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[IDV #LPW-471935]: Plotting .hdf files in IDV



Hi again,

The embedded NcML is a bit hard to read so attached, you will find 
that same NcML file.

Best,

Unidata IDV Support

> Hi Alexa,
> 
> It is a little tricky but you can fix these problems with a bit of
> NcML. To get us going, let's look at the following NcML which can be
> read into the IDV and will allow you to view the
> `channel_14_brightness_temperature' over time. This file should be
> located next to your `hdf' files. Please read the comments in the NcML
> for more information about what is going on here.
> 
> ,----
> | <?xml version="1.0" encoding="UTF-8"?>
> | <netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";>
> |   <!-- Create a time coordinate variable that will be used for the 
> aggregation. -->
> |   <variable name="time" type="int" shape="time" >
> |     <!-- Let's add some units. Alexa: please make sure these units are 
> correct. -->
> |     <attribute name="units" value="minutes since 2014-04-04 19:09"/>
> |     <!-- Specify this variable as a time coordinate -->
> |     <attribute name="_CoordinateAxisType" value="Time" />
> |     <!-- Increment each file listed below by 10 minutes. Alexa, please make 
> sure this -->
> |     <!-- assumption about the times is correct. -->
> |     <values start="0" increment="10" />
> |   </variable>
> |   <!--   Specify the coordinates of time lat lon for this one variable. 
> Please use -->
> |   <!-- this as an example for other variables you are interersted in. In 
> other -->
> |   <!-- words, you can copy and paste this variable NcML element for your 
> other -->
> |   <!-- variables. -->
> |   <variable name="channel_14_brightness_temperature" shape="lines elements" 
> type="short">
> |     <attribute name="coordinates" value="time pixel_latitude 
> pixel_longitude" />
> |   </variable>
> |   <!-- Now you are ready to do your aggregation, which is the easy part at 
> this point -->
> |   <aggregation dimName="time" type="joinNew">
> |     <variableAgg name="T"/>
> |     <netcdf location="geocatL1.MTSAT-1R.2014044.190900.hdf"/>
> |     <netcdf location="geocatL1.MTSAT-1R.2014044.191900.hdf"/>
> |   </aggregation>
> | </netcdf>
> `----
> 
> In summary, this NcML should aggregate over time the two of HDF files
> you provided. You will see only one variable that is aggregated over
> time; `channel_14_brightness_temperature'.  I'll leave it up to you to
> do the others though do not hesitate to ask for help.
> 
> Also, if interested, there are also fancier tricks we can do here such
> as NcML can be smart enough to extract the times from the file names.
> 
> Best,
> 
> Unidata IDV Support
> 
> > Ok sounds promising. Here is the link to another file, which should differ 
> > only in time â 
> > https://drive.google.com/file/d/0B1jVlP9ZfAZCRDVyczU3N2NMbFU/view?usp=sharing
> >    -Alexa
> >
> > > On Mar 30, 2016, at 4:49 PM, Unidata IDV Support <address@hidden> wrote:
> > >
> > > Alexa,
> > >
> > > Indeed we may be able to patch things up with a bit of ncml. I only found 
> > > one
> > > file at the drive.google location. Would it be possible to see more so 
> > > that we
> > > have something to aggregate?
> > >
> > > Best,
> > >
> > > Unidata IDV Support
> > >
> > >> Hello IDV Support,
> > >>
> > >> I am working on reading in a number of HDF files using âaggregate 
> > >> grids by timeâ or similar. I am able to read the files in individually 
> > >> without a problem, but it looks like the time variable is not 
> > >> recognized. The error message is "Grid data source failed making data 
> > >> setâ.Dimension time does not existâ. Any ideas for how to specify 
> > >> the time variable? Could this be achieved with an .ncml script?
> > >>
> > >> Example file is located here: 
> > >> https://drive.google.com/file/d/0B1jVlP9ZfAZCRFhkRVM2aVVRVGc/view?usp=sharing
> > >>
> > >> All the best
> > >>
> > >> Alexa
> > >>
> > >
> > >
> > > Ticket Details
> > > ===================
> > > Ticket ID: LPW-471935
> > > Department: Support IDV
> > > Priority: Normal
> > > Status: Closed
> > >
> >
> >
> 


Ticket Details
===================
Ticket ID: LPW-471935
Department: Support IDV
Priority: Normal
Status: Closed

Attachment: alexa.ncml
Description: Binary data


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