Re: problem reading 64-bit offset NetCDF files - ncl 6.1.0-beta

From: Mary Haley <haley_at_nyahnyahspammersnyahnyah>
Date: Tue Jul 24 2012 - 08:36:17 MDT

John,

Can you try this test interactively, which I just verified works with 6.1.0-beta on several of our systems (Mac and Linux):

url = "http://apdrc.soest.hawaii.edu:80/dods/public_data/ERA-40/"
filename = "daily-surface"
f = addfile(url + filename,"r")
print(f)

If this doesn't work, can you have your sysadmin tell you exactly which NCL binary he downloaded from the ESG website? The filename of the file he downloaded is all I need.

I tried the same test on a system where we have a firewall, and then I saw the same error that you got, both with the above test case, and with your URL. So, this leads me to believe you either have a non-opendap enabled version of NCL, or there's a bug somewhere.

Thanks,

--Mary

On Jul 24, 2012, at 7:44 AM, John Kerfoot wrote:

> The site was momentarily down when you tried to access it (I think).
> I just ran an ncdump on it and it is live again.
>
> As for the opendap, my sysadmin swears it was compiled with opendap,
> but I'm not so sure. I'm just trying to get all of my ducks in a row
> before I tell my sysadmin he's wrong. No need to bring trouble on
> myself if I don't need to:). I will say, however, that I've tried a
> few other urls on different TDS machines and keep getting the same
> error.
>
> thanks,
> John
>
>
> On Tue, Jul 24, 2012 at 9:40 AM, Mary Haley <haley@ucar.edu> wrote:
>> Hi John,
>>
>> There's definitely something strange going on here. I tried to open this file using an interactive NCL session and simply typing:
>>
>> ncl 0> a = addfile("http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc","r")
>>
>> It first gave me this message:
>>
>> syntax error, unexpected WORD_WORD, expecting SCAN_ATTR or SCAN_DATASET or SCAN_ERROR
>> context: <!DOCTYPE^ HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"><html><head><title>503 Service Temporarily Unavailable</title></head><body><h1>Service Temporarily Unavailable</h1><p>The server is temporarily unable to service yourrequest due to maintenance downtime or capacityproblems. Please try again later.</p><hr><address>Apache/2.2.16 (Amazon) Server at tds.maracoos.org Port 80</address></body></html>
>> fatal:NetCDF: Malformed or inaccessible DAP DDS
>> fatal:Could not open (http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc)
>>
>>
>> I then tried again, from a new ncl interactive session:
>>
>> ncl 0> a = addfile("http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc","r")
>> ncl 1> print(a)
>>
>> Variable: a
>> Type: file
>> filename: SST-Agg
>> path: http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc
>> file global attributes:
>> Conventions : CF-1.0
>> creator_name : Matthew Oliver and Danielle Haulsee
>> creator_email : moliver@udel.edu and dhaulsee@udel.edu
>> institution : University of Delaware Ocean Remote Sensing and Biogeography Group (ORB) and Rutgers University Coastal Ocean Observation Laboratory (RU-COOL)
>> url : http://www.ceoe.udel.edu, http://marine.rutgers.edu/cool/sat_data
>> source : satellite radiometer observation NOAA/POES AVHRR instrument
>> groundstation : RU-COOL L-band receiver at Rutgers University, New Jersey, USA
>> summary : MCSST calculation and image navigation by TeraScan software; Regridded to Mercator lon/lat projection. Processed and De-clouded at University of Delaware
>> history :
>> dimensions:
>> lat = 3661
>> lon = 4500
>> time = 20776
>> variables:
>> double lon ( lon )
>> long_name : Longitude
>> units : degrees_east
>>
>> double lat ( lat )
>> long_name : Latitude
>> units : degrees_north
>>
>> integer sat ( time )
>> units : NULL
>> _FillValue : -999
>> long_name : Satellite
>> missing_value : -999
>> . . .
>>
>> Can you please try this a couple of times in a row, and let me know if you still see problems.
>>
>> Also, I believe Dennis asked you offline if you had an OPeNDAP enabled version of NCL.
>>
>> --Mary
>>
>> On Jul 24, 2012, at 6:29 AM, John Kerfoot wrote:
>>
>>> I can't seem to read 64-bit offset NetCDF files using ncl 6.1.0-beta.
>>> Here's an example:
>>>
>>> arctic: bin > ~/production/bin/bash/nclRead.sh
>>> http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc
>>>
>>> Copyright (C) 1995-2012 - All Rights Reserved
>>> University Corporation for Atmospheric Research
>>> NCAR Command Language Version 6.1.0-beta
>>> The use of this software is governed by a License Agreement.
>>> See http://www.ncl.ucar.edu/ for more details.
>>> (0) Checking File: http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc
>>> fatal:NetCDF: Unknown file format
>>> fatal:Could not open (http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc)
>>>
>>> Variable: fid
>>> Type: file
>>> (0) File Missing Value : -1
>>>
>>> When I run ncdump on the url, I get the following:
>>>
>>> arctic: bin > ncdump -k http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc
>>> 64-bit offset
>>>
>>> But if I do the same thing using ncl 6.0, it works:
>>>
>>> arctic: bash > ~/production/bin/bash/nclRead.sh
>>> http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc
>>> command: /opt/ncl_ncarg-6.0.0.0/bin/ncl
>>> ncFile="http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc"
>>> Copyright (C) 1995-2011 - All Rights Reserved
>>> University Corporation for Atmospheric Research
>>> NCAR Command Language Version 6.0.0
>>> The use of this software is governed by a License Agreement.
>>> See http://www.ncl.ucar.edu/ for more details.
>>> (0) Checking File: http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc
>>>
>>> Variable: fid
>>> Type: file
>>> File path: http://tds.maracoos.org/thredds/dodsC/SST-Agg.nc
>>> Number of global attributes: 9
>>> Number of dimensions: 3
>>> Number of variables: 6
>>>
>>> Here's the info on my linux distro:
>>>
>>> arctic: bash > uname -a
>>> Linux arctic 2.6.32-279.1.1.el6.centos.plus.x86_64 #1 SMP Tue Jul 10
>>> 17:38:35 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
>>>
>>> Any help greatly appreciated.
>>>
>>> John
>>> _______________________________________________
>>> ncl-talk mailing list
>>> List instructions, subscriber options, unsubscribe:
>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>

_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Tue Jul 24 08:36:27 2012

This archive was generated by hypermail 2.1.8 : Tue Jul 24 2012 - 09:48:26 MDT