anchor.diff:                          ! actually produces the correct truncated space without
                           ! requiring this test...
                           in_space = .true.
  -                        if (all(ras > 0)) then
  -                            call encode_det(sys%basis, occ, f)
  -                            in_space = in_ras(ras1, ras3, ras1_min, ras3_max, f)
  -                        else if (truncate_space) then
  +                        if (truncate_space) then
                               call encode_det(sys%basis, occ, f)
                               in_space = get_excitation_level(d0%f,f) <= truncation_level
                           end if
  
positive.code:             call encode_det(sys%basis, occ_list0, d0%f)
              ! Check symmetries of reference matches the desired symmetries.  If
              ! not, are doing spin flip and need to do a full enumeration!
              if (spin_flip .or. all(ras > 0)) then
                  force_full = .true.
              else
                  call decode_det_spinocc_spinunocc(sys, d0%f, d0)
  
negative.code:         use utils, only: binom_i, get_free_unit, int_fmt
          use bit_utils, only: first_perm, bit_permutation, decode_bit_string, count_set_bits
  
          use calc, only: truncate_space, truncation_level
          use excitations, only: get_excitation_level
          use system
          use symmetry, only: cross_product, symmetry_orb_list
          use ueg_system, only: ueg_basis_index
  