anchor.diff:      real(dp),intent(in) :: length_limit             ! minimum length of a generated branch (shorter == terminal)
       real(dp),intent(in) :: shortest_length          ! length that short branches are reset to (shortest in model)
       real(dp),intent(in) :: rotation_limit           ! maximum angle of rotation of branching plane
  -    logical,intent(in) :: to_export                 ! option to export terminal element mapping to datapoints
  -    character(len=*),intent(in) :: filename
  +!    logical,intent(in) :: to_export                 ! option to export terminal element mapping to datapoints
  +!    character(len=*),intent(in) :: filename
   
       !Local variables
       integer,allocatable :: local_parent(:)          ! stores current generation of local parent elements
  
positive.code: 
      enddo ! for each initial parent
  
      if(to_export)then
        close(40)
      endif
  
  !!! set new total numbers of nodes and elements
      num_nodes=np !highest node # in nr
  
negative.code:   !*grow_tree:* the main growing subroutine (public). Genertes a volume-filling
    ! tree into a closed surface.
    !
    subroutine grow_tree(surface_elems,parent_ne,angle_max,angle_min,&
         branch_fraction,length_limit,shortest_length,rotation_limit)
      !DEC$ ATTRIBUTES DLLEXPORT,ALIAS:"SO_GROW_TREE" :: GROW_TREE
  
      integer,intent(in)  :: parent_ne                ! list of end branch elements to grow from
  