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Adam, You probably think we have forgotten all about you :-) but this is where are at: http://www.unidata.ucar.edu/blogs/developer/en/entry/ipynb_cookbooks_to_create_cf Hopefully, some of that information can be useful to you. Next we have to work on the IDV to handle these data. Best, Unidata IDV Support > These are trajectories with different locations and different times. > > - Adam > > > -----Original Message----- > From: Unidata IDV Support [mailto:address@hidden] > Sent: Monday, June 16, 2014 6:02 PM > To: Adam Houston > Cc: address@hidden; Adam Houston > Subject: [IDV #IQR-639012]: Trajectories in NCDF format > > Adam, > > We have started looking into this again. > > Currently, the IDV has some capability to read and display CF compliant > trajectory files. I was reading our old emails on this topic, and I realized > that this comment stands in contradiction to earlier advice. For example, the > nemo.nc file which I point to below can be read by the IDV if you select a > Data Source Type of "Trajectory Sounding Files". However, I believe we are > still stuck (although hopefully for not much longer) for multiple > trajectories. > > Can you tell me a bit more about what you mean by multiple trajectories. Are > these trajectories from different locations, or perhaps the same location, > but spread out over time? > > Theoretically, using the nemo.nc as a template and identifying your multiple > trajectories with different station identifiers should eventually work. > > Best, > > Unidata IDV Support > > > > Adam, > > > > Apologies for the long delay. I have been consumed with the 5.0 > > release and have not had time to properly address this issue. > > > > I aim to start looking into this again soon. Last I looked, single CF > > trajectories seemed achievable, but *multiple* trajectories may be > > more challenging. I'll continue to dig in to it. > > > > Best, > > > > Unidata IDV Support > > > > > Hi guys, > > > > > > Any luck modifying the IDV to read CF compliant trajectory files? > > > > > > Thanks, > > > Adam > > > > > > > > > -----Original Message----- > > > From: Unidata IDV Support [mailto:address@hidden] > > > Sent: Monday, May 05, 2014 5:06 PM > > > To: Adam Houston > > > Cc: address@hidden > > > Subject: [IDV #IQR-639012]: Trajectories in NCDF format > > > > > > Ohh and I forgot the attachment. > > > > > > > Adam, > > > > > > > > We have spent quite a while digging into this problem. We (both > > > > you and Unidata) are treating the track.nc as a good template for > > > > creating trajectory data that can be read into the IDV. After some > > > > discussion here, we realize that is probably not a good idea. That > > > > track.nc file is not CF compliant, but following some less well > > > > known "NCAR-RAF/nimbus" format. Both of us are having a hard or > > > > impossible time using the "NCAR-RAF/nimbus" as a template or an example. > > > > > > > > What you really need to do is provide a CF compliant trajectory file. > > > > But there is a problem. The IDV cannot read CF compliant > > > > trajectory files. So we are in a catch 22. We can't use track.nc > > > > as a template, and the IDV cannot read CF compliant netCDF trajectories. > > > > > > > > So... I am going to fix the IDV so that it can read CF compliant > > > > trajectory files, but it is going to take some time. I hope I can > > > > get this task done by next week. > > > > > > > > In the meantime, I attach a better CF compliant trajectory file > > > > that the IDV should be able to read when I am done with my work. > > > > Please see that file attached as a template or example. > > > > > > > > As an alternative solution to all of this you may wish to check > > > > out the CSV data capability in the IDV. If you have the ability to > > > > produce your data as CSV you may wish to consider that option. > > > > > > > > Thanks for your patience and let me know if you have any > > > > additional concerns. > > > > > > > > Best Wishes, > > > > > > > > Unidata IDV Support > > > > > > > > > I'm building these files in IDL. I implemented the new template and > > > > > IDV still can't read it. Header: > > > > > > > > > > netcdf \2007finalinfo_trunc { > > > > > dimensions: > > > > > obs = 31 ; > > > > > trajectory = 12 ; > > > > > variables: > > > > > int trajectory(trajectory) ; > > > > > trajectory:cf_role = "trajectory_id" ; int time(trajectory, obs) > > > > > ; time:standard_name = "time" ; time:long_name = "time" ; > > > > > time:units = "seconds since 1970-01-01 00:00:00" ; time:axis = > > > > > "T" ; time:FillValue = "0.0f" ; float lat(trajectory, obs) ; > > > > > lat:standard_name = "latitude" ; lat:long_name = "latitude" ; > > > > > lat:units = "degrees_north" ; lat:axis = "Y" ; lat:FillValue = > > > > > "0.0f" ; float lon(trajectory, obs) ; lon:standard_name = > > > > > "longitude" ; lon:long_name = "longitude" ; lon:units = > > > > > "degrees_east" ; lon:axis = "X" ; lon:FillValue = "0.0f" ; float > > > > > z(trajectory, obs) ; z:standard_name = "altitude" ; z:long_name > > > > > = "height above mean sea level" ; z:units = "m" ; z:axis = "Z" ; > > > > > z:positive = "up" ; z:FillValue = "0.0f" ; > > > > > > > > > > // global attributes: > > > > > :featureType = "trajectory" ; > > > > > :Conventions = "CF-1.6" ; > > > > > } > > > > > > > > > > I'll upload the new ncdf to the motherlode repository. > > > > > > > > > > - Adam > > > > > > > > > > ________________________________________ > > > > > From: Unidata IDV Support <address@hidden> > > > > > Sent: Monday, May 05, 2014 9:25 AM > > > > > To: Adam Houston > > > > > Cc: address@hidden > > > > > Subject: [IDV #IQR-639012]: Trajectories in NCDF format > > > > > > > > > > Adam, > > > > > > > > > > How is this trajectory file created? > > > > > > > > > > I have been looking at your trajectory file, and I am not sure > > > > > why it is not working. The underlying library in the IDV is > > > > > complaining > > > > > about: > > > > > > > > > > - not finding Latitude coordinate > > > > > - not finding Longitude coordinate > > > > > - lat/lon/time coord not found. > > > > > > > > > > But I am wondering if track.nc is the best template for a trajectory. > > > > > > > > > > Theoretically, this one should be better: > > > > > > > > > > https://geo-ide.noaa.gov/wiki/index.php?title=NODC_NetCDF_Trajec > > > > > tory > > > > > _Template > > > > > > > > > > Can you try adhering to their suggestions? > > > > > > > > > > I am going to investigate on my end to ensure this is a better > > > > > template. > > > > > > > > > > Best, > > > > > > > > > > Unidata IDV Support > > > > > > > > > > > > > > > > The files have been uploaded: a single trajectory ncdf file and a > > > > > > multiple trajectory ncdf file. > > > > > > > > > > > > - Adam > > > > > > > > > > > > > > > > > > -----Original Message----- > > > > > > From: Unidata IDV Support > > > > > > [mailto:address@hidden] > > > > > > Sent: Friday, May 02, 2014 10:49 AM > > > > > > To: Adam Houston > > > > > > Cc: address@hidden > > > > > > Subject: [IDV #IQR-639012]: Trajectories in NCDF format > > > > > > > > > > > > Adam, > > > > > > > > > > > > Can you upload your data here and let us know when it is uploaded? > > > > > > > > > > > > http://motherlode.ucar.edu/repository/alias/idvupload > > > > > > > > > > > > Best, > > > > > > > > > > > > Unidata IDV Support > > > > > > > > > > > > > Full Name: Adam Houston > > > > > > > Email Address: address@hidden > > > > > > > Organization: University of Nebraska - Lincoln Package Version: > > > > > > > 4.1 Operating System: CentOS > > > > > > > Hardware: > > > > > > > Description of problem: I'm unable to get IDV to recognize NCDF > > > > > > > trajectory files that I'm creating. I've verified that IDV > > > > > > > recognizes a "track.nc" file available in one of the workshop > > > > > > > packages but neither my own single trajectory file nor my own > > > > > > > multiple trajectory file (this is what I really need to > > > > > > > visualize) can be read. To the best of my knowledge I'm adhering > > > > > > > to the CF Version 1.6 conventions (I've tested them in an online > > > > > > > compliance checker). I've included both headers below. > > > > > > > > > > > > > > netcdf \2007finalinfo { > > > > > > > dimensions: > > > > > > > time = 6 ; > > > > > > > trajid_strlen = 1 ; > > > > > > > variables: > > > > > > > char trajectory(trajid_strlen) ; trajectory:cf_role = > > > > > > > "trajectory_id" ; int time(time) ; time:standard_name = > > > > > > > "time" ; time:long_name = "time" ; time:units = "seconds > > > > > > > since 1970-01-01 00:00:00" ; float lat(time) ; > > > > > > > lat:standard_name = "latitude" ; lat:long_name = "latitude" > > > > > > > ; lat:units = "degrees_north" ; float > > > > > > > lon(time) ; lon:standard_name = "longitude" ; lon:long_name > > > > > > > = "longitude" ; lon:units = "degrees_east" > > > > > > > ; float z(time) ; z:standard_name = "altitude" ; z:long_name > > > > > > > = "height above mean sea level" ; z:units = "m" ; > > > > > > > > > > > > > > // global attributes: > > > > > > > :featureType = "trajectory" ; :Conventions = "CF-1.6" ; } > > > > > > > > > > > > > > ==== Multiple trajectories ==== > > > > > > > > > > > > > > netcdf \2007finalinfo { > > > > > > > dimensions: > > > > > > > obs = 28067 ; > > > > > > > trajectory = 3252 ; > > > > > > > trajid_strlen = 4 ; > > > > > > > variables: > > > > > > > char trajectory(trajectory, trajid_strlen) ; > > > > > > > trajectory:cf_role = "trajectory_id" ; int > > > > > > > rowSize(trajectory) ; rowSize:long_name = "number of obs for this > > > > > > > trajectory" ; rowSize:sample_dimension = "obs" > > > > > > > ; int time(obs) ; time:standard_name = "time" ; > > > > > > > time:long_name = "time" ; time:units = "seconds since > > > > > > > 1970-01-01 00:00:00" ; float > > > > > > > lat(obs) ; lat:standard_name = "latitude" ; lat:long_name = > > > > > > > "latitude" > > > > > > > ; lat:units = "degrees_north" ; float lon(obs) ; > > > > > > > lon:standard_name = "longitude" ; lon:long_name = "longitude" ; > > > > > > > lon:units = "degrees_east" > > > > > > > ; float z(obs) ; z:standard_name = "altitude" ; z:long_name > > > > > > > = "height above mean sea level" ; z:units = "m" ; > > > > > > > > > > > > > > // global attributes: > > > > > > > :featureType = "trajectory" ; :Conventions = "CF-1.6" ; } > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Ticket Details > > > > > > =================== > > > > > > Ticket ID: IQR-639012 > > > > > > Department: Support IDV > > > > > > Priority: Normal > > > > > > Status: Open > > > > > > > > > > > > > > > > > > > > > > > > > > > Ticket Details > > > > > =================== > > > > > Ticket ID: IQR-639012 > > > > > Department: Support IDV > > > > > Priority: Normal > > > > > Status: Open > > > > > > > > > > > > > > > > > > > > > > > > > > > > Ticket Details > > > =================== > > > Ticket ID: IQR-639012 > > > Department: Support IDV > > > Priority: Normal > > > Status: Open > > > > > > > > Ticket Details > =================== > Ticket ID: IQR-639012 > Department: Support IDV > Priority: Normal > Status: Open > > Ticket Details =================== Ticket ID: IQR-639012 Department: Support IDV Priority: Normal Status: Open