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[netCDFJava #KMJ-954554]: What determines GridCoordSystem.XAxis and .YAxis?

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  • Subject: [netCDFJava #KMJ-954554]: What determines GridCoordSystem.XAxis and .YAxis?
  • Date: Fri, 12 Mar 2010 13:59:01 -0700
If you look at this file in ToolsUI CoordSys tab:

Default Conventions error: NO projection name found 
Parsing with Convention = Default
 Coordinate Variable added = y for dimension    y = 689;
 Coordinate Variable added = time for dimension    time = 1;
 Coordinate Variable added = x for dimension    x = 1073;
 CoordinateAxis = latitude added; referenced from var= wind_speed
 CoordinateAxis = longitude added; referenced from var= wind_speed
 Time Coordinate Axis added (unit) = time from unit hours since 
2010-03-12T15:00:00Z
 created implicit CoordSystem 'y x' for var= longitude
 assigned implicit CoordSystem 'y x' for var= latitude
 created implicit CoordSystem 'time latitude y longitude x' for var= wind_speed

1) "Parsing with Convention = Default" means you are not using a convention.
2) "No projection name found" means that the projection is not getting found, 
so the grid coord system falls back to using the lat/lon coordinates.

It looks like all you need is a global attribute :Conventions="CF-1.4"


> > Whoops - sorry - I meant 4.1.2  ... the latest code available from
> > http://www.unidata.ucar.edu/software/netcdf-java/
> >
> > Thanks
> > Tom
> >
> > > I forget why your using 4.2.
> > >
> > >
> > >> Hello John,
> > >>
> > >> When the attached file is read by the 4.2 version of the NetCDF Java
> > >> API, the GridCoordSystem.getXHorizAxis() and .getYHorizAxis() methods
> > >> return the "longitude" and "latitude" variables rather than the "x" and
> > >> "y" variables.
> > >>
> > >> What determines which variables are interpreted as XHoriz and YHoriz
> > >> axes? How can we alter the file's metadata (attributes, var definitions,
> > >> etc.) so that the "x" and "y" variables are interpreted as XHorizAxis
> > >> and YHorizAxis?
> > >>
> > >> Thanks,
> > >> Tom
> > >>
> > >>
> > >>
> > >
> > >
> > > Ticket Details
> > > ===================
> > > Ticket ID: KMJ-954554
> > > Department: Support netCDF Java
> > > Priority: Normal
> > > Status: Open
> > >
> >
> >
> 


Ticket Details
===================
Ticket ID: KMJ-954554
Department: Support netCDF Java
Priority: Normal
Status: Closed