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Adam, Good to know. Please keep us posted. We will be releasing a new version of the IDV shortly that will have these improvements (you can use the nightly as well). It is entirely possible that problems could still crop up but I am fairly confident we can get through any issues now that I have a better understanding of this topic. Closing this ticket for now. Best, Unidata IDV Support > Good timing. Our field work in August will collect data that I could use to > test out this functionality (I have data now that I could use but I doubt > that I'll have much of a chance to test it out before we collect these new > data). I'll make sure to let you guys know how it goes. Thanks!! > > - Adam > > > -----Original Message----- > From: Unidata IDV Support [mailto:address@hidden] > Sent: Wednesday, July 30, 2014 5:10 PM > To: Adam Houston > Cc: address@hidden; Adam Houston > Subject: [IDV #IQR-639012]: Trajectories in NCDF format > > Adam, > > We have a new version of IDV we would like you to try tomorrow. > > http://www.unidata.ucar.edu/downloads/idv/nightly/index.jsp > > This version of the IDV should handle multiple trajectories. > > Again, please select a Data Source Type of "Trajectory Sounding Files". > > You will have to build the trajectory file in a CF compliant manner as > described in the blog entry below. > > Please keep us up-to-date on your progress. > > Best Wishes, > > Unidata IDV Support > > > 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_t > > o_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_Tr > > > > > > > ajec > > > > > > > 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 > > Ticket Details =================== Ticket ID: IQR-639012 Department: Support IDV Priority: Normal Status: Closed