grads xdfopen netcdf file with template option

[Diane Stokes]

Youhua,

Set xdef, ydef, zdef and tdef as you would in a regular ctl file.
Remove COL, ROW, LAY and TSTEP from your def statements.

Don't forget to change your variable statement too.  Maybe:

SO2=>so2 21 x,y,z,t  SO2 (ppbv)

Check the output of your "ncdump -c" to get the order right for your
dimensions.  See:

http://grads.iges.org/grads/gadoc/descriptorfile.html#VARS

specifically, units for DTYPE netcdf or hdfsds.


     Diane




Youhua Tang wrote:

> Thank you for your information, Diane. I tried your method. However, my
> netcdf file is a non-COARDS-compliant file. Do you know how to convert
> coordinate name using "open"? For example, the x-coordinate in my netcdf
> file is "COL", and I can use "xdef COL 97 linear 1. 1." with "xdfopen",
> but how I can make it work using "open".
>
>
> Youhua
>
> On Wed, 5 Jan 2005, Diane Stokes wrote:
>
>
>>Dear Youhua,
>>
>>The new "dtype netcdf" in 1.9b3 has done the trick for me for netcdf
>>files with multiple time steps.  See:
>>
>>http://grads.iges.org/grads/gadoc/descriptorfile.html#DTYPE
>>
>>You'd then use "open" rather than "xdfopen".
>>
>>     Good Luck.
>>       Diane
>>
>>
>>Youhua Tang wrote:
>>
>>
>>>Hello, All:
>>>
>>>I found that current version of grads do not well handle
>>>the netcdf file with template option. When I use xdfopen to open
>>>the ddf file as below
>>>
>>>dset ^SOUT.%m2-%d2-00.nc
>>>title 3D gaseous species
>>>undef  -99999.0
>>>options template
>>>xdef COL 97 linear 1. 1.
>>>ydef ROW 62 linear 1. 1.
>>>zdef LAY 21 levels 7.25 25.40 54.5117 109.328 219.887 406.969 675.054
>>>990.77 135
>>>8.73 1828.5 2368.88 2942.16 3553.04 4207.36 4912.52 5678.06 6516.63
>>>7527.75 8868
>>>.97 10717.2 13153.4
>>>* in GMT
>>>tdef TSTEP 377 linear 00Z01JUL2004 3hr
>>>vars 1
>>>SO2=>so2 21 99 SO2 (ppbv)
>>>endvars
>>>
>>>The grads-1.8s111 has "Segmentation fault" (my linux machine uses
>>>RedHat 7.3). The grads-1.9beta3 is "slightly" better as it can finish
>>>'xdfopen', but "Segmentation fault" appeared again when I perform further
>>>operation, like 'd ave(so2,t=1,t=300)'. I found that only
>>>grads-1.7beta9 can handle all the issues, but this old version lacks of
>>>some useful math functions. Does anybody know how to
>>>solve this problem?
>>>
>>>Thanks a lot
>>>
>>>
>>>Youhua Tang
>>>
>>

--
Diane Stokes
Environmental Modeling Center
National Weather Service/NOAA