDestroy(from);CHKERRQ(ierr);
281   ierr = VecDestroy(local);CHKERRQ(ierr);
282   ierr = VecDestroy(global);CHKERRQ(ierr);
283 
284   dd->xs = xs; dd->xe = xe; dd->ys = 0; dd->ye = 1; dd->zs = 0; dd->ze = 1;
285   dd->Xs = Xs; dd->Xe = Xe; dd->Ys = 0; dd->Ye = 1; dd->Zs = 0; dd->Ze = 1;
286 
287   dd->gtol      = gtol;
288   dd->ltog      = ltog;
289   dd->base      = xs;
290   da->ops->view = DMView_DA_1d;
291 
292   /*
293      Set the local to global ordering in the global vector, this allows use
294      of VecSetValuesLocal().
295   */
296   for (i=0; i<Xe-IXe; i++) {idx[nn++] = -1; } /* pad with -1s if needed for ghosted case*/
297 
298   ierr = ISLocalToGlobalMappingCreate(comm,nn,idx,PETSC_COPY_VALUES,&da->ltogmap);CHKERRQ(ierr);
299   ierr = ISLocalToGlobalMappingBlock(da->ltogmap,dd->w,&da->ltogmapb);CHKERRQ(ierr);
300   ierr = PetscLogObjectParent(da,da->ltogmap);CHKERRQ(ierr);
301 
302   dd->idx = idx;
303   dd->Nl  = nn;
304 
305   PetscFunctionReturn(0);
306 }
307 
308 
309 #undef __FUNCT__
310 #define __FUNCT__ "DMDACreate1d"
311 /*@C
312    DMDACreate1d - Creates an object that will manage the communication of  one-dimensional
313    regular array data that is distributed across some processors.
314 
315    Collective on MPI_Comm
316 
317    Input Parameters:
318 +  comm - MPI communicator
319 .  bx - type of ghost cells at the boundary the array should have, if any. Use
320           DMDA_BOUNDARY_NONE, DMDA_BOUNDARY_GHOSTED, or DMDA_BOUNDARY_PERIODIC.
321 .  M - global dimension of the array (use -M to indicate that it may be set to a different value
322             from the command line with -da_grid_x <M>)
323 .  dof - number of degrees of freedom per node
324 .  s - stencil width
325 -  lx - array containing number of nodes in the X direction on each processor,
326         or PETSC_NULL. If non-null, must be of length as the number of processes in the MPI_Comm.
327 
328    Output Parameter:
329 .  da - the resulting distributed array object
330 
331    Options Database Key:
332 +  -da_view - Calls DMView() at the conclusion of DMDACreate1d()
333 .  -da_grid_x <nx> - number of grid points in x direction; can set if M < 0
334 -  -da_refine_x - refinement factor
335 
336    Level: beginner
337 
338    Notes:
339    The array data itself is NOT stored in the DMDA, it is stored in Vec objects;
340    The appropriate vector objects can be obtained with calls to DMCreateGlobalVector()
341    and DMCreateLocalVector() and calls to VecDuplicate() if more are needed.
342 
343 
344 .keywords: distributed array, create, one-dimensional
345 
346 .seealso: DMDestroy(), DMView(), DMDACreate2d(), DMDACreate3d(), DMGlobalToLocalBegin(), DMDASetRefinementFactor(),
347           DMGlobalToLocalEnd(), DMLocalToGlobalBegin(), DMDALocalToLocalBegin(), DMDALocalToLocalEnd(), DMDAGetRefinementFactor(),
348           DMDAGetInfo(), DMCreateGlobalVector(), DMCreateLocalVector(), DMDACreateNaturalVector(), DMDALoad(), DMDAGetOwnershipRanges()
349 
350 @*/
351 PetscErrorCode  DMDACreate1d(MPI_Comm comm, DMDABoundaryType bx, PetscInt M, PetscInt dof, PetscInt s, const PetscInt lx[], DM *da)
352 {
353   PetscErrorCode ierr;
354   PetscMPIInt    size;
355 
356   PetscFunctionBegin;
357   ierr = DMDACreate(comm, da);CHKERRQ(ierr);
358   ierr = DMDASetDim(*da, 1);CHKERRQ(ierr);
359   ierr = DMDASetSizes(*da, M, 1, 1);CHKERRQ(ierr);
360   ierr = MPI_Comm_size(comm, &size);CHKERRQ(ierr);
361   ierr = DMDASetNumProcs(*da, size, PETSC_DECIDE, PETSC_DECIDE);CHKERRQ(ierr);
362   ierr = DMDASetBoundaryType(*da, bx, DMDA_BOUNDARY_NONE, DMDA_BOUNDARY_NONE);CHKERRQ(ierr);
363   ierr = DMDASetDof(*da, dof);CHKERRQ(ierr);
364   ierr = DMDASetStencilWidth(*da, s);CHKERRQ(ierr);
365   ierr = DMDASetOwnershipRanges(*da, lx, PETSC_NULL, PETSC_NULL);CHKERRQ(ierr);
366   /* This violates the behavior for other classes, but right now users expect negative dimensions to be handled this way */
367   ierr = DMSetFromOptions(*da);CHKERRQ(ierr);
368   ierr = DMSetUp(*da);CHKERRQ(ierr);
369   ierr = DMView_DA_Private(*da);CHKERRQ(ierr);
370   PetscFunctionReturn(0);
371 }
372