xref: /petsc/src/dm/impls/da/gr2.c (revision 80153354bc763d7777ef13196fd03cfc4d2e02f9)
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 #if (H5_VERS_MAJOR * 10000 + H5_VERS_MINOR * 100 + H5_VERS_RELEASE >= 10800)
518     PetscStackCallHDF5Return(dset_id,H5Dcreate2,(group, vecname, filescalartype, filespace, H5P_DEFAULT, chunkspace, H5P_DEFAULT));
519 #else
520     PetscStackCallHDF5Return(dset_id,H5Dcreate,(group, vecname, filescalartype, filespace, H5P_DEFAULT));
521 #endif
522   } else {
523     PetscStackCallHDF5Return(dset_id,H5Dopen2,(group, vecname, H5P_DEFAULT));
524     PetscStackCallHDF5(H5Dset_extent,(dset_id, dims));
525   }
526   PetscStackCallHDF5(H5Sclose,(filespace));
527 
528   /* Each process defines a dataset and writes it to the hyperslab in the file */
529   dim = 0;
530   if (timestep >= 0) {
531     offset[dim] = timestep;
532     ++dim;
533   }
534   if (dimension == 3) {ierr = PetscHDF5IntCast(da->zs,offset + dim++);CHKERRQ(ierr);}
535   if (dimension > 1)  {ierr = PetscHDF5IntCast(da->ys,offset + dim++);CHKERRQ(ierr);}
536   ierr = PetscHDF5IntCast(da->xs/da->w,offset + dim++);CHKERRQ(ierr);
537   if (da->w > 1 || dim2) offset[dim++] = 0;
538 #if defined(PETSC_USE_COMPLEX)
539   offset[dim++] = 0;
540 #endif
541   dim = 0;
542   if (timestep >= 0) {
543     count[dim] = 1;
544     ++dim;
545   }
546   if (dimension == 3) {ierr = PetscHDF5IntCast(da->ze - da->zs,count + dim++);CHKERRQ(ierr);}
547   if (dimension > 1)  {ierr = PetscHDF5IntCast(da->ye - da->ys,count + dim++);CHKERRQ(ierr);}
548   ierr = PetscHDF5IntCast((da->xe - da->xs)/da->w,count + dim++);CHKERRQ(ierr);
549   if (da->w > 1 || dim2) {ierr = PetscHDF5IntCast(da->w,count + dim++);CHKERRQ(ierr);}
550 #if defined(PETSC_USE_COMPLEX)
551   count[dim++] = 2;
552 #endif
553   PetscStackCallHDF5Return(memspace,H5Screate_simple,(dim, count, NULL));
554   PetscStackCallHDF5Return(filespace,H5Dget_space,(dset_id));
555   PetscStackCallHDF5(H5Sselect_hyperslab,(filespace, H5S_SELECT_SET, offset, NULL, count, NULL));
556 
557   /* Create property list for collective dataset write */
558   PetscStackCallHDF5Return(plist_id,H5Pcreate,(H5P_DATASET_XFER));
559 #if defined(PETSC_HAVE_H5PSET_FAPL_MPIO)
560   PetscStackCallHDF5(H5Pset_dxpl_mpio,(plist_id, H5FD_MPIO_COLLECTIVE));
561 #endif
562   /* To write dataset independently use H5Pset_dxpl_mpio(plist_id, H5FD_MPIO_INDEPENDENT) */
563 
564   ierr   = VecGetArrayRead(xin, &x);CHKERRQ(ierr);
565   PetscStackCallHDF5(H5Dwrite,(dset_id, memscalartype, memspace, filespace, plist_id, x));
566   PetscStackCallHDF5(H5Fflush,(file_id, H5F_SCOPE_GLOBAL));
567   ierr   = VecRestoreArrayRead(xin, &x);CHKERRQ(ierr);
568 
569   /* Close/release resources */
570   if (group != file_id) {
571     PetscStackCallHDF5(H5Gclose,(group));
572   }
573   PetscStackCallHDF5(H5Pclose,(plist_id));
574   PetscStackCallHDF5(H5Sclose,(filespace));
575   PetscStackCallHDF5(H5Sclose,(memspace));
576   PetscStackCallHDF5(H5Dclose,(dset_id));
577   ierr   = PetscInfo1(xin,"Wrote Vec object with name %s\n",vecname);CHKERRQ(ierr);
578   PetscFunctionReturn(0);
579 }
580 #endif
581 
582 extern PetscErrorCode VecView_MPI_Draw_DA1d(Vec,PetscViewer);
583 
584 #if defined(PETSC_HAVE_MPIIO)
585 static PetscErrorCode DMDAArrayMPIIO(DM da,PetscViewer viewer,Vec xin,PetscBool write)
586 {
587   PetscErrorCode    ierr;
588   MPI_File          mfdes;
589   PetscMPIInt       gsizes[4],lsizes[4],lstarts[4],asiz,dof;
590   MPI_Datatype      view;
591   const PetscScalar *array;
592   MPI_Offset        off;
593   MPI_Aint          ub,ul;
594   PetscInt          type,rows,vecrows,tr[2];
595   DM_DA             *dd = (DM_DA*)da->data;
596   PetscBool         skipheader;
597 
598   PetscFunctionBegin;
599   ierr = VecGetSize(xin,&vecrows);CHKERRQ(ierr);
600   ierr = PetscViewerBinaryGetSkipHeader(viewer,&skipheader);CHKERRQ(ierr);
601   if (!write) {
602     /* Read vector header. */
603     if (!skipheader) {
604       ierr = PetscViewerBinaryRead(viewer,tr,2,NULL,PETSC_INT);CHKERRQ(ierr);
605       type = tr[0];
606       rows = tr[1];
607       if (type != VEC_FILE_CLASSID) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_WRONG,"Not vector next in file");
608       if (rows != vecrows) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_SIZ,"Vector in file not same size as DMDA vector");
609     }
610   } else {
611     tr[0] = VEC_FILE_CLASSID;
612     tr[1] = vecrows;
613     if (!skipheader) {
614       ierr  = PetscViewerBinaryWrite(viewer,tr,2,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
615     }
616   }
617 
618   ierr       = PetscMPIIntCast(dd->w,&dof);CHKERRQ(ierr);
619   gsizes[0]  = dof;
620   ierr       = PetscMPIIntCast(dd->M,gsizes+1);CHKERRQ(ierr);
621   ierr       = PetscMPIIntCast(dd->N,gsizes+2);CHKERRQ(ierr);
622   ierr       = PetscMPIIntCast(dd->P,gsizes+3);CHKERRQ(ierr);
623   lsizes[0]  = dof;
624   ierr       = PetscMPIIntCast((dd->xe-dd->xs)/dof,lsizes+1);CHKERRQ(ierr);
625   ierr       = PetscMPIIntCast(dd->ye-dd->ys,lsizes+2);CHKERRQ(ierr);
626   ierr       = PetscMPIIntCast(dd->ze-dd->zs,lsizes+3);CHKERRQ(ierr);
627   lstarts[0] = 0;
628   ierr       = PetscMPIIntCast(dd->xs/dof,lstarts+1);CHKERRQ(ierr);
629   ierr       = PetscMPIIntCast(dd->ys,lstarts+2);CHKERRQ(ierr);
630   ierr       = PetscMPIIntCast(dd->zs,lstarts+3);CHKERRQ(ierr);
631   ierr       = MPI_Type_create_subarray(da->dim+1,gsizes,lsizes,lstarts,MPI_ORDER_FORTRAN,MPIU_SCALAR,&view);CHKERRQ(ierr);
632   ierr       = MPI_Type_commit(&view);CHKERRQ(ierr);
633 
634   ierr = PetscViewerBinaryGetMPIIODescriptor(viewer,&mfdes);CHKERRQ(ierr);
635   ierr = PetscViewerBinaryGetMPIIOOffset(viewer,&off);CHKERRQ(ierr);
636   ierr = MPI_File_set_view(mfdes,off,MPIU_SCALAR,view,(char*)"native",MPI_INFO_NULL);CHKERRQ(ierr);
637   ierr = VecGetArrayRead(xin,&array);CHKERRQ(ierr);
638   asiz = lsizes[1]*(lsizes[2] > 0 ? lsizes[2] : 1)*(lsizes[3] > 0 ? lsizes[3] : 1)*dof;
639   if (write) {
640     ierr = MPIU_File_write_all(mfdes,(PetscScalar*)array,asiz,MPIU_SCALAR,MPI_STATUS_IGNORE);CHKERRQ(ierr);
641   } else {
642     ierr = MPIU_File_read_all(mfdes,(PetscScalar*)array,asiz,MPIU_SCALAR,MPI_STATUS_IGNORE);CHKERRQ(ierr);
643   }
644   ierr = MPI_Type_get_extent(view,&ul,&ub);CHKERRQ(ierr);
645   ierr = PetscViewerBinaryAddMPIIOOffset(viewer,ub);CHKERRQ(ierr);
646   ierr = VecRestoreArrayRead(xin,&array);CHKERRQ(ierr);
647   ierr = MPI_Type_free(&view);CHKERRQ(ierr);
648   PetscFunctionReturn(0);
649 }
650 #endif
651 
652 PetscErrorCode  VecView_MPI_DA(Vec xin,PetscViewer viewer)
653 {
654   DM                da;
655   PetscErrorCode    ierr;
656   PetscInt          dim;
657   Vec               natural;
658   PetscBool         isdraw,isvtk,isglvis;
659 #if defined(PETSC_HAVE_HDF5)
660   PetscBool         ishdf5;
661 #endif
662   const char        *prefix,*name;
663   PetscViewerFormat format;
664 
665   PetscFunctionBegin;
666   ierr = VecGetDM(xin,&da);CHKERRQ(ierr);
667   if (!da) SETERRQ(PetscObjectComm((PetscObject)xin),PETSC_ERR_ARG_WRONG,"Vector not generated from a DMDA");
668   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
669   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERVTK,&isvtk);CHKERRQ(ierr);
670 #if defined(PETSC_HAVE_HDF5)
671   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERHDF5,&ishdf5);CHKERRQ(ierr);
672 #endif
673   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERGLVIS,&isglvis);CHKERRQ(ierr);
674   if (isdraw) {
675     ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr);
676     if (dim == 1) {
677       ierr = VecView_MPI_Draw_DA1d(xin,viewer);CHKERRQ(ierr);
678     } else if (dim == 2) {
679       ierr = VecView_MPI_Draw_DA2d(xin,viewer);CHKERRQ(ierr);
680     } else SETERRQ1(PetscObjectComm((PetscObject)da),PETSC_ERR_SUP,"Cannot graphically view vector associated with this dimensional DMDA %D",dim);
681   } else if (isvtk) {           /* Duplicate the Vec */
682     Vec Y;
683     ierr = VecDuplicate(xin,&Y);CHKERRQ(ierr);
684     if (((PetscObject)xin)->name) {
685       /* If xin was named, copy the name over to Y. The duplicate names are safe because nobody else will ever see Y. */
686       ierr = PetscObjectSetName((PetscObject)Y,((PetscObject)xin)->name);CHKERRQ(ierr);
687     }
688     ierr = VecCopy(xin,Y);CHKERRQ(ierr);
689     ierr = PetscViewerVTKAddField(viewer,(PetscObject)da,DMDAVTKWriteAll,PETSC_VTK_POINT_FIELD,(PetscObject)Y);CHKERRQ(ierr);
690 #if defined(PETSC_HAVE_HDF5)
691   } else if (ishdf5) {
692     ierr = VecView_MPI_HDF5_DA(xin,viewer);CHKERRQ(ierr);
693 #endif
694   } else if (isglvis) {
695     ierr = PetscObjectReference((PetscObject)xin);CHKERRQ(ierr);
696     ierr = VecView_GLVis(xin,viewer);CHKERRQ(ierr);
697   } else {
698 #if defined(PETSC_HAVE_MPIIO)
699     PetscBool isbinary,isMPIIO;
700 
701     ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
702     if (isbinary) {
703       ierr = PetscViewerBinaryGetUseMPIIO(viewer,&isMPIIO);CHKERRQ(ierr);
704       if (isMPIIO) {
705         ierr = DMDAArrayMPIIO(da,viewer,xin,PETSC_TRUE);CHKERRQ(ierr);
706         PetscFunctionReturn(0);
707       }
708     }
709 #endif
710 
711     /* call viewer on natural ordering */
712     ierr = PetscObjectGetOptionsPrefix((PetscObject)xin,&prefix);CHKERRQ(ierr);
713     ierr = DMDACreateNaturalVector(da,&natural);CHKERRQ(ierr);
714     ierr = PetscObjectSetOptionsPrefix((PetscObject)natural,prefix);CHKERRQ(ierr);
715     ierr = DMDAGlobalToNaturalBegin(da,xin,INSERT_VALUES,natural);CHKERRQ(ierr);
716     ierr = DMDAGlobalToNaturalEnd(da,xin,INSERT_VALUES,natural);CHKERRQ(ierr);
717     ierr = PetscObjectGetName((PetscObject)xin,&name);CHKERRQ(ierr);
718     ierr = PetscObjectSetName((PetscObject)natural,name);CHKERRQ(ierr);
719 
720     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
721     if (format == PETSC_VIEWER_BINARY_MATLAB) {
722       /* temporarily remove viewer format so it won't trigger in the VecView() */
723       ierr = PetscViewerPushFormat(viewer,PETSC_VIEWER_DEFAULT);CHKERRQ(ierr);
724     }
725 
726     ((PetscObject)natural)->donotPetscObjectPrintClassNamePrefixType = PETSC_TRUE;
727     ierr = VecView(natural,viewer);CHKERRQ(ierr);
728     ((PetscObject)natural)->donotPetscObjectPrintClassNamePrefixType = PETSC_FALSE;
729 
730     if (format == PETSC_VIEWER_BINARY_MATLAB) {
731       MPI_Comm    comm;
732       FILE        *info;
733       const char  *fieldname;
734       char        fieldbuf[256];
735       PetscInt    dim,ni,nj,nk,pi,pj,pk,dof,n;
736 
737       /* set the viewer format back into the viewer */
738       ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
739       ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
740       ierr = PetscViewerBinaryGetInfoPointer(viewer,&info);CHKERRQ(ierr);
741       ierr = DMDAGetInfo(da,&dim,&ni,&nj,&nk,&pi,&pj,&pk,&dof,0,0,0,0,0);CHKERRQ(ierr);
742       ierr = PetscFPrintf(comm,info,"#--- begin code written by PetscViewerBinary for MATLAB format ---#\n");CHKERRQ(ierr);
743       ierr = PetscFPrintf(comm,info,"#$$ tmp = PetscBinaryRead(fd); \n");CHKERRQ(ierr);
744       if (dim == 1) { ierr = PetscFPrintf(comm,info,"#$$ tmp = reshape(tmp,%d,%d);\n",dof,ni);CHKERRQ(ierr); }
745       if (dim == 2) { ierr = PetscFPrintf(comm,info,"#$$ tmp = reshape(tmp,%d,%d,%d);\n",dof,ni,nj);CHKERRQ(ierr); }
746       if (dim == 3) { ierr = PetscFPrintf(comm,info,"#$$ tmp = reshape(tmp,%d,%d,%d,%d);\n",dof,ni,nj,nk);CHKERRQ(ierr); }
747 
748       for (n=0; n<dof; n++) {
749         ierr = DMDAGetFieldName(da,n,&fieldname);CHKERRQ(ierr);
750         if (!fieldname || !fieldname[0]) {
751           ierr = PetscSNPrintf(fieldbuf,sizeof fieldbuf,"field%D",n);CHKERRQ(ierr);
752           fieldname = fieldbuf;
753         }
754         if (dim == 1) { ierr = PetscFPrintf(comm,info,"#$$ Set.%s.%s = squeeze(tmp(%d,:))';\n",name,fieldname,n+1);CHKERRQ(ierr); }
755         if (dim == 2) { ierr = PetscFPrintf(comm,info,"#$$ Set.%s.%s = squeeze(tmp(%d,:,:))';\n",name,fieldname,n+1);CHKERRQ(ierr); }
756         if (dim == 3) { ierr = PetscFPrintf(comm,info,"#$$ Set.%s.%s = permute(squeeze(tmp(%d,:,:,:)),[2 1 3]);\n",name,fieldname,n+1);CHKERRQ(ierr);}
757       }
758       ierr = PetscFPrintf(comm,info,"#$$ clear tmp; \n");CHKERRQ(ierr);
759       ierr = PetscFPrintf(comm,info,"#--- end code written by PetscViewerBinary for MATLAB format ---#\n\n");CHKERRQ(ierr);
760     }
761 
762     ierr = VecDestroy(&natural);CHKERRQ(ierr);
763   }
764   PetscFunctionReturn(0);
765 }
766 
767 #if defined(PETSC_HAVE_HDF5)
768 PetscErrorCode VecLoad_HDF5_DA(Vec xin, PetscViewer viewer)
769 {
770   DM             da;
771   PetscErrorCode ierr;
772   hsize_t        dim,rdim;
773   hsize_t        dims[6]={0},count[6]={0},offset[6]={0};
774   PetscInt       dimension,timestep,dofInd;
775   PetscScalar    *x;
776   const char     *vecname;
777   hid_t          filespace; /* file dataspace identifier */
778   hid_t          plist_id;  /* property list identifier */
779   hid_t          dset_id;   /* dataset identifier */
780   hid_t          memspace;  /* memory dataspace identifier */
781   hid_t          file_id,group;
782   hid_t          scalartype; /* scalar type (H5T_NATIVE_FLOAT or H5T_NATIVE_DOUBLE) */
783   DM_DA          *dd;
784   PetscBool      dim2 = PETSC_FALSE;
785 
786   PetscFunctionBegin;
787 #if defined(PETSC_USE_REAL_SINGLE)
788   scalartype = H5T_NATIVE_FLOAT;
789 #elif defined(PETSC_USE_REAL___FLOAT128)
790 #error "HDF5 output with 128 bit floats not supported."
791 #elif defined(PETSC_USE_REAL___FP16)
792 #error "HDF5 output with 16 bit floats not supported."
793 #else
794   scalartype = H5T_NATIVE_DOUBLE;
795 #endif
796 
797   ierr = PetscViewerHDF5OpenGroup(viewer, &file_id, &group);CHKERRQ(ierr);
798   ierr = PetscViewerHDF5GetTimestep(viewer, &timestep);CHKERRQ(ierr);
799   ierr = PetscObjectGetName((PetscObject)xin,&vecname);CHKERRQ(ierr);
800   ierr = VecGetDM(xin,&da);CHKERRQ(ierr);
801   dd   = (DM_DA*)da->data;
802   ierr = DMGetDimension(da, &dimension);CHKERRQ(ierr);
803 
804   /* Open dataset */
805 #if (H5_VERS_MAJOR * 10000 + H5_VERS_MINOR * 100 + H5_VERS_RELEASE >= 10800)
806   PetscStackCallHDF5Return(dset_id,H5Dopen2,(group, vecname, H5P_DEFAULT));
807 #else
808   PetscStackCallHDF5Return(dset_id,H5Dopen,(group, vecname));
809 #endif
810 
811   /* Retrieve the dataspace for the dataset */
812   PetscStackCallHDF5Return(filespace,H5Dget_space,(dset_id));
813   PetscStackCallHDF5Return(rdim,H5Sget_simple_extent_dims,(filespace, dims, NULL));
814 
815   /* Expected dimension for holding the dof's */
816 #if defined(PETSC_USE_COMPLEX)
817   dofInd = rdim-2;
818 #else
819   dofInd = rdim-1;
820 #endif
821 
822   /* The expected number of dimensions, assuming basedimension2 = false */
823   dim = dimension;
824   if (dd->w > 1) ++dim;
825   if (timestep >= 0) ++dim;
826 #if defined(PETSC_USE_COMPLEX)
827   ++dim;
828 #endif
829 
830   /* In this case the input dataset have one extra, unexpected dimension. */
831   if (rdim == dim+1) {
832     /* In this case the block size unity */
833     if (dd->w == 1 && dims[dofInd] == 1) dim2 = PETSC_TRUE;
834 
835     /* Special error message for the case where dof does not match the input file */
836     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);
837 
838   /* Other cases where rdim != dim cannot be handled currently */
839   } 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);
840 
841   /* Set up the hyperslab size */
842   dim = 0;
843   if (timestep >= 0) {
844     offset[dim] = timestep;
845     count[dim] = 1;
846     ++dim;
847   }
848   if (dimension == 3) {
849     ierr = PetscHDF5IntCast(dd->zs,offset + dim);CHKERRQ(ierr);
850     ierr = PetscHDF5IntCast(dd->ze - dd->zs,count + dim);CHKERRQ(ierr);
851     ++dim;
852   }
853   if (dimension > 1) {
854     ierr = PetscHDF5IntCast(dd->ys,offset + dim);CHKERRQ(ierr);
855     ierr = PetscHDF5IntCast(dd->ye - dd->ys,count + dim);CHKERRQ(ierr);
856     ++dim;
857   }
858   ierr = PetscHDF5IntCast(dd->xs/dd->w,offset + dim);CHKERRQ(ierr);
859   ierr = PetscHDF5IntCast((dd->xe - dd->xs)/dd->w,count + dim);CHKERRQ(ierr);
860   ++dim;
861   if (dd->w > 1 || dim2) {
862     offset[dim] = 0;
863     ierr = PetscHDF5IntCast(dd->w,count + dim);CHKERRQ(ierr);
864     ++dim;
865   }
866 #if defined(PETSC_USE_COMPLEX)
867   offset[dim] = 0;
868   count[dim] = 2;
869   ++dim;
870 #endif
871 
872   /* Create the memory and filespace */
873   PetscStackCallHDF5Return(memspace,H5Screate_simple,(dim, count, NULL));
874   PetscStackCallHDF5(H5Sselect_hyperslab,(filespace, H5S_SELECT_SET, offset, NULL, count, NULL));
875 
876   /* Create property list for collective dataset write */
877   PetscStackCallHDF5Return(plist_id,H5Pcreate,(H5P_DATASET_XFER));
878 #if defined(PETSC_HAVE_H5PSET_FAPL_MPIO)
879   PetscStackCallHDF5(H5Pset_dxpl_mpio,(plist_id, H5FD_MPIO_COLLECTIVE));
880 #endif
881   /* To read dataset independently use H5Pset_dxpl_mpio(plist_id, H5FD_MPIO_INDEPENDENT) */
882 
883   ierr   = VecGetArray(xin, &x);CHKERRQ(ierr);
884   PetscStackCallHDF5(H5Dread,(dset_id, scalartype, memspace, filespace, plist_id, x));
885   ierr   = VecRestoreArray(xin, &x);CHKERRQ(ierr);
886 
887   /* Close/release resources */
888   if (group != file_id) {
889     PetscStackCallHDF5(H5Gclose,(group));
890   }
891   PetscStackCallHDF5(H5Pclose,(plist_id));
892   PetscStackCallHDF5(H5Sclose,(filespace));
893   PetscStackCallHDF5(H5Sclose,(memspace));
894   PetscStackCallHDF5(H5Dclose,(dset_id));
895   PetscFunctionReturn(0);
896 }
897 #endif
898 
899 PetscErrorCode VecLoad_Binary_DA(Vec xin, PetscViewer viewer)
900 {
901   DM             da;
902   PetscErrorCode ierr;
903   Vec            natural;
904   const char     *prefix;
905   PetscInt       bs;
906   PetscBool      flag;
907   DM_DA          *dd;
908 #if defined(PETSC_HAVE_MPIIO)
909   PetscBool isMPIIO;
910 #endif
911 
912   PetscFunctionBegin;
913   ierr = VecGetDM(xin,&da);CHKERRQ(ierr);
914   dd   = (DM_DA*)da->data;
915 #if defined(PETSC_HAVE_MPIIO)
916   ierr = PetscViewerBinaryGetUseMPIIO(viewer,&isMPIIO);CHKERRQ(ierr);
917   if (isMPIIO) {
918     ierr = DMDAArrayMPIIO(da,viewer,xin,PETSC_FALSE);CHKERRQ(ierr);
919     PetscFunctionReturn(0);
920   }
921 #endif
922 
923   ierr = PetscObjectGetOptionsPrefix((PetscObject)xin,&prefix);CHKERRQ(ierr);
924   ierr = DMDACreateNaturalVector(da,&natural);CHKERRQ(ierr);
925   ierr = PetscObjectSetName((PetscObject)natural,((PetscObject)xin)->name);CHKERRQ(ierr);
926   ierr = PetscObjectSetOptionsPrefix((PetscObject)natural,prefix);CHKERRQ(ierr);
927   ierr = VecLoad(natural,viewer);CHKERRQ(ierr);
928   ierr = DMDANaturalToGlobalBegin(da,natural,INSERT_VALUES,xin);CHKERRQ(ierr);
929   ierr = DMDANaturalToGlobalEnd(da,natural,INSERT_VALUES,xin);CHKERRQ(ierr);
930   ierr = VecDestroy(&natural);CHKERRQ(ierr);
931   ierr = PetscInfo(xin,"Loading vector from natural ordering into DMDA\n");CHKERRQ(ierr);
932   ierr = PetscOptionsGetInt(NULL,((PetscObject)xin)->prefix,"-vecload_block_size",&bs,&flag);CHKERRQ(ierr);
933   if (flag && bs != dd->w) {
934     ierr = PetscInfo2(xin,"Block size in file %D not equal to DMDA's dof %D\n",bs,dd->w);CHKERRQ(ierr);
935   }
936   PetscFunctionReturn(0);
937 }
938 
939 PetscErrorCode  VecLoad_Default_DA(Vec xin, PetscViewer viewer)
940 {
941   PetscErrorCode ierr;
942   DM             da;
943   PetscBool      isbinary;
944 #if defined(PETSC_HAVE_HDF5)
945   PetscBool ishdf5;
946 #endif
947 
948   PetscFunctionBegin;
949   ierr = VecGetDM(xin,&da);CHKERRQ(ierr);
950   if (!da) SETERRQ(PetscObjectComm((PetscObject)xin),PETSC_ERR_ARG_WRONG,"Vector not generated from a DMDA");
951 
952 #if defined(PETSC_HAVE_HDF5)
953   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERHDF5,&ishdf5);CHKERRQ(ierr);
954 #endif
955   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
956 
957   if (isbinary) {
958     ierr = VecLoad_Binary_DA(xin,viewer);CHKERRQ(ierr);
959 #if defined(PETSC_HAVE_HDF5)
960   } else if (ishdf5) {
961     ierr = VecLoad_HDF5_DA(xin,viewer);CHKERRQ(ierr);
962 #endif
963   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Viewer type %s not supported for vector loading", ((PetscObject)viewer)->type_name);
964   PetscFunctionReturn(0);
965 }
966