xref: /petsc/src/dm/tutorials/ex10.c (revision c4762a1b19cd2af06abeed90e8f9d34fb975dd94)
1*c4762a1bSJed Brown /*
2*c4762a1bSJed Brown    Demonstrates using the HDF5 viewer with a DMDA Vec
3*c4762a1bSJed Brown  - create a global vector containing a gauss profile (exp(-x^2-y^2))
4*c4762a1bSJed Brown  - write the global vector in a hdf5 file
5*c4762a1bSJed Brown 
6*c4762a1bSJed Brown    The resulting file gauss.h5 can be viewed with Visit (an open source visualization package)
7*c4762a1bSJed Brown    Or with some versions of MATLAB with data=hdfread('gauss.h5','pressure'); mesh(data);
8*c4762a1bSJed Brown 
9*c4762a1bSJed Brown    The file storage of the vector is independent of the number of processes used.
10*c4762a1bSJed Brown  */
11*c4762a1bSJed Brown 
12*c4762a1bSJed Brown #include <petscdm.h>
13*c4762a1bSJed Brown #include <petscdmda.h>
14*c4762a1bSJed Brown #include <petscsys.h>
15*c4762a1bSJed Brown #include <petscviewerhdf5.h>
16*c4762a1bSJed Brown 
17*c4762a1bSJed Brown static char help[] = "Test to write HDF5 file from PETSc DMDA Vec.\n\n";
18*c4762a1bSJed Brown 
19*c4762a1bSJed Brown int main(int argc,char **argv)
20*c4762a1bSJed Brown {
21*c4762a1bSJed Brown   PetscErrorCode ierr;
22*c4762a1bSJed Brown   DM             da2D;
23*c4762a1bSJed Brown   PetscInt       i,j,ixs, ixm, iys, iym;
24*c4762a1bSJed Brown   PetscViewer    H5viewer;
25*c4762a1bSJed Brown   PetscScalar    xm    = -1.0, xp=1.0;
26*c4762a1bSJed Brown   PetscScalar    ym    = -1.0, yp=1.0;
27*c4762a1bSJed Brown   PetscScalar    value = 1.0,dx,dy;
28*c4762a1bSJed Brown   PetscInt       Nx    = 40, Ny=40;
29*c4762a1bSJed Brown   Vec            gauss,input;
30*c4762a1bSJed Brown   PetscScalar    **gauss_ptr;
31*c4762a1bSJed Brown   PetscReal      norm;
32*c4762a1bSJed Brown   const char     *vecname;
33*c4762a1bSJed Brown 
34*c4762a1bSJed Brown   dx=(xp-xm)/(Nx-1);
35*c4762a1bSJed Brown   dy=(yp-ym)/(Ny-1);
36*c4762a1bSJed Brown 
37*c4762a1bSJed Brown   /* Initialize the Petsc context */
38*c4762a1bSJed Brown   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
39*c4762a1bSJed Brown   ierr = DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE,DMDA_STENCIL_STAR,Nx,Ny,PETSC_DECIDE,PETSC_DECIDE,1,1,NULL,NULL,&da2D);CHKERRQ(ierr);
40*c4762a1bSJed Brown   ierr = DMSetFromOptions(da2D);CHKERRQ(ierr);
41*c4762a1bSJed Brown   ierr = DMSetUp(da2D);CHKERRQ(ierr);
42*c4762a1bSJed Brown 
43*c4762a1bSJed Brown   /* Set the coordinates */
44*c4762a1bSJed Brown   ierr = DMDASetUniformCoordinates(da2D, 0.0, 1.0, 0.0, 1.0, 0.0, 0.0);CHKERRQ(ierr);
45*c4762a1bSJed Brown 
46*c4762a1bSJed Brown   /* Declare gauss as a DMDA component */
47*c4762a1bSJed Brown   ierr = DMCreateGlobalVector(da2D,&gauss);CHKERRQ(ierr);
48*c4762a1bSJed Brown   ierr = PetscObjectSetName((PetscObject) gauss, "pressure");CHKERRQ(ierr);
49*c4762a1bSJed Brown 
50*c4762a1bSJed Brown   /* Initialize vector gauss with a constant value (=1) */
51*c4762a1bSJed Brown   ierr = VecSet(gauss,value);CHKERRQ(ierr);
52*c4762a1bSJed Brown 
53*c4762a1bSJed Brown   /* Get the coordinates of the corners for each process */
54*c4762a1bSJed Brown   ierr = DMDAGetCorners(da2D, &ixs, &iys, 0, &ixm, &iym, 0);CHKERRQ(ierr);
55*c4762a1bSJed Brown 
56*c4762a1bSJed Brown   /* Build the gaussian profile (exp(-x^2-y^2)) */
57*c4762a1bSJed Brown   ierr = DMDAVecGetArray(da2D,gauss,&gauss_ptr);CHKERRQ(ierr);
58*c4762a1bSJed Brown   for (j=iys; j<iys+iym; j++) {
59*c4762a1bSJed Brown     for (i=ixs; i<ixs+ixm; i++) {
60*c4762a1bSJed Brown       gauss_ptr[j][i]=PetscExpScalar(-(xm+i*dx)*(xm+i*dx)-(ym+j*dy)*(ym+j*dy));
61*c4762a1bSJed Brown     }
62*c4762a1bSJed Brown   }
63*c4762a1bSJed Brown   ierr = DMDAVecRestoreArray(da2D,gauss,&gauss_ptr);CHKERRQ(ierr);
64*c4762a1bSJed Brown 
65*c4762a1bSJed Brown   /* Create the HDF5 viewer */
66*c4762a1bSJed Brown   ierr = PetscViewerHDF5Open(PETSC_COMM_WORLD,"gauss.h5",FILE_MODE_WRITE,&H5viewer);CHKERRQ(ierr);
67*c4762a1bSJed Brown   ierr = PetscViewerSetFromOptions(H5viewer);CHKERRQ(ierr);
68*c4762a1bSJed Brown 
69*c4762a1bSJed Brown   /* Write the H5 file */
70*c4762a1bSJed Brown   ierr = VecView(gauss,H5viewer);CHKERRQ(ierr);
71*c4762a1bSJed Brown 
72*c4762a1bSJed Brown   /* Close the viewer */
73*c4762a1bSJed Brown   ierr = PetscViewerDestroy(&H5viewer);CHKERRQ(ierr);
74*c4762a1bSJed Brown 
75*c4762a1bSJed Brown   ierr = VecDuplicate(gauss,&input);CHKERRQ(ierr);
76*c4762a1bSJed Brown   ierr = PetscObjectGetName((PetscObject)gauss,&vecname);CHKERRQ(ierr);
77*c4762a1bSJed Brown   ierr = PetscObjectSetName((PetscObject)input,vecname);CHKERRQ(ierr);
78*c4762a1bSJed Brown 
79*c4762a1bSJed Brown   /* Create the HDF5 viewer for reading */
80*c4762a1bSJed Brown   ierr = PetscViewerHDF5Open(PETSC_COMM_WORLD,"gauss.h5",FILE_MODE_READ,&H5viewer);CHKERRQ(ierr);
81*c4762a1bSJed Brown   ierr = PetscViewerSetFromOptions(H5viewer);CHKERRQ(ierr);
82*c4762a1bSJed Brown   ierr = VecLoad(input,H5viewer);CHKERRQ(ierr);
83*c4762a1bSJed Brown   ierr = PetscViewerDestroy(&H5viewer);CHKERRQ(ierr);
84*c4762a1bSJed Brown 
85*c4762a1bSJed Brown   ierr = VecAXPY(input,-1.0,gauss);CHKERRQ(ierr);
86*c4762a1bSJed Brown   ierr = VecNorm(input,NORM_2,&norm);CHKERRQ(ierr);
87*c4762a1bSJed Brown   if (norm > 1.e-6) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Vec read in does not match vector written out");
88*c4762a1bSJed Brown 
89*c4762a1bSJed Brown   ierr = VecDestroy(&input);CHKERRQ(ierr);
90*c4762a1bSJed Brown   ierr = VecDestroy(&gauss);CHKERRQ(ierr);
91*c4762a1bSJed Brown   ierr = DMDestroy(&da2D);CHKERRQ(ierr);
92*c4762a1bSJed Brown   ierr = PetscFinalize();
93*c4762a1bSJed Brown   return ierr;
94*c4762a1bSJed Brown }
95*c4762a1bSJed Brown 
96*c4762a1bSJed Brown 
97*c4762a1bSJed Brown /*TEST
98*c4762a1bSJed Brown 
99*c4762a1bSJed Brown       build:
100*c4762a1bSJed Brown          requires: hdf5 !define(PETSC_USE_CXXCOMPLEX)
101*c4762a1bSJed Brown 
102*c4762a1bSJed Brown       test:
103*c4762a1bSJed Brown          nsize: 4
104*c4762a1bSJed Brown 
105*c4762a1bSJed Brown       test:
106*c4762a1bSJed Brown          nsize: 4
107*c4762a1bSJed Brown          suffix: 2
108*c4762a1bSJed Brown          args: -viewer_hdf5_base_dimension2
109*c4762a1bSJed Brown          output_file: output/ex10_1.out
110*c4762a1bSJed Brown 
111*c4762a1bSJed Brown       test:
112*c4762a1bSJed Brown          nsize: 4
113*c4762a1bSJed Brown          suffix: 3
114*c4762a1bSJed Brown          args: -viewer_hdf5_sp_output
115*c4762a1bSJed Brown          output_file: output/ex10_1.out
116*c4762a1bSJed Brown 
117*c4762a1bSJed Brown TEST*/
118