anchor.diff:         end if
   c      output file
          file_out = infile(nfil)
  -       if(ofile) then
  -               message = "opening output file "//file_out
  -          open(fn_out,file=file_out,
  +       message = "opening output file "//file_out
  +       open(fn_out,file=file_out,
        $            form='formatted',status='unknown',err=911)
  -       else
  -           message = "cannot open output file: "//file_out
  -           goto 911
  -       end if 
   
          if(overb) then
            write(*,*) "lattice vectors"
  
positive.code:        nf = 0
         do
           if(aformat.eq."trj") then
             call trj_read(fn_in,n,c,lat,ok)
           else if(aformat.eq."xyz")  then
             call xyz_read(n,c,atag,fn_in)
             ok=n.ne.0
           end if
           if(.not.ok) exit
           oc1=.false.
  
negative.code:            lat(k,k) = latv(k)
           end do
         end if
  c      maximum radius
         if(rmax.lt.0) then
           message = "please provide rmax"
  