[gradsusr] Missing variables in 3-d fwrite binary file

James T. Potemra jimp at hawaii.edu
Fri Jul 22 12:48:54 EDT 2011


Hi Kevin:

It looks like in your NAM-2011072200.ctl file you are defining one 
vertical level:

zdef 1 levels 315

but you then assign two levels to each variable:

cpd                   2 99 Condensation Pressure Deficit (mb)
isenps                2 99 Pressure (mb)
u                     2 99 Zonal component of wind (ms^-1)
v                     2 99 Meridional component of wind (ms^-1)

I think if you change the "2's" above with "1", or for surface you can 
have "0",
it should work ok.

Jim

On 7/22/11 2:49 AM, Kevin Huyck wrote:
> Good morning.
>
> I'm attempting to configure some post-processing subroutines for 
> several parameters I find useful. For my pathfinder case, I am 
> creating a binary file using "fwrite" to store four parameters. Each 
> parameter varies in the horizontal plane, but not in the vertical 
> (i.e. only one vertical level is computed). When I output a single 
> timestep, I can open and retrieve the data file and the data display 
> correctly. If I write each variable twice, once for each time step, I 
> can retrieve the first time step, but not the second. At present I'm 
> feeding commands into the command-line interpreter rather than 
> executing a script. I've seen examples in the archives discussing 
> varying the time dimension by way of a "while" loop. Since I'm 
> entering the commands individually the result /should/ be the same as 
> if run from a script.
>
> I'm not sure where I'm making my mistake in the process, so any 
> guidance would be appreciated.
>
> Input data is the North American Mesoscale (NAM) 40 km model. I am 
> computing values for "t 1" and "t 2" during this trial period.  The 
> variables utilized in the process are "cpd", "isenps", "u", and "v". 
> Command sequence is first, followed by the .ctl file. I use a homemade 
> script file, "compute_cpd.gs", to conduct the necessary calculations. 
> This script accepts three arguments, Theta surface (in Kelvin), grid 
> skip, and working file number. compute_cpd.gs returns cpd, isenps, u, 
> and v. In this case, "z" in NAM-2011072200.dat represents the "theta" 
> level for the isentropic surface.
>
> --- Command Listing ---
> open NAM-2011072200.ctl
> set t 1
> run compute_cpd.gs 315 1 1
>
> set fwrite ./cpd/NAM-2011072200.dat
> set gxout fwrite
>
> d cpd
> d isenps
> d u
> d v
>
> set t 2
> run compute_cpd.gs 315 1 1
>
> d cpd
> d isenps
> d u
> d v
>
> disable fwrite
> reinit
>
> open ./cpd/NAM-2011072200.ctl
> set t 1
> run ./draw-cpd.gs
>
> clear graphics
> set t 2
> run ./draw-cpd.gs
>
> --- Error Output ---
> Low Level I/O Error:  Read error on data file
>   Data file name = ./cpd/NAM-2011072200.dat
>   Error reading 200 bytes at location 704000
> Data Request Error:  Error for variable 'cpd'
>   Error ocurred at column 1
> DISPLAY error:  Invalid expression
>   Expression = cpd
> Cannot plot color bar: No shading information
> Low Level I/O Error:  Read error on data file
>   Data file name = ./cpd/NAM-2011072200.dat
>   Error reading 200 bytes at location 704000
> Data Request Error:  Error for variable 'cpd'
>   Error ocurred at column 1
> DISPLAY error:  Invalid expression
>   Expression = cpd
> Low Level I/O Error:  Read error on data file
>   Data file name = ./cpd/NAM-2011072200.dat
>   Error reading 200 bytes at location 880000
> Data Request Error:  Error for variable 'isenps'
>   Error ocurred at column 1
> DISPLAY error:  Invalid expression
>   Expression = isenps
> Low Level I/O Error:  Read error on data file
>   Data file name = ./cpd/NAM-2011072200.dat
>   Error reading 200 bytes at location 1056000
> Data Request Error:  Error for variable 'u'
> Operation Error:  Error from skip function
>   Error ocurred at column 1
> DISPLAY error:  Invalid expression
>   Expression = skip(u,2)
>
> --- ./cpd/NAM-2011072200.ctl Contents ---
> dset /home/Agena/klhuyck/cpd/NAM-2011072200.dat
> title NAM 40km Condensation Pressure Deficit
> undef -999000000.000000
> options little_endian
> xdef 200 linear -145.0 0.5
> ydef 110 linear 12.0 0.5
> zdef 1 levels 315
> tdef 2 linear 00Z22Jul2011 3hr
> vars 4
> cpd                   2 99 Condensation Pressure Deficit (mb)
> isenps                2 99 Pressure (mb)
> u                     2 99 Zonal component of wind (ms^-1)
> v                     2 99 Meridional component of wind (ms^-1)
> endvars
>
> -- 
> Kevin L. Huyck
> Forecaster, Meridian Environmental Technology, Inc.
> klhuyck at meridian-enviro.com <mailto:klhuyck at meridian-enviro.com>
>
> Composed using Mozilla Thunderbird!
>
>
> _______________________________________________
> gradsusr mailing list
> gradsusr at gradsusr.org
> http://gradsusr.org/mailman/listinfo/gradsusr
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20110722/4de890bf/attachment-0003.html 


More information about the gradsusr mailing list