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[IDV #GMD-821596]: netCDF file: IDV only sees one time level, and valid_range misses the negative lower bound

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  • Subject: [IDV #GMD-821596]: netCDF file: IDV only sees one time level, and valid_range misses the negative lower bound
  • Date: Mon, 28 Jan 2013 09:45:04 -0700
> Hi Yuan.
> Oh yes that is clearly an error, the time variable's data is all zeros. 
> Thanks. I should have known.
> I didn't make these files, NASA did (and nco operators acting in between).
> I just want to do the least work to be able to look at them. I will fix the 
> time variable.
> 
> 
> On a related note, I have some other files (cloud model output) that I wish I 
> could visualize, with too little header information.
> Here is one example:
> http://weather.rsmas.miami.edu:8080/repository/entry/show/UM+RAMADDA+Data+Repository/Users/brian+mapes/SAM_cloudmodel_64x64.nc+?entryid=f0c75517-b9e6-4a42-8b90-4835cf38255f
> It is from a periodic cloud model, so there is no "lat" and lon". I could 
> make some up (just rename x and y to lon and lat?)
> 
This dataset has different issues, the most critical one is missing a 
projection. Without a projection, there is no way to locate the lat/lon value 
for the x/y. I don't think you can simply rename x/y to lat/lon in this case. 
If you have any idea what is the projection here, I can help you to create a 
ncml file.

> IDV says these don't even seem to be .nc grid files.
> What is it looking for?
> 
> 
> THE GENERAL POINT:
> Is there a list of the minimum requirements for a .nc file?
> Yes I know there are "conventions" with pages and pages of recommendations. I 
> found those sites. That's good for institutions planning lasting data 
> libraries.
> But how can I find what is the FASTEST way to get IDV to recognize netCDF 
> grid volumes?
> 
There is no general list, each type of dataset can have different requirement. 
My understand is that the fastest way is to have your dataset in lat/lon grid.


Yuan
> 
> 
> 
> 
> 
> On Jan 24, 2013, at 3:55 PM, Unidata IDV Support wrote:
> >>> 2. That allows me to open it with IDV and make a plot.
> >>> I get an error message (I'm Feeling Lucky fails), but I click OK and
> >>> the Data Source appears.
> >>> But I only see one time level. Why?
> >>> [cid:05411747-3AB7-4C78-836D-0A426943A324]
> >>>
> >>
> >> I will download and let you know what is wrong.
> >>
> >>
> >> Yuan
> >
> > Brian,
> >     the time variable in this dataset is defined as:
> >
> > int time(time=36);
> >     :long_name = "time";
> >     :units = "minutes since 2010-02-04 14:30:00";
> >     :time_increment = 60000; // int
> >     :begin_date = 20100204; // int
> >     :begin_time = 143000; // int
> >     :_CoordinateAxisType = "Time";
> >
> > data:
> >
> >  {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 
> > 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
> >
> >
> > I understand what you try to do, but I don't think these attributes is in 
> > CF convention.
> >
> >
> > Yuan
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: GMD-821596
> > Department: Support IDV
> > Priority: Normal
> > Status: Open
> >
> 
> Brian Mapes
> address@hidden or address@hidden
> 
> 
> 
> 


Ticket Details
===================
Ticket ID: GMD-821596
Department: Support IDV
Priority: Normal
Status: Open