[gradsusr] Opening a file having overlapping longitude points.

[Pou-Chang John Chen]

I'm not sure about the format, but you may try to open via OPeNDAP 
server. http://dapper.pmel.noaa.gov/dapper/oscar/
For example, 
'sdfopen http://dapper.pmel.noaa.gov/dapper/oscar/world-filter-longterm.nc'
I have tried this. It should work.

I hope this help you
John
 
________________________________
GrADS Tutorial on Facebook
http://www.wishingwork.com/grads/




________________________________
From: Martin V. Mathew <vmartinmathew at gmail.com>
To: gradsusr at gradsusr.org
Sent: Tue, March 29, 2011 2:22:16 PM
Subject: [gradsusr] Opening a file having overlapping longitude points.

Hai All

I have a problem in opening an ocean current data in NetCDF format, downloaded 
from URL
http://www.oscar.noaa.gov/datadisplay/index.html

It is a 1degree resolution file with 400 longitude points. 
It is given in the documentation of the data that

'Longitude extends from 20.5 E to 419.5 E to avoid a break in major ocean 
basins. 

Data repeats in overlap region.'

Dimensions of the data is as  follows

*****************************************************************************************

        time = 12 ;
        depth = 1 ;
        lat = 120 ;
        lon = 400 ;

 lat = 59.5, 58.5, 57.5, 56.5,.................................
    
.................................................................................,
 -57.5, -58.5, -59.5 ;

 lon = 20.5, 21.5, 22.5, 23.5,..................... 
    ..............., 357.5,358.5, 359.5, 360.5, 361.5, 362.5, 363.5, 364.5, 
    365.5, 366.5, 367.5, 368.5, 369.5, 370.5, 371.5, 372.5, 373.5, 374.5,
    375.5, 376.5, 377.5, 378.5, 379.5, 380.5, 381.5, 382.5, 383.5, 384.5,
    385.5, 386.5, 387.5, 388.5, 389.5, 390.5, 391.5, 392.5, 393.5, 394.5,
    395.5, 396.5, 397.5, 398.5, 399.5, 400.5, 401.5, 402.5, 403.5, 404.5,
    405.5, 406.5, 407.5, 408.5, 409.5, 410.5, 411.5, 412.5, 413.5, 414.5, 
    415.5, 416.5, 417.5, 418.5, 419.5 ;
*****************************************************************************************


While trying to open the file in GrADS using sdfopen following error message is 
displayed
------------------------------------------------------------------------------------

Scanning self-describing file:  oscar-4cff2332a2540_1995.nc
gadsdf: SDF file has no discernable X coordinate.
------------------------------------------------------------------------------------


I also tried to open the file using a control file in which I defined longitude 
as follows

  DSET oscar-4cff2332a2540_1995.nc
    XDEF lon 400 LEVELS  20.5, 21.5, 22.5, 23.5, .........................
    
..........................................................................................................................

    .............., 355.5, 356.5, 357.5, 358.5, 359.5,.5,1.5,2.5, 
3.5,............
    
.....................................................................,55.5,56.5,57.5,58.5,59.5



I couldn't open the file using this method also.
While trying to open the file  following error message is displayed

------------------------------------------------------------------------------------

ga-> xdfopen oscar-4cff2332a2540_1995.ctl
Scanning Descriptor File:  oscar-4cff2332a2540_1995.ctl
Open Error:  Unexpected EOF reading descriptor file
   EOF occurred reading LEVELS values
  --> The invalid description file record is: 
  -->     46.5,47.5,48.5,49.5,50.5,51.5,52.5,53.5,54.5,55.5,56.5,57.5,58.5,59.5

  The data file was not opened.
ga->
------------------------------------------------------------------------------------


Somebody please give me a suggestion to solve this problem.

Thanking you

Martin V. Mathew
J.R.F.
Centre for Oceans, Rivers, Atmosphere and Land Sciences (CORAL)
IIT Kharagpur
India.


      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20110329/59324e58/attachment-0003.html