xref: /petsc/src/sys/tests/ex58.c (revision 609caa7c8c030312b00807b4f015fd827bb80932)

static char help[] = "Tests PetscGlobalMinMax\n\n";

#include <petscsys.h>

int main(int argc, char **argv)
{
  PetscMPIInt size, rank;
  PetscInt    li[2], gi[2] = {-1, -1};
  PetscReal   lr[2], gr[2] = {-1., -1.};

  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &argv, NULL, help));
  PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
  PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));

  li[0] = 4 + rank;
  li[1] = -3 + size - rank;
  PetscCall(PetscGlobalMinMaxInt(PETSC_COMM_WORLD, li, gi));
  if (gi[0] != 4 || gi[1] != -3 + size) PetscCall(PetscPrintf(PETSC_COMM_SELF, "1) Error MIN/MAX %" PetscInt_FMT " %" PetscInt_FMT "\n", gi[0], gi[1]));
  PetscCall(PetscGlobalMinMaxInt(PETSC_COMM_WORLD, li, li));
  if (li[0] != gi[0] || li[1] != gi[1]) PetscCall(PetscPrintf(PETSC_COMM_SELF, "2) Error MIN/MAX %" PetscInt_FMT " %" PetscInt_FMT "\n", li[0], li[1]));

  if (rank == 0) {
    li[0] = PETSC_INT_MAX;
    li[1] = PETSC_INT_MIN;
  } else if (rank == 1) {
    li[0] = PETSC_INT_MIN;
    li[1] = PETSC_INT_MAX;
  }

  PetscCall(PetscGlobalMinMaxInt(PETSC_COMM_WORLD, li, gi));
  if (gi[0] > li[0] || gi[1] < li[1]) PetscCall(PetscPrintf(PETSC_COMM_SELF, "3) Error MIN/MAX %" PetscInt_FMT " %" PetscInt_FMT "\n", gi[0], gi[1]));

  lr[0] = 4.0 + rank;
  lr[1] = -3.0 + size - rank;
  PetscCall(PetscGlobalMinMaxReal(PETSC_COMM_WORLD, lr, gr));
  if (gr[0] != 4.0 || gr[1] != -3.0 + size) PetscCall(PetscPrintf(PETSC_COMM_SELF, "4) Error MIN/MAX %g %g\n", (double)gr[0], (double)gr[1]));
  PetscCall(PetscGlobalMinMaxReal(PETSC_COMM_WORLD, lr, lr));
  if (lr[0] != gr[0] || lr[1] != gr[1]) PetscCall(PetscPrintf(PETSC_COMM_SELF, "5) Error MIN/MAX %g %g\n", (double)lr[0], (double)li[1]));

  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

   test:
     output_file: output/empty.out

   test:
     suffix: 2
     output_file: output/empty.out
     nsize: 2

TEST*/