anchor.diff:  
       ! If true then, if doing an exact diagonalisation, calculate and output the
       ! eigenvalues of the reduced density matrix requested.
  -    logical :: doing_exact_rdm_eigv=.false.
  +    logical :: doing_exact_rdm_eigv = .false.
   
       ! If true then the reduced density matrix is output to a file, 'reduced_dm'
       ! each beta loop.
  
positive.code:     type(hash_table_t) :: ht
  end type rdm_spawn_t
  
  ! [todo] - move to dmqmc_state_t
  ! This type contains information for the RDM corresponding to a given
  ! subsystem. It takes translational symmetry into account by storing information
  ! for all subsystems which are equivalent by translational symmetry.
  
negative.code: 
  end type dmqmc_rdm_in_t
  
  ! Spawned lists for rdms.
  type rdm_spawn_t
      type(spawn_t) :: spawn
  