NCL批量读入4个文件后，怎么只输出一个文件的计算结果

爽歪歪

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

begin

diri = "/home/liluck/ncl/data/"
fils = systemfunc ("ls "+diri+"*.grib")
f= addfiles (fils, "r")
;print(f)

ListSetType (f, "cat")
  hgt=f[:]->HGT_3_ISBL({500},{35:60},{115:145})

  dims = dimsizes(hgt)
  x1d = ndtooned(hgt)      ; convert 2D array to 1D for use in minind
  inds = ind_resolve(minind (x1d), dims)    ; convert 1D array back to 2D
  ilat = inds(0,0)        
  ilon = inds(0,1)        
  lat_min = hgt&lat_3(ilat)   
  lon_min = hgt&lon_3(ilon)  
  print("Minimum value located at "+lat_min+", "+lon_min)
end