NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.

To learn about what's going on, see About the Archive Site.

Re: [netcdfgroup] Failure accessing an HYRAX OpenDAP server...

On Mon, Oct 17, 2016 at 11:15 AM, dmh@xxxxxxxx <dmh@xxxxxxxx> wrote:

> If you are using the netcdf-c library (thru python)
> then you may be able to get more info by prefixing the url
> So you might have
>     [log][show=fetch]http://...
>

nice hint! but I don't see anything useful. I've enclosed the log. Maybe
someone else can make some sense of it.






> =Dennis Heimbigner
>  Unidata
>
> On 10/17/2016 10:59 AM, Chris Barker wrote:
>
>>
>>
>> On Mon, Oct 17, 2016 at 6:38 AM, Kyle Wilcox <kyle@xxxxxxxxxxxxxxxxxxxx
>> <mailto:kyle@xxxxxxxxxxxxxxxxxxxx>> wrote:
>>
>>     I can confirm. Looks like a libdap/hyrax issue?
>>
>>
>> thanks -- does netcdf use libdap?
>>
>> but anyway, which one has the bug? One would need to see if the request
>> was being made correctly -- and I haqv no idea how to do that :-(
>>
>> -CHB
>>
>>
>>
>>
>>     DAS seems to work just fine while DODS is returning:
>>
>>     ...
>>     Error {
>>         code = -111;
>>         message = "libdap error transmitting DataDDS: Could not read the
>>     variable `ntimes'.";
>>     };
>>
>>     On Fri, Oct 14, 2016 at 5:43 PM Chris Barker <chris.barker@xxxxxxxx
>>     <mailto:chris.barker@xxxxxxxx>> wrote:
>>
>>         Hi all,
>>
>>         We're trying to use the netCDF4 python lib to access data on an
>>         what I thikn is a HYRAX server. It can create the Dataset object
>>         seemingly fine, and creates a variabel object fine -- but then
>>         gives me:
>>
>>         RuntimeError: NetCDF: file not found
>>
>>         when I try to extract some data from the variable.
>>
>>         Noett hat this seems to work fien with PyDAP -- so maybe that
>>         means that it's a netcdf lib problem, rather than a HYRAX problem.
>>
>>         But I have no idea how to debug this
>>
>>         I'm using a pretty recent version of the netcdf lib:
>>
>>         In [8]: netCDF4.getlibversion()
>>         Out[8]: u'4.4.1 of Aug 10 2016 18:32:53 $'
>>
>>         though the failure is the same with older versions as well. (and
>>         both on Windows and OS-X so far...)
>>
>>         I've enclosed a small python script that demonstrates the
>>         problem -- the problem url is in the script.
>>
>>         Thanks for any hints!
>>
>>         -CHB
>>
>>
>>
>>         --
>>
>>         Christopher Barker, Ph.D.
>>         Oceanographer
>>
>>         Emergency Response Division
>>         NOAA/NOS/OR&R            (206) 526-6959 <tel:(206)%20526-6959>
>>         voice
>>         7600 Sand Point Way NE   (206) 526-6329 <tel:(206)%20526-6329>
>>  fax
>>         Seattle, WA  98115       (206) 526-6317 <tel:(206)%20526-6317>
>>         main reception
>>
>>         Chris.Barker@xxxxxxxx <mailto:Chris.Barker@xxxxxxxx>
>>         _______________________________________________
>>         NOTE: All exchanges posted to Unidata maintained email lists are
>>         recorded in the Unidata inquiry tracking system and made publicly
>>         available through the web.  Users who post to any of the lists we
>>         maintain are reminded to remove any personal information that they
>>         do not want to be made public.
>>
>>
>>         netcdfgroup mailing list
>>         netcdfgroup@xxxxxxxxxxxxxxxx <mailto:netcdfgroup@xxxxxxxxxxxxxxxx
>> >
>>         For list information or to unsubscribe,  visit:
>>         http://www.unidata.ucar.edu/mailing_lists/
>>         <http://www.unidata.ucar.edu/mailing_lists/>
>>
>>
>>
>>
>> --
>>
>> Christopher Barker, Ph.D.
>> Oceanographer
>>
>> Emergency Response Division
>> NOAA/NOS/OR&R            (206) 526-6959   voice
>> 7600 Sand Point Way NE   (206) 526-6329   fax
>> Seattle, WA  98115       (206) 526-6317   main reception
>>
>> Chris.Barker@xxxxxxxx <mailto:Chris.Barker@xxxxxxxx>
>>
>>
>> _______________________________________________
>> NOTE: All exchanges posted to Unidata maintained email lists are
>> recorded in the Unidata inquiry tracking system and made publicly
>> available through the web.  Users who post to any of the lists we
>> maintain are reminded to remove any personal information that they
>> do not want to be made public.
>>
>>
>> netcdfgroup mailing list
>> netcdfgroup@xxxxxxxxxxxxxxxx
>> For list information or to unsubscribe,  visit:
>> http://www.unidata.ucar.edu/mailing_lists/
>>
>>


-- 

Christopher Barker, Ph.D.
Oceanographer

Emergency Response Division
NOAA/NOS/OR&R            (206) 526-6959   voice
7600 Sand Point Way NE   (206) 526-6329   fax
Seattle, WA  98115       (206) 526-6317   main reception

Chris.Barker@xxxxxxxx

Attachment: hyrax_fail.log
Description: Binary data

# Example of  failed requet from a HYRAX server

from netCDF4 import Dataset
nc = 
Dataset('[log][show=fetch]http://ingria.coas.oregonstate.edu:80/opendap/aggregation/ocean_time_aggregation.ncml')

print("Dataset loaded OK")

u = nc.variables['u']

print("Successfully Extracted a varaible object:")
print(u)

u_shape = u.shape  # this works ok
print("The variable object is seemingly valid:")
print("the shape is %s" % (u_shape,))

print("but I can't extract the actual data")

u_data = u[0, 0, 0:10, 0:10:]  # this does not work--"RuntimeError: NetCDF: 
file not found"
  • 2016 messages navigation, sorted by:
    1. Thread
    2. Subject
    3. Author
    4. Date
    5. ↑ Table Of Contents
  • Search the netcdfgroup archives: