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Rostislav, I've been thinking about your question, and I'm afraid I could not come up with a mechanism to add the variables you mention to a netcdf subset. Unfortunately, for reasons to do with CF imlementation requirements, this is not a feature we support (though we may implement this in a future release). Essentially, if you were serving up individual files, it would be no problem to wrap the files in a bit of NcML to add the dimension and variables. However, as an aggregation, the best solution I can offer is to add the information as a global attribute, like this: <dataset name="Rostislav"> <featureCollection name="Rostislavnc4data" featureType="FMRC" harvest="true" path="rostislav/fmrc"> <metadata inherited="true"> <serviceName>all</serviceName> <dataFormat>netCDF</dataFormat> </metadata> <collection spec="C:/Users/madry/work/RostislavKouznetsov/.*nc4" /> <netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2"> <dimension name="dayhours" value="24"/> <attribute name="dayhours" value="24"/> </netcdf> </featureCollection> </dataset> It may be worth noting that the information you would like to add is more akin to metadata than actual data. Regards, Lansing Madry Unidata Boulder, Colorado > Hello Lansing, > > Thank you for ther reply. > On the second point. > If you download a file from > http://silam.fmi.fi/thredds/fileServer/fires/files/reanal_v1_3_global_2000.nc4 > you will find there a dimension > dayhours = 24 ; > and two variables > float dayhours(dayhours) ; > float hourlyadj(dayhours) ; > > They do not appear in files that come from netcdfsubset > http://silam.fmi.fi/thredds/ncss/grid/fires/files/reanal_v1_3_global_2000.nc4?var=emis_PM_FRP&north=70&west=0&east=20&south=50&horizStride=1&time_start=2000-01-01T00%3A00%3A00Z&time_end=2000-12-31T00%3A00%3A00Z&timeStride=1&addLatLon=true&accept=netcdf > > Is it possible to make the dimension "dayhours" and correspondinf > variables to appear in netcdf subsets? > > Thank you once more. > > Best regards, > > Rostislav > > > > On Sat, Apr 20, 2013 at 01:09:30AM +0300, Unidata THREDDS Support wrote: > >Rostislav, > > > >I was able to reproduce the failure you saw when asking for NetCDF4 versus > >NetCDF files. I wasn't sure why that was happening, so I asked the > >developer who worked on the ncss service. He thought it was probably a bug > >of some sort, so I opened a ticket to address the issue. I don't know if it > >is an easy fix or not yet, but it is in the queue. Thank you for bringing > >this to our attention! > > > >https://bugtracking.unidata.ucar.edu/browse/TDS-408 > > > >On your second point, I'm not sure what you mean by the small, non-grid > >variable. When I do an ncdump on the file, I see: > > > > dimensions: > > lon = 3600; > > lat = 1800; > > time = UNLIMITED; // (1 currently > > variables: > > float lon(lon=3600); > > :long_name = "longitude"; > > :units = "degrees_east"; > > :standard_name = "longitude"; > > > > float lat(lat=1800); > > :units = "degrees_north"; > > :standard_name = "latitude"; > > :long_name = "latitude"; > > > > double time(time=1); > > :units = "seconds since 1970-01-01 00:00:00"; > > :calendar = "standard"; > > :_ChunkSize = 1; // int > > > > float emis_PM_FRP(time=1, lat=1800, lon=3600); > > :units = "kg/s"; > > :_ChunkSize = 1, 1800, 3600; // int > > > > // global attributes: > > :CDI = "Climate Data Interface version 1.4.1"; > > :Conventions = "CF-1.0"; > > :netcdf_generated = "2013-04-15 09:01 UTC"; > > :producer = "Finnish Meteorological Institute"; > > :data_produced = "2013-04-13"; > > :dataset = "IS4FIRES wildland-fire emission reanalysis"; > > :contact = "Mikhail Sofiev: address@hidden"; > > :PM2P5_10fraction = 0.25999999046325684; // double > > :PM2P5fraction = 0.7400000095367432; // double > > :quantity = "PM emission rate"; > > :CDO = "Climate Data Operators version 1.4.1 > > (http://www.mpimet.mpg.de/cdo)"; > > > >Which is the non-grid variable you mean? > > > >On the third point, I will have to see if there is a way to get the > >information you want served up in fewer steps, but I don't know if it is > >possible off-hand. > > > >Regards, > > Lansing > >> Hello Lansing, > >> > >> Thank you for the detailed reply. > >> I have set up the service according to your instructions. > >> http://silam.fmi.fi/thredds/firesEmission.html > >> Few more questions. > >> > >> 1. The subsetting of files does not work with nc4 output > >> when accessing by file: > >> http://silam.fmi.fi/thredds/ncss/grid/fires/files/reanal_v1_3_global_2000.nc4?var=emis_PM_FRP&time_start=2000-01-01T00%3A00%3A00Z&time_end=2000-01-02T00%3A00%3A00Z&accept=netcdf > >> works, but > >> http://silam.fmi.fi/thredds/ncss/grid/fires/files/reanal_v1_3_global_2000.nc4?var=emis_PM_FRP&time_start=2000-01-01T00%3A00%3A00Z&time_end=2000-01-02T00%3A00%3A00Z&accept=netcdf4 > >> (difference in the last argument) > >> causes "I/O Exception handled : NetCDF: Invalid argument > >> nc_def_var_chunking on variable time" > >> Is it a bug or a feature? > >> > >> 2. I have a small non-grid variable in my file. It disappears when > >> accessing the files via thredds (except for http). > >> Can i make thredds to include it into any netcdf produced > >> from the datasets? > >> > >> 3. The data are obtained from reanalisys, so they have a single > >> time dimension. To get to the metadata page for "Fire emission this year" > >> i have to click "Fire emission this year" and then "Best timeseries". > >> Is it possible to avoid the second step? > >> > >> > >> Thank you once more! > >> > >> Best regards, > >> Rostislav > >> > >> > >> On Wed, Apr 17, 2013 at 11:49:39PM +0300, Unidata THREDDS Support wrote: > >> >Hello Rostislav, > >> > > >> >I downloaded a few days worth of files from your TDS and experimented > >> >with setting up a local TDS to help with your questions. To answer your > >> >first question, what you are observing is a feature, but I think you are > >> >misinterpreting the data. With a datasetScan such as you have, the time > >> >reported is the last time the file was modified (i.e., touched on your > >> >server), not the time or date information contained in the file. To > >> >answer your second question, I believe what you really want to do is to > >> >set up a featureCollection, instead of a datasetScan. Here is a simple > >> >example that I used locally: > >> > > >> ><?xml version="1.0" encoding="UTF-8"?> > >> ><catalog name="THREDDS Server Default Catalog : You must change this to > >> >fit your server!" > >> > > >> > xmlns="http://www.unidata.ucar.edu/namespaces/thredds/InvCatalog/v1.0" > >> > xmlns:xlink="http://www.w3.org/1999/xlink"> > >> > > >> > <service name="all" base="" serviceType="compound"> > >> > <service name="odap" serviceType="OpenDAP" base="/thredds/dodsC/" /> > >> > <service name="http" serviceType="HTTPServer" > >> > base="/thredds/fileServer/" /> > >> > <!--service name="wcs" serviceType="WCS" base="/thredds/wcs/" /--> > >> > <service name="wms" serviceType="WMS" base="/thredds/wms/" /> > >> > <service name="ncss" serviceType="NetcdfSubset" > >> > base="/thredds/ncss/grid/" /> > >> > </service> > >> > > >> > <dataset name="Rostislav"> > >> > <featureCollection name="Rostislavnc4data" featureType="FMRC" > >> > harvest="true" path="rostislav/fmrc"> > >> > <metadata inherited="true"> > >> > <serviceName>all</serviceName> > >> > <dataFormat>netCDF</dataFormat> > >> > </metadata> > >> > <collection spec="C:/Users/madry/work/RostislavKouznetsov/.*nc4" /> > >> > </featureCollection> > >> > </dataset> > >> ></catalog> > >> > > >> >This sets your data up to be served as a single logical unit via the > >> >NetCDF Subset Service. After you have changed the names and paths to > >> >suit your system, you will also need to edit the threddsConfig.xml file > >> >to turn the NetcdfSubsetService on. You do this by uncommenting the > >> >relevant block of xml and setting <allow> to true: > >> > > >> > <!-- > >> > The Netcdf Subset Service is off by default. > >> > --> > >> > <NetcdfSubsetService> > >> > <allow>true</allow> > >> > <scour>10 min</scour> > >> > <maxAge>-1 min</maxAge> > >> > </NetcdfSubsetService> > >> > > >> >Let me know if you need any further assistance. > >> > > >> >Regards, > >> > Lansing Madry > >> > Unidata > >> > Boulder, Colorado > >> > > >> >> Hello, > >> >> > >> >> I have put a collection of daily files into thredds, one field per day. > >> >> http://silam.fmi.fi/thredds/catalog/fires3/catalog.html > >> >> > >> >> Unfortunately it reports wrong times for them. e.g. > >> >> > >> >> http://silam.fmi.fi/thredds/catalog/fires3/catalog.html?dataset=fires3/reanal_v1_3_global_20130410.nc4 > >> >> > >> >> shows "date 2013-04-15T09:01:19Z (modified)" instead of something like > >> >> 2013-04-10T00:00:00Z. > >> >> > >> >> The dataset is described as: > >> >> <datasetScan name="Fires3" path="fires3" > >> >> location="/data/thredds/Fires/" suffix=".nc4"> > >> >> <serviceName>all</serviceName> > >> >> </datasetScan> > >> >> > >> >> Is it a bug or a feature? > >> >> > >> >> Can I somehow configure thredds to report these files as a single > >> >> dataset? > >> >> > >> >> Thank you! > >> >> > >> >> Best regards, > >> >> Rostislav > >> >> > >> >> -- > >> >> Rostislav Kouznetsov > >> >> > >> >> ************************************** > >> >> Air quality > >> >> Finnish Meteorological Institute > >> >> PL-503 FI-00101 Helsinki Finland > >> >> Phone: +358 29 539 4630 > >> >> ************************************** > >> >> > >> >> > >> > > >> > > >> >Ticket Details > >> >=================== > >> >Ticket ID: QCX-921252 > >> >Department: Support THREDDS > >> >Priority: Normal > >> >Status: Open > >> > > >> > >> -- > >> Rostislav Kouznetsov > >> > >> ************************************** > >> Air quality > >> Finnish Meteorological Institute > >> PL-503 FI-00101 Helsinki Finland > >> Phone: +358 29 539 4630 > >> ************************************** > >> > >> > > > > > >Ticket Details > >=================== > >Ticket ID: QCX-921252 > >Department: Support THREDDS > >Priority: Normal > >Status: Open > > > > -- > Rostislav Kouznetsov > > ************************************** > Air quality > Finnish Meteorological Institute > PL-503 FI-00101 Helsinki Finland > Phone: +358 29 539 4630 > ************************************** > > Ticket Details =================== Ticket ID: QCX-921252 Department: Support THREDDS Priority: High Status: Open