anchor.diff:    type(xsData),         allocatable, target :: xsdatas(:)
     type(StructuredMesh), allocatable, target :: meshes(:)
     type(TallyObject),    allocatable, target :: tallies(:)
  -  type(TallyObject),    allocatable, target :: tallies_global(:)
   
     ! Size of main arrays
     integer :: n_cells          ! # of cells
  
positive.code:   real(8) :: keff
    real(8) :: keff_std
  
    logical :: tallies_on
  
    ! Parallel processing variables
  
negative.code:   integer :: n_materials      ! # of materials
    integer :: n_meshes         ! # of structured meshes
    integer :: n_tallies        ! # of tallies
  
    ! These dictionaries provide a fast lookup mechanism -- the key is the
    ! user-specified identifier and the value is the index in the corresponding
  