Re: Time Units

Thank you very much
It works.
I just amazed , I know that when we read grib or netcdf file ,Usually, we
need to convert the Julian date to UT date, as the Julian date is big
number that we cannot sense it. But in my case we are doing the opposite
thing just so as to NCL understood the date.
Thanks

On Mon, Feb 11, 2013 at 4:11 PM, Kyle Griffin <ksgriffin2@wisc.edu> wrote:

> Hi Ahmed,
>
> You'll have to turn these dates into a date format understood by NCL. In
> this case, you can use cd_inv_calendar to do the job.
>
> timeUnits = "days since 1-1-1 00:00:00"
> time = cd_inv_calendar(years,months,days,00,00,00.0,timeUnits,0)
>
> When doing this, cd_inv_calendar will assign the @units itself. The choice
> of units in my code is arbitrary; it could be anything here as long as you
> give it to "time" for time_axis_labels to read later.
>
>
> Kyle
>
>
> ----------------------------------------
> Kyle S. Griffin
> Department of Atmospheric and Oceanic Sciences
> University of Wisconsin - Madison
> 1225 W Dayton St, Madison, WI 53706
> Email: ksgriffin2@wisc.edu
>
>
> On Mon, Feb 11, 2013 at 2:47 AM, Ahmed Lasheen <ahmed4kernel@gmail.com>wrote:
>
>> Dear All,
>>
>> I am trying to plot station data consists of two column, the
>> fist column is the data which is written in the following format (YYYYMMDD)
>> and the other column is the variable. When I use the time_axis_label , I
>> got the following error.
>>
>> function (0) time_axis_labels: The variable containing time values must
>> have a 'units' attribute.
>>
>> I wrote the following command for defining the time units , but is also
>> not true time@units="months", I know that time units is something like
>> that "hours since 1-1-1 00:00:00", but I actually have the time itself not
>> a number of hours or months. I don't know what to wrote for units.
>>
>> The following is the script
>>
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/contrib/cd_string.ncl"
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/contrib/time_axis_labels.ncl"
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
>> ;************************************************
>> begin
>> ;************************************************
>> ; plotting parameters
>> ;************************************************
>> new_rows=systemfunc("wc -l a.txt| cut -d' ' -f1")
>> days=systemfunc("cut -c1-2 a.txt")
>> months=systemfunc("cut -c3-4 a.txt")
>> years=systemfunc("cut -c5-8 a.txt")
>> var=systemfunc("cut -f2 -d' ' a.txt")
>> print(var)
>> time=years+months+days
>> print(time)
>> wks = gsn_open_wks ("x11","xy") ;
>> open workstation
>> res = True ; plot mods desired
>> res@tiMainString = "Multiple XY plot" ; add title
>> res@tiMainString = "Mulitple XY plot with markers" ; add
>> title
>> resplot = True
>> restick = True
>> restick@ttmFormat = "%Y%N%D"
>>
>> time@units="months"
>> time_axis_labels(tointeger(time),resplot,restick) ; call the formatting
>> procedure
>>
>> plot = gsn_csm_xy (wks,time,tointger(var),res) ; create plot
>> end
>>
>>
>>
>> I have attached the script and the data file.
>> Thanks in advance
>> --
>> ===============
>> Ahmed Lasheen
>> Junior researcher at Cairo Numerical Weather Prediction Center (CNWPC)
>> Egyptian Meteorological Authority(EMA)
>> Cairo,Egypt
>> ===============
>>
>> _______________________________________________
>> ncl-talk mailing list
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>
>>
>

-- 
===============
Ahmed Lasheen
Junior researcher at Cairo Numerical Weather Prediction Center (CNWPC)
Egyptian Meteorological Authority(EMA)
Cairo,Egypt
===============

_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Tue Feb 12 08:36:14 2013