xref: /petsc/src/dm/tutorials/ex9.c (revision a69119a591a03a9d906b29c0a4e9802e4d7c9795)
1 static char help[] = "Demonstrates HDF5 vector input/ouput\n\n";
2 
3 #include <petscsys.h>
4 #include <petscdm.h>
5 #include <petscdmda.h>
6 #include <petscviewerhdf5.h>
7 
8 int main(int argc, char **argv) {
9   PetscViewer viewer;
10   DM          da;
11   Vec         global, local, global2;
12   PetscMPIInt rank;
13   PetscBool   flg;
14   PetscInt    ndof;
15 
16   /*
17     Every PETSc routine should begin with the PetscInitialize() routine.
18     argc, argv - These command line arguments are taken to extract the options
19                  supplied to PETSc and options supplied to MPI.
20     help       - When PETSc executable is invoked with the option -help,
21                  it prints the various options that can be applied at
22                  runtime.  The user can use the "help" variable place
23                  additional help messages in this printout.
24   */
25   PetscFunctionBeginUser;
26   PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
27   /* Get number of DOF's from command line */
28   PetscOptionsBegin(PETSC_COMM_WORLD, NULL, "DMDA VecView/VecLoad example", "");
29   {
30     ndof = 1;
31     PetscOptionsBoundedInt("-ndof", "Number of DOF's in DMDA", "", ndof, &ndof, NULL, 1);
32   }
33   PetscOptionsEnd();
34 
35   /* Create a DMDA and an associated vector */
36   PetscCall(DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DMDA_STENCIL_BOX, 100, 90, PETSC_DECIDE, PETSC_DECIDE, ndof, 1, NULL, NULL, &da));
37   PetscCall(DMSetFromOptions(da));
38   PetscCall(DMSetUp(da));
39   PetscCall(DMCreateGlobalVector(da, &global));
40   PetscCall(DMCreateLocalVector(da, &local));
41   PetscCall(VecSet(global, -1.0));
42   PetscCall(DMGlobalToLocalBegin(da, global, INSERT_VALUES, local));
43   PetscCall(DMGlobalToLocalEnd(da, global, INSERT_VALUES, local));
44   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
45   PetscCall(VecScale(local, rank + 1));
46   PetscCall(DMLocalToGlobalBegin(da, local, ADD_VALUES, global));
47   PetscCall(DMLocalToGlobalEnd(da, local, ADD_VALUES, global));
48 
49   /* Create the HDF5 viewer for writing */
50   PetscCall(PetscViewerHDF5Open(PETSC_COMM_WORLD, "hdf5output.h5", FILE_MODE_WRITE, &viewer));
51   PetscCall(PetscViewerSetFromOptions(viewer));
52 
53   /* Write the Vec without one extra dimension for BS */
54   PetscCall(PetscViewerHDF5SetBaseDimension2(viewer, PETSC_FALSE));
55   PetscCall(PetscObjectSetName((PetscObject)global, "noBsDim"));
56   PetscCall(VecView(global, viewer));
57 
58   /* Write the Vec with one extra, 1-sized, dimension for BS */
59   PetscCall(PetscViewerHDF5SetBaseDimension2(viewer, PETSC_TRUE));
60   PetscCall(PetscObjectSetName((PetscObject)global, "bsDim"));
61   PetscCall(VecView(global, viewer));
62 
63   PetscCall(PetscViewerDestroy(&viewer));
64   PetscCallMPI(MPI_Barrier(PETSC_COMM_WORLD));
65   PetscCall(VecDuplicate(global, &global2));
66 
67   /* Create the HDF5 viewer for reading */
68   PetscCall(PetscViewerHDF5Open(PETSC_COMM_WORLD, "hdf5output.h5", FILE_MODE_READ, &viewer));
69   PetscCall(PetscViewerSetFromOptions(viewer));
70 
71   /* Load the Vec without the BS dim and compare */
72   PetscCall(PetscObjectSetName((PetscObject)global2, "noBsDim"));
73   PetscCall(VecLoad(global2, viewer));
74 
75   PetscCall(VecEqual(global, global2, &flg));
76   if (!flg) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Error: Vectors are not equal\n"));
77 
78   /* Load the Vec with one extra, 1-sized, BS dim and compare */
79   PetscCall(PetscObjectSetName((PetscObject)global2, "bsDim"));
80   PetscCall(VecLoad(global2, viewer));
81   PetscCall(PetscViewerDestroy(&viewer));
82 
83   PetscCall(VecEqual(global, global2, &flg));
84   if (!flg) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Error: Vectors are not equal\n"));
85 
86   /* clean up and exit */
87   PetscCall(VecDestroy(&local));
88   PetscCall(VecDestroy(&global));
89   PetscCall(VecDestroy(&global2));
90   PetscCall(DMDestroy(&da));
91 
92   PetscCall(PetscFinalize());
93   return 0;
94 }
95 
96 /*TEST
97 
98       build:
99          requires: hdf5
100 
101       test:
102          nsize: 4
103 
104       test:
105          nsize: 4
106          suffix: 2
107          args: -ndof 2
108          output_file: output/ex9_1.out
109 
110 TEST*/
111