anchor.diff:  
     ! check that, in case R1/R2 are declared by the user in terms of n-sigma, the provided info is consistent
     do j=1,nelens
  -    if (elens_r1(j).lt.zero .or. elens_r2(j).lt.zero .or. elens_sig(j).lt.zero) then
  +    if (elens_r1(j)<zero .or. elens_r2(j)<zero .or. elens_sig(j)<zero) then
         ! printout:
         ! - find name of elens
         do jj=1,nele
  
positive.code:     end if
      
      if(st_debug) then
        call sixin_echoVal("fox",tmplFox,"ELENS",iLine)
      end if
       
    case("INTER")
      if(nSplit.lt.2 .or. nSplit.gt.3) then
        write(lerr,"(a,i0)") "ELENS> ERROR Expected 1 or 2 input parameters for INTERpolation line, got ",nSplit-1
        write(lerr,"(a)")    "ELENS>       example:     INTER  <elens_radial_mpoints> (ALL|BEF(ORE)|AFT(ER))"
        iErr = .true.
  
negative.code:   real(kind=fPrec), intent(in) :: bDisp(2)
    real(kind=fPrec), intent(in) :: bDispP(2)
  
    if(iElem<1 .or. iElem>nele .or. ( elens_r1(ielens(iElem))>zero .and. &
         elens_r2(ielens(iElem))>zero .and. elens_sig(ielens(iElem))>zero)) return
  
    elens_nUpdates(ielens(iElem))=elens_nUpdates(ielens(iElem))+1
  
    if (elens_emin(ielens(iElem))>zero) then ! betatron cut
      select case (elens_iSet(ielens(iElem)))
      case(1) ! min
         if (elens_optVal(ielens(iElem)).eq.zero) then ! first time
  