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Hi all: Jim is right that coordinates do not have to be any particular type. Time coordinates must be a numeric type with udunit compatible units. We are working here to fix the IDV code that assumes doubles. John > Jim, > > Thanks for the example data set. This file was helpful in finding several > problems. For this next iteration, please try the IDV nightly build > (tomorrow, > 8/27/2014). (The example file takes a while to load, just FYI.) Let us know > if > you run into problems. > > http://www.unidata.ucar.edu/downloads/idv/nightly/index.jsp > > Best, > > Unidata IDV Support > > > Hi. > > > > There is no CF requirement that a time variable be a double. In fact, it > > could even validly be a short or byte. This is also true for any other > > variable. The guidance is from the NODC template, not from CF. > > > > We have many datasets that we produce and consume where the time is > > stored as a 4-byte integer. > > > > Grace and peace, > > > > Jim > > > > On 8/21/14, 5:16 PM, Unidata IDV Support wrote: > > > Jim, > > > > > > I have started digging into this topic. From what I can tell, the > > > time field should be a double, but in the file you sent us, it is a float. > > > > > > We are following the CF guidance on trajectory data found here: > > > https://geo-ide.noaa.gov/wiki/index.php?title=NODC_NetCDF_Trajectory_Template > > > > > > Again, the blog entry here may be of some help: > > > http://www.unidata.ucar.edu/blogs/developer/en/entry/ipynb_cookbooks_to_create_cf > > > > > > Would it be possible to correct this float versus double problem at the > > > source? > > > > > > Alternatively, NCML may be able to help us here. > > > > > > Your thoughts? > > > > > > Best, > > > > > > Unidata IDV Support > > > > > >> Jim, > > >> > > >> Thanks for the information. I'll start digging into this but > > >> (un)fortunately I > > >> am out for a couple weeks so it will be a little while before I get back > > >> to you. > > >> Thanks for your patience. > > >> > > >> Best, > > >> > > >> Unidata IDV Support > > >> > > >>> Hi. > > >>> > > >>> I was using the nightly release IDV 5.0u1 from August 5. I've uploaded > > >>> one version of the file I was trying to view, which is using the > > >>> 'continuous ragged array' form. The name of the file is > > >>> cfs_ew_850hpa_1993_AFR.nc. I have the same data stored using the > > >>> 'multidimensional array' form, but it was too big to upload (the upload > > >>> folder quota was exceeded). > > >>> > > >>> I hope this is helpful. I'm actually trying to validate the file by > > >>> verifying that some neutral 3rd party application properly handles it, > > >>> so there are no guarantees that what I have is correct! > > >>> > > >>> Grace and peace, > > >>> > > >>> Jim > > >>> > > >>> On 8/6/14, 6:22 PM, Unidata IDV Support wrote: > > >>>> Jim, > > >>>> > > >>>> First off, what version of the IDV are you looking at? Only the > > >>>> nightly release > > >>>> or IDV 5.0u1 (which has not been released yet, but very soon) has this > > >>>> new > > >>>> trajectory feature. Secondly, can you upload the file in question to > > >>>> http://motherlode.ucar.edu/repository/alias/idvupload and let us know > > >>>> when it is > > >>>> there? I am eager to see some real trajectory data since everything I > > >>>> have > > >>>> experimented with thus far has been canned. Moreover, there are other > > >>>> researchers wanting this feature so real data will be useful for me. > > >>>> > > >>>> Thanks for you help. > > >>>> > > >>>> Best, > > >>>> > > >>>> Unidata IDV Support > > >>>> > > >>>>> Hi. > > >>>>> > > >>>>> That is good timing! I tried opening my file and received this error: > > >>>>> > > >>>>> Problem opening file:/Users/jbiard/Desktop/For > > >>>>> Hilawe/cfs_ew_850hpa_1993_AFR.nc > > >>>>> java.lang.IllegalArgumentException: Type is float, > > >>>>> must be double > > >>>>> Type is float, must be double > > >>>>> > > >>>>> This is interesting, since there is no constraint on variable type in > > >>>>> CF. > > >>>>> > > >>>>> Grace and peace, > > >>>>> > > >>>>> Jim > > >>>>> > > >>>>> On 8/6/14, 2:53 PM, Unidata IDV Support wrote: > > >>>>>> Jim, > > >>>>>> > > >>>>>> Good timing. > > >>>>>> > > >>>>>> As of IDV 5u1 which will be release this week, the IDV can now > > >>>>>> handle multiple > > >>>>>> trajectories in one CF-compliant file. When wanting to view these > > >>>>>> data, select a > > >>>>>> Data Source Type of "Trajectory Sounding Files". You will have to > > >>>>>> build the > > >>>>>> trajectory file in a CF compliant manner as described here: > > >>>>>> http://www.unidata.ucar.edu/blogs/developer/en/entry/ipynb_cookbooks_to_create_cf. > > >>>>>> > > >>>>>> This new IDV functionality should still be considered beta quality > > >>>>>> and there > > >>>>>> could very well still be problems. Please keep us up-to-date on your > > >>>>>> progress. > > >>>>>> > > >>>>>> Best, > > >>>>>> > > >>>>>> Unidata IDV Support > > >>>>>> > > >>>>>> > > >>>>>>> Jim > > >>>>>>> > > >>>>>>> We plot trajectories here. > > >>>>>>> > > >>>>>>> http://www.esrl.noaa.gov/psd/cgi-bin/data/trajtool/traj.pl > > >>>>>>> > > >>>>>>> We use Fortran code to calculate the trajectories, stored the > > >>>>>>> output in > > >>>>>>> nertCDF and then use a NCL script to plot them. The script works > > >>>>>>> pretty > > >>>>>>> well (except where trajectories pass over 0E). We looked into CF > > >>>>>>> complaint > > >>>>>>> netCDF trajectories standard a while back but didn't implement > > >>>>>>> them. Part > > >>>>>>> of the reason was that the code output into it's own netCDF format. > > >>>>>>> Still, > > >>>>>>> we could have reread and stored the data. I think we would have > > >>>>>>> needed to > > >>>>>>> change how time was handled. Also, times went backward for back > > >>>>>>> trajectories and we weren't clear if that was okay. > > >>>>>>> > > >>>>>>> We may try to transition to CF at some point. > > >>>>>>> > > >>>>>>> Cathy Smith > > >>>>>>> > > >>>>>>> > > >>>>>>> On 8/6/14 8:42 AM, Jim Biard wrote: > > >>>>>>> > > >>>>>>> Hi. > > >>>>>>> > > >>>>>>> We are working on building a CF-compliant trajectory dataset. I'd > > >>>>>>> like to > > >>>>>>> be able to verify correctness by using an existing application to > > >>>>>>> plot the > > >>>>>>> trajectories, but I can't seem to find any applications that are > > >>>>>>> "trajectory aware". Any suggestions? > > >>>>>>> > > >>>>>>> Grace and peace, > > >>>>>>> > > >>>>>>> Jim > > >>>>>>> -- > > >>>>>>> CF-metadata mailing > > >>>>>>> address@hidden.eduhttp://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > > >>>>>>> > > >>>>>>> -- > > >>>>>>> ---------------------------------------------- > > >>>>>>> > > >>>>>>> Emails about data/webpages may get quicker responses from emailing > > >>>>>>> address@hidden > > >>>>>>> > > >>>>>>> _______________________________________________ > > >>>>>>> CF-metadata mailing list > > >>>>>>> address@hidden > > >>>>>>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > > >>>>>>> > > >>>>>> Ticket Details > > >>>>>> =================== > > >>>>>> Ticket ID: GAI-830760 > > >>>>>> Department: Support IDV > > >>>>>> Priority: Normal > > >>>>>> Status: Closed > > >>>> Ticket Details > > >>>> =================== > > >>>> Ticket ID: GAI-830760 > > >>>> Department: Support IDV > > >>>> Priority: Normal > > >>>> Status: Closed > > > > > > Ticket Details > > > =================== > > > Ticket ID: GAI-830760 > > > Department: Support IDV > > > Priority: Normal > > > Status: Closed > > > > > > > -- > > CICS-NC <http://www.cicsnc.org/> Visit us on > > Facebook <http://www.facebook.com/cicsnc> *Jim Biard* > > *Research Scholar* > > Cooperative Institute for Climate and Satellites NC <http://cicsnc.org/> > > North Carolina State University <http://ncsu.edu/> > > NOAA's National Climatic Data Center <http://ncdc.noaa.gov/> > > 151 Patton Ave, Asheville, NC 28801 > > e: address@hidden > > o: +1 828 271 4900 > > > > > > > > > > > > > Ticket Details =================== Ticket ID: GAI-830760 Department: Support IDV Priority: Normal Status: Closed