xref: /petsc/src/sys/tests/ex50.c (revision c4762a1b19cd2af06abeed90e8f9d34fb975dd94)
1 
2 static char help[] = "Tests using PetscViewerGetSubViewer() recursively\n\n";
3 
4 /*T
5    Concepts: viewers
6    Processors: n
7 T*/
8 #include <petscsys.h>
9 #include <petscviewer.h>
10 
11 
12 int main(int argc,char **argv)
13 {
14   PetscErrorCode    ierr;
15   PetscViewer       viewer,subviewer,subsubviewer;
16   PetscViewerFormat format;
17   PetscBool         flg;
18   PetscSubcomm      psubcomm,psubsubcomm;
19   MPI_Comm          comm,subcomm,subsubcomm;
20   PetscMPIInt       size;
21 
22   /*
23     Every PETSc routine should begin with the PetscInitialize() routine.
24     argc, argv - These command line arguments are taken to extract the options
25                  supplied to PETSc and options supplied to MPI.
26     help       - When PETSc executable is invoked with the option -help,
27                  it prints the various options that can be applied at
28                  runtime.  The user can use the "help" variable place
29                  additional help messages in this printout.
30   */
31   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
32   comm = PETSC_COMM_WORLD;
33   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
34   if (size < 4) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP,"Must run with at least 4 MPI processes");
35   ierr = PetscOptionsGetViewer(comm,NULL,NULL,"-viewer",&viewer,&format,&flg);CHKERRQ(ierr);
36   if (!viewer) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP,"Must use -viewer option");
37 
38   ierr = PetscViewerASCIIPrintf(viewer,"Print called on original full viewer %d\n",PetscGlobalRank);CHKERRQ(ierr);
39 
40   ierr = PetscSubcommCreate(comm,&psubcomm);CHKERRQ(ierr);
41   ierr = PetscSubcommSetNumber(psubcomm,2);CHKERRQ(ierr);
42   ierr = PetscSubcommSetType(psubcomm,PETSC_SUBCOMM_CONTIGUOUS);CHKERRQ(ierr);
43   /* enable runtime switch of psubcomm type, e.g., '-psubcomm_type interlaced */
44   ierr = PetscSubcommSetFromOptions(psubcomm);CHKERRQ(ierr);
45   subcomm = PetscSubcommChild(psubcomm);
46 
47   ierr = PetscViewerGetSubViewer(viewer,subcomm,&subviewer);CHKERRQ(ierr);
48 
49   ierr = PetscViewerASCIIPrintf(subviewer,"  Print called on sub viewers %d\n",PetscGlobalRank);CHKERRQ(ierr);
50 
51   ierr = PetscSubcommCreate(subcomm,&psubsubcomm);CHKERRQ(ierr);
52   ierr = PetscSubcommSetNumber(psubsubcomm,2);CHKERRQ(ierr);
53   ierr = PetscSubcommSetType(psubsubcomm,PETSC_SUBCOMM_CONTIGUOUS);CHKERRQ(ierr);
54   /* enable runtime switch of psubcomm type, e.g., '-psubcomm_type interlaced */
55   ierr = PetscSubcommSetFromOptions(psubsubcomm);CHKERRQ(ierr);
56   subsubcomm = PetscSubcommChild(psubsubcomm);
57 
58   ierr = PetscViewerGetSubViewer(subviewer,subsubcomm,&subsubviewer);CHKERRQ(ierr);
59 
60   ierr = PetscViewerASCIIPrintf(subsubviewer,"  Print called on sub sub viewers %d\n",PetscGlobalRank);CHKERRQ(ierr);
61 
62   ierr = PetscViewerRestoreSubViewer(subviewer,subsubcomm,&subsubviewer);CHKERRQ(ierr);
63   ierr = PetscViewerRestoreSubViewer(viewer,subcomm,&subviewer);CHKERRQ(ierr);
64 
65   ierr = PetscSubcommDestroy(&psubsubcomm);CHKERRQ(ierr);
66   ierr = PetscSubcommDestroy(&psubcomm);CHKERRQ(ierr);
67   ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
68   ierr = PetscFinalize();
69   return ierr;
70 }
71 
72 
73 /*TEST
74 
75    test:
76       nsize: 4
77       args: -viewer
78 
79 TEST*/
80