Re: odd ut_calendar behavior

Hi all,

We haven't been ignoring this issue. We created a trouble ticket for it (NCL-904 for your reference)
and will hopefully get this fixed by the next release.

Our plan for the next release is a 6.0.0-beta sometime in January. There are *lots* of issues
with the ut_xxxx functions that may be unresolvable, due to the fact that the underlying UDUNITS2
library no longer supports the calendaring functions.

--Mary

On Dec 13, 2010, at 4:17 PM, Dave Allured wrote:

> Never mind about the old version. I get the same incorrect value
> that you did with NCL 5.2.1 on Mac OS 10.6.
>
> mac56:~ 1> ncl
> NCAR Command Language Version 5.2.1
> ncl 0> x = 364.5d
> ncl 1> x@units = "days since 2005-01-01 12:00:00"
> ncl 2> x@calendar = "noleap"
> ncl 3> print (""+ut_calendar(x,-3))
> (0) 2005123124
>
> --Dave
>
> On 12/13/2010 3:45 PM, Dave Allured wrote:
>> Rich,
>>
>> Okay, this confirms what you expected in the first place, the output
>> from print(ut_calendar(inptr->time, -3)) should be 2006010100. The
>> final "24" (hours) should never be seen. The function should always
>> carry up to the next day, so that hours is always 00 to 23.
>>
>> This looks like a roundoff problem in the ut_calendar function or
>> calendar support routines. There was a previous bug report on a
>> problem like this in the UDUNITS support library, but I think that
>> was fixed years ago. Are you using a very old version of NCL?
>> Beyond that, I should say no more and let NCL support staff take a
>> closer look.
>>
>> --Dave
>>
>> On 12/13/2010 2:35 PM, Rich Neale wrote:
>>> Here it is Dave, thanks!
>>>
>>> Variable: time
>>> Type: double
>>> Total Size: 8 bytes
>>> 1 values
>>> Number of Dimensions: 1
>>> Dimensions and sizes: [time | 1]
>>> Coordinates:
>>> time: [364.5..364.5]
>>> Number Of Attributes: 4
>>> long_name : time
>>> units : days since 2005-01-01 12:00:00
>>> calendar : noleap
>>> bounds : time_bnds
>>> (0) 364.5
>>>
>>>
>>> On 12/13/2010 02:33 PM, Dave Allured wrote:
>>>> Rich,
>>>>
>>>> To simplify diagnosis, please show the full output from this command:
>>>>
>>>> print(inptr->time)
>>>>
>>>> --Dave
>>>>
>>>> On 12/13/2010 2:06 PM, Rich Neale wrote:
>>>>> Hi, I am getting strange behavior from ut_calendar when I run the
>>>>> following on cgd systems for those interested). I am trying to
>>>>> test that
>>>>> the date of a CAM file is January 2006.
>>>>>
>>>>> inptr =
>>>>> addfile("/project/convection/juliob/CAMruns/twdLL05/twdLL05.cam2.h1.2006-01-01-00000.nc","r")
>>>>>
>>>>> print(ut_calendar(inptr->time, -3))
>>>>>
>>>>> *Result
>>>>>
>>>>> Variable: unnamed (return)
>>>>> Type: integer
>>>>> Total Size: 4 bytes
>>>>> 1 values
>>>>> Number of Dimensions: 1
>>>>> Dimensions and sizes: [1]
>>>>> Coordinates:
>>>>> Number Of Attributes: 1
>>>>> calendar : noleap
>>>>> (0) 2005123124
>>>>>
>>>>>
>>>>>
>>>>> I would expect this to be 2006010100
>>>>> Any idea why this is 24 at the end and not 00?
>>>>> Below is an ncdump -h on the file.
>>>>> The time units are a little odd
>>>>> time:units = "days since 2005-01-01 12:00:00" ;
>>>>>
>>>>> And I am wondering if ut_calendar is having difficulty with the '12'
>>>>>
>>>>> Thanks!!
>>>>> Rich
>>>>>
>>>>> *********************************************
>>>>>
>>>>> netcdf twdLL05.cam2.h1.2006-01-01-00000 {
>>>>> dimensions:
>>>>> lat = 96 ;
>>>>> lon = 144 ;
>>>>> slat = 95 ;
>>>>> slon = 144 ;
>>>>> lev = 30 ;
>>>>> ilev = 31 ;
>>>>> isccp_prs = 7 ;
>>>>> isccp_tau = 7 ;
>>>>> isccp_prstau = 49 ;
>>>>> time = UNLIMITED ; // (1 currently)
>>>>> tbnd = 2 ;
>>>>> chars = 8 ;
>>>>> variables:
>>>>> double P0 ;
>>>>> P0:long_name = "reference pressure" ;
>>>>> P0:units = "Pa" ;
>>>>> double lat(lat) ;
>>>>> lat:long_name = "latitude" ;
>>>>> lat:units = "degrees_north" ;
>>>>> double lon(lon) ;
>>>>> lon:long_name = "longitude" ;
>>>>> lon:units = "degrees_east" ;
>>>>> double slat(slat) ;
>>>>> slat:long_name = "staggered latitude" ;
>>>>> slat:units = "degrees_north" ;
>>>>> double slon(slon) ;
>>>>> slon:long_name = "staggered longitude" ;
>>>>> slon:units = "degrees_east" ;
>>>>> double w_stag(slat) ;
>>>>> w_stag:long_name = "staggered latitude weights" ;
>>>>> double lev(lev) ;
>>>>> lev:long_name = "hybrid level at midpoints (1000*(A+B))" ;
>>>>> lev:units = "level" ;
>>>>> lev:positive = "down" ;
>>>>> lev:standard_name =
>>>>> "atmosphere_hybrid_sigma_pressure_coordinate" ;
>>>>> lev:formula_terms = "a: hyam b: hybm p0: P0 ps: PS" ;
>>>>> double ilev(ilev) ;
>>>>> ilev:long_name = "hybrid level at interfaces
>>>>> (1000*(A+B))" ;
>>>>> ilev:units = "level" ;
>>>>> ilev:positive = "down" ;
>>>>> ilev:standard_name =
>>>>> "atmosphere_hybrid_sigma_pressure_coordinate" ;
>>>>> ilev:formula_terms = "a: hyai b: hybi p0: P0 ps: PS" ;
>>>>> double isccp_prs(isccp_prs) ;
>>>>> isccp_prs:long_name = "Mean ISCCP pressure" ;
>>>>> isccp_prs:units = "mb" ;
>>>>> isccp_prs:isccp_prs_bnds = 0., 180., 310., 440., 560.,
>>>>> 680., 800., 1000. ;
>>>>> double isccp_tau(isccp_tau) ;
>>>>> isccp_tau:long_name = "Mean ISCCP optical depth" ;
>>>>> isccp_tau:units = "unitless" ;
>>>>> isccp_tau:isccp_tau_bnds = 0., 0.3, 1.3, 3.6, 9.4, 23.,
>>>>> 60., 379. ;
>>>>> double isccp_prstau(isccp_prstau) ;
>>>>> isccp_prstau:long_name = "Mean pressure (mb).mean
>>>>> optical depth (unitless)/1000" ;
>>>>> isccp_prstau:units = "mixed" ;
>>>>> double time(time) ;
>>>>> time:long_name = "time" ;
>>>>> time:units = "days since 2005-01-01 12:00:00" ;
>>>>> time:calendar = "noleap" ;
>>>>> time:bounds = "time_bnds" ;
>>>>> double time_bnds(time, tbnd) ;
>>>>> time_bnds:long_name = "time interval endpoints" ;
>>>>> char date_written(time, chars) ;
>>>>> char time_written(time, chars) ;
>>>>> int ntrm ;
>>>>> ntrm:long_name = "spectral truncation parameter M" ;
>>>>> int ntrn ;
>>>>> ntrn:long_name = "spectral truncation parameter N" ;
>>>>> int ntrk ;
>>>>> ntrk:long_name = "spectral truncation parameter K" ;
>>>>> int ndbase ;
>>>>> ndbase:long_name = "base day" ;
>>>>> int nsbase ;
>>>>> nsbase:long_name = "seconds of base day" ;
>>>>> int nbdate ;
>>>>> nbdate:long_name = "base date (YYYYMMDD)" ;
>>>>> int nbsec ;
>>>>> nbsec:long_name = "seconds of base date" ;
>>>>> int mdt ;
>>>>> mdt:long_name = "timestep" ;
>>>>> mdt:units = "s" ;
>>>>> int nlon(lat) ;
>>>>> nlon:long_name = "number of longitudes" ;
>>>>> int wnummax(lat) ;
>>>>> wnummax:long_name = "cutoff Fourier wavenumber" ;
>>>>> double hyai(ilev) ;
>>>>> hyai:long_name = "hybrid A coefficient at layer
>>>>> interfaces" ;
>>>>> double hybi(ilev) ;
>>>>> hybi:long_name = "hybrid B coefficient at layer
>>>>> interfaces" ;
>>>>> double hyam(lev) ;
>>>>> hyam:long_name = "hybrid A coefficient at layer
>>>>> midpoints" ;
>>>>> double hybm(lev) ;
>>>>> hybm:long_name = "hybrid B coefficient at layer
>>>>> midpoints" ;
>>>>> double gw(lat) ;
>>>>> gw:long_name = "gauss weights" ;
>>>>> int ndcur(time) ;
>>>>> ndcur:long_name = "current day (from base day)" ;
>>>>> int nscur(time) ;
>>>>> nscur:long_name = "current seconds of current day" ;
>>>>> int date(time) ;
>>>>> date:long_name = "current date (YYYYMMDD)" ;
>>>>> double co2vmr(time) ;
>>>>> co2vmr:long_name = "co2 volume mixing ratio" ;
>>>>> double ch4vmr(time) ;
>>>>> ch4vmr:long_name = "ch4 volume mixing ratio" ;
>>>>> double n2ovmr(time) ;
>>>>> n2ovmr:long_name = "n2o volume mixing ratio" ;
>>>>> double f11vmr(time) ;
>>>>> f11vmr:long_name = "f11 volume mixing ratio" ;
>>>>> double f12vmr(time) ;
>>>>> f12vmr:long_name = "f12 volume mixing ratio" ;
>>>>> double sol_tsi(time) ;
>>>>> sol_tsi:long_name = "total solar irradiance" ;
>>>>> sol_tsi:units = "W/m2" ;
>>>>> int datesec(time) ;
>>>>> datesec:long_name = "current seconds of current date" ;
>>>>> int nsteph(time) ;
>>>>> nsteph:long_name = "current timestep" ;
>>>>> float OMEGA(time, lev, lat, lon) ;
>>>>> OMEGA:units = "Pa/s" ;
>>>>> OMEGA:long_name = "Vertical velocity (pressure)" ;
>>>>> float PBLH(time, lat, lon) ;
>>>>> PBLH:units = "m" ;
>>>>> PBLH:long_name = "PBL height" ;
>>>>> float PRECC(time, lat, lon) ;
>>>>> PRECC:units = "m/s" ;
>>>>> PRECC:long_name = "Convective precipitation rate (liq +
>>>>> ice)" ;
>>>>> float PRECL(time, lat, lon) ;
>>>>> PRECL:units = "m/s" ;
>>>>> PRECL:long_name = "Large-scale (stable) precipitation
>>>>> rate (liq + ice)" ;
>>>>> float PRECSH(time, lat, lon) ;
>>>>> PRECSH:units = "m/s" ;
>>>>> PRECSH:long_name = "Shallow Convection precipitation
>>>>> rate" ;
>>>>> float PS(time, lat, lon) ;
>>>>> PS:units = "Pa" ;
>>>>> PS:long_name = "Surface pressure" ;
>>>>> float Q(time, lev, lat, lon) ;
>>>>> Q:units = "kg/kg" ;
>>>>> Q:long_name = "Specific humidity" ;
>>>>> float T(time, lev, lat, lon) ;
>>>>> T:units = "K" ;
>>>>> T:long_name = "Temperature" ;
>>>>> float U(time, lev, lat, lon) ;
>>>>> U:units = "m/s" ;
>>>>> U:long_name = "Zonal wind" ;
>>>>> float V(time, lev, lat, lon) ;
>>>>> V:units = "m/s" ;
>>>>> V:long_name = "Meridional wind" ;
>>>>>
>>>>> // global attributes:
>>>>> :Conventions = "CF-1.0" ;
>>>>> :source = "CAM" ;
>>>>> :case = "twdLL05" ;
>>>>> :title = "atm case twdLL" ;
>>>>> :logname = "juliob" ;
>>>>> :host = "be1005en.ucar.ed" ;
>>>>> :Version = "$Name$" ;
>>>>> :revision_Id = "$Id$" ;
>>>>> :initial_file =
>>>>> "/fs/cgd/csm/inputdata/atm/cam/inic/fv/cami-mam3_0000-01-01_1.9x2.5_L30_c090306.nc"
>>>>>
>>>>> ;
>>>>> :topography_file =
>>>>> "/fs/cgd/csm/inputdata/atm/cam/topo/USGS-gtopo30_1.9x2.5_remap_c050602.nc"
>>>>> ;
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Received on Wed Dec 22 16:08:29 2010