read_species_config Subroutine

  subroutine read_species_config(self)
    use file_utils, only: input_unit_exist, get_indexed_namelist_unit
    use mp, only: proc0
    implicit none
    class(species_config_type), intent(in out) :: self
    logical :: exist
    integer :: in_file

    ! Note: When this routine is in the module where these variables live
    ! we shadow the module level variables here. This is intentional to provide
    ! isolation and ensure we can move this routine to another module easily.    
    integer :: nspec
    real :: me, zi_fac

    namelist /species_knobs/ me, nspec, zi_fac

    ! Only proc0 reads from file
    if (.not. proc0) return

    ! First set local variables from current values
    me = self%me
    nspec = self%nspec
    zi_fac = self%zi_fac

    ! Now read in the main namelist
    in_file = input_unit_exist(self%get_name(), exist)
    if (exist) read(in_file, nml = species_knobs)

    ! Now copy from local variables into type members
    self%me = me
    self%nspec = nspec
    self%zi_fac = zi_fac

    self%exist = exist
  end subroutine read_species_config