xref: /petsc/src/dm/impls/da/gr2.c (revision 55e7fe800d976e85ed2b5cd8bfdef564daa37bd9)
1 
2 /*
3    Plots vectors obtained with DMDACreate2d()
4 */
5 
6 #include <petsc/private/dmdaimpl.h>      /*I  "petscdmda.h"   I*/
7 #include <petsc/private/glvisvecimpl.h>
8 #include <petscdraw.h>
9 #include <petscviewerhdf5.h>
10 
11 /*
12         The data that is passed into the graphics callback
13 */
14 typedef struct {
15   PetscMPIInt       rank;
16   PetscInt          m,n,dof,k;
17   PetscReal         xmin,xmax,ymin,ymax,min,max;
18   const PetscScalar *xy,*v;
19   PetscBool         showaxis,showgrid;
20   const char        *name0,*name1;
21 } ZoomCtx;
22 
23 /*
24        This does the drawing for one particular field
25     in one particular set of coordinates. It is a callback
26     called from PetscDrawZoom()
27 */
28 PetscErrorCode VecView_MPI_Draw_DA2d_Zoom(PetscDraw draw,void *ctx)
29 {
30   ZoomCtx           *zctx = (ZoomCtx*)ctx;
31   PetscErrorCode    ierr;
32   PetscInt          m,n,i,j,k,dof,id,c1,c2,c3,c4;
33   PetscReal         min,max,x1,x2,x3,x4,y_1,y2,y3,y4;
34   const PetscScalar *xy,*v;
35 
36   PetscFunctionBegin;
37   m    = zctx->m;
38   n    = zctx->n;
39   dof  = zctx->dof;
40   k    = zctx->k;
41   xy   = zctx->xy;
42   v    = zctx->v;
43   min  = zctx->min;
44   max  = zctx->max;
45 
46   /* PetscDraw the contour plot patch */
47   ierr = PetscDrawCollectiveBegin(draw);CHKERRQ(ierr);
48   for (j=0; j<n-1; j++) {
49     for (i=0; i<m-1; i++) {
50       id   = i+j*m;
51       x1   = PetscRealPart(xy[2*id]);
52       y_1  = PetscRealPart(xy[2*id+1]);
53       c1   = PetscDrawRealToColor(PetscRealPart(v[k+dof*id]),min,max);
54 
55       id   = i+j*m+1;
56       x2   = PetscRealPart(xy[2*id]);
57       y2   = PetscRealPart(xy[2*id+1]);
58       c2   = PetscDrawRealToColor(PetscRealPart(v[k+dof*id]),min,max);
59 
60       id   = i+j*m+1+m;
61       x3   = PetscRealPart(xy[2*id]);
62       y3   = PetscRealPart(xy[2*id+1]);
63       c3   = PetscDrawRealToColor(PetscRealPart(v[k+dof*id]),min,max);
64 
65       id   = i+j*m+m;
66       x4   = PetscRealPart(xy[2*id]);
67       y4   = PetscRealPart(xy[2*id+1]);
68       c4   = PetscDrawRealToColor(PetscRealPart(v[k+dof*id]),min,max);
69 
70       ierr = PetscDrawTriangle(draw,x1,y_1,x2,y2,x3,y3,c1,c2,c3);CHKERRQ(ierr);
71       ierr = PetscDrawTriangle(draw,x1,y_1,x3,y3,x4,y4,c1,c3,c4);CHKERRQ(ierr);
72       if (zctx->showgrid) {
73         ierr = PetscDrawLine(draw,x1,y_1,x2,y2,PETSC_DRAW_BLACK);CHKERRQ(ierr);
74         ierr = PetscDrawLine(draw,x2,y2,x3,y3,PETSC_DRAW_BLACK);CHKERRQ(ierr);
75         ierr = PetscDrawLine(draw,x3,y3,x4,y4,PETSC_DRAW_BLACK);CHKERRQ(ierr);
76         ierr = PetscDrawLine(draw,x4,y4,x1,y_1,PETSC_DRAW_BLACK);CHKERRQ(ierr);
77       }
78     }
79   }
80   if (zctx->showaxis && !zctx->rank) {
81     if (zctx->name0 || zctx->name1) {
82       PetscReal xl,yl,xr,yr,x,y;
83       ierr = PetscDrawGetCoordinates(draw,&xl,&yl,&xr,&yr);CHKERRQ(ierr);
84       x  = xl + .30*(xr - xl);
85       xl = xl + .01*(xr - xl);
86       y  = yr - .30*(yr - yl);
87       yl = yl + .01*(yr - yl);
88       if (zctx->name0) {ierr = PetscDrawString(draw,x,yl,PETSC_DRAW_BLACK,zctx->name0);CHKERRQ(ierr);}
89       if (zctx->name1) {ierr = PetscDrawStringVertical(draw,xl,y,PETSC_DRAW_BLACK,zctx->name1);CHKERRQ(ierr);}
90     }
91     /*
92        Ideally we would use the PetscDrawAxis object to manage displaying the coordinate limits
93        but that may require some refactoring.
94     */
95     {
96       double xmin = (double)zctx->xmin, ymin = (double)zctx->ymin;
97       double xmax = (double)zctx->xmax, ymax = (double)zctx->ymax;
98       char   value[16]; size_t len; PetscReal w;
99       ierr = PetscSNPrintf(value,16,"%0.2e",xmin);CHKERRQ(ierr);
100       ierr = PetscDrawString(draw,xmin,ymin - .05*(ymax - ymin),PETSC_DRAW_BLACK,value);CHKERRQ(ierr);
101       ierr = PetscSNPrintf(value,16,"%0.2e",xmax);CHKERRQ(ierr);
102       ierr = PetscStrlen(value,&len);CHKERRQ(ierr);
103       ierr = PetscDrawStringGetSize(draw,&w,NULL);CHKERRQ(ierr);
104       ierr = PetscDrawString(draw,xmax - len*w,ymin - .05*(ymax - ymin),PETSC_DRAW_BLACK,value);CHKERRQ(ierr);
105       ierr = PetscSNPrintf(value,16,"%0.2e",ymin);CHKERRQ(ierr);
106       ierr = PetscDrawString(draw,xmin - .05*(xmax - xmin),ymin,PETSC_DRAW_BLACK,value);CHKERRQ(ierr);
107       ierr = PetscSNPrintf(value,16,"%0.2e",ymax);CHKERRQ(ierr);
108       ierr = PetscDrawString(draw,xmin - .05*(xmax - xmin),ymax,PETSC_DRAW_BLACK,value);CHKERRQ(ierr);
109     }
110   }
111   ierr = PetscDrawCollectiveEnd(draw);CHKERRQ(ierr);
112   PetscFunctionReturn(0);
113 }
114 
115 PetscErrorCode VecView_MPI_Draw_DA2d(Vec xin,PetscViewer viewer)
116 {
117   DM                 da,dac,dag;
118   PetscErrorCode     ierr;
119   PetscInt           N,s,M,w,ncoors = 4;
120   const PetscInt     *lx,*ly;
121   PetscReal          coors[4];
122   PetscDraw          draw,popup;
123   PetscBool          isnull,useports = PETSC_FALSE;
124   MPI_Comm           comm;
125   Vec                xlocal,xcoor,xcoorl;
126   DMBoundaryType     bx,by;
127   DMDAStencilType    st;
128   ZoomCtx            zctx;
129   PetscDrawViewPorts *ports = NULL;
130   PetscViewerFormat  format;
131   PetscInt           *displayfields;
132   PetscInt           ndisplayfields,i,nbounds;
133   const PetscReal    *bounds;
134 
135   PetscFunctionBegin;
136   zctx.showgrid = PETSC_FALSE;
137   zctx.showaxis = PETSC_TRUE;
138 
139   ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
140   ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr);
141   if (isnull) PetscFunctionReturn(0);
142 
143   ierr = PetscViewerDrawGetBounds(viewer,&nbounds,&bounds);CHKERRQ(ierr);
144 
145   ierr = VecGetDM(xin,&da);CHKERRQ(ierr);
146   if (!da) SETERRQ(PetscObjectComm((PetscObject)xin),PETSC_ERR_ARG_WRONG,"Vector not generated from a DMDA");
147 
148   ierr = PetscObjectGetComm((PetscObject)xin,&comm);CHKERRQ(ierr);
149   ierr = MPI_Comm_rank(comm,&zctx.rank);CHKERRQ(ierr);
150 
151   ierr = DMDAGetInfo(da,0,&M,&N,0,&zctx.m,&zctx.n,0,&w,&s,&bx,&by,0,&st);CHKERRQ(ierr);
152   ierr = DMDAGetOwnershipRanges(da,&lx,&ly,NULL);CHKERRQ(ierr);
153 
154   /*
155      Obtain a sequential vector that is going to contain the local values plus ONE layer of
156      ghosted values to draw the graphics from. We also need its corresponding DMDA (dac) that will
157      update the local values pluse ONE layer of ghost values.
158   */
159   ierr = PetscObjectQuery((PetscObject)da,"GraphicsGhosted",(PetscObject*)&xlocal);CHKERRQ(ierr);
160   if (!xlocal) {
161     if (bx !=  DM_BOUNDARY_NONE || by !=  DM_BOUNDARY_NONE || s != 1 || st != DMDA_STENCIL_BOX) {
162       /*
163          if original da is not of stencil width one, or periodic or not a box stencil then
164          create a special DMDA to handle one level of ghost points for graphics
165       */
166       ierr = DMDACreate2d(comm,DM_BOUNDARY_NONE,DM_BOUNDARY_NONE,DMDA_STENCIL_BOX,M,N,zctx.m,zctx.n,w,1,lx,ly,&dac);CHKERRQ(ierr);
167       ierr = DMSetUp(dac);CHKERRQ(ierr);
168       ierr = PetscInfo(da,"Creating auxilary DMDA for managing graphics ghost points\n");CHKERRQ(ierr);
169     } else {
170       /* otherwise we can use the da we already have */
171       dac = da;
172     }
173     /* create local vector for holding ghosted values used in graphics */
174     ierr = DMCreateLocalVector(dac,&xlocal);CHKERRQ(ierr);
175     if (dac != da) {
176       /* don't keep any public reference of this DMDA, is is only available through xlocal */
177       ierr = PetscObjectDereference((PetscObject)dac);CHKERRQ(ierr);
178     } else {
179       /* remove association between xlocal and da, because below we compose in the opposite
180          direction and if we left this connect we'd get a loop, so the objects could
181          never be destroyed */
182       ierr = PetscObjectRemoveReference((PetscObject)xlocal,"__PETSc_dm");CHKERRQ(ierr);
183     }
184     ierr = PetscObjectCompose((PetscObject)da,"GraphicsGhosted",(PetscObject)xlocal);CHKERRQ(ierr);
185     ierr = PetscObjectDereference((PetscObject)xlocal);CHKERRQ(ierr);
186   } else {
187     if (bx !=  DM_BOUNDARY_NONE || by !=  DM_BOUNDARY_NONE || s != 1 || st != DMDA_STENCIL_BOX) {
188       ierr = VecGetDM(xlocal, &dac);CHKERRQ(ierr);
189     } else {
190       dac = da;
191     }
192   }
193 
194   /*
195       Get local (ghosted) values of vector
196   */
197   ierr = DMGlobalToLocalBegin(dac,xin,INSERT_VALUES,xlocal);CHKERRQ(ierr);
198   ierr = DMGlobalToLocalEnd(dac,xin,INSERT_VALUES,xlocal);CHKERRQ(ierr);
199   ierr = VecGetArrayRead(xlocal,&zctx.v);CHKERRQ(ierr);
200 
201   /*
202       Get coordinates of nodes
203   */
204   ierr = DMGetCoordinates(da,&xcoor);CHKERRQ(ierr);
205   if (!xcoor) {
206     ierr = DMDASetUniformCoordinates(da,0.0,1.0,0.0,1.0,0.0,0.0);CHKERRQ(ierr);
207     ierr = DMGetCoordinates(da,&xcoor);CHKERRQ(ierr);
208   }
209 
210   /*
211       Determine the min and max coordinates in plot
212   */
213   ierr = VecStrideMin(xcoor,0,NULL,&zctx.xmin);CHKERRQ(ierr);
214   ierr = VecStrideMax(xcoor,0,NULL,&zctx.xmax);CHKERRQ(ierr);
215   ierr = VecStrideMin(xcoor,1,NULL,&zctx.ymin);CHKERRQ(ierr);
216   ierr = VecStrideMax(xcoor,1,NULL,&zctx.ymax);CHKERRQ(ierr);
217   ierr = PetscOptionsGetBool(NULL,NULL,"-draw_contour_axis",&zctx.showaxis,NULL);CHKERRQ(ierr);
218   if (zctx.showaxis) {
219     coors[0] = zctx.xmin - .05*(zctx.xmax - zctx.xmin); coors[1] = zctx.ymin - .05*(zctx.ymax - zctx.ymin);
220     coors[2] = zctx.xmax + .05*(zctx.xmax - zctx.xmin); coors[3] = zctx.ymax + .05*(zctx.ymax - zctx.ymin);
221   } else {
222     coors[0] = zctx.xmin; coors[1] = zctx.ymin; coors[2] = zctx.xmax; coors[3] = zctx.ymax;
223   }
224   ierr = PetscOptionsGetRealArray(NULL,NULL,"-draw_coordinates",coors,&ncoors,NULL);CHKERRQ(ierr);
225   ierr = PetscInfo4(da,"Preparing DMDA 2d contour plot coordinates %g %g %g %g\n",(double)coors[0],(double)coors[1],(double)coors[2],(double)coors[3]);CHKERRQ(ierr);
226 
227   /*
228       Get local ghosted version of coordinates
229   */
230   ierr = PetscObjectQuery((PetscObject)da,"GraphicsCoordinateGhosted",(PetscObject*)&xcoorl);CHKERRQ(ierr);
231   if (!xcoorl) {
232     /* create DMDA to get local version of graphics */
233     ierr = DMDACreate2d(comm,DM_BOUNDARY_NONE,DM_BOUNDARY_NONE,DMDA_STENCIL_BOX,M,N,zctx.m,zctx.n,2,1,lx,ly,&dag);CHKERRQ(ierr);
234     ierr = DMSetUp(dag);CHKERRQ(ierr);
235     ierr = PetscInfo(dag,"Creating auxilary DMDA for managing graphics coordinates ghost points\n");CHKERRQ(ierr);
236     ierr = DMCreateLocalVector(dag,&xcoorl);CHKERRQ(ierr);
237     ierr = PetscObjectCompose((PetscObject)da,"GraphicsCoordinateGhosted",(PetscObject)xcoorl);CHKERRQ(ierr);
238     ierr = PetscObjectDereference((PetscObject)dag);CHKERRQ(ierr);
239     ierr = PetscObjectDereference((PetscObject)xcoorl);CHKERRQ(ierr);
240   } else {
241     ierr = VecGetDM(xcoorl,&dag);CHKERRQ(ierr);
242   }
243   ierr = DMGlobalToLocalBegin(dag,xcoor,INSERT_VALUES,xcoorl);CHKERRQ(ierr);
244   ierr = DMGlobalToLocalEnd(dag,xcoor,INSERT_VALUES,xcoorl);CHKERRQ(ierr);
245   ierr = VecGetArrayRead(xcoorl,&zctx.xy);CHKERRQ(ierr);
246   ierr = DMDAGetCoordinateName(da,0,&zctx.name0);CHKERRQ(ierr);
247   ierr = DMDAGetCoordinateName(da,1,&zctx.name1);CHKERRQ(ierr);
248 
249   /*
250       Get information about size of area each processor must do graphics for
251   */
252   ierr = DMDAGetInfo(dac,NULL,&M,&N,NULL,NULL,NULL,NULL,&zctx.dof,NULL,&bx,&by,NULL,NULL);CHKERRQ(ierr);
253   ierr = DMDAGetGhostCorners(dac,NULL,NULL,NULL,&zctx.m,&zctx.n,NULL);CHKERRQ(ierr);
254   ierr = PetscOptionsGetBool(NULL,NULL,"-draw_contour_grid",&zctx.showgrid,NULL);CHKERRQ(ierr);
255 
256   ierr = DMDASelectFields(da,&ndisplayfields,&displayfields);CHKERRQ(ierr);
257   ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
258   ierr = PetscOptionsGetBool(NULL,NULL,"-draw_ports",&useports,NULL);CHKERRQ(ierr);
259   if (format == PETSC_VIEWER_DRAW_PORTS) useports = PETSC_TRUE;
260   if (useports) {
261     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
262     ierr = PetscDrawCheckResizedWindow(draw);CHKERRQ(ierr);
263     ierr = PetscDrawClear(draw);CHKERRQ(ierr);
264     ierr = PetscDrawViewPortsCreate(draw,ndisplayfields,&ports);CHKERRQ(ierr);
265   }
266 
267   /*
268       Loop over each field; drawing each in a different window
269   */
270   for (i=0; i<ndisplayfields; i++) {
271     zctx.k = displayfields[i];
272 
273     /* determine the min and max value in plot */
274     ierr = VecStrideMin(xin,zctx.k,NULL,&zctx.min);CHKERRQ(ierr);
275     ierr = VecStrideMax(xin,zctx.k,NULL,&zctx.max);CHKERRQ(ierr);
276     if (zctx.k < nbounds) {
277       zctx.min = bounds[2*zctx.k];
278       zctx.max = bounds[2*zctx.k+1];
279     }
280     if (zctx.min == zctx.max) {
281       zctx.min -= 1.e-12;
282       zctx.max += 1.e-12;
283     }
284     ierr = PetscInfo2(da,"DMDA 2d contour plot min %g max %g\n",(double)zctx.min,(double)zctx.max);CHKERRQ(ierr);
285 
286     if (useports) {
287       ierr = PetscDrawViewPortsSet(ports,i);CHKERRQ(ierr);
288     } else {
289       const char *title;
290       ierr = PetscViewerDrawGetDraw(viewer,i,&draw);CHKERRQ(ierr);
291       ierr = DMDAGetFieldName(da,zctx.k,&title);CHKERRQ(ierr);
292       if (title) {ierr = PetscDrawSetTitle(draw,title);CHKERRQ(ierr);}
293     }
294 
295     ierr = PetscDrawGetPopup(draw,&popup);CHKERRQ(ierr);
296     ierr = PetscDrawScalePopup(popup,zctx.min,zctx.max);CHKERRQ(ierr);
297     ierr = PetscDrawSetCoordinates(draw,coors[0],coors[1],coors[2],coors[3]);CHKERRQ(ierr);
298     ierr = PetscDrawZoom(draw,VecView_MPI_Draw_DA2d_Zoom,&zctx);CHKERRQ(ierr);
299     if (!useports) {ierr = PetscDrawSave(draw);CHKERRQ(ierr);}
300   }
301   if (useports) {
302     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
303     ierr = PetscDrawSave(draw);CHKERRQ(ierr);
304   }
305 
306   ierr = PetscDrawViewPortsDestroy(ports);CHKERRQ(ierr);
307   ierr = PetscFree(displayfields);CHKERRQ(ierr);
308   ierr = VecRestoreArrayRead(xcoorl,&zctx.xy);CHKERRQ(ierr);
309   ierr = VecRestoreArrayRead(xlocal,&zctx.v);CHKERRQ(ierr);
310   PetscFunctionReturn(0);
311 }
312 
313 #if defined(PETSC_HAVE_HDF5)
314 static PetscErrorCode VecGetHDF5ChunkSize(DM_DA *da, Vec xin, PetscInt dimension, PetscInt timestep, hsize_t *chunkDims)
315 {
316   PetscMPIInt    comm_size;
317   PetscErrorCode ierr;
318   hsize_t        chunk_size, target_size, dim;
319   hsize_t        vec_size = sizeof(PetscScalar)*da->M*da->N*da->P*da->w;
320   hsize_t        avg_local_vec_size,KiB = 1024,MiB = KiB*KiB,GiB = MiB*KiB,min_size = MiB;
321   hsize_t        max_chunks = 64*KiB;                                              /* HDF5 internal limitation */
322   hsize_t        max_chunk_size = 4*GiB;                                           /* HDF5 internal limitation */
323   PetscInt       zslices=da->p, yslices=da->n, xslices=da->m;
324 
325   PetscFunctionBegin;
326   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)xin), &comm_size);CHKERRQ(ierr);
327   avg_local_vec_size = (hsize_t) ceil(vec_size*1.0/comm_size);      /* we will attempt to use this as the chunk size */
328 
329   target_size = (hsize_t) ceil(PetscMin(vec_size,PetscMin(max_chunk_size,PetscMax(avg_local_vec_size,PetscMax(ceil(vec_size*1.0/max_chunks),min_size)))));
330   /* following line uses sizeof(PetscReal) instead of sizeof(PetscScalar) because the last dimension of chunkDims[] captures the 2* when complex numbers are being used */
331   chunk_size = (hsize_t) PetscMax(1,chunkDims[0])*PetscMax(1,chunkDims[1])*PetscMax(1,chunkDims[2])*PetscMax(1,chunkDims[3])*PetscMax(1,chunkDims[4])*PetscMax(1,chunkDims[5])*sizeof(PetscReal);
332 
333   /*
334    if size/rank > max_chunk_size, we need radical measures: even going down to
335    avg_local_vec_size is not enough, so we simply use chunk size of 4 GiB no matter
336    what, composed in the most efficient way possible.
337    N.B. this minimises the number of chunks, which may or may not be the optimal
338    solution. In a BG, for example, the optimal solution is probably to make # chunks = #
339    IO nodes involved, but this author has no access to a BG to figure out how to
340    reliably find the right number. And even then it may or may not be enough.
341    */
342   if (avg_local_vec_size > max_chunk_size) {
343     /* check if we can just split local z-axis: is that enough? */
344     zslices = (PetscInt)ceil(vec_size*1.0/(da->p*max_chunk_size))*zslices;
345     if (zslices > da->P) {
346       /* lattice is too large in xy-directions, splitting z only is not enough */
347       zslices = da->P;
348       yslices= (PetscInt)ceil(vec_size*1.0/(zslices*da->n*max_chunk_size))*yslices;
349       if (yslices > da->N) {
350 	/* lattice is too large in x-direction, splitting along z, y is not enough */
351 	yslices = da->N;
352 	xslices= (PetscInt)ceil(vec_size*1.0/(zslices*yslices*da->m*max_chunk_size))*xslices;
353       }
354     }
355     dim = 0;
356     if (timestep >= 0) {
357       ++dim;
358     }
359     /* prefer to split z-axis, even down to planar slices */
360     if (dimension == 3) {
361       chunkDims[dim++] = (hsize_t) da->P/zslices;
362       chunkDims[dim++] = (hsize_t) da->N/yslices;
363       chunkDims[dim++] = (hsize_t) da->M/xslices;
364     } else {
365       /* This is a 2D world exceeding 4GiB in size; yes, I've seen them, even used myself */
366       chunkDims[dim++] = (hsize_t) da->N/yslices;
367       chunkDims[dim++] = (hsize_t) da->M/xslices;
368     }
369     chunk_size = (hsize_t) PetscMax(1,chunkDims[0])*PetscMax(1,chunkDims[1])*PetscMax(1,chunkDims[2])*PetscMax(1,chunkDims[3])*PetscMax(1,chunkDims[4])*PetscMax(1,chunkDims[5])*sizeof(double);
370   } else {
371     if (target_size < chunk_size) {
372       /* only change the defaults if target_size < chunk_size */
373       dim = 0;
374       if (timestep >= 0) {
375 	++dim;
376       }
377       /* prefer to split z-axis, even down to planar slices */
378       if (dimension == 3) {
379 	/* try splitting the z-axis to core-size bits, i.e. divide chunk size by # comm_size in z-direction */
380 	if (target_size >= chunk_size/da->p) {
381 	  /* just make chunks the size of <local_z>x<whole_world_y>x<whole_world_x>x<dof> */
382 	  chunkDims[dim] = (hsize_t) ceil(da->P*1.0/da->p);
383 	} else {
384 	  /* oops, just splitting the z-axis is NOT ENOUGH, need to split more; let's be
385            radical and let everyone write all they've got */
386 	  chunkDims[dim++] = (hsize_t) ceil(da->P*1.0/da->p);
387 	  chunkDims[dim++] = (hsize_t) ceil(da->N*1.0/da->n);
388 	  chunkDims[dim++] = (hsize_t) ceil(da->M*1.0/da->m);
389 	}
390       } else {
391 	/* This is a 2D world exceeding 4GiB in size; yes, I've seen them, even used myself */
392 	if (target_size >= chunk_size/da->n) {
393 	  /* just make chunks the size of <local_z>x<whole_world_y>x<whole_world_x>x<dof> */
394 	  chunkDims[dim] = (hsize_t) ceil(da->N*1.0/da->n);
395 	} else {
396 	  /* oops, just splitting the z-axis is NOT ENOUGH, need to split more; let's be
397 	   radical and let everyone write all they've got */
398 	  chunkDims[dim++] = (hsize_t) ceil(da->N*1.0/da->n);
399 	  chunkDims[dim++] = (hsize_t) ceil(da->M*1.0/da->m);
400 	}
401 
402       }
403       chunk_size = (hsize_t) PetscMax(1,chunkDims[0])*PetscMax(1,chunkDims[1])*PetscMax(1,chunkDims[2])*PetscMax(1,chunkDims[3])*PetscMax(1,chunkDims[4])*PetscMax(1,chunkDims[5])*sizeof(double);
404     } else {
405       /* precomputed chunks are fine, we don't need to do anything */
406     }
407   }
408   PetscFunctionReturn(0);
409 }
410 #endif
411 
412 #if defined(PETSC_HAVE_HDF5)
413 PetscErrorCode VecView_MPI_HDF5_DA(Vec xin,PetscViewer viewer)
414 {
415   DM                dm;
416   DM_DA             *da;
417   hid_t             filespace;  /* file dataspace identifier */
418   hid_t             chunkspace; /* chunk dataset property identifier */
419   hid_t             plist_id;   /* property list identifier */
420   hid_t             dset_id;    /* dataset identifier */
421   hid_t             memspace;   /* memory dataspace identifier */
422   hid_t             file_id;
423   hid_t             group;
424   hid_t             memscalartype; /* scalar type for mem (H5T_NATIVE_FLOAT or H5T_NATIVE_DOUBLE) */
425   hid_t             filescalartype; /* scalar type for file (H5T_NATIVE_FLOAT or H5T_NATIVE_DOUBLE) */
426   hsize_t           dim;
427   hsize_t           maxDims[6]={0}, dims[6]={0}, chunkDims[6]={0}, count[6]={0}, offset[6]={0}; /* we depend on these being sane later on  */
428   PetscInt          timestep, dimension;
429   const PetscScalar *x;
430   const char        *vecname;
431   PetscErrorCode    ierr;
432   PetscBool         dim2;
433   PetscBool         spoutput;
434 
435   PetscFunctionBegin;
436   ierr = PetscViewerHDF5OpenGroup(viewer, &file_id, &group);CHKERRQ(ierr);
437   ierr = PetscViewerHDF5GetTimestep(viewer, &timestep);CHKERRQ(ierr);
438   ierr = PetscViewerHDF5GetBaseDimension2(viewer,&dim2);CHKERRQ(ierr);
439   ierr = PetscViewerHDF5GetSPOutput(viewer,&spoutput);CHKERRQ(ierr);
440 
441   ierr = VecGetDM(xin,&dm);CHKERRQ(ierr);
442   if (!dm) SETERRQ(PetscObjectComm((PetscObject)xin),PETSC_ERR_ARG_WRONG,"Vector not generated from a DMDA");
443   da = (DM_DA*)dm->data;
444   ierr = DMGetDimension(dm, &dimension);CHKERRQ(ierr);
445 
446   /* Create the dataspace for the dataset.
447    *
448    * dims - holds the current dimensions of the dataset
449    *
450    * maxDims - holds the maximum dimensions of the dataset (unlimited
451    * for the number of time steps with the current dimensions for the
452    * other dimensions; so only additional time steps can be added).
453    *
454    * chunkDims - holds the size of a single time step (required to
455    * permit extending dataset).
456    */
457   dim = 0;
458   if (timestep >= 0) {
459     dims[dim]      = timestep+1;
460     maxDims[dim]   = H5S_UNLIMITED;
461     chunkDims[dim] = 1;
462     ++dim;
463   }
464   if (dimension == 3) {
465     ierr           = PetscHDF5IntCast(da->P,dims+dim);CHKERRQ(ierr);
466     maxDims[dim]   = dims[dim];
467     chunkDims[dim] = dims[dim];
468     ++dim;
469   }
470   if (dimension > 1) {
471     ierr           = PetscHDF5IntCast(da->N,dims+dim);CHKERRQ(ierr);
472     maxDims[dim]   = dims[dim];
473     chunkDims[dim] = dims[dim];
474     ++dim;
475   }
476   ierr           = PetscHDF5IntCast(da->M,dims+dim);CHKERRQ(ierr);
477   maxDims[dim]   = dims[dim];
478   chunkDims[dim] = dims[dim];
479   ++dim;
480   if (da->w > 1 || dim2) {
481     ierr           = PetscHDF5IntCast(da->w,dims+dim);CHKERRQ(ierr);
482     maxDims[dim]   = dims[dim];
483     chunkDims[dim] = dims[dim];
484     ++dim;
485   }
486 #if defined(PETSC_USE_COMPLEX)
487   dims[dim]      = 2;
488   maxDims[dim]   = dims[dim];
489   chunkDims[dim] = dims[dim];
490   ++dim;
491 #endif
492 
493   ierr = VecGetHDF5ChunkSize(da, xin, dimension, timestep, chunkDims); CHKERRQ(ierr);
494 
495   PetscStackCallHDF5Return(filespace,H5Screate_simple,(dim, dims, maxDims));
496 
497 #if defined(PETSC_USE_REAL_SINGLE)
498   memscalartype = H5T_NATIVE_FLOAT;
499   filescalartype = H5T_NATIVE_FLOAT;
500 #elif defined(PETSC_USE_REAL___FLOAT128)
501 #error "HDF5 output with 128 bit floats not supported."
502 #elif defined(PETSC_USE_REAL___FP16)
503 #error "HDF5 output with 16 bit floats not supported."
504 #else
505   memscalartype = H5T_NATIVE_DOUBLE;
506   if (spoutput == PETSC_TRUE) filescalartype = H5T_NATIVE_FLOAT;
507   else filescalartype = H5T_NATIVE_DOUBLE;
508 #endif
509 
510   /* Create the dataset with default properties and close filespace */
511   ierr = PetscObjectGetName((PetscObject)xin,&vecname);CHKERRQ(ierr);
512   if (!H5Lexists(group, vecname, H5P_DEFAULT)) {
513     /* Create chunk */
514     PetscStackCallHDF5Return(chunkspace,H5Pcreate,(H5P_DATASET_CREATE));
515     PetscStackCallHDF5(H5Pset_chunk,(chunkspace, dim, chunkDims));
516 
517     PetscStackCallHDF5Return(dset_id,H5Dcreate2,(group, vecname, filescalartype, filespace, H5P_DEFAULT, chunkspace, H5P_DEFAULT));
518   } else {
519     PetscStackCallHDF5Return(dset_id,H5Dopen2,(group, vecname, H5P_DEFAULT));
520     PetscStackCallHDF5(H5Dset_extent,(dset_id, dims));
521   }
522   PetscStackCallHDF5(H5Sclose,(filespace));
523 
524   /* Each process defines a dataset and writes it to the hyperslab in the file */
525   dim = 0;
526   if (timestep >= 0) {
527     offset[dim] = timestep;
528     ++dim;
529   }
530   if (dimension == 3) {ierr = PetscHDF5IntCast(da->zs,offset + dim++);CHKERRQ(ierr);}
531   if (dimension > 1)  {ierr = PetscHDF5IntCast(da->ys,offset + dim++);CHKERRQ(ierr);}
532   ierr = PetscHDF5IntCast(da->xs/da->w,offset + dim++);CHKERRQ(ierr);
533   if (da->w > 1 || dim2) offset[dim++] = 0;
534 #if defined(PETSC_USE_COMPLEX)
535   offset[dim++] = 0;
536 #endif
537   dim = 0;
538   if (timestep >= 0) {
539     count[dim] = 1;
540     ++dim;
541   }
542   if (dimension == 3) {ierr = PetscHDF5IntCast(da->ze - da->zs,count + dim++);CHKERRQ(ierr);}
543   if (dimension > 1)  {ierr = PetscHDF5IntCast(da->ye - da->ys,count + dim++);CHKERRQ(ierr);}
544   ierr = PetscHDF5IntCast((da->xe - da->xs)/da->w,count + dim++);CHKERRQ(ierr);
545   if (da->w > 1 || dim2) {ierr = PetscHDF5IntCast(da->w,count + dim++);CHKERRQ(ierr);}
546 #if defined(PETSC_USE_COMPLEX)
547   count[dim++] = 2;
548 #endif
549   PetscStackCallHDF5Return(memspace,H5Screate_simple,(dim, count, NULL));
550   PetscStackCallHDF5Return(filespace,H5Dget_space,(dset_id));
551   PetscStackCallHDF5(H5Sselect_hyperslab,(filespace, H5S_SELECT_SET, offset, NULL, count, NULL));
552 
553   /* Create property list for collective dataset write */
554   PetscStackCallHDF5Return(plist_id,H5Pcreate,(H5P_DATASET_XFER));
555 #if defined(PETSC_HAVE_H5PSET_FAPL_MPIO)
556   PetscStackCallHDF5(H5Pset_dxpl_mpio,(plist_id, H5FD_MPIO_COLLECTIVE));
557 #endif
558   /* To write dataset independently use H5Pset_dxpl_mpio(plist_id, H5FD_MPIO_INDEPENDENT) */
559 
560   ierr   = VecGetArrayRead(xin, &x);CHKERRQ(ierr);
561   PetscStackCallHDF5(H5Dwrite,(dset_id, memscalartype, memspace, filespace, plist_id, x));
562   PetscStackCallHDF5(H5Fflush,(file_id, H5F_SCOPE_GLOBAL));
563   ierr   = VecRestoreArrayRead(xin, &x);CHKERRQ(ierr);
564 
565   /* Close/release resources */
566   if (group != file_id) {
567     PetscStackCallHDF5(H5Gclose,(group));
568   }
569   PetscStackCallHDF5(H5Pclose,(plist_id));
570   PetscStackCallHDF5(H5Sclose,(filespace));
571   PetscStackCallHDF5(H5Sclose,(memspace));
572   PetscStackCallHDF5(H5Dclose,(dset_id));
573   ierr   = PetscInfo1(xin,"Wrote Vec object with name %s\n",vecname);CHKERRQ(ierr);
574   PetscFunctionReturn(0);
575 }
576 #endif
577 
578 extern PetscErrorCode VecView_MPI_Draw_DA1d(Vec,PetscViewer);
579 
580 #if defined(PETSC_HAVE_MPIIO)
581 static PetscErrorCode DMDAArrayMPIIO(DM da,PetscViewer viewer,Vec xin,PetscBool write)
582 {
583   PetscErrorCode    ierr;
584   MPI_File          mfdes;
585   PetscMPIInt       gsizes[4],lsizes[4],lstarts[4],asiz,dof;
586   MPI_Datatype      view;
587   const PetscScalar *array;
588   MPI_Offset        off;
589   MPI_Aint          ub,ul;
590   PetscInt          type,rows,vecrows,tr[2];
591   DM_DA             *dd = (DM_DA*)da->data;
592   PetscBool         skipheader;
593 
594   PetscFunctionBegin;
595   ierr = VecGetSize(xin,&vecrows);CHKERRQ(ierr);
596   ierr = PetscViewerBinaryGetSkipHeader(viewer,&skipheader);CHKERRQ(ierr);
597   if (!write) {
598     /* Read vector header. */
599     if (!skipheader) {
600       ierr = PetscViewerBinaryRead(viewer,tr,2,NULL,PETSC_INT);CHKERRQ(ierr);
601       type = tr[0];
602       rows = tr[1];
603       if (type != VEC_FILE_CLASSID) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_WRONG,"Not vector next in file");
604       if (rows != vecrows) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_SIZ,"Vector in file not same size as DMDA vector");
605     }
606   } else {
607     tr[0] = VEC_FILE_CLASSID;
608     tr[1] = vecrows;
609     if (!skipheader) {
610       ierr  = PetscViewerBinaryWrite(viewer,tr,2,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
611     }
612   }
613 
614   ierr       = PetscMPIIntCast(dd->w,&dof);CHKERRQ(ierr);
615   gsizes[0]  = dof;
616   ierr       = PetscMPIIntCast(dd->M,gsizes+1);CHKERRQ(ierr);
617   ierr       = PetscMPIIntCast(dd->N,gsizes+2);CHKERRQ(ierr);
618   ierr       = PetscMPIIntCast(dd->P,gsizes+3);CHKERRQ(ierr);
619   lsizes[0]  = dof;
620   ierr       = PetscMPIIntCast((dd->xe-dd->xs)/dof,lsizes+1);CHKERRQ(ierr);
621   ierr       = PetscMPIIntCast(dd->ye-dd->ys,lsizes+2);CHKERRQ(ierr);
622   ierr       = PetscMPIIntCast(dd->ze-dd->zs,lsizes+3);CHKERRQ(ierr);
623   lstarts[0] = 0;
624   ierr       = PetscMPIIntCast(dd->xs/dof,lstarts+1);CHKERRQ(ierr);
625   ierr       = PetscMPIIntCast(dd->ys,lstarts+2);CHKERRQ(ierr);
626   ierr       = PetscMPIIntCast(dd->zs,lstarts+3);CHKERRQ(ierr);
627   ierr       = MPI_Type_create_subarray(da->dim+1,gsizes,lsizes,lstarts,MPI_ORDER_FORTRAN,MPIU_SCALAR,&view);CHKERRQ(ierr);
628   ierr       = MPI_Type_commit(&view);CHKERRQ(ierr);
629 
630   ierr = PetscViewerBinaryGetMPIIODescriptor(viewer,&mfdes);CHKERRQ(ierr);
631   ierr = PetscViewerBinaryGetMPIIOOffset(viewer,&off);CHKERRQ(ierr);
632   ierr = MPI_File_set_view(mfdes,off,MPIU_SCALAR,view,(char*)"native",MPI_INFO_NULL);CHKERRQ(ierr);
633   ierr = VecGetArrayRead(xin,&array);CHKERRQ(ierr);
634   asiz = lsizes[1]*(lsizes[2] > 0 ? lsizes[2] : 1)*(lsizes[3] > 0 ? lsizes[3] : 1)*dof;
635   if (write) {
636     ierr = MPIU_File_write_all(mfdes,(PetscScalar*)array,asiz,MPIU_SCALAR,MPI_STATUS_IGNORE);CHKERRQ(ierr);
637   } else {
638     ierr = MPIU_File_read_all(mfdes,(PetscScalar*)array,asiz,MPIU_SCALAR,MPI_STATUS_IGNORE);CHKERRQ(ierr);
639   }
640   ierr = MPI_Type_get_extent(view,&ul,&ub);CHKERRQ(ierr);
641   ierr = PetscViewerBinaryAddMPIIOOffset(viewer,ub);CHKERRQ(ierr);
642   ierr = VecRestoreArrayRead(xin,&array);CHKERRQ(ierr);
643   ierr = MPI_Type_free(&view);CHKERRQ(ierr);
644   PetscFunctionReturn(0);
645 }
646 #endif
647 
648 PetscErrorCode  VecView_MPI_DA(Vec xin,PetscViewer viewer)
649 {
650   DM                da;
651   PetscErrorCode    ierr;
652   PetscInt          dim;
653   Vec               natural;
654   PetscBool         isdraw,isvtk,isglvis;
655 #if defined(PETSC_HAVE_HDF5)
656   PetscBool         ishdf5;
657 #endif
658   const char        *prefix,*name;
659   PetscViewerFormat format;
660 
661   PetscFunctionBegin;
662   ierr = VecGetDM(xin,&da);CHKERRQ(ierr);
663   if (!da) SETERRQ(PetscObjectComm((PetscObject)xin),PETSC_ERR_ARG_WRONG,"Vector not generated from a DMDA");
664   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
665   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERVTK,&isvtk);CHKERRQ(ierr);
666 #if defined(PETSC_HAVE_HDF5)
667   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERHDF5,&ishdf5);CHKERRQ(ierr);
668 #endif
669   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERGLVIS,&isglvis);CHKERRQ(ierr);
670   if (isdraw) {
671     ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr);
672     if (dim == 1) {
673       ierr = VecView_MPI_Draw_DA1d(xin,viewer);CHKERRQ(ierr);
674     } else if (dim == 2) {
675       ierr = VecView_MPI_Draw_DA2d(xin,viewer);CHKERRQ(ierr);
676     } else SETERRQ1(PetscObjectComm((PetscObject)da),PETSC_ERR_SUP,"Cannot graphically view vector associated with this dimensional DMDA %D",dim);
677   } else if (isvtk) {           /* Duplicate the Vec */
678     Vec Y;
679     ierr = VecDuplicate(xin,&Y);CHKERRQ(ierr);
680     if (((PetscObject)xin)->name) {
681       /* If xin was named, copy the name over to Y. The duplicate names are safe because nobody else will ever see Y. */
682       ierr = PetscObjectSetName((PetscObject)Y,((PetscObject)xin)->name);CHKERRQ(ierr);
683     }
684     ierr = VecCopy(xin,Y);CHKERRQ(ierr);
685     {
686       PetscObject dmvtk;
687       PetscBool   compatible,compatibleSet;
688       ierr = PetscViewerVTKGetDM(viewer,&dmvtk);CHKERRQ(ierr);
689       if (dmvtk) {
690         PetscValidHeaderSpecific((DM)dmvtk,DM_CLASSID,-1);
691         ierr = DMGetCompatibility(da,(DM)dmvtk,&compatible,&compatibleSet);CHKERRQ(ierr);
692         if (!compatibleSet || !compatible) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_INCOMP,"Cannot confirm compatibility of DMs associated with Vecs viewed in the same VTK file. Check that grids are the same.");
693       }
694       ierr = PetscViewerVTKAddField(viewer,(PetscObject)da,DMDAVTKWriteAll,PETSC_VTK_POINT_FIELD,PETSC_FALSE,(PetscObject)Y);CHKERRQ(ierr);
695     }
696 #if defined(PETSC_HAVE_HDF5)
697   } else if (ishdf5) {
698     ierr = VecView_MPI_HDF5_DA(xin,viewer);CHKERRQ(ierr);
699 #endif
700   } else if (isglvis) {
701     ierr = VecView_GLVis(xin,viewer);CHKERRQ(ierr);
702   } else {
703 #if defined(PETSC_HAVE_MPIIO)
704     PetscBool isbinary,isMPIIO;
705 
706     ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
707     if (isbinary) {
708       ierr = PetscViewerBinaryGetUseMPIIO(viewer,&isMPIIO);CHKERRQ(ierr);
709       if (isMPIIO) {
710         ierr = DMDAArrayMPIIO(da,viewer,xin,PETSC_TRUE);CHKERRQ(ierr);
711         PetscFunctionReturn(0);
712       }
713     }
714 #endif
715 
716     /* call viewer on natural ordering */
717     ierr = PetscObjectGetOptionsPrefix((PetscObject)xin,&prefix);CHKERRQ(ierr);
718     ierr = DMDACreateNaturalVector(da,&natural);CHKERRQ(ierr);
719     ierr = PetscObjectSetOptionsPrefix((PetscObject)natural,prefix);CHKERRQ(ierr);
720     ierr = DMDAGlobalToNaturalBegin(da,xin,INSERT_VALUES,natural);CHKERRQ(ierr);
721     ierr = DMDAGlobalToNaturalEnd(da,xin,INSERT_VALUES,natural);CHKERRQ(ierr);
722     ierr = PetscObjectGetName((PetscObject)xin,&name);CHKERRQ(ierr);
723     ierr = PetscObjectSetName((PetscObject)natural,name);CHKERRQ(ierr);
724 
725     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
726     if (format == PETSC_VIEWER_BINARY_MATLAB) {
727       /* temporarily remove viewer format so it won't trigger in the VecView() */
728       ierr = PetscViewerPushFormat(viewer,PETSC_VIEWER_DEFAULT);CHKERRQ(ierr);
729     }
730 
731     ((PetscObject)natural)->donotPetscObjectPrintClassNamePrefixType = PETSC_TRUE;
732     ierr = VecView(natural,viewer);CHKERRQ(ierr);
733     ((PetscObject)natural)->donotPetscObjectPrintClassNamePrefixType = PETSC_FALSE;
734 
735     if (format == PETSC_VIEWER_BINARY_MATLAB) {
736       MPI_Comm    comm;
737       FILE        *info;
738       const char  *fieldname;
739       char        fieldbuf[256];
740       PetscInt    dim,ni,nj,nk,pi,pj,pk,dof,n;
741 
742       /* set the viewer format back into the viewer */
743       ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
744       ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
745       ierr = PetscViewerBinaryGetInfoPointer(viewer,&info);CHKERRQ(ierr);
746       ierr = DMDAGetInfo(da,&dim,&ni,&nj,&nk,&pi,&pj,&pk,&dof,0,0,0,0,0);CHKERRQ(ierr);
747       ierr = PetscFPrintf(comm,info,"#--- begin code written by PetscViewerBinary for MATLAB format ---#\n");CHKERRQ(ierr);
748       ierr = PetscFPrintf(comm,info,"#$$ tmp = PetscBinaryRead(fd); \n");CHKERRQ(ierr);
749       if (dim == 1) { ierr = PetscFPrintf(comm,info,"#$$ tmp = reshape(tmp,%d,%d);\n",dof,ni);CHKERRQ(ierr); }
750       if (dim == 2) { ierr = PetscFPrintf(comm,info,"#$$ tmp = reshape(tmp,%d,%d,%d);\n",dof,ni,nj);CHKERRQ(ierr); }
751       if (dim == 3) { ierr = PetscFPrintf(comm,info,"#$$ tmp = reshape(tmp,%d,%d,%d,%d);\n",dof,ni,nj,nk);CHKERRQ(ierr); }
752 
753       for (n=0; n<dof; n++) {
754         ierr = DMDAGetFieldName(da,n,&fieldname);CHKERRQ(ierr);
755         if (!fieldname || !fieldname[0]) {
756           ierr = PetscSNPrintf(fieldbuf,sizeof fieldbuf,"field%D",n);CHKERRQ(ierr);
757           fieldname = fieldbuf;
758         }
759         if (dim == 1) { ierr = PetscFPrintf(comm,info,"#$$ Set.%s.%s = squeeze(tmp(%d,:))';\n",name,fieldname,n+1);CHKERRQ(ierr); }
760         if (dim == 2) { ierr = PetscFPrintf(comm,info,"#$$ Set.%s.%s = squeeze(tmp(%d,:,:))';\n",name,fieldname,n+1);CHKERRQ(ierr); }
761         if (dim == 3) { ierr = PetscFPrintf(comm,info,"#$$ Set.%s.%s = permute(squeeze(tmp(%d,:,:,:)),[2 1 3]);\n",name,fieldname,n+1);CHKERRQ(ierr);}
762       }
763       ierr = PetscFPrintf(comm,info,"#$$ clear tmp; \n");CHKERRQ(ierr);
764       ierr = PetscFPrintf(comm,info,"#--- end code written by PetscViewerBinary for MATLAB format ---#\n\n");CHKERRQ(ierr);
765     }
766 
767     ierr = VecDestroy(&natural);CHKERRQ(ierr);
768   }
769   PetscFunctionReturn(0);
770 }
771 
772 #if defined(PETSC_HAVE_HDF5)
773 PetscErrorCode VecLoad_HDF5_DA(Vec xin, PetscViewer viewer)
774 {
775   DM             da;
776   PetscErrorCode ierr;
777   hsize_t        dim,rdim;
778   hsize_t        dims[6]={0},count[6]={0},offset[6]={0};
779   PetscInt       dimension,timestep,dofInd;
780   PetscScalar    *x;
781   const char     *vecname;
782   hid_t          filespace; /* file dataspace identifier */
783   hid_t          plist_id;  /* property list identifier */
784   hid_t          dset_id;   /* dataset identifier */
785   hid_t          memspace;  /* memory dataspace identifier */
786   hid_t          file_id,group;
787   hid_t          scalartype; /* scalar type (H5T_NATIVE_FLOAT or H5T_NATIVE_DOUBLE) */
788   DM_DA          *dd;
789   PetscBool      dim2 = PETSC_FALSE;
790 
791   PetscFunctionBegin;
792 #if defined(PETSC_USE_REAL_SINGLE)
793   scalartype = H5T_NATIVE_FLOAT;
794 #elif defined(PETSC_USE_REAL___FLOAT128)
795 #error "HDF5 output with 128 bit floats not supported."
796 #elif defined(PETSC_USE_REAL___FP16)
797 #error "HDF5 output with 16 bit floats not supported."
798 #else
799   scalartype = H5T_NATIVE_DOUBLE;
800 #endif
801 
802   ierr = PetscViewerHDF5OpenGroup(viewer, &file_id, &group);CHKERRQ(ierr);
803   ierr = PetscViewerHDF5GetTimestep(viewer, &timestep);CHKERRQ(ierr);
804   ierr = PetscObjectGetName((PetscObject)xin,&vecname);CHKERRQ(ierr);
805   ierr = VecGetDM(xin,&da);CHKERRQ(ierr);
806   dd   = (DM_DA*)da->data;
807   ierr = DMGetDimension(da, &dimension);CHKERRQ(ierr);
808 
809   /* Open dataset */
810   PetscStackCallHDF5Return(dset_id,H5Dopen2,(group, vecname, H5P_DEFAULT));
811 
812   /* Retrieve the dataspace for the dataset */
813   PetscStackCallHDF5Return(filespace,H5Dget_space,(dset_id));
814   PetscStackCallHDF5Return(rdim,H5Sget_simple_extent_dims,(filespace, dims, NULL));
815 
816   /* Expected dimension for holding the dof's */
817 #if defined(PETSC_USE_COMPLEX)
818   dofInd = rdim-2;
819 #else
820   dofInd = rdim-1;
821 #endif
822 
823   /* The expected number of dimensions, assuming basedimension2 = false */
824   dim = dimension;
825   if (dd->w > 1) ++dim;
826   if (timestep >= 0) ++dim;
827 #if defined(PETSC_USE_COMPLEX)
828   ++dim;
829 #endif
830 
831   /* In this case the input dataset have one extra, unexpected dimension. */
832   if (rdim == dim+1) {
833     /* In this case the block size unity */
834     if (dd->w == 1 && dims[dofInd] == 1) dim2 = PETSC_TRUE;
835 
836     /* Special error message for the case where dof does not match the input file */
837     else if (dd->w != (PetscInt) dims[dofInd]) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Number of dofs in file is %D, not %D as expected",(PetscInt)dims[dofInd],dd->w);
838 
839   /* Other cases where rdim != dim cannot be handled currently */
840   } else if (rdim != dim) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Dimension of array in file is %d, not %d as expected with dof = %D",rdim,dim,dd->w);
841 
842   /* Set up the hyperslab size */
843   dim = 0;
844   if (timestep >= 0) {
845     offset[dim] = timestep;
846     count[dim] = 1;
847     ++dim;
848   }
849   if (dimension == 3) {
850     ierr = PetscHDF5IntCast(dd->zs,offset + dim);CHKERRQ(ierr);
851     ierr = PetscHDF5IntCast(dd->ze - dd->zs,count + dim);CHKERRQ(ierr);
852     ++dim;
853   }
854   if (dimension > 1) {
855     ierr = PetscHDF5IntCast(dd->ys,offset + dim);CHKERRQ(ierr);
856     ierr = PetscHDF5IntCast(dd->ye - dd->ys,count + dim);CHKERRQ(ierr);
857     ++dim;
858   }
859   ierr = PetscHDF5IntCast(dd->xs/dd->w,offset + dim);CHKERRQ(ierr);
860   ierr = PetscHDF5IntCast((dd->xe - dd->xs)/dd->w,count + dim);CHKERRQ(ierr);
861   ++dim;
862   if (dd->w > 1 || dim2) {
863     offset[dim] = 0;
864     ierr = PetscHDF5IntCast(dd->w,count + dim);CHKERRQ(ierr);
865     ++dim;
866   }
867 #if defined(PETSC_USE_COMPLEX)
868   offset[dim] = 0;
869   count[dim] = 2;
870   ++dim;
871 #endif
872 
873   /* Create the memory and filespace */
874   PetscStackCallHDF5Return(memspace,H5Screate_simple,(dim, count, NULL));
875   PetscStackCallHDF5(H5Sselect_hyperslab,(filespace, H5S_SELECT_SET, offset, NULL, count, NULL));
876 
877   /* Create property list for collective dataset write */
878   PetscStackCallHDF5Return(plist_id,H5Pcreate,(H5P_DATASET_XFER));
879 #if defined(PETSC_HAVE_H5PSET_FAPL_MPIO)
880   PetscStackCallHDF5(H5Pset_dxpl_mpio,(plist_id, H5FD_MPIO_COLLECTIVE));
881 #endif
882   /* To read dataset independently use H5Pset_dxpl_mpio(plist_id, H5FD_MPIO_INDEPENDENT) */
883 
884   ierr   = VecGetArray(xin, &x);CHKERRQ(ierr);
885   PetscStackCallHDF5(H5Dread,(dset_id, scalartype, memspace, filespace, plist_id, x));
886   ierr   = VecRestoreArray(xin, &x);CHKERRQ(ierr);
887 
888   /* Close/release resources */
889   if (group != file_id) {
890     PetscStackCallHDF5(H5Gclose,(group));
891   }
892   PetscStackCallHDF5(H5Pclose,(plist_id));
893   PetscStackCallHDF5(H5Sclose,(filespace));
894   PetscStackCallHDF5(H5Sclose,(memspace));
895   PetscStackCallHDF5(H5Dclose,(dset_id));
896   PetscFunctionReturn(0);
897 }
898 #endif
899 
900 PetscErrorCode VecLoad_Binary_DA(Vec xin, PetscViewer viewer)
901 {
902   DM             da;
903   PetscErrorCode ierr;
904   Vec            natural;
905   const char     *prefix;
906   PetscInt       bs;
907   PetscBool      flag;
908   DM_DA          *dd;
909 #if defined(PETSC_HAVE_MPIIO)
910   PetscBool isMPIIO;
911 #endif
912 
913   PetscFunctionBegin;
914   ierr = VecGetDM(xin,&da);CHKERRQ(ierr);
915   dd   = (DM_DA*)da->data;
916 #if defined(PETSC_HAVE_MPIIO)
917   ierr = PetscViewerBinaryGetUseMPIIO(viewer,&isMPIIO);CHKERRQ(ierr);
918   if (isMPIIO) {
919     ierr = DMDAArrayMPIIO(da,viewer,xin,PETSC_FALSE);CHKERRQ(ierr);
920     PetscFunctionReturn(0);
921   }
922 #endif
923 
924   ierr = PetscObjectGetOptionsPrefix((PetscObject)xin,&prefix);CHKERRQ(ierr);
925   ierr = DMDACreateNaturalVector(da,&natural);CHKERRQ(ierr);
926   ierr = PetscObjectSetName((PetscObject)natural,((PetscObject)xin)->name);CHKERRQ(ierr);
927   ierr = PetscObjectSetOptionsPrefix((PetscObject)natural,prefix);CHKERRQ(ierr);
928   ierr = VecLoad(natural,viewer);CHKERRQ(ierr);
929   ierr = DMDANaturalToGlobalBegin(da,natural,INSERT_VALUES,xin);CHKERRQ(ierr);
930   ierr = DMDANaturalToGlobalEnd(da,natural,INSERT_VALUES,xin);CHKERRQ(ierr);
931   ierr = VecDestroy(&natural);CHKERRQ(ierr);
932   ierr = PetscInfo(xin,"Loading vector from natural ordering into DMDA\n");CHKERRQ(ierr);
933   ierr = PetscOptionsGetInt(NULL,((PetscObject)xin)->prefix,"-vecload_block_size",&bs,&flag);CHKERRQ(ierr);
934   if (flag && bs != dd->w) {
935     ierr = PetscInfo2(xin,"Block size in file %D not equal to DMDA's dof %D\n",bs,dd->w);CHKERRQ(ierr);
936   }
937   PetscFunctionReturn(0);
938 }
939 
940 PetscErrorCode  VecLoad_Default_DA(Vec xin, PetscViewer viewer)
941 {
942   PetscErrorCode ierr;
943   DM             da;
944   PetscBool      isbinary;
945 #if defined(PETSC_HAVE_HDF5)
946   PetscBool ishdf5;
947 #endif
948 
949   PetscFunctionBegin;
950   ierr = VecGetDM(xin,&da);CHKERRQ(ierr);
951   if (!da) SETERRQ(PetscObjectComm((PetscObject)xin),PETSC_ERR_ARG_WRONG,"Vector not generated from a DMDA");
952 
953 #if defined(PETSC_HAVE_HDF5)
954   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERHDF5,&ishdf5);CHKERRQ(ierr);
955 #endif
956   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
957 
958   if (isbinary) {
959     ierr = VecLoad_Binary_DA(xin,viewer);CHKERRQ(ierr);
960 #if defined(PETSC_HAVE_HDF5)
961   } else if (ishdf5) {
962     ierr = VecLoad_HDF5_DA(xin,viewer);CHKERRQ(ierr);
963 #endif
964   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Viewer type %s not supported for vector loading", ((PetscObject)viewer)->type_name);
965   PetscFunctionReturn(0);
966 }
967