anchor.diff:       >             real(k)*dr,gr(k)
          end do
          stop
  -
  -911    continue       
  +411    continue
  +1000   format(
  +     > "NAME:",/
  +     > " rdf constructs radial density function ",
  +     > " from NWChem trajectory or xyz files",//,
  +     >  "SYNOPSIS",/,
  +     > " rdf [-help] [-v ]",
  +     > " [-frames ] [-lattice ] [-nbins ] [-rmax] [-atom1] [-atom2]",
  +     > " input file(s) outpiut file ",//,
  +     >  "DESCRIPTION",/,
  +     > " This utility builds rdf from NWChem trajectory",
  +     > " or xyz files",//,
  +     > " The required option are as follows:",/,
  +     > " -atom1   first atom id or name",/,
  +     > " -atom2   second atom id or name",/,
  +     > " -lattice lattice file or vector(3)",/,
  +     > " -rmax    maximum distance ",//,
  +     > " other options are as follows:",/,
  +     > " -help  prints out this message",/,
  +     > " -v  generate more verbose output",/,
  +     > " -frames  maximum number of frames default is all ",/,
  +     > " -nbins number of bins with default of rmax/0.1"
  +     > )
  + 911    continue       
   c      if you reach this you are in trouble
          write(*,*) "Emergency STOP"
          write(*,*) message
  
positive.code:        end if
  c      maximum radius
         if(rmax.lt.0) then
           rmax = 0.5*MINVAL(latv)
         end if
  c      number of bins
         if(nb.lt.0) then
  
negative.code:        else if(buffer.eq."-v") then
            overb=.true.
            go to 16
         else if(buffer.eq."-help") then
            ohelp=.true.
            write(*,1000)
            stop
         else if(buffer.eq."-atom1") then
            i = i+1
            call my_get_command_argument(i,buffer,l,istatus)
  