xref: /petsc/src/dm/impls/da/da1.c (revision af0996ce37bc06907c37d8d91773840993d61e62) !
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 <petsc/private/dmdaimpl.h>     /*I  "petscdmda.h"   I*/
8 
9 #include <petscdraw.h>
10 #undef __FUNCT__
11 #define __FUNCT__ "DMView_DA_1d"
12 PetscErrorCode DMView_DA_1d(DM da,PetscViewer viewer)
13 {
14   PetscErrorCode ierr;
15   PetscMPIInt    rank;
16   PetscBool      iascii,isdraw,isbinary;
17   DM_DA          *dd = (DM_DA*)da->data;
18 #if defined(PETSC_HAVE_MATLAB_ENGINE)
19   PetscBool ismatlab;
20 #endif
21 
22   PetscFunctionBegin;
23   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)da),&rank);CHKERRQ(ierr);
24 
25   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
26   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
27   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
28 #if defined(PETSC_HAVE_MATLAB_ENGINE)
29   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERMATLAB,&ismatlab);CHKERRQ(ierr);
30 #endif
31   if (iascii) {
32     PetscViewerFormat format;
33 
34     ierr = PetscViewerGetFormat(viewer, &format);CHKERRQ(ierr);
35     if (format != PETSC_VIEWER_ASCII_VTK && format != PETSC_VIEWER_ASCII_VTK_CELL) {
36       DMDALocalInfo info;
37       ierr = DMDAGetLocalInfo(da,&info);CHKERRQ(ierr);
38       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_TRUE);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       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_FALSE);CHKERRQ(ierr);
43     } else {
44       ierr = DMView_DA_VTK(da, viewer);CHKERRQ(ierr);
45     }
46   } else if (isdraw) {
47     PetscDraw draw;
48     double    ymin = -1,ymax = 1,xmin = -1,xmax = dd->M,x;
49     PetscInt  base;
50     char      node[10];
51     PetscBool isnull;
52 
53     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
54     ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr); if (isnull) PetscFunctionReturn(0);
55 
56     ierr = PetscDrawSetCoordinates(draw,xmin,ymin,xmax,ymax);CHKERRQ(ierr);
57     ierr = PetscDrawSynchronizedClear(draw);CHKERRQ(ierr);
58 
59     /* first processor draws all node lines */
60     if (!rank) {
61       PetscInt xmin_tmp;
62       ymin = 0.0; ymax = 0.3;
63 
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   }
99   PetscFunctionReturn(0);
100 }
101 
102 
103 #undef __FUNCT__
104 #define __FUNCT__ "DMSetUp_DA_1D"
105 PetscErrorCode  DMSetUp_DA_1D(DM da)
106 {
107   DM_DA            *dd   = (DM_DA*)da->data;
108   const PetscInt   M     = dd->M;
109   const PetscInt   dof   = dd->w;
110   const PetscInt   s     = dd->s;
111   const PetscInt   sDist = s;  /* stencil distance in points */
112   const PetscInt   *lx   = dd->lx;
113   DMBoundaryType   bx    = dd->bx;
114   MPI_Comm         comm;
115   Vec              local, global;
116   VecScatter       gtol;
117   IS               to, from;
118   PetscBool        flg1 = PETSC_FALSE, flg2 = PETSC_FALSE;
119   PetscMPIInt      rank, size;
120   PetscInt         i,*idx,nn,left,xs,xe,x,Xs,Xe,start,m,IXs,IXe;
121   PetscErrorCode   ierr;
122 
123   PetscFunctionBegin;
124   ierr = PetscObjectGetComm((PetscObject) da, &comm);CHKERRQ(ierr);
125   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
126   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
127 
128   dd->p = 1;
129   dd->n = 1;
130   dd->m = size;
131   m     = dd->m;
132 
133   if (s > 0) {
134     /* if not communicating data then should be ok to have nothing on some processes */
135     if (M < m) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"More processes than data points! %D %D",m,M);
136     if ((M-1) < s && size > 1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Array is too small for stencil! %D %D",M-1,s);
137   }
138 
139   /*
140      Determine locally owned region
141      xs is the first local node number, x is the number of local nodes
142   */
143   if (!lx) {
144     ierr = PetscMalloc1(m, &dd->lx);CHKERRQ(ierr);
145     ierr = PetscOptionsGetBool(NULL,"-da_partition_blockcomm",&flg1,NULL);CHKERRQ(ierr);
146     ierr = PetscOptionsGetBool(NULL,"-da_partition_nodes_at_end",&flg2,NULL);CHKERRQ(ierr);
147     if (flg1) {      /* Block Comm type Distribution */
148       xs = rank*M/m;
149       x  = (rank + 1)*M/m - xs;
150     } else if (flg2) { /* The odd nodes are evenly distributed across last nodes */
151       x = (M + rank)/m;
152       if (M/m == x) xs = rank*x;
153       else          xs = rank*(x-1) + (M+rank)%(x*m);
154     } else { /* The odd nodes are evenly distributed across the first k nodes */
155       /* Regular PETSc Distribution */
156       x = M/m + ((M % m) > rank);
157       if (rank >= (M % m)) xs = (rank * (PetscInt)(M/m) + M % m);
158       else                 xs = rank * (PetscInt)(M/m) + rank;
159     }
160     ierr = MPI_Allgather(&xs,1,MPIU_INT,dd->lx,1,MPIU_INT,comm);CHKERRQ(ierr);
161     for (i=0; i<m-1; i++) dd->lx[i] = dd->lx[i+1] - dd->lx[i];
162     dd->lx[m-1] = M - dd->lx[m-1];
163   } else {
164     x  = lx[rank];
165     xs = 0;
166     for (i=0; i<rank; i++) xs += lx[i];
167     /* verify that data user provided is consistent */
168     left = xs;
169     for (i=rank; i<size; i++) left += lx[i];
170     if (left != M) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Sum of lx across processors not equal to M %D %D",left,M);
171   }
172 
173   /*
174    check if the scatter requires more than one process neighbor or wraps around
175    the domain more than once
176   */
177   if ((x < s) & ((M > 1) | (bx == DM_BOUNDARY_PERIODIC))) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Local x-width of domain x %D is smaller than stencil width s %D",x,s);
178 
179   xe  = xs + x;
180 
181   /* determine ghost region (Xs) and region scattered into (IXs)  */
182   if (xs-sDist > 0) {
183     Xs  = xs - sDist;
184     IXs = xs - sDist;
185   } else {
186     if (bx) Xs = xs - sDist;
187     else Xs = 0;
188     IXs = 0;
189   }
190   if (xe+sDist <= M) {
191     Xe  = xe + sDist;
192     IXe = xe + sDist;
193   } else {
194     if (bx) Xe = xe + sDist;
195     else Xe = M;
196     IXe = M;
197   }
198 
199   if (bx == DM_BOUNDARY_PERIODIC || bx == DM_BOUNDARY_MIRROR) {
200     Xs  = xs - sDist;
201     Xe  = xe + sDist;
202     IXs = xs - sDist;
203     IXe = xe + sDist;
204   }
205 
206   /* allocate the base parallel and sequential vectors */
207   dd->Nlocal = dof*x;
208   ierr       = VecCreateMPIWithArray(comm,dof,dd->Nlocal,PETSC_DECIDE,NULL,&global);CHKERRQ(ierr);
209   dd->nlocal = dof*(Xe-Xs);
210   ierr       = VecCreateSeqWithArray(PETSC_COMM_SELF,dof,dd->nlocal,NULL,&local);CHKERRQ(ierr);
211 
212   ierr = VecGetOwnershipRange(global,&start,NULL);CHKERRQ(ierr);
213 
214   /* Create Global to Local Vector Scatter Context */
215   /* global to local must retrieve ghost points */
216   ierr = ISCreateStride(comm,dof*(IXe-IXs),dof*(IXs-Xs),1,&to);CHKERRQ(ierr);
217 
218   ierr = PetscMalloc1(x+2*sDist,&idx);CHKERRQ(ierr);
219   ierr = PetscLogObjectMemory((PetscObject)da,(x+2*(sDist))*sizeof(PetscInt));CHKERRQ(ierr);
220 
221   for (i=0; i<IXs-Xs; i++) idx[i] = -1; /* prepend with -1s if needed for ghosted case*/
222 
223   nn = IXs-Xs;
224   if (bx == DM_BOUNDARY_PERIODIC) { /* Handle all cases with periodic first */
225     for (i=0; i<sDist; i++) {  /* Left ghost points */
226       if ((xs-sDist+i)>=0) idx[nn++] = xs-sDist+i;
227       else                 idx[nn++] = M+(xs-sDist+i);
228     }
229 
230     for (i=0; i<x; i++) idx [nn++] = xs + i;  /* Non-ghost points */
231 
232     for (i=0; i<sDist; i++) { /* Right ghost points */
233       if ((xe+i)<M) idx [nn++] =  xe+i;
234       else          idx [nn++] = (xe+i) - M;
235     }
236   } else if (bx == DM_BOUNDARY_MIRROR) { /* Handle all cases with periodic first */
237     for (i=0; i<(sDist); i++) {  /* Left ghost points */
238       if ((xs-sDist+i)>=0) idx[nn++] = xs-sDist+i;
239       else                 idx[nn++] = sDist - i;
240     }
241 
242     for (i=0; i<x; i++) idx [nn++] = xs + i;  /* Non-ghost points */
243 
244     for (i=0; i<(sDist); i++) { /* Right ghost points */
245       if ((xe+i)<M) idx[nn++] =  xe+i;
246       else          idx[nn++] = M - (i + 1);
247     }
248   } else {      /* Now do all cases with no periodicity */
249     if (0 <= xs-sDist) {
250       for (i=0; i<sDist; i++) idx[nn++] = xs - sDist + i;
251     } else {
252       for (i=0; i<xs; i++) idx[nn++] = i;
253     }
254 
255     for (i=0; i<x; i++) idx [nn++] = xs + i;
256 
257     if ((xe+sDist)<=M) {
258       for (i=0; i<sDist; i++) idx[nn++]=xe+i;
259     } else {
260       for (i=xe; i<M; i++) idx[nn++]=i;
261     }
262   }
263 
264   ierr = ISCreateBlock(comm,dof,nn-IXs+Xs,&idx[IXs-Xs],PETSC_USE_POINTER,&from);CHKERRQ(ierr);
265   ierr = VecScatterCreate(global,from,local,to,&gtol);CHKERRQ(ierr);
266   ierr = PetscLogObjectParent((PetscObject)da,(PetscObject)gtol);CHKERRQ(ierr);
267   ierr = ISDestroy(&to);CHKERRQ(ierr);
268   ierr = ISDestroy(&from);CHKERRQ(ierr);
269   ierr = VecDestroy(&local);CHKERRQ(ierr);
270   ierr = VecDestroy(&global);CHKERRQ(ierr);
271 
272   dd->xs = dof*xs; dd->xe = dof*xe; dd->ys = 0; dd->ye = 1; dd->zs = 0; dd->ze = 1;
273   dd->Xs = dof*Xs; dd->Xe = dof*Xe; dd->Ys = 0; dd->Ye = 1; dd->Zs = 0; dd->Ze = 1;
274 
275   dd->gtol      = gtol;
276   dd->base      = dof*xs;
277   da->ops->view = DMView_DA_1d;
278 
279   /*
280      Set the local to global ordering in the global vector, this allows use
281      of VecSetValuesLocal().
282   */
283   for (i=0; i<Xe-IXe; i++) idx[nn++] = -1; /* pad with -1s if needed for ghosted case*/
284 
285   ierr = ISLocalToGlobalMappingCreate(comm,dof,nn,idx,PETSC_OWN_POINTER,&da->ltogmap);CHKERRQ(ierr);
286   ierr = PetscLogObjectParent((PetscObject)da,(PetscObject)da->ltogmap);CHKERRQ(ierr);
287 
288   PetscFunctionReturn(0);
289 }
290 
291 
292 #undef __FUNCT__
293 #define __FUNCT__ "DMDACreate1d"
294 /*@C
295    DMDACreate1d - Creates an object that will manage the communication of  one-dimensional
296    regular array data that is distributed across some processors.
297 
298    Collective on MPI_Comm
299 
300    Input Parameters:
301 +  comm - MPI communicator
302 .  bx - type of ghost cells at the boundary the array should have, if any. Use
303           DM_BOUNDARY_NONE, DM_BOUNDARY_GHOSTED, or DM_BOUNDARY_PERIODIC.
304 .  M - global dimension of the array (use -M to indicate that it may be set to a different value
305             from the command line with -da_grid_x <M>)
306 .  dof - number of degrees of freedom per node
307 .  s - stencil width
308 -  lx - array containing number of nodes in the X direction on each processor,
309         or NULL. If non-null, must be of length as the number of processes in the MPI_Comm.
310 
311    Output Parameter:
312 .  da - the resulting distributed array object
313 
314    Options Database Key:
315 +  -dm_view - Calls DMView() at the conclusion of DMDACreate1d()
316 .  -da_grid_x <nx> - number of grid points in x direction; can set if M < 0
317 .  -da_refine_x <rx> - refinement factor
318 -  -da_refine <n> - refine the DMDA n times before creating it, if M < 0
319 
320    Level: beginner
321 
322    Notes:
323    The array data itself is NOT stored in the DMDA, it is stored in Vec objects;
324    The appropriate vector objects can be obtained with calls to DMCreateGlobalVector()
325    and DMCreateLocalVector() and calls to VecDuplicate() if more are needed.
326 
327 .keywords: distributed array, create, one-dimensional
328 
329 .seealso: DMDestroy(), DMView(), DMDACreate2d(), DMDACreate3d(), DMGlobalToLocalBegin(), DMDASetRefinementFactor(),
330           DMGlobalToLocalEnd(), DMLocalToGlobalBegin(), DMLocalToLocalBegin(), DMLocalToLocalEnd(), DMDAGetRefinementFactor(),
331           DMDAGetInfo(), DMCreateGlobalVector(), DMCreateLocalVector(), DMDACreateNaturalVector(), DMLoad(), DMDAGetOwnershipRanges()
332 
333 @*/
334 PetscErrorCode  DMDACreate1d(MPI_Comm comm, DMBoundaryType bx, PetscInt M, PetscInt dof, PetscInt s, const PetscInt lx[], DM *da)
335 {
336   PetscErrorCode ierr;
337   PetscMPIInt    size;
338 
339   PetscFunctionBegin;
340   ierr = DMDACreate(comm, da);CHKERRQ(ierr);
341   ierr = DMSetDimension(*da, 1);CHKERRQ(ierr);
342   ierr = DMDASetSizes(*da, M, 1, 1);CHKERRQ(ierr);
343   ierr = MPI_Comm_size(comm, &size);CHKERRQ(ierr);
344   ierr = DMDASetNumProcs(*da, size, PETSC_DECIDE, PETSC_DECIDE);CHKERRQ(ierr);
345   ierr = DMDASetBoundaryType(*da, bx, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE);CHKERRQ(ierr);
346   ierr = DMDASetDof(*da, dof);CHKERRQ(ierr);
347   ierr = DMDASetStencilWidth(*da, s);CHKERRQ(ierr);
348   ierr = DMDASetOwnershipRanges(*da, lx, NULL, NULL);CHKERRQ(ierr);
349   /* This violates the behavior for other classes, but right now users expect negative dimensions to be handled this way */
350   ierr = DMSetFromOptions(*da);CHKERRQ(ierr);
351   ierr = DMSetUp(*da);CHKERRQ(ierr);
352   PetscFunctionReturn(0);
353 }
354