load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"

begin
;=================================================;
; open file and read in data
;=================================================;
  f    = addfile("/home/saeed/lorestan/input/lorestan_DOMAIN000.nc","r")
  t  = f->topo    ; You don't need the "(:,:)" to get the whole array.

  wks  = gsn_open_wks("ps","gsn_contour")

  res                     = True
  res@cnFillOn            = True         ; turn on color
  res@cnLineLabelsOn      = False        ; no contour line labels

  plot = gsn_csm_contour_map(wks,t,res)          ; contour the variable
end