set_init_fields Subroutine

  subroutine set_init_fields
    use fields_implicit, only: init_allfields_implicit
    use fields_test, only: init_phi_test
    use mp, only: proc0
    use fields_local, only: init_allfields_local
    use fields_gf_local, only: init_allfields_gf_local
    use dist_fn, only: gf_lo_integrate
    use gs2_layouts, only: gf_local_fields
    use kt_grids, only: naky, ntheta0
    implicit none
    logical, parameter :: debug=.false.
    if(proc0.and.debug) write(6,*) "Syncing fields with g."
    select case (fieldopt_switch)
    case (fieldopt_implicit)
       if (debug) write(6,*) "init_fields: init_allfields_implicit"
       call init_allfields_implicit
    case (fieldopt_test)
       if (debug) write(6,*) "init_fields: init_phi_test"
       call init_phi_test
    case (fieldopt_local)
       if (debug) write(6,*) "init_fields: init_allfields_local"
       call init_allfields_local
    case (fieldopt_gf_local)
       if (debug) write(6,*) "init_fields: init_allfields_gf_local"
       if(.not. gf_lo_integrate .or. .not. gf_local_fields) then
          if(proc0) then
             write(*,*) 'gf_lo_integrate',gf_lo_integrate,'gf_local_fields',gf_local_fields
             write(*,*) 'gf local fields cannot be used by gf_lo_integrate'
             write(*,*) 'defaulting to local fields'
             write(*,*) 'if you want to use gf local fields then set gf_lo_integrate to true in dist_fn_knobs'
             write(*,*) 'and gf_local_fields to true in layouts_knobs and make sure you are running on more MPI'
             write(*,*) 'mpi processes than naky*ntheta0.  For this simulation that is: ',naky*ntheta0
          end if
          fieldopt_switch = fieldopt_local
          call init_allfields_local
       else
          call init_allfields_gf_local
       end if
    end select
  end subroutine set_init_fields