C++ (Cpp) VecMax_Seq Examples

Example #1

File: pvec2.c Project: erdc-cm/petsc-dev

EXTERN_C_END

#undef __FUNCT__
#define __FUNCT__ "VecMax_MPI"
PetscErrorCode VecMax_MPI(Vec xin,PetscInt *idx,PetscReal *z)
{
  PetscErrorCode ierr;
  PetscReal      work;

  PetscFunctionBegin;
  /* Find the local max */
  ierr = VecMax_Seq(xin,idx,&work);CHKERRQ(ierr);

  /* Find the global max */
  if (!idx) {
    ierr = MPI_Allreduce(&work,z,1,MPIU_REAL,MPIU_MAX,((PetscObject)xin)->comm);CHKERRQ(ierr);
  } else {
    PetscReal work2[2],z2[2];
    PetscInt  rstart;
    rstart = xin->map->rstart;
    work2[0] = work;
    work2[1] = *idx + rstart;
    ierr = MPI_Allreduce(work2,z2,2,MPIU_REAL,VecMax_Local_Op,((PetscObject)xin)->comm);CHKERRQ(ierr);
    *z   = z2[0];
    *idx = (PetscInt)z2[1];
  }
  PetscFunctionReturn(0);
}

Example #2

File: pvec2.c Project: tom-klotz/petsc

PetscErrorCode VecMax_MPI(Vec xin,PetscInt *idx,PetscReal *z)
{
  PetscErrorCode ierr;
  PetscReal      work;

  PetscFunctionBegin;
  /* Find the local max */
  ierr = VecMax_Seq(xin,idx,&work);CHKERRQ(ierr);

  /* Find the global max */
  if (!idx) {
    ierr = MPIU_Allreduce(&work,z,1,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)xin));CHKERRQ(ierr);
  } else {
    PetscReal work2[2],z2[2];
    PetscInt  rstart;
    rstart   = xin->map->rstart;
    work2[0] = work;
    work2[1] = *idx + rstart;
    ierr     = MPIU_Allreduce(work2,z2,2,MPIU_REAL,MPIU_MAXINDEX_OP,PetscObjectComm((PetscObject)xin));CHKERRQ(ierr);
    *z       = z2[0];
    *idx     = (PetscInt)z2[1];
  }
  PetscFunctionReturn(0);
}