anchor.diff:          do i = 1, size(parent_population)
               if (.not.(abs(parent_population(i)) > initiator_pop .or. determ_flag == 0)) then
                   ! Isn't an initiator.
  -                parent_flag = ibset(parent_flag, i)
  +                parent_flag = ibset(parent_flag, i - 1)
               ! Otherwise has a high enough population to be an initiator in this space,
               ! or is a deterministic state (which must always be an initiator).
               end if
  
positive.code: 
          parent_flag = 0_int_p
          do i = 1, size(parent_population), 2
              if (.not.((sqrt(parent_population(i) ** 2 + parent_population(i+1) ** 2) > initiator_pop) .or.&
                      (determ_flag == 0))) then
                  ! Isn't an initiator.
                  parent_flag = ibset(parent_flag, i)
                  parent_flag = ibset(parent_flag, i + 1)
              end if
              ! Otherwise has a high enough population to be an initiator in this space,
              ! or is a deterministic state (which must always be an initiator).
  
negative.code:         ! Out:
          !    parent_flag: set to 0 if the determinant is an initiator and 1 otherwise.
  
          use const, only: p
  
          real(p), intent(in) :: parent_population(:), initiator_pop
          integer, intent(in) :: determ_flag
          integer, intent(out) :: parent_flag
  