error in ctl file

Douglas Clark dbcl at CEH.AC.UK
Wed Feb 4 04:03:17 EST 2009


It's difficult to know what the problem is unless you give more information about how you created the file!

There's potentially quite a lot of information that you need to provide, but the following at least would be useful:
* the script or commands that you used to perform the fwrite, and what GrADS output to the screen when you did this
* the ctl file you created for the output
* the results of the command "ncdump -h taux97-98.cdf" (if you have the ncdump utility)

In the meantime, is it possible that you only wrote out 1 time of the netCDF file? How big is the file tauxobs.grd (e.g. ls -l in Unix)? If the grid is of size nx*ny points, one year of monthly data should give a file of size nx*ny*12*4 bytes. If your file is smaller, you haven't written all times, so repeat the fwrite stage after 'set t 1 12' (or whatever is appropriate). Try this first!


>>> anushridutta01 at GMAIL.COM 04/02/2009 07:20 >>>
Dear Grads User,
here I am facing a problem, that i want to write a binary data for
the 12 month by data taux97-98.cdf, through fwrite function,
but when I pot the data through ctl file,
it display for a single month, not for all the months,
and the error which it showing is

ga-> open taux.ctl
Scanning description file:  taux.ctl
Data file tauxobs.grd is open as file 1
LON set to 64.5 160
LAT set to -15 10
LEV set to 1 1
Time values set: 1997:1:1:0 1997:1:1:0
ga-> set t 1
Time values set: 1997:1:1:0 1997:1:1:0
ga-> d taux
Contouring: -0.08 to 0.08 interval 0.02
ga-> set t 2
Time values set: 1997:2:1:0 1997:2:1:0
ga-> d taux
Low Level I/O Error:  Read error on data file
  Data file name = tauxobs.grd
  Error reading 192 bytes at location 313344
Data Request Error:  Error for variable 'taux'
  Error ocurred at column 1
DISPLAY error:  Invalid expression
  Expression = taux

same as for the 3 to 12 month,

I am not understanding why it is so,
Please tell me, how do I achieve this,

with regards


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