A self-defined function time2calendar can be written in a single NCL script and it can be called by another script.

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"
function time2calendar(time_in) 
begin
   month_abbr = (/"","Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep", \
                       "Oct","Nov","Dec"/)
    time = time_in
    time@units = time_in@units
    utc_date = cd_calendar(time, 0) ;convert to UTC
    year = tointeger(utc_date(:,0))
    month = tointeger(utc_date(:,1))
    day = tointeger(utc_date(:,2))
    hour = tointeger(utc_date(:,3))
    minute = tointeger(utc_date(:,4))
    date_str = sprinti("%0.2iZ ", hour) + sprinti("%0.2i ", day) + \
    month_abbr(month) + " " + sprinti("%0.4i", year)
    return(date_str)
end

In a script, we can call this function as follows

load "time2calendar.ncl"  
begin
...
date=time2calendar(u_obs&time)
print(date1)
...
end

See it is a very good way to perform objectification in NCL!

Last update: 09/26/2020