xref: /petsc/src/dm/tests/ex2.c (revision 732aec7a18f2199fb53bb9a2f3aef439a834ce31)

static char help[] = "Tests various 1-dimensional DMDA routines.\n\n";

#include <petscdm.h>
#include <petscdmda.h>
#include <petscdraw.h>

int main(int argc, char **argv)
{
  PetscMPIInt            rank;
  PetscInt               M = 13, s = 1, dof = 1, n;
  DMBoundaryType         bx = DM_BOUNDARY_PERIODIC;
  DM                     da;
  PetscViewer            viewer;
  Vec                    local, global;
  PetscScalar            value, *array;
  PetscDraw              draw;
  PetscBool              flg = PETSC_FALSE;
  ISLocalToGlobalMapping is;

  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &argv, NULL, help));
  PetscCall(PetscViewerDrawOpen(PETSC_COMM_WORLD, 0, "", 280, 480, 600, 200, &viewer));
  PetscCall(PetscViewerDrawGetDraw(viewer, 0, &draw));
  PetscCall(PetscDrawSetDoubleBuffer(draw));

  /* Readoptions */
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-M", &M, NULL));
  PetscCall(PetscOptionsGetEnum(NULL, NULL, "-wrap", DMBoundaryTypes, (PetscEnum *)&bx, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-dof", &dof, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-s", &s, NULL));

  /* Create distributed array and get vectors */
  PetscCall(DMDACreate1d(PETSC_COMM_WORLD, bx, M, dof, s, NULL, &da));
  PetscCall(DMSetFromOptions(da));
  PetscCall(DMSetUp(da));
  PetscCall(DMView(da, viewer));
  PetscCall(DMCreateGlobalVector(da, &global));
  PetscCall(DMCreateLocalVector(da, &local));

  value = 1;
  PetscCall(VecSet(global, value));

  PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
  value = rank + 1;
  PetscCall(VecGetLocalSize(global, &n));
  PetscCall(VecGetArray(global, &array));
  for (PetscInt i = 0; i < n; i++) array[i] *= value;
  PetscCall(VecRestoreArray(global, &array));

  PetscCall(VecView(global, viewer));
  PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "\nGlobal Vector:\n"));
  PetscCall(VecView(global, PETSC_VIEWER_STDOUT_WORLD));
  PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "\n"));

  /* Send ghost points to local vectors */
  PetscCall(DMGlobalToLocalBegin(da, global, INSERT_VALUES, local));
  PetscCall(DMGlobalToLocalEnd(da, global, INSERT_VALUES, local));

  PetscCall(PetscOptionsGetBool(NULL, NULL, "-local_print", &flg, NULL));
  if (flg) {
    PetscViewer sviewer;

    PetscCall(PetscViewerASCIIPushSynchronized(PETSC_VIEWER_STDOUT_WORLD));
    PetscCall(PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
    PetscCall(PetscViewerASCIIPrintf(sviewer, "\nLocal Vector: processor %d\n", rank));
    PetscCall(VecView(local, sviewer));
    PetscCall(PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
    PetscCall(PetscViewerASCIIPopSynchronized(PETSC_VIEWER_STDOUT_WORLD));
  }
  PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "\nLocal to global mapping\n"));
  PetscCall(DMGetLocalToGlobalMapping(da, &is));
  PetscCall(ISLocalToGlobalMappingView(is, PETSC_VIEWER_STDOUT_WORLD));

  /* Free memory */
  PetscCall(PetscViewerDestroy(&viewer));
  PetscCall(VecDestroy(&global));
  PetscCall(VecDestroy(&local));
  PetscCall(DMDestroy(&da));
  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

   test:
      nsize: 2
      args: -nox
      filter: grep -v " MPI process"
      output_file: output/ex2_1.out
      requires: x

   test:
      suffix: 2
      nsize: 3
      args: -wrap none -local_print -nox
      filter: grep -v "Vec Object: Vec"
      requires: x

   test:
      suffix: 3
      nsize: 3
      args: -wrap ghosted -local_print -nox
      filter: grep -v "Vec Object: Vec"
      requires: x

TEST*/