Hi Rich, Walt:
you wouldnt have to write an IOSP, just a CoordSysBuilder.John, I'm down here at NOAA's National Data Buoy Center (NDBC) and could really use some advice from you about how to handle their NetCDF4 data in groups. They really like the groups, and they are working internationally with the OceanSites and Ifremer folks, who also like this group structure.
1) Could they keep their data in groups, but then write an IOSP so that it would appear to TDS as a group of datasets, which each could be CDM compliant? Or would you recommend splitting them up and writing valid CDM netcdf files, and keeping the information about the group some other way.
2) Is it even a good idea to store using groups? It seems there could be advantages to storing at a more atomic level, to enable more database or metadata searching capabilities.
So it really depends on who you want to use the data, and what they need.
Do you have time to talk today at all? Pick a time.
sorry i missed your window I guess
On Thu, Feb 10, 2011 at 1:29 PM, John Caron<address@hidden> wrote:Hi Rich, Walt:
These actually have groups, not structures.
Im not against using netcdf-4 data model, but its new territory for CF. Currently, these files are not readable by the CDM poinmt featire layer (of course,CDM canread the underlying data just fine, it just doesnt understand what should be done with it).
At minimum, if you are going your own way with conventions, we want you to document them and give them a name and put that name in the "Conventions" global attribute.
On 2/9/2011 7:45 PM, Rich Signell wrote:Walt,
I'm not sure this style of NetCDF4 (with structures) is a good choice for archiving NDBC buoy data. Although there is nothing wrong with using NetCDF4, there are not very many applications that can deal with NetCDF4 structures. Unidata and the CF community recommend storing time series data using the "Point" featureType, described here:
If you put the attached file you sent on the latest THREDDS
The OpenDAP access form appears:
but when you try to load the OPeNDAP URL in ToolsUI, you get: "Variable name (wind speed) must be unique within group"
We can talk more about this when I visit NDBC next week (or more tomorrow, if you wish).
I could take a stab at creating a valid Point featureType NetCDF 4 file from this data if it would be helpful.
---------- Forwarded message ---------- From: Walt McCall<address@hidden> Date: Wed, Feb 9, 2011 at 5:05 PM Subject: NDBC NetCDF-4 Files To: Rich Signell<address@hidden>
Attached is our NetCDF-4 file that we are about to start using for archiving all buoy data. Would you mind taking a look at it and seeing if there is anything that seems non-standard? Also, do you know if the new THREDDS 4.2 server will handle NetCDF-4? We tried THREDDS 4.1, but found that it didn't handle our files well; so we are installing 4.2 and plan on giving that a try tomorrow.
If there is a problem with THREDDS, maybe we can work on it Tuesday in addition to the enhancements.
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